nilfs2: eliminate staggered calls to kunmap in nilfs_rename

In nilfs_rename(), calls to nilfs_put_page() to release pages obtained
with nilfs_find_entry() or nilfs_dotdot() are alternated in the normal
path.

When replacing the kernel memory mapping method from kmap to
kmap_local_{page,folio}, this violates the constraint on the calling order
of kunmap_local().

Swap the order of nilfs_put_page calls where the kmap sections of multiple
pages overlap so that they are nested, allowing direct replacement of
nilfs_put_page() -> unmap_and_put_page().

Without this reordering, that replacement will cause a kernel WARNING in
kunmap_local_indexed() on architectures with high memory mapping.

Link: https://lkml.kernel.org/r/20231127143036.2425-3-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

nilfs2: move page release outside of nilfs_delete_entry and nilfs_set_link

Patch series "nilfs2: Folio conversions for directory paths".

This series applies page->folio conversions to nilfs2 directory
operations.  This reduces hidden compound_head() calls and also converts
deprecated kmap calls to kmap_local in the directory code.

Although nilfs2 does not yet support large folios, Matthew has done his
best here to include support for large folios, which will be needed for
devices with large block sizes.

This series corresponds to the second half of the original post [1], but
with two complementary patches inserted at the beginning and some
adjustments, to prevent a kmap_local constraint violation found during
testing with highmem mapping.

[1] https://lkml.kernel.org/r/20231106173903.1734114-1-willy@infradead.org

I have reviewed all changes and tested this for regular and small block
sizes, both on machines with and without highmem mapping.  No issues
found.

This patch (of 17):

In a few directory operations, the call to nilfs_put_page() for a page
obtained using nilfs_find_entry() or nilfs_dotdot() is hidden in
nilfs_set_link() and nilfs_delete_entry(), making it difficult to track
page release and preventing change of its call position.

By moving nilfs_put_page() out of these functions, this makes the page
get/put correspondence clearer and makes it easier to swap
nilfs_put_page() calls (and kunmap calls within them) when modifying
multiple directory entries simultaneously in nilfs_rename().

Also, update comments for nilfs_set_link() and nilfs_delete_entry() to
reflect changes in their behavior.

To make nilfs_put_page() visible from namei.c, this moves its definition
to nilfs.h and replaces existing equivalents to use it, but the exposure
of that definition is temporary and will be removed on a later kmap ->
kmap_local conversion.

Link: https://lkml.kernel.org/r/20231127143036.2425-1-konishi.ryusuke@gmail.com
Link: https://lkml.kernel.org/r/20231127143036.2425-2-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

softlockup: serialized softlockup's log

If multiple CPUs trigger softlockup at the same time with
'softlockup_all_cpu_backtrace=0', the softlockup's logs will appear
staggeredly in dmesg, which will affect the viewing of the logs for
developer.  Since the code path for outputting softlockup logs is not a
kernel hotspot and the performance requirements for the code are not
strict, locks are used to serialize the softlockup log output to improve
the readability of the logs.

Link: https://lkml.kernel.org/r/20231123084022.10302-1-lizhe.67@bytedance.com
Signed-off-by: Li Zhe <lizhe.67@bytedance.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Cc: Lecopzer Chen <lecopzer.chen@mediatek.com>
Cc: Pingfan Liu <kernelfans@gmail.com>
Cc: Zefan Li <lizefan.x@bytedance.com>
Cc: John Ogness <john.ogness@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

kexec_file: load kernel at top of system RAM if required

Patch series "kexec_file: Load kernel at top of system RAM if required".

Justification:
==============

Kexec_load interface has been doing top down searching and loading
kernel/initrd/purgtory etc to prepare for kexec reboot.  In that way, the
benefits are that it avoids to consume and fragment limited low memory
which satisfy DMA buffer allocation and big chunk of continuous memory
during system init; and avoids to stir with BIOS/FW reserved or occupied
areas, or corner case handling/work around/quirk occupied areas when doing
system init.  By the way, the top-down searching and loading of kexec-ed
kernel is done in user space utility code.

For kexec_file loading, even if kexec_buf.top_down is 'true', it's simply
ignored.  It calls walk_system_ram_res() directly to go through all
resources of System RAM bottom up, to find an available memory region,
then call locate_mem_hole_callback() to allocate memory in that found
memory region from top to down.  This is not expected and inconsistent
with kexec_load.

Implementation
===============

In patch 1, introduce a new function walk_system_ram_res_rev() which is a
variant of walk_system_ram_res(), it walks through a list of all the
resources of System RAM in reversed order, i.e., from higher to lower.

In patch 2, check if kexec_buf.top_down is 'true' in
kexec_walk_resources(), if yes, call walk_system_ram_res_rev() to find
memory region of system RAM from top to down to load kernel/initrd etc.

Background information: ======================= And I ever tried this in
the past in a different way, please see below link.  In the post, I tried
to adjust struct sibling linking code, replace the the singly linked list
with list_head so that walk_system_ram_res_rev() can be implemented in a
much easier way.  Finally I failed.
https://lore.kernel.org/all/20180718024944.577-4-bhe@redhat.com/

This time, I picked up the patch from AKASHI Takahiro's old post and made
some change to take as the current patch 1:
https://lists.infradead.org/pipermail/linux-arm-kernel/2017-September/531456.html

This patch (of 2):

Kexec_load interface has been doing top down searching and loading
kernel/initrd/purgtory etc to prepare for kexec reboot.  In that way, the
benefits are that it avoids to consume and fragment limited low memory
which satisfy DMA buffer allocation and big chunk of continuous memory
during system init; and avoids to stir with BIOS/FW reserved or occupied
areas, or corner case handling/work around/quirk occupied areas when doing
system init.  By the way, the top-down searching and loading of kexec-ed
kernel is done in user space utility code.

For kexec_file loading, even if kexec_buf.top_down is 'true', it's simply
ignored.  It calls walk_system_ram_res() directly to go through all
resources of System RAM bottom up, to find an available memory region,
then call locate_mem_hole_callback() to allocate memory in that found
memory region from top to down.  This is not expected and inconsistent
with kexec_load.

Here check if kexec_buf.top_down is 'true' in kexec_walk_resources(), if
yes, call the newly added walk_system_ram_res_rev() to find memory region
of system RAM from top to down to load kernel/initrd etc.

Link: https://lkml.kernel.org/r/20231114091658.228030-1-bhe@redhat.com
Link: https://lkml.kernel.org/r/20231114091658.228030-3-bhe@redhat.com
Signed-off-by: Baoquan He <bhe@redhat.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

resource: add walk_system_ram_res_rev()

This function, being a variant of walk_system_ram_res() introduced in
commit 8c86e70acead ("resource: provide new functions to walk through
resources"), walks through a list of all the resources of System RAM in
reversed order, i.e., from higher to lower.

It will be used in kexec_file code to load kernel, initrd etc when
preparing kexec reboot.

Link: https://lkml.kernel.org/r/ZVTA6z/06cLnWKUz@MiWiFi-R3L-srv
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Signed-off-by: Baoquan He <bhe@redhat.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

powerpc: pmd_move_must_withdraw() is only needed for CONFIG_TRANSPARENT_HUGEPAGE

This is required for the later patch "Makefile.extrawarn: turn on
missing-prototypes globally".

Link: https://lkml.kernel.org/r/20231127132809.45c2b398@canb.auug.org.au
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

usb: fsl-mph-dr-of: mark fsl_usb2_mpc5121_init() static

This function is only called locally and should always have been static:

drivers/usb/host/fsl-mph-dr-of.c:291:5: error: no previous prototype for 'fsl_usb2_mpc5121_init' [-Werror=missing-prototypes]

Link: https://lkml.kernel.org/r/20231123110506.707903-6-arnd@kernel.org
Fixes: 230f7ede6c2f ("USB: add USB EHCI support for MPC5121 SoC")
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Kees Cook <keescook@chromium.org>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nicolas Schier <nicolas@fjasle.eu>
Cc: Palmer Dabbelt <palmer@rivosinc.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Richard Henderson <richard.henderson@linaro.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Tudor Ambarus <tudor.ambarus@linaro.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

x86: sta2x11: include header for sta2x11_get_instance() prototype

sta2x11_get_instance() is a global function declared in asm/sta2x11.h, but
this header is not included before the definition, causing a warning:

arch/x86/pci/sta2x11-fixup.c:95:26: error: no previous prototype for 'sta2x11_get_instance' [-Werror=missing-prototypes]

Add the missing #include.

Link: https://lkml.kernel.org/r/20231123110506.707903-5-arnd@kernel.org
Fixes: 83125a3a189e ("x86, platform: Initial support for sta2x11 I/O hub")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Kees Cook <keescook@chromium.org>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nicolas Schier <nicolas@fjasle.eu>
Cc: Palmer Dabbelt <palmer@rivosinc.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Richard Henderson <richard.henderson@linaro.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Tudor Ambarus <tudor.ambarus@linaro.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

sched: fair: move unused stub functions to header

These four functions have a normal definition for CONFIG_FAIR_GROUP_SCHED,
and empty one that is only referenced when FAIR_GROUP_SCHED is disabled
but CGROUP_SCHED is still enabled.  If both are turned off, the functions
are still defined but the misisng prototype causes a W=1 warning:

kernel/sched/fair.c:12544:6: error: no previous prototype for 'free_fair_sched_group'
kernel/sched/fair.c:12546:5: error: no previous prototype for 'alloc_fair_sched_group'
kernel/sched/fair.c:12553:6: error: no previous prototype for 'online_fair_sched_group'
kernel/sched/fair.c:12555:6: error: no previous prototype for 'unregister_fair_sched_group'

Move the alternatives into the header as static inline functions with the
correct combination of #ifdef checks to avoid the warning without adding
even more complexity.

