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| author | Josh Poimboeuf <jpoimboe@kernel.org> | 2024-06-25 23:02:00 -0700 |
|---|---|---|
| committer | Borislav Petkov (AMD) <bp@alien8.de> | 2024-06-28 15:23:38 +0200 |
| commit | 9142be9e6443fd641ca37f820efe00d9cd890eb1 (patch) | |
| tree | a1c5ddd81eab9c6cbb8d65ebbe40d73ddc5708ee /arch/x86/entry/syscall_64.c | |
| parent | Linux 6.10-rc5 (diff) | |
| download | linux-9142be9e6443fd641ca37f820efe00d9cd890eb1.tar.gz linux-9142be9e6443fd641ca37f820efe00d9cd890eb1.zip | |
x86/syscall: Mark exit[_group] syscall handlers __noreturn
The direct-call syscall dispatch function doesn't know that the exit()
and exit_group() syscall handlers don't return, so the call sites aren't
optimized accordingly.
Fix that by marking the exit syscall declarations __noreturn.
Fixes the following warnings:
vmlinux.o: warning: objtool: x64_sys_call+0x2804: __x64_sys_exit() is missing a __noreturn annotation
vmlinux.o: warning: objtool: ia32_sys_call+0x29b6: __ia32_sys_exit_group() is missing a __noreturn annotation
Fixes: 1e3ad78334a6 ("x86/syscall: Don't force use of indirect calls for system calls")
Closes: https://lkml.kernel.org/lkml/6dba9b32-db2c-4e6d-9500-7a08852f17a3@paulmck-laptop
Reported-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Tested-by: Paul E. McKenney <paulmck@kernel.org>
Link: https://lore.kernel.org/r/5d8882bc077d8eadcc7fd1740b56dfb781f12288.1719381528.git.jpoimboe@kernel.org
Diffstat (limited to 'arch/x86/entry/syscall_64.c')
| -rw-r--r-- | arch/x86/entry/syscall_64.c | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/arch/x86/entry/syscall_64.c b/arch/x86/entry/syscall_64.c index 33b3f09e6f15..ba8354424860 100644 --- a/arch/x86/entry/syscall_64.c +++ b/arch/x86/entry/syscall_64.c @@ -8,8 +8,12 @@ #include <asm/syscall.h> #define __SYSCALL(nr, sym) extern long __x64_##sym(const struct pt_regs *); +#define __SYSCALL_NORETURN(nr, sym) extern long __noreturn __x64_##sym(const struct pt_regs *); #include <asm/syscalls_64.h> -#undef __SYSCALL +#undef __SYSCALL + +#undef __SYSCALL_NORETURN +#define __SYSCALL_NORETURN __SYSCALL /* * The sys_call_table[] is no longer used for system calls, but @@ -20,10 +24,9 @@ const sys_call_ptr_t sys_call_table[] = { #include <asm/syscalls_64.h> }; -#undef __SYSCALL +#undef __SYSCALL #define __SYSCALL(nr, sym) case nr: return __x64_##sym(regs); - long x64_sys_call(const struct pt_regs *regs, unsigned int nr) { switch (nr) { |