objtool/idle: Validate __cpuidle code as noinstr
authorPeter Zijlstra <peterz@infradead.org>
Thu, 12 Jan 2023 19:43:31 +0000 (20:43 +0100)
committerIngo Molnar <mingo@kernel.org>
Fri, 13 Jan 2023 10:48:15 +0000 (11:48 +0100)
Idle code is very like entry code in that RCU isn't available. As
such, add a little validation.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Tony Lindgren <tony@atomide.com>
Tested-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/r/20230112195540.373461409@infradead.org
32 files changed:
arch/alpha/kernel/vmlinux.lds.S
arch/arc/kernel/vmlinux.lds.S
arch/arm/include/asm/vmlinux.lds.h
arch/arm64/kernel/vmlinux.lds.S
arch/csky/kernel/vmlinux.lds.S
arch/hexagon/kernel/vmlinux.lds.S
arch/ia64/kernel/vmlinux.lds.S
arch/loongarch/kernel/vmlinux.lds.S
arch/m68k/kernel/vmlinux-nommu.lds
arch/m68k/kernel/vmlinux-std.lds
arch/m68k/kernel/vmlinux-sun3.lds
arch/microblaze/kernel/vmlinux.lds.S
arch/mips/kernel/vmlinux.lds.S
arch/nios2/kernel/vmlinux.lds.S
arch/openrisc/kernel/vmlinux.lds.S
arch/parisc/kernel/vmlinux.lds.S
arch/powerpc/kernel/vmlinux.lds.S
arch/riscv/kernel/vmlinux-xip.lds.S
arch/riscv/kernel/vmlinux.lds.S
arch/s390/kernel/vmlinux.lds.S
arch/sh/kernel/vmlinux.lds.S
arch/sparc/kernel/vmlinux.lds.S
arch/um/kernel/dyn.lds.S
arch/um/kernel/uml.lds.S
arch/x86/include/asm/irqflags.h
arch/x86/include/asm/mwait.h
arch/x86/kernel/vmlinux.lds.S
arch/xtensa/kernel/vmlinux.lds.S
include/asm-generic/vmlinux.lds.h
include/linux/compiler_types.h
include/linux/cpu.h
tools/objtool/check.c