[A different patch with the same description got applied by accident
 and was later reverted, but the original patch is still missing]

Link: https://lkml.kernel.org/r/20231123110506.707903-4-arnd@kernel.org
Fixes: 7aa55f2a5902 ("sched/fair: Move unused stub functions to header")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Kees Cook <keescook@chromium.org>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nicolas Schier <nicolas@fjasle.eu>
Cc: Palmer Dabbelt <palmer@rivosinc.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Richard Henderson <richard.henderson@linaro.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Tudor Ambarus <tudor.ambarus@linaro.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

jffs2: mark __jffs2_dbg_superblock_counts() static

This function is only called locally and does not need to be global.
Since there is no external prototype, gcc warns about the non-static
definition:

fs/jffs2/debug.c:160:6: error: no previous prototype for '__jffs2_dbg_superblock_counts' [-Werror=missing-prototypes]

Link: https://lkml.kernel.org/r/20231123110506.707903-3-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Reviewed-by: Zhihao Cheng <chengzhihao1@huawei.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Kees Cook <keescook@chromium.org>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nicolas Schier <nicolas@fjasle.eu>
Cc: Palmer Dabbelt <palmer@rivosinc.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Richard Henderson <richard.henderson@linaro.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

ida: make 'ida_dump' static

Patch series "Treewide: enable -Wmissing-prototypes", v3.

At this point, there are five architectures with a number of known
regressions: alpha, nios2, mips, sh and sparc.  In the previous version of
this patch, I had turned off the missing prototype warnings for the 15
architectures that still had issues, but since there are only five left, I
think we can leave the rest to the maintainers (Cc'd here) as well.

The series is also likely to cause occasional build regressions on
linux-next as developers add new code that misses prototypes.  Hopefully
this should be resolved by the time the patches make it into a release and
everyone gets the warnings right away.

This patch (of 6):

There is no global declaration for ida_dump() and no other callers, so
make it static to avoid this warning:

lib/test_ida.c:16:6: error: no previous prototype for 'ida_dump'

Link: https://lkml.kernel.org/r/20231123110506.707903-1-arnd@kernel.org
Link: https://lkml.kernel.org/r/20231123110506.707903-2-arnd@kernel.org
Fixes: 8ab8ba38d488 ("ida: Start new test_ida module")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nicolas Schier <nicolas@fjasle.eu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Richard Henderson <richard.henderson@linaro.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Tudor Ambarus <tudor.ambarus@linaro.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Kees Cook <keescook@chromium.org>
Cc: Palmer Dabbelt <palmer@rivosinc.com>
Cc: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mips: kexec: include linux/reboot.h

Two functions are provided for kexec, but the mips implementation is
missing the corresponding #include statment:

arch/mips/kernel/machine_kexec.c:136:1: error: no previous prototype for 'machine_shutdown' [-Werror=missing-prototypes]
arch/mips/kernel/machine_kexec.c:152:1: error: no previous prototype for 'machine_crash_shutdown' [-Werror=missing-prototypes]

Link: https://lkml.kernel.org/r/20231204115710.2247097-21-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Stephen Rothwell <sfr@rothwell.id.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mips: smp: fix setup_profiling_timer() prototype

The function is unconditionally defined in smp.c but is conditionally
declared in a header that is not included here.

arch/mips/kernel/smp.c:473:5: error: no previous prototype for 'setup_profiling_timer' [-Werror=missing-prototypes]

Add the missing #include and #ifdef to match the declaration.

Link: https://lkml.kernel.org/r/20231204115710.2247097-20-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Stephen Rothwell <sfr@rothwell.id.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mips: hide conditionally unused functions

A couple of functions are defined unconditionally but have a conditional
declaration:

arch/mips/mm/tlb-r4k.c:461:12: error: no previous prototype for 'add_temporary_entry' [-Werror=missing-prototypes]
arch/mips/mm/pgtable-64.c:92:7: error: no previous prototype for 'mk_pmd' [-Werror=missing-prototypes]
arch/mips/mm/pgtable-64.c:101:6: error: no previous prototype for 'set_pmd_at' [-Werror=missing-prototypes]

Since there are no callers in these configurations, add the same #ifdef
checks around the definitions.

Link: https://lkml.kernel.org/r/20231204115710.2247097-19-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Stephen Rothwell <sfr@rothwell.id.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mips: suspend: include linux/suspend.h as needed

A couple of functions are defined by the architecture and declared in
linux/suspend.h, but mips is lacking the corresponding #include statement
before the definition:

arch/mips/power/cpu.c:16:6: warning: no previous prototype for 'save_processor_state' [-Wmissing-prototypes]
arch/mips/power/cpu.c:26:6: warning: no previous prototype for 'restore_processor_state' [-Wmissing-prototypes]
arch/mips/power/cpu.c:36:5: warning: no previous prototype for 'pfn_is_nosave' [-Wmissing-prototypes]
arch/mips/power/hibernate.c:6:5: warning: no previous prototype for 'swsusp_arch_resume' [-Wmissing-prototypes]

Link: https://lkml.kernel.org/r/20231204115710.2247097-18-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Stephen Rothwell <sfr@rothwell.id.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mips: mt: include asm/mips_mt.h

These two functions have a global prototype but the header is not included
before the function definitions:

arch/mips/kernel/mips-mt.c:50:6: error: no previous prototype for 'mips_mt_regdump' [-Werror=missing-prototypes]
arch/mips/kernel/mips-mt.c:159:6: error: no previous prototype for 'mips_mt_set_cpuoptions' [-Werror=missing-prototypes]

Link: https://lkml.kernel.org/r/20231204115710.2247097-16-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Stephen Rothwell <sfr@rothwell.id.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mips: spram: fix missing prototype warning for spram_config

arch/mips/kernel/spram.c:194:6: error: no previous prototype for 'spram_config' [-Werror=missing-prototypes]

Link: https://lkml.kernel.org/r/20231204115710.2247097-15-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Stephen Rothwell <sfr@rothwell.id.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mips: add missing declarations

These are three more functions that are only called from assembler and
only need a declaration to avoid the -Wmissing-prototypes warnings:

arch/mips/kernel/signal.c:904:17: error: no previous prototype for 'do_notify_resume' [-Werror=missing-prototypes]
arch/mips/kernel/traps.c:370:6: error: no previous prototype for 'show_registers' [-Werror=missing-prototypes]
arch/mips/kernel/smp.c:352:17: error: no previous prototype for 'start_secondary' [-Werror=missing-prototypes]

Link: https://lkml.kernel.org/r/20231204115710.2247097-14-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Stephen Rothwell <sfr@rothwell.id.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mips: move cache declarations into header

Some of the cache functions are declared only for their callers, e.g.

arch/mips/mm/c-r3k.c:28:15: error: no previous prototype for 'r3k_cache_size' [-Werror=missing-prototypes]
arch/mips/mm/c-r3k.c:63:15: error: no previous prototype for 'r3k_cache_lsize' [-Werror=missing-prototypes]
arch/mips/mm/c-r4k.c:1703:6: error: no previous prototype for 'r4k_cache_init' [-Werror=missing-prototypes]
arch/mips/mm/sc-mips.c:255:5: error: no previous prototype for 'mips_sc_init' [-Werror=missing-prototypes]

Move all the declarations to asm/cache.h and asm/r4kcache.h where they
can be seen by the function definitions.

Link: https://lkml.kernel.org/r/20231204115710.2247097-13-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Stephen Rothwell <sfr@rothwell.id.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mips: fix tlb_init() prototype

There are two definitions for tlb_init(), but no global declaration:

arch/mips/mm/tlb-r4k.c:552:6: error: no previous prototype for 'tlb_init' [-Werror=missing-prototypes]
arch/mips/mm/tlb-r3k.c:244:6: error: no previous prototype for 'tlb_init' [-Werror=missing-prototypes]

Move the declaration to asm/setup.h and included it as needed.

Link: https://lkml.kernel.org/r/20231204115710.2247097-12-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Stephen Rothwell <sfr@rothwell.id.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mips: fix setup_zero_pages() prototype

setup_zero_pages() has a local declaration in a platform specific header,
but that is not seen in the file it is defined in:

arch/mips/mm/init.c:60:6: error: no previous prototype for 'setup_zero_pages' [-Werror=missing-prototypes]

Move it to the corresponding global header and include that where needed.

Link: https://lkml.kernel.org/r/20231204115710.2247097-11-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Stephen Rothwell <sfr@rothwell.id.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mips: unhide uasm_in_compat_space_p() declaration

uasm_in_compat_space_p() has a conditional declaration but is defined
unconditionally because of another local user, which causes a warning:

arch/mips/mm/uasm.c:421:5: error: no previous prototype for 'uasm_in_compat_space_p' [-Werror=missing-prototypes]

Make the declaration unconditional to avoid this.

Link: https://lkml.kernel.org/r/20231204115710.2247097-10-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Stephen Rothwell <sfr@rothwell.id.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mips: move jump_label_apply_nops() declaration to header

Instead of an extern declaration in the C file with the caller, move it to
an appropriate header, avoiding

arch/mips/kernel/jump_label.c:93:6: error: no previous prototype for 'jump_label_apply_nops' [-Werror=missing-prototypes]

Link: https://lkml.kernel.org/r/20231204115710.2247097-9-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Stephen Rothwell <sfr@rothwell.id.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mips: move build_tlb_refill_handler() prototype

Instead of having a declaration for each caller, have one that is shared
with the function definition, which avoids a warning:

arch/mips/mm/tlbex.c:2547:6: error: no previous prototype for 'build_tlb_refill_handler' [-Werror=missing-prototypes]

Link: https://lkml.kernel.org/r/20231204115710.2247097-8-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Stephen Rothwell <sfr@rothwell.id.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mips: mark local function static if possible

These two functions are global but have no extern prototypes or other
callers, so it's best to mark them as static, avoiding these warnings:

arch/mips/kernel/mips-cm.c:204:13: error: no previous prototype for '__mips_cm_l2sync_phys_base' [-Werror=missing-prototypes]
arch/mips/mm/c-r4k.c:1827:12: error: no previous prototype for 'r4k_cache_init_pm' [-Werror=missing-prototypes]

Link: https://lkml.kernel.org/r/20231204115710.2247097-7-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Stephen Rothwell <sfr@rothwell.id.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mips: signal: move sigcontext declarations to header

Function declarations should be in a shared header to ensure the
prototypes match the definition:

arch/mips/kernel/signal.c:439:5: error: no previous prototype for 'setup_sigcontext' [-Werror=missing-prototypes]
arch/mips/kernel/signal.c:516:5: error: no previous prototype for 'restore_sigcontext' [-Werror=missing-prototypes]

Link: https://lkml.kernel.org/r/20231204115710.2247097-6-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Stephen Rothwell <sfr@rothwell.id.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mips: rs870e: stop exporting local functions

