diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2022-04-10 06:56:46 -1000 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2022-04-10 06:56:46 -1000 |
| commit | 50c94de67cfcf858d32a868dcc4e40d8581137c1 (patch) | |
| tree | 26f0f5e187a11359c2d0d0c379913e4ff632b281 /arch/x86 | |
| parent | 7136849ea95280685dc6a00a893501e61983b6b9 (diff) | |
| parent | 273ba85b5e8b971ed28eb5c17e1638543be9237d (diff) | |
Merge tag 'locking_urgent_for_v5.18_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking fixes from Borislav Petkov:
- Allow the compiler to optimize away unused percpu accesses and change
the local_lock_* macros back to inline functions
- A couple of fixes to static call insn patching
* tag 'locking_urgent_for_v5.18_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
Revert "mm/page_alloc: mark pagesets as __maybe_unused"
Revert "locking/local_lock: Make the empty local_lock_*() function a macro."
x86/percpu: Remove volatile from arch_raw_cpu_ptr().
static_call: Remove __DEFINE_STATIC_CALL macro
static_call: Properly initialise DEFINE_STATIC_CALL_RET0()
static_call: Don't make __static_call_return0 static
x86,static_call: Fix __static_call_return0 for i386
Diffstat (limited to 'arch/x86')
| -rw-r--r-- | arch/x86/include/asm/percpu.h | 6 | ||||
| -rw-r--r-- | arch/x86/include/asm/static_call.h | 2 | ||||
| -rw-r--r-- | arch/x86/kernel/static_call.c | 5 |
3 files changed, 7 insertions, 6 deletions
diff --git a/arch/x86/include/asm/percpu.h b/arch/x86/include/asm/percpu.h index a3c33b79fb86..13c0d63ed55e 100644 --- a/arch/x86/include/asm/percpu.h +++ b/arch/x86/include/asm/percpu.h @@ -38,9 +38,9 @@ #define arch_raw_cpu_ptr(ptr) \ ({ \ unsigned long tcp_ptr__; \ - asm volatile("add " __percpu_arg(1) ", %0" \ - : "=r" (tcp_ptr__) \ - : "m" (this_cpu_off), "0" (ptr)); \ + asm ("add " __percpu_arg(1) ", %0" \ + : "=r" (tcp_ptr__) \ + : "m" (this_cpu_off), "0" (ptr)); \ (typeof(*(ptr)) __kernel __force *)tcp_ptr__; \ }) #else diff --git a/arch/x86/include/asm/static_call.h b/arch/x86/include/asm/static_call.h index ed4f8bb6c2d9..2455d721503e 100644 --- a/arch/x86/include/asm/static_call.h +++ b/arch/x86/include/asm/static_call.h @@ -38,6 +38,8 @@ #define ARCH_DEFINE_STATIC_CALL_NULL_TRAMP(name) \ __ARCH_DEFINE_STATIC_CALL_TRAMP(name, "ret; int3; nop; nop; nop") +#define ARCH_DEFINE_STATIC_CALL_RET0_TRAMP(name) \ + ARCH_DEFINE_STATIC_CALL_TRAMP(name, __static_call_return0) #define ARCH_ADD_TRAMP_KEY(name) \ asm(".pushsection .static_call_tramp_key, \"a\" \n" \ diff --git a/arch/x86/kernel/static_call.c b/arch/x86/kernel/static_call.c index 531fb4cbb63f..aa72cefdd5be 100644 --- a/arch/x86/kernel/static_call.c +++ b/arch/x86/kernel/static_call.c @@ -12,10 +12,9 @@ enum insn_type { }; /* - * data16 data16 xorq %rax, %rax - a single 5 byte instruction that clears %rax - * The REX.W cancels the effect of any data16. + * cs cs cs xorl %eax, %eax - a single 5 byte instruction that clears %[er]ax */ -static const u8 xor5rax[] = { 0x66, 0x66, 0x48, 0x31, 0xc0 }; +static const u8 xor5rax[] = { 0x2e, 0x2e, 0x2e, 0x31, 0xc0 }; static const u8 retinsn[] = { RET_INSN_OPCODE, 0xcc, 0xcc, 0xcc, 0xcc }; |