index 5b78d640725db85b9d416a5600876b79718436fd..2efa7dfc798a9577815244b68ee0da3bea316d06 100644 (file)
@@ -27,7 +27,6 @@ SECTIONS
                HEAD_TEXT
                TEXT_TEXT
                SCHED_TEXT
-               CPUIDLE_TEXT
                LOCK_TEXT
                *(.fixup)
                *(.gnu.warning)
index 529ae50f9fe23ced655e9dbf72a4914761ef02d9..549c3f407918693f4407e4b0854cdd63d2017952 100644 (file)
@@ -85,7 +85,6 @@ SECTIONS
                _stext = .;
                TEXT_TEXT
                SCHED_TEXT
-               CPUIDLE_TEXT
                LOCK_TEXT
                KPROBES_TEXT
                IRQENTRY_TEXT
index fad45c884e98890b4958ec9f71d377d14b0d4173..4c8632d5c432c3c7e9351ebae65a90ee9a4c31db 100644 (file)
@@ -96,7 +96,6 @@
                SOFTIRQENTRY_TEXT                                       \
                TEXT_TEXT                                               \
                SCHED_TEXT                                              \
-               CPUIDLE_TEXT                                            \
                LOCK_TEXT                                               \
                KPROBES_TEXT                                            \
                ARM_STUBS_TEXT                                          \
index 4c13dafc98b8400f51468c880a2513242b65b669..2777214cbf1a4d76e823cffa6b37a051fdaf9af2 100644 (file)
@@ -175,7 +175,6 @@ SECTIONS
                        ENTRY_TEXT
                        TEXT_TEXT
                        SCHED_TEXT
-                       CPUIDLE_TEXT
                        LOCK_TEXT
                        KPROBES_TEXT
                        HYPERVISOR_TEXT
index 68c980d084829adedd9205d6dbb29166f7f6dcd6..d718961786d246b3049f91b877d88a85bd880883 100644 (file)
@@ -34,7 +34,6 @@ SECTIONS
                SOFTIRQENTRY_TEXT
                TEXT_TEXT
                SCHED_TEXT
-               CPUIDLE_TEXT
                LOCK_TEXT
                KPROBES_TEXT
                *(.fixup)
index 57465bff1fe49717cbf0b68280bae499e337b9d7..1140051a0c455d07cc2db9fccfe7b4cf10256671 100644 (file)
@@ -41,7 +41,6 @@ SECTIONS
                IRQENTRY_TEXT
                SOFTIRQENTRY_TEXT
                SCHED_TEXT
-               CPUIDLE_TEXT
                LOCK_TEXT
                KPROBES_TEXT
                *(.fixup)
index 9b265783be6a193d6a341e3a60308d16ce1cb5fe..53dfde161c8ab1e19eaa9c5986c453e3fc4f64db 100644 (file)
@@ -51,7 +51,6 @@ SECTIONS {
                __end_ivt_text = .;
                TEXT_TEXT
                SCHED_TEXT
-               CPUIDLE_TEXT
                LOCK_TEXT
                KPROBES_TEXT
                IRQENTRY_TEXT
index 733b16e8d55ddb55d3142cf7ccd02287c158c85f..78506b31ba61babffa2238b5b891652f078ed741 100644 (file)
@@ -43,7 +43,6 @@ SECTIONS
        .text : {
                TEXT_TEXT
                SCHED_TEXT
-               CPUIDLE_TEXT
                LOCK_TEXT
                KPROBES_TEXT
                IRQENTRY_TEXT
index 387f334e87d3ecc1daa1df0fd6bbe3f11679bbf5..2624fc18c131f1896d1983aec1aaab2b35e5ae68 100644 (file)
@@ -48,7 +48,6 @@ SECTIONS {
                IRQENTRY_TEXT
                SOFTIRQENTRY_TEXT
                SCHED_TEXT
-               CPUIDLE_TEXT
                LOCK_TEXT
                *(.fixup)
                . = ALIGN(16);
index ed1d9eda319083f4ceca0aed8c53bc18fe8fe6ef..1ccdd04ae46242ead1d2e98be8e9c48f17340345 100644 (file)
@@ -19,7 +19,6 @@ SECTIONS
        IRQENTRY_TEXT
        SOFTIRQENTRY_TEXT
        SCHED_TEXT
-       CPUIDLE_TEXT
        LOCK_TEXT
        *(.fixup)
        *(.gnu.warning)
index 4a52f44f2ef07fc64927c5888ccff0c6f5287567..f13ddcc2af5c280f7505752d421b679e4846930a 100644 (file)
@@ -19,7 +19,6 @@ SECTIONS
        IRQENTRY_TEXT
        SOFTIRQENTRY_TEXT
        SCHED_TEXT
-       CPUIDLE_TEXT
        LOCK_TEXT
        *(.fixup)
        *(.gnu.warning)
index fb31747ec092b898383f496209c0a945cab71f4c..ae50d3d04a7dd607453906d9b851bdd38e5106ce 100644 (file)
@@ -36,7 +36,6 @@ SECTIONS {