These four functions are exported, but don't have any users, and no
prototypes, which now causes warnings:

drivers/platform/mips/rs780e-acpi.c:35:6: error: no previous prototype for 'pm_iowrite' [-Werror=missing-prototypes]
drivers/platform/mips/rs780e-acpi.c:41:4: error: no previous prototype for 'pm_ioread' [-Werror=missing-prototypes]
drivers/platform/mips/rs780e-acpi.c:47:6: error: no previous prototype for 'pm2_iowrite' [-Werror=missing-prototypes]
drivers/platform/mips/rs780e-acpi.c:53:4: error: no previous prototype for 'pm2_ioread' [-Werror=missing-prototypes]

Link: https://lkml.kernel.org/r/20231204115710.2247097-5-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Stephen Rothwell <sfr@rothwell.id.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mips: add missing declarations for trap handlers

These exception handlers are all called from assembly code, so they don't
normally need a declaration, but without one we now get warnings:

arch/mips/mm/fault.c:323:17: error: no previous prototype for 'do_page_fault' [-Werror=missing-prototypes]
arch/mips/kernel/traps.c:447:17: error: no previous prototype for 'do_be' [-Werror=missing-prototypes]
arch/mips/kernel/traps.c:752:17: error: no previous prototype for 'do_ov' [-Werror=missing-prototypes]
arch/mips/kernel/traps.c:874:17: error: no previous prototype for 'do_fpe' [-Werror=missing-prototypes]
arch/mips/kernel/traps.c:1027:17: error: no previous prototype for 'do_bp' [-Werror=missing-prototypes]
arch/mips/kernel/traps.c:1114:17: error: no previous prototype for 'do_tr' [-Werror=missing-prototypes]
arch/mips/kernel/traps.c:1151:17: error: no previous prototype for 'do_ri' [-Werror=missing-prototypes]
arch/mips/kernel/traps.c:1402:17: error: no previous prototype for 'do_cpu' [-Werror=missing-prototypes]
arch/mips/kernel/traps.c:1507:17: error: no previous prototype for 'do_msa_fpe' [-Werror=missing-prototypes]
arch/mips/kernel/traps.c:1527:17: error: no previous prototype for 'do_msa' [-Werror=missing-prototypes]
arch/mips/kernel/traps.c:1548:17: error: no previous prototype for 'do_mdmx' [-Werror=missing-prototypes]
arch/mips/kernel/traps.c:1560:17: error: no previous prototype for 'do_watch' [-Werror=missing-prototypes]
arch/mips/kernel/traps.c:1587:17: error: no previous prototype for 'do_mcheck' [-Werror=missing-prototypes]
arch/mips/kernel/traps.c:1612:17: error: no previous prototype for 'do_mt' [-Werror=missing-prototypes]
arch/mips/kernel/traps.c:1648:17: error: no previous prototype for 'do_dsp' [-Werror=missing-prototypes]
arch/mips/kernel/traps.c:1656:17: error: no previous prototype for 'do_reserved' [-Werror=missing-prototypes]
arch/mips/kernel/traps.c:1832:17: error: no previous prototype for 'cache_parity_error' [-Werror=missing-prototypes]
arch/mips/kernel/traps.c:1880:17: error: no previous prototype for 'do_ftlb' [-Werror=missing-prototypes]
arch/mips/kernel/traps.c:1909:17: error: no previous prototype for 'do_gsexc' [-Werror=missing-prototypes]
arch/mips/kernel/traps.c:1944:6: error: no previous prototype for 'ejtag_exception_handler' [-Werror=missing-prototypes]
arch/mips/kernel/traps.c:1989:17: error: no previous prototype for 'nmi_exception_handler' [-Werror=missing-prototypes]
arch/mips/kernel/unaligned.c:1516:17: error: no previous prototype for 'do_ade' [-Werror=missing-prototypes]

Link: https://lkml.kernel.org/r/20231204115710.2247097-4-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Stephen Rothwell <sfr@rothwell.id.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mips: add asm/syscalls.h header

System call prototypes are generally in linux/syscalls.h, but there are a
couple of mips specific entry points that are missing there:

arch/mips/kernel/signal.c:636:17: error: no previous prototype for 'sys_sigreturn' [-Werror=missing-prototypes]
arch/mips/kernel/signal.c:673:17: error: no previous prototype for 'sys_rt_sigreturn' [-Werror=missing-prototypes]
arch/mips/kernel/syscall.c:51:16: error: no previous prototype for 'sysm_pipe' [-Werror=missing-prototypes]
arch/mips/kernel/mips-mt-fpaff.c:65:17: error: no previous prototype for 'mipsmt_sys_sched_setaffinity' [-Werror=missing-prototypes]
arch/mips/kernel/mips-mt-fpaff.c:157:17: error: no previous prototype for 'mipsmt_sys_sched_getaffinity' [-Werror=missing-prototypes]

Add these to a new asm/syscalls.h as we have in other architectures.

Link: https://lkml.kernel.org/r/20231204115710.2247097-3-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Stephen Rothwell <sfr@rothwell.id.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mips: decompress: fix add missing prototypes

Patch series "mips: address -Wmissing-prototypes warnings".

Address the -Wmissing-prototypes warnings that showed up in mips as the
last major architecture after my patch to enable the option everywhere.

This patch (of 20):

The mips decompressor has some string functions defined locally that are
not declared in the right place:

arch/mips/boot/compressed/dbg.c:12:13: error: no previous prototype for 'putc' [-Werror=missing-prototypes]
arch/mips/boot/compressed/dbg.c:16:6: error: no previous prototype for 'puts' [-Werror=missing-prototypes]
arch/mips/boot/compressed/dbg.c:26:6: error: no previous prototype for 'puthex' [-Werror=missing-prototypes]
arch/mips/boot/compressed/string.c:11:7: error: no previous prototype for 'memcpy' [-Werror=missing-prototypes]
arch/mips/boot/compressed/string.c:22:7: error: no previous prototype for 'memset' [-Werror=missing-prototypes]
arch/mips/boot/compressed/string.c:32:15: error: no previous prototype for 'memmove' [-Werror=missing-prototypes]
arch/mips/boot/compressed/decompress.c:43:6: error: no previous prototype for 'error' [-Werror=missing-prototypes]
arch/mips/boot/compressed/decompress.c:91:6: error: no previous prototype for 'decompress_kernel' [-Werror=missing-prototypes]

Include the string.h header where needed and add a decompress.h header to
have shared prototypes for the rest.

Link: https://lkml.kernel.org/r/20231204115710.2247097-1-arnd@kernel.org
Link: https://lkml.kernel.org/r/20231204115710.2247097-2-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Stephen Rothwell <sfr@rothwell.id.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

s390/traps: only define is_valid_bugaddr() under CONFIG_GENERIC_BUG

When building with -Wmissing-prototypes without CONFIG_GENERIC_BUG, there
is a warning about a missing prototype for is_valid_bugaddr():

  arch/s390/kernel/traps.c:46:5: warning: no previous prototype for 'is_valid_bugaddr' [-Wmissing-prototypes]
     46 | int is_valid_bugaddr(unsigned long addr)
        |     ^~~~~~~~~~~~~~~~

The prototype is only declared with CONFIG_GENERIC_BUG, so only define the
function under the same condition to clear up the warning, which matches
other architectures.

Link: https://lkml.kernel.org/r/20231130-s390-missing-prototypes-v1-2-799d3cf07fb7@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Jan Höppner <hoeppner@linux.ibm.com>
Cc: Stefan Haberland <sth@linux.ibm.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

s390/dasd: remove dasd_stats_generic_show()

Patch series "s390: A couple of fixes for -Wmissing-prototypes".

This series resolves a couple of -Wmissing-prototypes that I see in my
builds of -next, even though the issues appear to be latent.  This
addresses issues which will be exposed by the later patch
"Makefile.extrawarn: turn on missing-prototypes globally".

This patch (of 2):

With CONFIG_DASD_PROFILE=n, there is a warning that
dasd_stats_generic_show() is missing a prototype:

  drivers/s390/block/dasd.c:1109:5: warning: no previous prototype for 'dasd_stats_generic_show' [-Wmissing-prototypes]
   1109 | int dasd_stats_generic_show(struct seq_file *m, void *v)
        |     ^~~~~~~~~~~~~~~~~~~~~~~

This function has been unused since its introduction in commit
4fa52aa7a82f ("[S390] dasd: add enhanced DASD statistics interface"),
remove it to clear up the warning.

Link: https://lkml.kernel.org/r/20231130-s390-missing-prototypes-v1-0-799d3cf07fb7@kernel.org
Link: https://lkml.kernel.org/r/20231130-s390-missing-prototypes-v1-1-799d3cf07fb7@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Jan Höppner <hoeppner@linux.ibm.com>
Cc: Stefan Haberland <sth@linux.ibm.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

hexagon: traps: add internal prototypes for functions only called from asm

Clang warns:

  arch/hexagon/kernel/traps.c:284:6: warning: no previous prototype for function 'do_genex' [-Wmissing-prototypes]
    284 | void do_genex(struct pt_regs *regs)
        |      ^
  arch/hexagon/kernel/traps.c:284:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
    284 | void do_genex(struct pt_regs *regs)
        | ^
        | static
  arch/hexagon/kernel/traps.c:341:6: warning: no previous prototype for function 'do_trap0' [-Wmissing-prototypes]
    341 | void do_trap0(struct pt_regs *regs)
        |      ^
  arch/hexagon/kernel/traps.c:341:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
    341 | void do_trap0(struct pt_regs *regs)
        | ^
        | static
  arch/hexagon/kernel/traps.c:418:6: warning: no previous prototype for function 'do_machcheck' [-Wmissing-prototypes]
    418 | void do_machcheck(struct pt_regs *regs)
        |      ^
  arch/hexagon/kernel/traps.c:418:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
    418 | void do_machcheck(struct pt_regs *regs)
        | ^
        | static
  arch/hexagon/kernel/traps.c:428:6: warning: no previous prototype for function 'do_debug_exception' [-Wmissing-prototypes]
    428 | void do_debug_exception(struct pt_regs *regs)
        |      ^
  arch/hexagon/kernel/traps.c:428:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
    428 | void do_debug_exception(struct pt_regs *regs)
        | ^
        | static

These functions are only called from assembly or this translation unit,
so just add prototypes right above the definitions to silence the
warnings.

