Commit e990c77d authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 

* 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86-64, asm: If the assembler supports fxsave64, use it
  i386: Make kernel_execve() suitable for stack unwinding
parents 2f0384e5 d7acb92f

arch/x86/Makefile

+6 −2
Original line number Diff line number Diff line
@@ -96,8 +96,12 @@ cfi := $(call as-instr,.cfi_startproc\n.cfi_rel_offset $(sp-y)$(comma)0\n.cfi_en 
# is .cfi_signal_frame supported too?

cfi-sigframe := $(call as-instr,.cfi_startproc\n.cfi_signal_frame\n.cfi_endproc,-DCONFIG_AS_CFI_SIGNAL_FRAME=1)

cfi-sections := $(call as-instr,.cfi_sections .debug_frame,-DCONFIG_AS_CFI_SECTIONS=1)

KBUILD_AFLAGS += $(cfi) $(cfi-sigframe) $(cfi-sections)

KBUILD_CFLAGS += $(cfi) $(cfi-sigframe) $(cfi-sections)



# does binutils support specific instructions?

asinstr := $(call as-instr,fxsaveq (%rax),-DCONFIG_AS_FXSAVEQ=1)



KBUILD_AFLAGS += $(cfi) $(cfi-sigframe) $(cfi-sections) $(asinstr)

KBUILD_CFLAGS += $(cfi) $(cfi-sigframe) $(cfi-sections) $(asinstr)



LDFLAGS := -m elf_$(UTS_MACHINE)

arch/x86/include/asm/i387.h

+1 −1
Original line number Diff line number Diff line
@@ -175,7 +175,7 @@ static inline void fpu_fxsave(struct fpu *fpu) 
	   uses any extended registers for addressing, a second REX prefix

	   will be generated (to the assembler, rex64 followed by semicolon

	   is a separate instruction), and hence the 64-bitness is lost. */

#if 0

#ifdef CONFIG_AS_FXSAVEQ

	/* Using "fxsaveq %0" would be the ideal choice, but is only supported

	   starting with gas 2.16. */

	__asm__ __volatile__("fxsaveq %0"

arch/x86/kernel/sys_i386_32.c

+2 −2
Original line number Diff line number Diff line
@@ -33,8 +33,8 @@ int kernel_execve(const char *filename, 
		  const char *const envp[])

{

	long __res;

	asm volatile ("push %%ebx ; movl %2,%%ebx ; int $0x80 ; pop %%ebx"

	asm volatile ("int $0x80"

	: "=a" (__res)

	: "0" (__NR_execve), "ri" (filename), "c" (argv), "d" (envp) : "memory");

	: "0" (__NR_execve), "b" (filename), "c" (argv), "d" (envp) : "memory");

	return __res;

}