                EXIT_TEXT
                EXIT_CALL
                SCHED_TEXT
-               CPUIDLE_TEXT
                LOCK_TEXT
                KPROBES_TEXT
                IRQENTRY_TEXT
index 1f98947fe715daca0f6a68b11e1ecd1a3d7647a8..52cbde60edf5b1b780b0ba30666aca3df4196b96 100644 (file)
@@ -61,7 +61,6 @@ SECTIONS
        .text : {
                TEXT_TEXT
                SCHED_TEXT
-               CPUIDLE_TEXT
                LOCK_TEXT
                KPROBES_TEXT
                IRQENTRY_TEXT
index 126e114744cb9c7785264b237cba94e9af048a65..37b9580550646974af780836c6d4b5daadf19070 100644 (file)
@@ -24,7 +24,6 @@ SECTIONS
        .text : {
                TEXT_TEXT
                SCHED_TEXT
-               CPUIDLE_TEXT
                LOCK_TEXT
                IRQENTRY_TEXT
                SOFTIRQENTRY_TEXT
index d5c7bb0fae579f91e725671915c8bd709fabea1e..bc13060478373d785f07305adc2b321e9ffb1ac3 100644 (file)
@@ -52,7 +52,6 @@ SECTIONS
           _stext = .;
          TEXT_TEXT
          SCHED_TEXT
-         CPUIDLE_TEXT
          LOCK_TEXT
          KPROBES_TEXT
          IRQENTRY_TEXT
index 2769eb991f58d120f52bf905dcc96b81f0b556b4..1aaa2ca0980033d337597b9c8b2f14bea36c628e 100644 (file)
@@ -86,7 +86,6 @@ SECTIONS
                TEXT_TEXT
                LOCK_TEXT
                SCHED_TEXT
-               CPUIDLE_TEXT
                KPROBES_TEXT
                IRQENTRY_TEXT
                SOFTIRQENTRY_TEXT
index 8c3862b4c259d6a2b89d40cfd712ce4d2f974179..86d5ca19a5402e83e8060550b490679152a4698c 100644 (file)
@@ -111,7 +111,6 @@ SECTIONS
 #endif
                NOINSTR_TEXT
                SCHED_TEXT
-               CPUIDLE_TEXT
                LOCK_TEXT
                KPROBES_TEXT
                IRQENTRY_TEXT
index 75e0fa8a700ae62c92ddce41a572b7876a0f24ed..eab9edc3b63147ec0d1205d0fde92989c5669cd5 100644 (file)
@@ -39,7 +39,6 @@ SECTIONS
                _stext = .;
                TEXT_TEXT
                SCHED_TEXT
-               CPUIDLE_TEXT
                LOCK_TEXT
                KPROBES_TEXT
                ENTRY_TEXT
index 4e6c88aa4d87049c9bba77c0379491e2a5ae222f..643ab60e9efb0c04e14f3b7450362d9a84dea2c3 100644 (file)
@@ -42,7 +42,6 @@ SECTIONS
                _stext = .;
                TEXT_TEXT
                SCHED_TEXT
-               CPUIDLE_TEXT
                LOCK_TEXT
                KPROBES_TEXT
                ENTRY_TEXT
index 5ea3830af0ccff11c6a18a06a2392cf690742b34..d1f1ab2979951acf2d67043519c9756a07e5a47c 100644 (file)
@@ -42,7 +42,6 @@ SECTIONS
                HEAD_TEXT
                TEXT_TEXT
                SCHED_TEXT
-               CPUIDLE_TEXT
                LOCK_TEXT
                KPROBES_TEXT
                IRQENTRY_TEXT
index 3161b9ccd2a5707e6c039c30c9f05c6708bd76b6..947e2e213ff9916d73cf63d63e54b26a1048024d 100644 (file)
@@ -29,7 +29,6 @@ SECTIONS
                HEAD_TEXT
                TEXT_TEXT
                SCHED_TEXT
-               CPUIDLE_TEXT
                LOCK_TEXT
                KPROBES_TEXT
                IRQENTRY_TEXT
index d55ae65a07adfda3a9543ce358472c981f5abfe5..d317a843f7ea9b168b6824a7c7a9b99c8c812c3a 100644 (file)
@@ -50,7 +50,6 @@ SECTIONS
                HEAD_TEXT
                TEXT_TEXT
                SCHED_TEXT
-               CPUIDLE_TEXT
                LOCK_TEXT
                KPROBES_TEXT
                IRQENTRY_TEXT
index 2b7fc5b54164881073e27faec51c27610fa61620..3385d653ebd0d04f5a342adb4b47affabcb0cfab 100644 (file)
@@ -74,7 +74,6 @@ SECTIONS
     _stext = .;
     TEXT_TEXT
     SCHED_TEXT
-    CPUIDLE_TEXT
     LOCK_TEXT
     IRQENTRY_TEXT
     SOFTIRQENTRY_TEXT
index 71a59b8adbdca3b309c497a3c1d95be610644199..5c92d58a78e89cc940c77162a96b6433bc1078e4 100644 (file)
@@ -35,7 +35,6 @@ SECTIONS
     _stext = .;
     TEXT_TEXT
     SCHED_TEXT
-    CPUIDLE_TEXT
     LOCK_TEXT
     IRQENTRY_TEXT
     SOFTIRQENTRY_TEXT
index 7793e52d6237a42279c716e2b1b94d3fa03e48a6..8c5ae649d2df82999815998c5ba92ba044dfbea9 100644 (file)
@@ -8,9 +8,6 @@
 