Link: https://lkml.kernel.org/r/20231130-hexagon-missing-prototypes-v1-19-5c34714afe9e@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brian Cain <bcain@quicinc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

hexagon: traps: remove sys_syscall()

Clang warns:

  arch/hexagon/kernel/traps.c:335:6: warning: no previous prototype for function 'sys_syscall' [-Wmissing-prototypes]
    335 | long sys_syscall(void)
        |      ^
  arch/hexagon/kernel/traps.c:335:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
    335 | long sys_syscall(void)
        | ^
        | static

This function is not used anywhere, so remove it.

Link: https://lkml.kernel.org/r/20231130-hexagon-missing-prototypes-v1-18-5c34714afe9e@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brian Cain <bcain@quicinc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

hexagon: irq: add prototype for arch_do_IRQ()

Clang warns:

  arch/hexagon/kernel/vm_events.c:83:6: warning: no previous prototype for function 'arch_do_IRQ' [-Wmissing-prototypes]
     83 | void arch_do_IRQ(struct pt_regs *regs)
        |      ^
  arch/hexagon/kernel/vm_events.c:83:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
     83 | void arch_do_IRQ(struct pt_regs *regs)
        | ^
        | static

This function is only called from assembly but the irq header is a
reasonable place to put a prototype to silence the warning.

Link: https://lkml.kernel.org/r/20231130-hexagon-missing-prototypes-v1-17-5c34714afe9e@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brian Cain <bcain@quicinc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

hexagon: vm_events: remove unused dummy_handler()

Clang warns:

  arch/hexagon/kernel/vm_events.c:76:6: warning: no previous prototype for function 'dummy_handler' [-Wmissing-prototypes]
     76 | void dummy_handler(struct pt_regs *regs)
        |      ^
  arch/hexagon/kernel/vm_events.c:76:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
     76 | void dummy_handler(struct pt_regs *regs)
        | ^
        | static

This function appears to be entirely unused, so remove it.

Link: https://lkml.kernel.org/r/20231130-hexagon-missing-prototypes-v1-16-5c34714afe9e@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brian Cain <bcain@quicinc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

hexagon: vdso: include asm/elf.h for arch_setup_additional_pages() prototype

Clang warns:

  arch/hexagon/kernel/vdso.c:49:5: warning: no previous prototype for function 'arch_setup_additional_pages' [-Wmissing-prototypes]
     49 | int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
        |     ^
  arch/hexagon/kernel/vdso.c:49:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
     49 | int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
        | ^
        | static
  1 warning generated.

Include the header that declares the prototype to clear up the warning.

Link: https://lkml.kernel.org/r/20231130-hexagon-missing-prototypes-v1-15-5c34714afe9e@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brian Cain <bcain@quicinc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

hexagon: process: add internal prototype for do_work_pending()

Clang warns:

  arch/hexagon/kernel/process.c:155:5: warning: no previous prototype for function 'do_work_pending' [-Wmissing-prototypes]
    155 | int do_work_pending(struct pt_regs *regs, u32 thread_info_flags)
        |     ^
  arch/hexagon/kernel/process.c:155:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
    155 | int do_work_pending(struct pt_regs *regs, u32 thread_info_flags)
        | ^
        | static

This function is only referenced from assembly, so it does not technically
need a prototype.  Add one right above the definition anyways to clear up
the warning.

Link: https://lkml.kernel.org/r/20231130-hexagon-missing-prototypes-v1-14-5c34714afe9e@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brian Cain <bcain@quicinc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

hexagon: process: include linux/cpu.h for arch_cpu_idle() prototype

Clang warns:

  arch/hexagon/kernel/process.c:43:6: warning: no previous prototype for function 'arch_cpu_idle' [-Wmissing-prototypes]
     43 | void arch_cpu_idle(void)
        |      ^
  arch/hexagon/kernel/process.c:43:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
     43 | void arch_cpu_idle(void)
        | ^
        | static

This prototype is declared in include/linux/cpu.h, include it in
process.c to clear up the warning.

Link: https://lkml.kernel.org/r/20231130-hexagon-missing-prototypes-v1-13-5c34714afe9e@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brian Cain <bcain@quicinc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

hexagon: reset: include linux/reboot.h for prototypes

Clang warns about missing prototypes that are declared in this header:

  arch/hexagon/kernel/reset.c:9:6: warning: no previous prototype for function 'machine_power_off' [-Wmissing-prototypes]
      9 | void machine_power_off(void)
        |      ^
  arch/hexagon/kernel/reset.c:9:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
      9 | void machine_power_off(void)
        | ^
        | static
  arch/hexagon/kernel/reset.c:15:6: warning: no previous prototype for function 'machine_halt' [-Wmissing-prototypes]
     15 | void machine_halt(void)
        |      ^
  arch/hexagon/kernel/reset.c:15:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
     15 | void machine_halt(void)
        | ^
        | static
  arch/hexagon/kernel/reset.c:19:6: warning: no previous prototype for function 'machine_restart' [-Wmissing-prototypes]
     19 | void machine_restart(char *cmd)
        |      ^
  arch/hexagon/kernel/reset.c:19:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
     19 | void machine_restart(char *cmd)
        | ^
        | static
  3 warnings generated.

Link: https://lkml.kernel.org/r/20231130-hexagon-missing-prototypes-v1-12-5c34714afe9e@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brian Cain <bcain@quicinc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

hexagon: signal: switch to SYSCALL_DEFINE0 for sys_rt_sigreturn()

Clang warns:

  arch/hexagon/kernel/signal.c:223:16: warning: no previous prototype for function 'sys_rt_sigreturn' [-Wmissing-prototypes]
    223 | asmlinkage int sys_rt_sigreturn(void)
        |                ^
  arch/hexagon/kernel/signal.c:223:12: note: declare 'static' if the function is not intended to be used outside of this translation unit
    223 | asmlinkage int sys_rt_sigreturn(void)
        |            ^
        |            static
  1 warning generated.

Switch to the SYSCALL_DEFINE0() macro, which automatically declares a
prototype.

Link: https://lkml.kernel.org/r/20231130-hexagon-missing-prototypes-v1-11-5c34714afe9e@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brian Cain <bcain@quicinc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

hexagon: time: include asm/delay.h for prototypes

Clang warns about missing prototypes that are declared in this header:

  arch/hexagon/kernel/time.c:209:6: warning: no previous prototype for function '__delay' [-Wmissing-prototypes]
    209 | void __delay(unsigned long cycles)
        |      ^
  arch/hexagon/kernel/time.c:209:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
    209 | void __delay(unsigned long cycles)
        | ^
        | static
  arch/hexagon/kernel/time.c:224:6: warning: no previous prototype for function '__udelay' [-Wmissing-prototypes]
    224 | void __udelay(unsigned long usecs)
        |      ^
  arch/hexagon/kernel/time.c:224:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
    224 | void __udelay(unsigned long usecs)
        | ^
        | static

Link: https://lkml.kernel.org/r/20231130-hexagon-missing-prototypes-v1-10-5c34714afe9e@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brian Cain <bcain@quicinc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

hexagon: time: mark time_init_deferred() as static

Clang warns:

  arch/hexagon/kernel/time.c:163:13: warning: no previous prototype for function 'time_init_deferred' [-Wmissing-prototypes]
    163 | void __init time_init_deferred(void)
        |             ^
  arch/hexagon/kernel/time.c:163:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
    163 | void __init time_init_deferred(void)
        | ^
        | static

This function is not used outside of this translation unit so mark it as
static to resolve the warning.

Link: https://lkml.kernel.org/r/20231130-hexagon-missing-prototypes-v1-9-5c34714afe9e@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brian Cain <bcain@quicinc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

hexagon: time: include asm/time.h for prototypes

Clang warns about missing prototypes that are declared in this header:

  arch/hexagon/kernel/time.c:118:6: warning: no previous prototype for function 'setup_percpu_clockdev' [-Wmissing-prototypes]
    118 | void setup_percpu_clockdev(void)
        |      ^
  arch/hexagon/kernel/time.c:118:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
    118 | void setup_percpu_clockdev(void)
        | ^
        | static
  arch/hexagon/kernel/time.c:135:6: warning: no previous prototype for function 'ipi_timer' [-Wmissing-prototypes]
    135 | void ipi_timer(void)
        |      ^
  arch/hexagon/kernel/time.c:135:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
    135 | void ipi_timer(void)
        | ^
        | static

Link: https://lkml.kernel.org/r/20231130-hexagon-missing-prototypes-v1-8-5c34714afe9e@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brian Cain <bcain@quicinc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

hexagon: vm_tlb: include asm/tlbflush.h for prototypes

Clang warns about several missing prototypes that are declared in this
header:

  arch/hexagon/mm/vm_tlb.c:25:6: warning: no previous prototype for function 'flush_tlb_range' [-Wmissing-prototypes]
     25 | void flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
        |      ^
  arch/hexagon/mm/vm_tlb.c:25:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
     25 | void flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
        | ^
        | static
  arch/hexagon/mm/vm_tlb.c:37:6: warning: no previous prototype for function 'flush_tlb_one' [-Wmissing-prototypes]
     37 | void flush_tlb_one(unsigned long vaddr)
        |      ^
  arch/hexagon/mm/vm_tlb.c:37:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
     37 | void flush_tlb_one(unsigned long vaddr)
        | ^
        | static
  arch/hexagon/mm/vm_tlb.c:47:6: warning: no previous prototype for function 'tlb_flush_all' [-Wmissing-prototypes]
     47 | void tlb_flush_all(void)
        |      ^
  arch/hexagon/mm/vm_tlb.c:47:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
     47 | void tlb_flush_all(void)
        | ^
        | static
  arch/hexagon/mm/vm_tlb.c:56:6: warning: no previous prototype for function 'flush_tlb_mm' [-Wmissing-prototypes]
     56 | void flush_tlb_mm(struct mm_struct *mm)
        |      ^
  arch/hexagon/mm/vm_tlb.c:56:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
     56 | void flush_tlb_mm(struct mm_struct *mm)
        | ^
        | static
  arch/hexagon/mm/vm_tlb.c:66:6: warning: no previous prototype for function 'flush_tlb_page' [-Wmissing-prototypes]
     66 | void flush_tlb_page(struct vm_area_struct *vma, unsigned long vaddr)
        |      ^
  arch/hexagon/mm/vm_tlb.c:66:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
     66 | void flush_tlb_page(struct vm_area_struct *vma, unsigned long vaddr)
        | ^
        | static
  arch/hexagon/mm/vm_tlb.c:78:6: warning: no previous prototype for function 'flush_tlb_kernel_range' [-Wmissing-prototypes]
     78 | void flush_tlb_kernel_range(unsigned long start, unsigned long end)
        |      ^
  arch/hexagon/mm/vm_tlb.c:78:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
     78 | void flush_tlb_kernel_range(unsigned long start, unsigned long end)
        | ^
        | static
  6 warnings generated.

