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Revert "x86/cpufeature: Macrofy inline assembly code to work around GCC inlining bugs"

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This reverts commit d5a581d84ae6b8a4a740464b80d8d9cf1e7947b2.

See this commit for details about the revert:

  e769742d3584 ("Revert "x86/jump-labels: Macrofy inline assembly code to work around GCC inlining bugs"")

Reported-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Borislav Petkov <bp@alien8.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Juergen Gross <jgross@suse.com>
Cc: Richard Biener <rguenther@suse.de>
Cc: Kees Cook <keescook@chromium.org>
Cc: Segher Boessenkool <segher@kernel.crashing.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Nadav Amit <namit@vmware.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Ingo Molnar 2018-12-19 11:20:30 +01:00
parent e769742d35
commit c3462ba986
2 changed files with 35 additions and 48 deletions
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82
arch/x86/include/asm/cpufeature.h
View File

@ -2,10 +2,10 @@
#ifndef _ASM_X86_CPUFEATURE_H
#define _ASM_X86_CPUFEATURE_H
#ifdef __KERNEL__
#ifndef __ASSEMBLY__
#include <asm/processor.h>
#if defined(__KERNEL__) && !defined(__ASSEMBLY__)
#include <asm/asm.h>
#include <linux/bitops.h>
@ -161,10 +161,37 @@ extern void clear_cpu_cap(struct cpuinfo_x86 *c, unsigned int bit);
*/
static __always_inline __pure bool _static_cpu_has(u16 bit)
{
asm_volatile_goto("STATIC_CPU_HAS bitnum=%[bitnum] "
"cap_byte=\"%[cap_byte]\" "
"feature=%P[feature] t_yes=%l[t_yes] "
"t_no=%l[t_no] always=%P[always]"
asm_volatile_goto("1: jmp 6f\n"
"2:\n"
".skip -(((5f-4f) - (2b-1b)) > 0) * "
"((5f-4f) - (2b-1b)),0x90\n"
"3:\n"
".section .altinstructions,\"a\"\n"
" .long 1b - .\n" /* src offset */
" .long 4f - .\n" /* repl offset */
" .word %P[always]\n" /* always replace */
" .byte 3b - 1b\n" /* src len */
" .byte 5f - 4f\n" /* repl len */
" .byte 3b - 2b\n" /* pad len */
".previous\n"
".section .altinstr_replacement,\"ax\"\n"
"4: jmp %l[t_no]\n"
"5:\n"
".previous\n"
".section .altinstructions,\"a\"\n"
" .long 1b - .\n" /* src offset */
" .long 0\n" /* no replacement */
" .word %P[feature]\n" /* feature bit */
" .byte 3b - 1b\n" /* src len */
" .byte 0\n" /* repl len */
" .byte 0\n" /* pad len */
".previous\n"
".section .altinstr_aux,\"ax\"\n"
"6:\n"
" testb %[bitnum],%[cap_byte]\n"
" jnz %l[t_yes]\n"
" jmp %l[t_no]\n"
".previous\n"
: : [feature] "i" (bit),
[always] "i" (X86_FEATURE_ALWAYS),
[bitnum] "i" (1 << (bit & 7)),
@ -199,44 +226,5 @@ t_no:
#define CPU_FEATURE_TYPEVAL boot_cpu_data.x86_vendor, boot_cpu_data.x86, \
boot_cpu_data.x86_model
#else /* __ASSEMBLY__ */
.macro STATIC_CPU_HAS bitnum:req cap_byte:req feature:req t_yes:req t_no:req always:req
1:
jmp 6f
2:
.skip -(((5f-4f) - (2b-1b)) > 0) * ((5f-4f) - (2b-1b)),0x90
3:
.section .altinstructions,"a"
.long 1b - . /* src offset */
.long 4f - . /* repl offset */
.word \always /* always replace */
.byte 3b - 1b /* src len */
.byte 5f - 4f /* repl len */
.byte 3b - 2b /* pad len */
.previous
.section .altinstr_replacement,"ax"
4:
jmp \t_no
5:
.previous
.section .altinstructions,"a"
.long 1b - . /* src offset */
.long 0 /* no replacement */
.word \feature /* feature bit */
.byte 3b - 1b /* src len */
.byte 0 /* repl len */
.byte 0 /* pad len */
.previous
.section .altinstr_aux,"ax"
6:
testb \bitnum,\cap_byte
jnz \t_yes
jmp \t_no
.previous
.endm
#endif /* __ASSEMBLY__ */
#endif /* __KERNEL__ */
#endif /* defined(__KERNEL__) && !defined(__ASSEMBLY__) */
#endif /* _ASM_X86_CPUFEATURE_H */

1
arch/x86/kernel/macros.S
View File

@ -12,4 +12,3 @@
#include <asm/bug.h>
#include <asm/paravirt.h>
#include <asm/asm.h>
#include <asm/cpufeature.h>