 #include <asm/nospec-branch.h>
 
-/* Provide __cpuidle; we can't safely include <linux/cpu.h> */
-#define __cpuidle __section(".cpuidle.text")
-
 /*
  * Interrupt control:
  */
@@ -45,13 +42,13 @@ static __always_inline void native_irq_enable(void)
        asm volatile("sti": : :"memory");
 }
 
-static inline __cpuidle void native_safe_halt(void)
+static __always_inline void native_safe_halt(void)
 {
        mds_idle_clear_cpu_buffers();
        asm volatile("sti; hlt": : :"memory");
 }
 
-static inline __cpuidle void native_halt(void)
+static __always_inline void native_halt(void)
 {
        mds_idle_clear_cpu_buffers();
        asm volatile("hlt": : :"memory");
@@ -84,7 +81,7 @@ static __always_inline void arch_local_irq_enable(void)
  * Used in the idle loop; sti takes one instruction cycle
  * to complete:
  */
-static inline __cpuidle void arch_safe_halt(void)
+static __always_inline void arch_safe_halt(void)
 {
        native_safe_halt();
 }
@@ -93,7 +90,7 @@ static inline __cpuidle void arch_safe_halt(void)
  * Used when interrupts are already enabled or to
  * shutdown the processor:
  */
-static inline __cpuidle void halt(void)
+static __always_inline void halt(void)
 {
        native_halt();
 }
index 3a8fdf881313d8aad8d722e592db34b0d651f72a..f2242167efe3f6f19b94904bab76e8dc5d0dbd1f 100644 (file)
@@ -105,7 +105,7 @@ static inline void __sti_mwait(unsigned long eax, unsigned long ecx)
  * New with Core Duo processors, MWAIT can take some hints based on CPU
  * capability.
  */
-static inline void mwait_idle_with_hints(unsigned long eax, unsigned long ecx)
+static __always_inline void mwait_idle_with_hints(unsigned long eax, unsigned long ecx)
 {
        if (static_cpu_has_bug(X86_BUG_MONITOR) || !current_set_polling_and_test()) {
                if (static_cpu_has_bug(X86_BUG_CLFLUSH_MONITOR)) {
index 2e0ee14229bffce61924e7d1b689864f728eda5b..25f155205770c7d6286e345a70c77a3159599621 100644 (file)
@@ -129,7 +129,6 @@ SECTIONS
                HEAD_TEXT
                TEXT_TEXT
                SCHED_TEXT
-               CPUIDLE_TEXT
                LOCK_TEXT
                KPROBES_TEXT
                SOFTIRQENTRY_TEXT
index 965a3952c47b8994ed08c4be199e24299a777102..c14fd96f459d65b76bf10552c7202d05e0cf5805 100644 (file)
@@ -125,7 +125,6 @@ SECTIONS
     ENTRY_TEXT
     TEXT_TEXT
     SCHED_TEXT
-    CPUIDLE_TEXT
     LOCK_TEXT
     *(.fixup)
   }
index a94219e9916f185acef402efca6538503a1c7680..ad0d39403cf2245f3d27ac514606c26feece19a8 100644 (file)
                ALIGN_FUNCTION();                                       \
                __noinstr_text_start = .;                               \
                *(.noinstr.text)                                        \
+               __cpuidle_text_start = .;                               \
+               *(.cpuidle.text)                                        \
+               __cpuidle_text_end = .;                                 \
                __noinstr_text_end = .;
 