Link: https://lkml.kernel.org/r/20231130-hexagon-missing-prototypes-v1-7-5c34714afe9e@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brian Cain <bcain@quicinc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

hexagon: vm_fault: include asm/vm_fault.h for prototypes

Clang warns:

  arch/hexagon/mm/vm_fault.c:157:6: warning: no previous prototype for function 'read_protection_fault' [-Wmissing-prototypes]
    157 | void read_protection_fault(struct pt_regs *regs)
        |      ^
  arch/hexagon/mm/vm_fault.c:157:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
    157 | void read_protection_fault(struct pt_regs *regs)
        | ^
        | static
  arch/hexagon/mm/vm_fault.c:164:6: warning: no previous prototype for function 'write_protection_fault' [-Wmissing-prototypes]
    164 | void write_protection_fault(struct pt_regs *regs)
        |      ^
  arch/hexagon/mm/vm_fault.c:164:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
    164 | void write_protection_fault(struct pt_regs *regs)
        | ^
        | static
  arch/hexagon/mm/vm_fault.c:171:6: warning: no previous prototype for function 'execute_protection_fault' [-Wmissing-prototypes]
    171 | void execute_protection_fault(struct pt_regs *regs)
        |      ^
  arch/hexagon/mm/vm_fault.c:171:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
    171 | void execute_protection_fault(struct pt_regs *regs)
        | ^
        | static

The prototypes for these functions are defined in asm/vm_fault.h, so
include it to pick them up and silence the warnings.

Link: https://lkml.kernel.org/r/20231130-hexagon-missing-prototypes-v1-6-5c34714afe9e@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brian Cain <bcain@quicinc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

hexagon: vm_fault: mark do_page_fault() as static

Clang warns:

  arch/hexagon/mm/vm_fault.c:36:6: warning: no previous prototype for function 'do_page_fault' [-Wmissing-prototypes]
     36 | void do_page_fault(unsigned long address, long cause, struct pt_regs *regs)
        |      ^
  arch/hexagon/mm/vm_fault.c:36:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
     36 | void do_page_fault(unsigned long address, long cause, struct pt_regs *regs)
        | ^
        | static

This function is not used outside of this translation unit, so mark it
as static.

Link: https://lkml.kernel.org/r/20231130-hexagon-missing-prototypes-v1-5-5c34714afe9e@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brian Cain <bcain@quicinc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

hexagon: smp: mark handle_ipi() and start_secondary() as static

Clang warns:

  arch/hexagon/kernel/smp.c:82:13: warning: no previous prototype for function 'handle_ipi' [-Wmissing-prototypes]
     82 | irqreturn_t handle_ipi(int irq, void *desc)
        |             ^
  arch/hexagon/kernel/smp.c:82:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
     82 | irqreturn_t handle_ipi(int irq, void *desc)
        | ^
        | static
  arch/hexagon/kernel/smp.c:127:6: warning: no previous prototype for function 'start_secondary' [-Wmissing-prototypes]
    127 | void start_secondary(void)
        |      ^
  arch/hexagon/kernel/smp.c:127:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
    127 | void start_secondary(void)
        | ^
        | static
  2 warnings generated.

These functions are not used outside of this translation unit, so mark
them as static.

Link: https://lkml.kernel.org/r/20231130-hexagon-missing-prototypes-v1-4-5c34714afe9e@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brian Cain <bcain@quicinc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

hexagon: mm: include asm/setup.h for setup_arch_memory()'s prototype

Clang warns:

  arch/hexagon/mm/init.c:138:13: warning: no previous prototype for function 'setup_arch_memory' [-Wmissing-prototypes]
    138 | void __init setup_arch_memory(void)
        |             ^
  arch/hexagon/mm/init.c:138:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
    138 | void __init setup_arch_memory(void)
        | ^
        | static

The prototype is in asm/setup.h, include it to clear up the warning.

Link: https://lkml.kernel.org/r/20231130-hexagon-missing-prototypes-v1-3-5c34714afe9e@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brian Cain <bcain@quicinc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

hexagon: mm: mark paging_init() as static

Clang warns:

  arch/hexagon/mm/init.c:89:13: warning: no previous prototype for function 'paging_init' [-Wmissing-prototypes]
     89 | void __init paging_init(void)
        |             ^
  arch/hexagon/mm/init.c:89:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
     89 | void __init paging_init(void)
        | ^
        | static

This function is only used within this translation unit, so mark it static
as suggested.

Link: https://lkml.kernel.org/r/20231130-hexagon-missing-prototypes-v1-2-5c34714afe9e@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brian Cain <bcain@quicinc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

hexagon: uaccess: remove clear_user_hexagon()

Patch series "hexagon: Fix up instances of -Wmissing-prototypes".

This series fixes all the instances of -Wmissing-prototypes in
arch/hexagon, as it is about to be enabled globally in a default build.

This patch (of 19):

Clang warns:

  arch/hexagon/mm/uaccess.c:39:15: warning: no previous prototype for function 'clear_user_hexagon' [-Wmissing-prototypes]
     39 | unsigned long clear_user_hexagon(void __user *dest, unsigned long count)
        |               ^
  arch/hexagon/mm/uaccess.c:39:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
     39 | unsigned long clear_user_hexagon(void __user *dest, unsigned long count)
        | ^
        | static
  1 warning generated.

This function appears to have been unused since it was introduced in
commit 7567746e1c0d ("Hexagon: Add user access functions"), so remove it.

Link: https://lkml.kernel.org/r/20231130-hexagon-missing-prototypes-v1-0-5c34714afe9e@kernel.org
Link: https://lkml.kernel.org/r/20231130-hexagon-missing-prototypes-v1-1-5c34714afe9e@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brian Cain <bcain@quicinc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

arch: turn off -Werror for architectures with known warnings

A couple of architectures enable -Werror for their own files regardless of
CONFIG_WERROR but also have known warnings that fail the build with
-Wmissing-prototypes enabled by default:

arch/alpha/lib/memcpy.c:153:8: error: no previous prototype for 'memcpy' [-Werror=missing-prototypes]
arch/alpha/kernel/irq.c:96:1: error: no previous prototype for 'handle_irq' [-Werror=missing-prototypes]
arch/mips/kernel/signal.c:673:17: error: no previous prototype for ‘sys_rt_sigreturn’ [-Werror=missing-prototypes]
arch/mips/kernel/signal.c:636:17: error: no previous prototype for ‘sys_sigreturn’ [-Werror=missing-prototypes]
arch/mips/kernel/syscall.c:51:16: error: no previous prototype for ‘sysm_pipe’ [-Werror=missing-prototypes]
arch/mips/mm/fault.c:323:17: error: no previous prototype for ‘do_page_fault’ [-Werror=missing-prototypes]
arch/sparc/vdso/vma.c:246:12: warning: no previous prototype for ‘init_vdso_image’ [-Wmissing-prototypes]v
arch/sparc/vdso/vdso32/../vclock_gettime.c:343:1: warning: no previous prototype for ‘__vdso_gettimeofday_stick’ [-Wmissing-prototypes]
arch/sparc/vdso/vclock_gettime.c:343:1: warning: no previous prototype for ‘__vdso_gettimeofday_stick’ [-Wmissing-prototypes]
arch/sparc/prom/p1275.c:52:6: warning: no previous prototype for ‘prom_cif_init’ [-Wmissing-prototypes]
arch/sparc/prom/misc_64.c:165:5: warning: no previous prototype for ‘prom_get_mmu_ihandle’ [-Wmissing-prototypes]

This appears to be an artifact from the times when this architecture code
was better maintained that most device drivers and before CONFIG_WERROR
was added.  Now it just gets in the way, so remove all of these.

Powerpc and x86 both still have their own Kconfig options to enable
-Werror for some of their files.  These architectures are better
maintained than most and the options are easy to disable, so leave those
untouched.

Link: https://lkml.kernel.org/r/4be73872-c1f5-4c31-8201-712c19290a22@app.fastmail.com
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reported-by: Stephen Rothwell <sfr@rothwell.id.au>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

kexec: use atomic_try_cmpxchg in crash_kexec

Use atomic_try_cmpxchg instead of cmpxchg (*ptr, old, new) == old in
crash_kexec().  x86 CMPXCHG instruction returns success in ZF flag,
so this change saves a compare after cmpxchg.

No functional change intended.

Link: https://lkml.kernel.org/r/20231114161228.108516-1-ubizjak@gmail.com
Signed-off-by: Uros Bizjak <ubizjak@gmail.com>
Acked-by: Baoquan He <bhe@redhat.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

scripts/spelling.txt: add more spellings to spelling.txt

Some of the more common spelling mistakes and typos that I've found while
fixing up spelling mistakes in the kernel over the past couple of
releases.

Link: https://lkml.kernel.org/r/20231122104037.1770749-1-colin.i.king@gmail.com
Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

__ptrace_unlink: kill the obsolete "FIXME" code

The corner case described by the comment is no longer possible after the
commit 7b3c36fc4c23 ("ptrace: fix task_join_group_stop() for the case when
current is traced"), task_join_group_stop() ensures that the new thread
has the correct signr in JOBCTL_STOP_SIGMASK regardless of ptrace.

Link: https://lkml.kernel.org/r/20231121162650.GA6635@redhat.com
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

checkstack: allow to pass MINSTACKSIZE parameter

The checkstack script omits all functions with a stack usage of less than
100 bytes.  However the script already has support for a parameter which
allows to override the default, but it cannot be set with

$ make checkstack

Add a MINSTACKSIZE parameter which allows to change the default. This might
be useful in order to print the stack usage of all functions, or only those
with large stack usage:

$ make checkstack MINSTACKSIZE=0
$ make checkstack MINSTACKSIZE=800

Link: https://lkml.kernel.org/r/20231120183719.2188479-4-hca@linux.ibm.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Cc: Maninder Singh <maninder1.s@samsung.com>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Vaneet Narang <v.narang@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

checkstack: sort output by size and function name

Sort output by size and in addition by function name.  This increases
readability for cases where there are many functions with the same stack
usage.

