diff options
| author | Denys Vlasenko <[email protected]> | 2015-04-07 22:43:44 +0200 |
|---|---|---|
| committer | Ingo Molnar <[email protected]> | 2015-04-09 10:31:26 +0200 |
| commit | a37f34a325d90856314ccd4994e1070dcc6bdcc4 (patch) | |
| tree | 9761bec624da40a90c0dfd7b2732fbdd8c9cdec2 | |
| parent | 54a81e914b2432a86dd49cf611b0f71ef44ca7ad (diff) | |
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 <[email protected]>
Cc: Alexei Starovoitov <[email protected]>
Cc: Andy Lutomirski <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Brian Gerst <[email protected]>
Cc: Frederic Weisbecker <[email protected]>
Cc: H. Peter Anvin <[email protected]>
Cc: Kees Cook <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Oleg Nesterov <[email protected]>
Cc: Steven Rostedt <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Will Drewry <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
| -rw-r--r-- | arch/x86/kernel/entry_64.S | 20 |
1 files changed, 14 insertions, 6 deletions
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 |