 /*
                *(.spinlock.text)                                       \
                __lock_text_end = .;
 
-#define CPUIDLE_TEXT                                                   \
-               ALIGN_FUNCTION();                                       \
-               __cpuidle_text_start = .;                               \
-               *(.cpuidle.text)                                        \
-               __cpuidle_text_end = .;
-
 #define KPROBES_TEXT                                                   \
                ALIGN_FUNCTION();                                       \
                __kprobes_text_start = .;                               \
index 7c1afe0f4129c5a5f76de071a68d41c41e3e1353..d7858901f03550c3411fb57c452554ee900b17a6 100644 (file)
@@ -232,11 +232,15 @@ struct ftrace_likely_data {
 #endif
 
 /* Section for code which can't be instrumented at all */
-#define noinstr                                                                \
-       noinline notrace __attribute((__section__(".noinstr.text")))    \
+#define __noinstr_section(section)                                     \
+       noinline notrace __attribute((__section__(section)))            \
        __no_kcsan __no_sanitize_address __no_profile __no_sanitize_coverage \
        __no_sanitize_memory
 
+#define noinstr __noinstr_section(".noinstr.text")
+
+#define __cpuidle __noinstr_section(".cpuidle.text")
+
 #endif /* __KERNEL__ */
 
 #endif /* __ASSEMBLY__ */
index 314802f98b9daadf3b0d7cf346fa0722b50a5b7a..f83e4519c5f05407ce87992f4afefad2f6f0c196 100644 (file)
@@ -176,9 +176,6 @@ void __noreturn cpu_startup_entry(enum cpuhp_state state);
 
 void cpu_idle_poll_ctrl(bool enable);
 
-/* Attach to any functions which should be considered cpuidle. */
-#define __cpuidle      __section(".cpuidle.text")
-
 bool cpu_in_idle(unsigned long pc);
 
 void arch_cpu_idle(void);
index 4350be739f4fac504657fe76d4b8c93da1d244b7..64954aa83522dcd4bdc732d2b18fdad26246ebba 100644 (file)
@@ -376,6 +376,7 @@ static int decode_instructions(struct objtool_file *file)
 
                if (!strcmp(sec->name, ".noinstr.text") ||
                    !strcmp(sec->name, ".entry.text") ||
+                   !strcmp(sec->name, ".cpuidle.text") ||
                    !strncmp(sec->name, ".text.__x86.", 12))
                        sec->noinstr = true;
 
@@ -3365,6 +3366,12 @@ static inline bool noinstr_call_dest(struct objtool_file *file,
        if (func->sec->noinstr)
                return true;
 
+       /*
+        * If the symbol is a static_call trampoline, we can't tell.
+        */
+       if (func->static_call_tramp)
+               return true;
+
        /*
         * The __ubsan_handle_*() calls are like WARN(), they only happen when
         * something 'BAD' happened. At the risk of taking the machine down,
@@ -4162,6 +4169,12 @@ static int validate_noinstr_sections(struct objtool_file *file)
                warnings += validate_unwind_hints(file, sec);
        }
 
+       sec = find_section_by_name(file->elf, ".cpuidle.text");
+       if (sec) {
+               warnings += validate_section(file, sec);
+               warnings += validate_unwind_hints(file, sec);
+       }
+
        return warnings;
 }