Link: https://lkml.kernel.org/r/20231120183719.2188479-3-hca@linux.ibm.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Cc: Maninder Singh <maninder1.s@samsung.com>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Vaneet Narang <v.narang@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

kernel/signal.c: simplify force_sig_info_to_task(), kill recalc_sigpending_and_wake()

The purpose of recalc_sigpending_and_wake() is not clear, it looks
"obviously unneeded" because we are going to send the signal which can't
be blocked or ignored.

Add the comment to explain why we can't rely on send_signal_locked() and
make this logic more simple/explicit.  recalc_sigpending_and_wake() has no
other users, it can die.

In fact I think we don't even need signal_wake_up(), the target task must
be either current or a TASK_TRACED child, otherwise the usage of siglock
is not safe.  But this needs another change.

Link: https://lkml.kernel.org/r/20231120151649.GA15995@redhat.com
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

docs: filesystems: document the squashfs specific mount options

When SQUASHFS_CHOICE_DECOMP_BY_MOUNT is set, the "threads" mount option
can be used to specify the decompression mode: single-threaded,
multi-threaded, percpu or the number of threads used for decompression.
When SQUASHFS_CHOICE_DECOMP_BY_MOUNT is not set, SQUASHFS_DECOMP_MULTI and
SQUASHFS_MOUNT_DECOMP_THREADS are both set, the "threads" option can also
be used to specify the number of threads used for decompression.  This
mount option is only mentioned in fs/squashfs/Kconfig, which makes it
difficult to find.

Another mount option available is "errors", which can be configured to
panic the kernel when squashfs errors are encountered.

Add both these options to the squashfs documentation, making them more
noticeable.

Link: https://lkml.kernel.org/r/20231117161215.140282-1-amiculas@cisco.com
Signed-off-by: Ariel Miculas <amiculas@cisco.com>
Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com>
Reviewed-by: Phillip Lougher <phillip@squashfs.org.uk>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Serge Hallyn <serge@hallyn.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

checkpatch: do not require an empty line before error injection

ALLOW_ERROR_INJECTION macro (just like EXPORT_SYMBOL) can immediately
follow a function it annotates.

Link: https://lkml.kernel.org/r/20231109075147.2779461-1-senozhatsky@chromium.org
Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Acked-by: Joe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@canonical.com> (maintainer:CHECKPATCH)
Cc: Dwaipayan Ray <dwaipayanray1@gmail.com> (reviewer:CHECKPATCH)
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

arch: remove ARCH_TASK_STRUCT_ON_STACK

IA-64 was the only architecture which selected ARCH_TASK_STRUCT_ON_STACK.
IA-64 was removed with commit cf8e8658100d ("arch: Remove Itanium (IA-64)
architecture"). Therefore remove support for ARCH_TASK_STRUCT_ON_STACK
as well.

Note: this also reveals a potential bug in powerpc code, which makes use of
__init_task_data without selecting ARCH_TASK_STRUCT_ON_STACK which makes
__init_task_data a no-op. This is broken since commit d11ed3ab3166 ("Expand
INIT_TASK() in init/init_task.c and remove") from 2018 and needs to be
addressed separately.

Link: https://lkml.kernel.org/r/20231116133638.1636277-4-hca@linux.ibm.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

arch: remove ARCH_TASK_STRUCT_ALLOCATOR

IA-64 was the only architecture which selected ARCH_TASK_STRUCT_ALLOCATOR.
IA-64 was removed with commit cf8e8658100d ("arch: Remove Itanium (IA-64)
architecture"). Therefore remove support for ARCH_THREAD_STACK_ALLOCATOR
as well.

Link: https://lkml.kernel.org/r/20231116133638.1636277-3-hca@linux.ibm.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

arch: remove ARCH_THREAD_STACK_ALLOCATOR

Patch series "Remove unused code after IA-64 removal".

While looking into something different I noticed that there are a couple
of Kconfig options which were only selected by IA-64 and which are now
unused.

So remove them and simplify the code a bit.

This patch (of 3):

IA-64 was the only architecture which selected ARCH_THREAD_STACK_ALLOCATOR.
IA-64 was removed with commit cf8e8658100d ("arch: Remove Itanium (IA-64)
architecture"). Therefore remove support for ARCH_THREAD_STACK_ALLOCATOR as
well.

Link: https://lkml.kernel.org/r/20231116133638.1636277-1-hca@linux.ibm.com
Link: https://lkml.kernel.org/r/20231116133638.1636277-2-hca@linux.ibm.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

nilfs2: convert nilfs_btnode_abort_change_key to use a folio

Saves one call to compound_head().

Link: https://lkml.kernel.org/r/20231114084436.2755-21-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

nilfs2: convert nilfs_btnode_commit_change_key to use a folio

Saves one call to compound_head().

Link: https://lkml.kernel.org/r/20231114084436.2755-20-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

nilfs2: convert nilfs_btnode_prepare_change_key to use a folio

Saves three calls to compound_head().

Link: https://lkml.kernel.org/r/20231114084436.2755-19-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

nilfs2: convert nilfs_btnode_delete to use a folio

Saves six calls to compound_head().

Link: https://lkml.kernel.org/r/20231114084436.2755-18-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

nilfs2: convert nilfs_btnode_submit_block to use a folio

Saves two calls to compound_head().

Link: https://lkml.kernel.org/r/20231114084436.2755-17-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

nilfs2: convert nilfs_btnode_create_block to use a folio

Saves two calls to compound_head().

Link: https://lkml.kernel.org/r/20231114084436.2755-16-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

nilfs2: convert nilfs_gccache_submit_read_data to use a folio

Saves two calls to compound_head().

Link: https://lkml.kernel.org/r/20231114084436.2755-15-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

nilfs2: convert nilfs_mdt_submit_block to use a folio

Saves two calls to compound_head().

Link: https://lkml.kernel.org/r/20231114084436.2755-14-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

nilfs2: convert nilfs_mdt_create_block to use a folio

Saves two calls to compound_head().

Link: https://lkml.kernel.org/r/20231114084436.2755-13-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

nilfs2: convert nilfs_page_mkwrite() to use a folio

Using the new folio APIs saves seven hidden calls to compound_head().

Link: https://lkml.kernel.org/r/20231114084436.2755-12-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

nilfs2: convert nilfs_segctor_prepare_write to use folios

Use the new folio APIs, saving 17 hidden calls to compound_head().

Link: https://lkml.kernel.org/r/20231114084436.2755-11-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

nilfs2: convert to __nilfs_clear_folio_dirty()

All callers now have a folio, so convert to pass a folio.  No caller uses
the return value, so make it return void.  Removes a couple of hidden
calls to compound_head().

Link: https://lkml.kernel.org/r/20231114084436.2755-10-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

nilfs2: convert to nilfs_clear_folio_dirty()

All callers of nilfs_clear_dirty_page() now have a folio, so rename the
function and pass in the folio.  Saves three hidden calls to
compound_head().

Link: https://lkml.kernel.org/r/20231114084436.2755-9-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

nilfs2: convert nilfs_mdt_write_page() to use a folio

Convert the incoming page to a folio.  Replaces three calls to
compound_head() with one.

Link: https://lkml.kernel.org/r/20231114084436.2755-8-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

nilfs2: convert nilfs_writepage() to use a folio

Convert the incoming page to a folio.  Replaces three calls to
compound_head() with one.

Link: https://lkml.kernel.org/r/20231114084436.2755-7-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

nilfs2: convert to nilfs_folio_buffers_clean()

All callers of nilfs_page_buffers_clean() now have a folio, so convert it
to take a folio.  While I'm at it, make it return a bool.

Link: https://lkml.kernel.org/r/20231114084436.2755-6-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

nilfs2: convert nilfs_forget_buffer to use a folio

Save two hidden calls to compound_head().

Link: https://lkml.kernel.org/r/20231114084436.2755-5-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

nilfs2: convert nilfs_segctor_complete_write to use folios

Use the new folio APIs, saving five calls to compound_head().  This
includes the last callers of nilfs_end_page_io(), so remove that too.

Link: https://lkml.kernel.org/r/20231114084436.2755-4-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

nilfs2: convert nilfs_abort_logs to use folios

Use the new folio APIs, saving five hidden calls to compound_head().

Link: https://lkml.kernel.org/r/20231114084436.2755-3-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

nilfs2: add nilfs_end_folio_io()

Patch series "nilfs2: Folio conversions for file paths".

This series advances page->folio conversions for a wide range of nilfs2,
including its file operations, block routines, and the log writer's
writeback routines.  It doesn't cover large folios support, but it saves a
lot of hidden compound_head() calls while preserving the existing support
range behavior.

The original series in post [1] also covered directory-related page->folio
conversions, but that was put on hold because a regression was found in
testing, so this is an excerpt from the first half of the original post.

[1] https://lkml.kernel.org/r/20231106173903.1734114-1-willy@infradead.org

I tested this series in both 32-bit and 64-bit environments, switching
between normal and small block sizes.  I also reviewed all changes in all
patches to ensure they do not break existing behavior.  There were no
problems.

This patch (of 20):

This is the folio counterpart of the existing nilfs_end_page_io() which is
retained as a wrapper of nilfs_end_folio_io().  Replaces nine hidden calls
to compound_head() with one.

Link: https://lkml.kernel.org/r/20231114084436.2755-1-konishi.ryusuke@gmail.com
Link: https://lkml.kernel.org/r/20231114084436.2755-2-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Squashfs: fix variable overflow triggered by sysbot

Sysbot reports a slab out of bounds write in squashfs_readahead().

This is ultimately caused by a file reporting an (infeasibly) large file
size (1407374883553280 bytes) with the minimum block size of 4K.

This causes variable overflow.

Link: https://lkml.kernel.org/r/20231113160901.6444-1-phillip@squashfs.org.uk
Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk>
Reported-by: syzbot+604424eb051c2f696163@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/000000000000b1fda20609ede0d1@google.com/
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

fs/nilfs2: use standard array-copy-function

ioctl.c utilizes memdup_user() to copy a userspace array.  An overflow
check is performed manually before the function's invocation.

