From: Denys Vlasenko Date: Tue, 7 Apr 2015 20:43:44 +0000 (+0200) Subject: x86/asm/entry/64: Reduce padding in execve stubs X-Git-Tag: v4.1-rc1~182^2~5 X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=a37f34a325d90856314ccd4994e1070dcc6bdcc4;p=linux-block.git x86/asm/entry/64: Reduce padding in execve stubs execve stubs are 7 bytes only. Padding them to 16 bytes is a waste. text data bss dec hex filename 12594 0 0 12594 3132 entry_64.o.before 12530 0 0 12530 30f2 entry_64.o Run-tested. Signed-off-by: Denys Vlasenko Cc: Alexei Starovoitov Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Brian Gerst Cc: Frederic Weisbecker Cc: H. Peter Anvin Cc: Kees Cook Cc: Linus Torvalds Cc: Oleg Nesterov Cc: Steven Rostedt Cc: Thomas Gleixner Cc: Will Drewry Link: http://lkml.kernel.org/r/1428439424-7258-8-git-send-email-dvlasenk@redhat.com Signed-off-by: Ingo Molnar --- diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S index b67f2fc0d160..c7b238494b31 100644 --- a/arch/x86/kernel/entry_64.S +++ b/arch/x86/kernel/entry_64.S @@ -511,8 +511,12 @@ return_from_execve: jmp int_ret_from_sys_call CFI_ENDPROC END(stub_execve) - -ENTRY(stub_execveat) +/* + * Remaining execve stubs are only 7 bytes long. + * ENTRY() often aligns to 16 bytes, which in this case has no benefits. + */ + .align 8 +GLOBAL(stub_execveat) CFI_STARTPROC DEFAULT_FRAME 0, 8 call sys_execveat @@ -521,14 +525,16 @@ ENTRY(stub_execveat) END(stub_execveat) #ifdef CONFIG_X86_X32_ABI -ENTRY(stub_x32_execve) + .align 8 +GLOBAL(stub_x32_execve) CFI_STARTPROC DEFAULT_FRAME 0, 8 call compat_sys_execve jmp return_from_execve CFI_ENDPROC END(stub_x32_execve) -ENTRY(stub_x32_execveat) + .align 8 +GLOBAL(stub_x32_execveat) CFI_STARTPROC DEFAULT_FRAME 0, 8 call compat_sys_execveat @@ -538,13 +544,15 @@ END(stub_x32_execveat) #endif #ifdef CONFIG_IA32_EMULATION -ENTRY(stub32_execve) + .align 8 +GLOBAL(stub32_execve) CFI_STARTPROC call compat_sys_execve jmp return_from_execve CFI_ENDPROC END(stub32_execve) -ENTRY(stub32_execveat) + .align 8 +GLOBAL(stub32_execveat) CFI_STARTPROC call compat_sys_execveat jmp return_from_execve