The new function memdup_array_user() standardizes copying userspace
arrays, thus, improving readability by making it more clear that an array
is being copied.  Additionally, it also performs an overflow check.

Remove the (now redundant) manual overflow-check and replace memdup_user()
with memdup_array_user().

In addition, improve the grammar of the comment above
memdup_array_user().

Link: https://lkml.kernel.org/r/20231106224416.3055-1-konishi.ryusuke@gmail.com
Signed-off-by: Philipp Stanner <pstanner@redhat.com>
Link: https://lkml.kernel.org/r/20231103184831.99406-2-pstanner@redhat.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Suggested-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

introduce for_other_threads(p, t)

Cosmetic, but imho it makes the usage look more clear and simple, the new
helper doesn't require to initialize "t".

After this change while_each_thread() has only 3 users, and it is only
used in the do/while loops.

Link: https://lkml.kernel.org/r/20231030155710.GA9095@redhat.com
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

kernel/reboot: explicitly notify if halt occurred instead of power off

When kernel_can_power_off() returns false, and reboot has called with
LINUX_REBOOT_CMD_POWER_OFF, kernel_halt() will be initiated instead of
actual power off function.

However, in this situation, Kernel never explicitly notifies user that
system halted instead of requested power off.

Since halt and power off perform different behavior, and user initiated
reboot call with power off command, not halt, This could be unintended
behavior to user, like this:

~ # poweroff -f
[    3.581482] reboot: System halted

Therefore, this explicitly notifies user that poweroff is not available,
and halting has been occured as an alternative behavior instead:

~ # poweroff -f
[    4.123668] reboot: Power off not available: System halted instead

[akpm@linux-foundation.org: tweak comment text]
Link: https://lkml.kernel.org/r/20231104113320.72440-1-ldmldm05@gmail.com
Signed-off-by: Dongmin Lee <ldmldm05@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Merge branch 'master' into mm-hotfixes-stable

mm/madvise: add cond_resched() in madvise_cold_or_pageout_pte_range()

I conducted real-time testing and observed that
madvise_cold_or_pageout_pte_range() causes significant latency under
memory pressure, which can be effectively reduced by adding cond_resched()
within the loop.

I tested on the LicheePi 4A board using Cylictest for latency testing and
Ftrace for latency tracing.  The board uses TH1520 processor and has a
memory size of 8GB.  The kernel version is 6.5.0 with the PREEMPT_RT patch
applied.

The script I tested is as follows:

echo wakeup_rt > /sys/kernel/tracing/current_tracer
echo 1 > /sys/kernel/tracing/tracing_on
echo 0 > /sys/kernel/tracing/tracing_max_latency
stress-ng --vm 8 --vm-bytes 2G &
cyclictest --mlockall --smp --priority=99 --distance=0 --duration=30m
echo 0 > /sys/kernel/tracing/tracing_on
cat /sys/kernel/tracing/trace

The tracing results before modification are as follows:

# tracer: wakeup_rt
#
# wakeup_rt latency trace v1.1.5 on 6.5.0-rt6-r1208-00003-g999d221864bf
# --------------------------------------------------------------------
# latency: 2552 us, #6/6, CPU#3 | (M:preempt_rt VP:0, KP:0, SP:0 HP:0 #P:4)
#    -----------------
#    | task: cyclictest-196 (uid:0 nice:0 policy:1 rt_prio:99)
#    -----------------
#
#                    _--------=> CPU#
#                   / _-------=> irqs-off/BH-disabled
#                  | / _------=> need-resched
#                  || / _-----=> need-resched-lazy
#                  ||| / _----=> hardirq/softirq
#                  |||| / _---=> preempt-depth
#                  ||||| / _--=> preempt-lazy-depth
#                  |||||| / _-=> migrate-disable
#                  ||||||| /     delay
#  cmd     pid     |||||||| time  |   caller
#     \   /        ||||||||  \    |    /
stress-n-206       3dn.h512    2us :      206:120:R   + [003]     196:  0:R cyclictest
stress-n-206       3dn.h512    7us : <stack trace>
 => __ftrace_trace_stack
 => __trace_stack
 => probe_wakeup
 => ttwu_do_activate
 => try_to_wake_up
 => wake_up_process
 => hrtimer_wakeup
 => __hrtimer_run_queues
 => hrtimer_interrupt
 => riscv_timer_interrupt
 => handle_percpu_devid_irq
 => generic_handle_domain_irq
 => riscv_intc_irq
 => handle_riscv_irq
 => do_irq
stress-n-206       3dn.h512    9us#: 0
stress-n-206       3d...3.. 2544us : __schedule
stress-n-206       3d...3.. 2545us :      206:120:R ==> [003]     196:  0:R cyclictest
stress-n-206       3d...3.. 2551us : <stack trace>
 => __ftrace_trace_stack
 => __trace_stack
 => probe_wakeup_sched_switch
 => __schedule
 => preempt_schedule
 => migrate_enable
 => rt_spin_unlock
 => madvise_cold_or_pageout_pte_range
 => walk_pgd_range
 => __walk_page_range
 => walk_page_range
 => madvise_pageout
 => madvise_vma_behavior
 => do_madvise
 => sys_madvise
 => do_trap_ecall_u
 => ret_from_exception

The tracing results after modification are as follows:

# tracer: wakeup_rt
#
# wakeup_rt latency trace v1.1.5 on 6.5.0-rt6-r1208-00004-gca3876fc69a6-dirty
# --------------------------------------------------------------------
# latency: 1689 us, #6/6, CPU#0 | (M:preempt_rt VP:0, KP:0, SP:0 HP:0 #P:4)
#    -----------------
#    | task: cyclictest-217 (uid:0 nice:0 policy:1 rt_prio:99)
#    -----------------
#
#                    _--------=> CPU#
#                   / _-------=> irqs-off/BH-disabled
#                  | / _------=> need-resched
#                  || / _-----=> need-resched-lazy
#                  ||| / _----=> hardirq/softirq
#                  |||| / _---=> preempt-depth
#                  ||||| / _--=> preempt-lazy-depth
#                  |||||| / _-=> migrate-disable
#                  ||||||| /     delay
#  cmd     pid     |||||||| time  |   caller
#     \   /        ||||||||  \    |    /
stress-n-232       0dn.h413    1us+:      232:120:R   + [000]     217:  0:R cyclictest
stress-n-232       0dn.h413   12us : <stack trace>
 => __ftrace_trace_stack
 => __trace_stack
 => probe_wakeup
 => ttwu_do_activate
 => try_to_wake_up
 => wake_up_process
 => hrtimer_wakeup
 => __hrtimer_run_queues
 => hrtimer_interrupt
 => riscv_timer_interrupt
 => handle_percpu_devid_irq
 => generic_handle_domain_irq
 => riscv_intc_irq
 => handle_riscv_irq
 => do_irq
stress-n-232       0dn.h413   19us#: 0
stress-n-232       0d...3.. 1671us : __schedule
stress-n-232       0d...3.. 1676us+:      232:120:R ==> [000]     217:  0:R cyclictest
stress-n-232       0d...3.. 1687us : <stack trace>
 => __ftrace_trace_stack
 => __trace_stack
 => probe_wakeup_sched_switch
 => __schedule
 => preempt_schedule
 => migrate_enable
 => free_unref_page_list
 => release_pages
 => free_pages_and_swap_cache
 => tlb_batch_pages_flush
 => tlb_flush_mmu
 => unmap_page_range
 => unmap_vmas
 => unmap_region
 => do_vmi_align_munmap.constprop.0
 => do_vmi_munmap
 => __vm_munmap
 => sys_munmap
 => do_trap_ecall_u
 => ret_from_exception

After the modification, the cause of maximum latency is no longer
madvise_cold_or_pageout_pte_range(), so this modification can reduce the
latency caused by madvise_cold_or_pageout_pte_range().

Currently the madvise_cold_or_pageout_pte_range() function exhibits
significant latency under memory pressure, which can be effectively
reduced by adding cond_resched() within the loop.

When the batch_count reaches SWAP_CLUSTER_MAX, we reschedule
the task to ensure fairness and avoid long lock holding times.

Link: https://lkml.kernel.org/r/85363861af65fac66c7a98c251906afc0d9c8098.1695291046.git.wangjiexun@tinylab.org
Signed-off-by: Jiexun Wang <wangjiexun@tinylab.org>
Cc: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

nilfs2: prevent WARNING in nilfs_sufile_set_segment_usage()

If nilfs2 reads a disk image with corrupted segment usage metadata, and
its segment usage information is marked as an error for the segment at the
write location, nilfs_sufile_set_segment_usage() can trigger WARN_ONs
during log writing.

Segments newly allocated for writing with nilfs_sufile_alloc() will not
have this error flag set, but this unexpected situation will occur if the
segment indexed by either nilfs->ns_segnum or nilfs->ns_nextnum (active
segment) was marked in error.

Fix this issue by inserting a sanity check to treat it as a file system
corruption.

Since error returns are not allowed during the execution phase where
nilfs_sufile_set_segment_usage() is used, this inserts the sanity check
into nilfs_sufile_mark_dirty() which pre-reads the buffer containing the
segment usage record to be updated and sets it up in a dirty state for
writing.

In addition, nilfs_sufile_set_segment_usage() is also called when
canceling log writing and undoing segment usage update, so in order to
avoid issuing the same kernel warning in that case, in case of
cancellation, avoid checking the error flag in
nilfs_sufile_set_segment_usage().

Link: https://lkml.kernel.org/r/20231205085947.4431-1-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Reported-by: syzbot+14e9f834f6ddecece094@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=14e9f834f6ddecece094
Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/hugetlb: have CONFIG_HUGETLB_PAGE select CONFIG_XARRAY_MULTI

After commit a08c7193e4f1 "mm/filemap: remove hugetlb special casing in
filemap.c", hugetlb pages are stored in the page cache in base page sized
indexes.  This leads to multi index stores in the xarray which is only
supporting through CONFIG_XARRAY_MULTI.  The other page cache user of
multi index stores ,THP, selects XARRAY_MULTI.  Have CONFIG_HUGETLB_PAGE
follow this behavior as well to avoid the BUG() with a CONFIG_HUGETLB_PAGE
&& !CONFIG_XARRAY_MULTI config.

Link: https://lkml.kernel.org/r/20231204183234.348697-1-sidhartha.kumar@oracle.com
Fixes: a08c7193e4f1 ("mm/filemap: remove hugetlb special casing in filemap.c")
Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Muchun Song <muchun.song@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

scripts/gdb: fix lx-device-list-bus and lx-device-list-class

After the conversion to bus_to_subsys() and class_to_subsys(), the gdb
scripts listing the system buses and classes respectively was broken, fix
those by returning the subsys_priv pointer and have the various caller
de-reference either the 'bus' or 'class' structure members accordingly.

Link: https://lkml.kernel.org/r/20231130043317.174188-1-florian.fainelli@broadcom.com
Fixes: 7b884b7f24b4 ("driver core: class.c: convert to only use class_to_subsys")
Signed-off-by: Florian Fainelli <florian.fainelli@broadcom.com>
Tested-by: Kuan-Ying Lee <Kuan-Ying.Lee@mediatek.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Kieran Bingham <kbingham@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

MAINTAINERS: drop Antti Palosaari

He is currently inactive (last message from him is two years ago [1]).
His media tree [2] is also dormant (latest activity is 6 years ago), yet
his site is still online [3].

Drop him from MAINTAINERS and add CREDITS entry for him. We thank him
for maintaining various DVB drivers.

[1]: https://lore.kernel.org/all/660772b3-0597-02db-ed94-c6a9be04e8e8@iki.fi/
[2]: https://git.linuxtv.org/anttip/media_tree.git/
[3]: https://palosaari.fi/linux/

Link: https://lkml.kernel.org/r/20231130083848.5396-1-bagasdotme@gmail.com
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Acked-by: Antti Palosaari <crope@iki.fi>
Cc: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

highmem: fix a memory copy problem in memcpy_from_folio

Clang static checker complains that value stored to 'from' is never read.
And memcpy_from_folio() only copy the last chunk memory from folio to
destination.  Use 'to += chunk' to replace 'from += chunk' to fix this
typo problem.

Link: https://lkml.kernel.org/r/20231130034017.1210429-1-suhui@nfschina.com
Fixes: b23d03ef7af5 ("highmem: add memcpy_to_folio() and memcpy_from_folio()")
Signed-off-by: Su Hui <suhui@nfschina.com>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Jiaqi Yan <jiaqiyan@google.com>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Cc: Tom Rix <trix@redhat.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

nilfs2: fix missing error check for sb_set_blocksize call

When mounting a filesystem image with a block size larger than the page
size, nilfs2 repeatedly outputs long error messages with stack traces to
the kernel log, such as the following:

 getblk(): invalid block size 8192 requested
 logical block size: 512
 ...
 Call Trace:
  dump_stack_lvl+0x92/0xd4
  dump_stack+0xd/0x10
  bdev_getblk+0x33a/0x354
  __breadahead+0x11/0x80
  nilfs_search_super_root+0xe2/0x704 [nilfs2]
  load_nilfs+0x72/0x504 [nilfs2]
  nilfs_mount+0x30f/0x518 [nilfs2]
  legacy_get_tree+0x1b/0x40
  vfs_get_tree+0x18/0xc4
  path_mount+0x786/0xa88
  __ia32_sys_mount+0x147/0x1a8
  __do_fast_syscall_32+0x56/0xc8
  do_fast_syscall_32+0x29/0x58
  do_SYSENTER_32+0x15/0x18
  entry_SYSENTER_32+0x98/0xf1
 ...

This overloads the system logger.  And to make matters worse, it sometimes
crashes the kernel with a memory access violation.

This is because the return value of the sb_set_blocksize() call, which
should be checked for errors, is not checked.

The latter issue is due to out-of-buffer memory being accessed based on a
large block size that caused sb_set_blocksize() to fail for buffers read
with the initial minimum block size that remained unupdated in the
super_block structure.

Since nilfs2 mkfs tool does not accept block sizes larger than the system
page size, this has been overlooked.  However, it is possible to create
this situation by intentionally modifying the tool or by passing a
filesystem image created on a system with a large page size to a system
with a smaller page size and mounting it.

Fix this issue by inserting the expected error handling for the call to
sb_set_blocksize().

Link: https://lkml.kernel.org/r/20231129141547.4726-1-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

kernel/Kconfig.kexec: drop select of KEXEC for CRASH_DUMP

Ignat Korchagin complained that a potential config regression was
introduced by commit 89cde455915f ("kexec: consolidate kexec and crash
options into kernel/Kconfig.kexec").  Before the commit, CONFIG_CRASH_DUMP
has no dependency on CONFIG_KEXEC.  After the commit, CRASH_DUMP selects
KEXEC.  That enforces system to have CONFIG_KEXEC=y as long as
CONFIG_CRASH_DUMP=Y which people may not want.

In Ignat's case, he sets CONFIG_CRASH_DUMP=y, CONFIG_KEXEC_FILE=y and
CONFIG_KEXEC=n because kexec_load interface could have security issue if
kernel/initrd has no chance to be signed and verified.

CRASH_DUMP has select of KEXEC because Eric, author of above commit, met a
LKP report of build failure when posting patch of earlier version.  Please
see below link to get detail of the LKP report:

    https://lore.kernel.org/all/3e8eecd1-a277-2cfb-690e-5de2eb7b988e@oracle.com/T/#u

In fact, that LKP report is triggered because arm's <asm/kexec.h> is
wrapped in CONFIG_KEXEC ifdeffery scope.  That is wrong.  CONFIG_KEXEC
controls the enabling/disabling of kexec_load interface, but not kexec
feature.  Removing the wrongly added CONFIG_KEXEC ifdeffery scope in
<asm/kexec.h> of arm allows us to drop the select KEXEC for CRASH_DUMP.
Meanwhile, change arch/arm/kernel/Makefile to let machine_kexec.o
relocate_kernel.o depend on KEXEC_CORE.

Link: https://lkml.kernel.org/r/20231128054457.659452-1-bhe@redhat.com
Fixes: 89cde455915f ("kexec: consolidate kexec and crash options into kernel/Kconfig.kexec")
Signed-off-by: Baoquan He <bhe@redhat.com>
Reported-by: Ignat Korchagin <ignat@cloudflare.com>
Tested-by: Ignat Korchagin <ignat@cloudflare.com> [compile-time only]
Tested-by: Alexander Gordeev <agordeev@linux.ibm.com>
Reviewed-by: Eric DeVolder <eric_devolder@yahoo.com>
Tested-by: Eric DeVolder <eric_devolder@yahoo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

units: add missing header

BITS_PER_BYTE is defined in bits.h.

Link: https://lkml.kernel.org/r/20231128174404.393393-1-andriy.shevchenko@linux.intel.com
Fixes: e8eed5f7366f ("units: Add BYTES_PER_*BIT")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Damian Muszynski <damian.muszynski@intel.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

drivers/base/cpu: crash data showing should depends on KEXEC_CORE

After commit 88a6f8994421 ("crash: memory and CPU hotplug sysfs
attributes"), on x86_64, if only below kernel configs related to kdump are
set, compiling error are triggered.

----
CONFIG_CRASH_CORE=y
CONFIG_KEXEC_CORE=y
CONFIG_CRASH_DUMP=y
CONFIG_CRASH_HOTPLUG=y
------

------------------------------------------------------
drivers/base/cpu.c: In function `crash_hotplug_show':
drivers/base/cpu.c:309:40: error: implicit declaration of function `crash_hotplug_cpu_support'; did you mean `crash_hotplug_show'? [-Werror=implicit-function-declaration]
  309 |         return sysfs_emit(buf, "%d\n", crash_hotplug_cpu_support());
      |                                        ^~~~~~~~~~~~~~~~~~~~~~~~~
      |                                        crash_hotplug_show
cc1: some warnings being treated as errors
------------------------------------------------------

CONFIG_KEXEC is used to enable kexec_load interface, the
crash_notes/crash_notes_size/crash_hotplug showing depends on
CONFIG_KEXEC is incorrect. It should depend on KEXEC_CORE instead.

Fix it now.

Link: https://lkml.kernel.org/r/20231128055248.659808-1-bhe@redhat.com
Fixes: 88a6f8994421 ("crash: memory and CPU hotplug sysfs attributes")
Signed-off-by: Baoquan He <bhe@redhat.com>
Tested-by: Ignat Korchagin <ignat@cloudflare.com> [compile-time only]
Tested-by: Alexander Gordeev <agordeev@linux.ibm.com>
Reviewed-by: Eric DeVolder <eric_devolder@yahoo.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/damon/sysfs-schemes: add timeout for update_schemes_tried_regions

If a scheme is set to not applied to any monitoring target region for any
reasons including the target access pattern, quota, filters, or
watermarks, writing 'update_schemes_tried_regions' to 'state' DAMON sysfs
file can indefinitely hang.  Fix the case by implementing a timeout for
the operation.  The time limit is two apply intervals of each scheme.

Link: https://lkml.kernel.org/r/20231124213840.39157-1-sj@kernel.org
Fixes: 4d4e41b68299 ("mm/damon/sysfs-schemes: do not update tried regions more than one DAMON snapshot")
Signed-off-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

scripts/gdb/tasks: fix lx-ps command error

Since commit 8e1f385104ac ("kill task_struct->thread_group") remove
the thread_group, we will encounter below issue.

(gdb) lx-ps
      TASK          PID    COMM
0xffff800086503340   0   swapper/0
Python Exception <class 'gdb.error'>: There is no member named thread_group.
Error occurred in Python: There is no member named thread_group.

We use signal->thread_head to iterate all threads instead.

[Kuan-Ying.Lee@mediatek.com: v2]
Link: https://lkml.kernel.org/r/20231129065142.13375-2-Kuan-Ying.Lee@mediatek.com
Link: https://lkml.kernel.org/r/20231127070404.4192-2-Kuan-Ying.Lee@mediatek.com
Fixes: 8e1f385104ac ("kill task_struct->thread_group")
Signed-off-by: Kuan-Ying Lee <Kuan-Ying.Lee@mediatek.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Tested-by: Florian Fainelli <florian.fainelli@broadcom.com>
Cc: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Cc: Chinwen Chang <chinwen.chang@mediatek.com>
Cc: Kuan-Ying Lee <Kuan-Ying.Lee@mediatek.com>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Qun-Wei Lin <qun-wei.lin@mediatek.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>