diff options
| -rw-r--r-- | arch/x86/Makefile | 1 | ||||
| -rw-r--r-- | arch/x86/include/asm/fpu/internal.h | 50 | ||||
| -rw-r--r-- | arch/x86/kernel/traps.c | 5 |
3 files changed, 8 insertions, 48 deletions
diff --git a/arch/x86/Makefile b/arch/x86/Makefile index 9c5a67d1b9c1..76bc4dc03d5e 100644 --- a/arch/x86/Makefile +++ b/arch/x86/Makefile @@ -187,7 +187,6 @@ cfi-sigframe := $(call as-instr,.cfi_startproc\n.cfi_signal_frame\n.cfi_endproc, cfi-sections := $(call as-instr,.cfi_sections .debug_frame,-DCONFIG_AS_CFI_SECTIONS=1) # does binutils support specific instructions? -asinstr := $(call as-instr,fxsaveq (%rax),-DCONFIG_AS_FXSAVEQ=1) asinstr += $(call as-instr,pshufb %xmm0$(comma)%xmm0,-DCONFIG_AS_SSSE3=1) avx_instr := $(call as-instr,vxorps %ymm0$(comma)%ymm1$(comma)%ymm2,-DCONFIG_AS_AVX=1) avx2_instr :=$(call as-instr,vpbroadcastb %xmm0$(comma)%ymm1,-DCONFIG_AS_AVX2=1) diff --git a/arch/x86/include/asm/fpu/internal.h b/arch/x86/include/asm/fpu/internal.h index fa2c93cb42a2..5d536e3dcc6d 100644 --- a/arch/x86/include/asm/fpu/internal.h +++ b/arch/x86/include/asm/fpu/internal.h @@ -137,37 +137,25 @@ static inline int copy_fxregs_to_user(struct fxregs_state __user *fx) { if (IS_ENABLED(CONFIG_X86_32)) return user_insn(fxsave %[fx], [fx] "=m" (*fx), "m" (*fx)); - else if (IS_ENABLED(CONFIG_AS_FXSAVEQ)) + else return user_insn(fxsaveq %[fx], [fx] "=m" (*fx), "m" (*fx)); - /* See comment in copy_fxregs_to_kernel() below. */ - return user_insn(rex64/fxsave (%[fx]), "=m" (*fx), [fx] "R" (fx)); } static inline void copy_kernel_to_fxregs(struct fxregs_state *fx) { - if (IS_ENABLED(CONFIG_X86_32)) { + if (IS_ENABLED(CONFIG_X86_32)) kernel_insn(fxrstor %[fx], "=m" (*fx), [fx] "m" (*fx)); - } else { - if (IS_ENABLED(CONFIG_AS_FXSAVEQ)) { - kernel_insn(fxrstorq %[fx], "=m" (*fx), [fx] "m" (*fx)); - } else { - /* See comment in copy_fxregs_to_kernel() below. */ - kernel_insn(rex64/fxrstor (%[fx]), "=m" (*fx), [fx] "R" (fx), "m" (*fx)); - } - } + else + kernel_insn(fxrstorq %[fx], "=m" (*fx), [fx] "m" (*fx)); } static inline int copy_user_to_fxregs(struct fxregs_state __user *fx) { if (IS_ENABLED(CONFIG_X86_32)) return user_insn(fxrstor %[fx], "=m" (*fx), [fx] "m" (*fx)); - else if (IS_ENABLED(CONFIG_AS_FXSAVEQ)) + else return user_insn(fxrstorq %[fx], "=m" (*fx), [fx] "m" (*fx)); - - /* See comment in copy_fxregs_to_kernel() below. */ - return user_insn(rex64/fxrstor (%[fx]), "=m" (*fx), [fx] "R" (fx), - "m" (*fx)); } static inline void copy_kernel_to_fregs(struct fregs_state *fx) @@ -184,34 +172,8 @@ static inline void copy_fxregs_to_kernel(struct fpu *fpu) { if (IS_ENABLED(CONFIG_X86_32)) asm volatile( "fxsave %[fx]" : [fx] "=m" (fpu->state.fxsave)); - else if (IS_ENABLED(CONFIG_AS_FXSAVEQ)) + else asm volatile("fxsaveq %[fx]" : [fx] "=m" (fpu->state.fxsave)); - else { - /* Using "rex64; fxsave %0" is broken because, if the memory - * operand 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. - * - * Using "fxsaveq %0" would be the ideal choice, but is only - * supported starting with gas 2.16. - * - * Using, as a workaround, the properly prefixed form below - * isn't accepted by any binutils version so far released, - * complaining that the same type of prefix is used twice if - * an extended register is needed for addressing (fix submitted - * to mainline 2005-11-21). - * - * asm volatile("rex64/fxsave %0" : "=m" (fpu->state.fxsave)); - * - * This, however, we can work around by forcing the compiler to - * select an addressing mode that doesn't require extended - * registers. - */ - asm volatile( "rex64/fxsave (%[fx])" - : "=m" (fpu->state.fxsave) - : [fx] "R" (&fpu->state.fxsave)); - } } /* These macros all use (%edi)/(%rdi) as the single memory argument. */ diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c index 9b7c4ca8f0a7..2684a9d11e66 100644 --- a/arch/x86/kernel/traps.c +++ b/arch/x86/kernel/traps.c @@ -880,12 +880,12 @@ do_spurious_interrupt_bug(struct pt_regs *regs, long error_code) dotraplinkage void do_device_not_available(struct pt_regs *regs, long error_code) { - unsigned long cr0; + unsigned long cr0 = read_cr0(); RCU_LOCKDEP_WARN(!rcu_is_watching(), "entry code didn't wake RCU"); #ifdef CONFIG_MATH_EMULATION - if (!boot_cpu_has(X86_FEATURE_FPU) && (read_cr0() & X86_CR0_EM)) { + if (!boot_cpu_has(X86_FEATURE_FPU) && (cr0 & X86_CR0_EM)) { struct math_emu_info info = { }; cond_local_irq_enable(regs); @@ -897,7 +897,6 @@ do_device_not_available(struct pt_regs *regs, long error_code) #endif /* This should not happen. */ - cr0 = read_cr0(); if (WARN(cr0 & X86_CR0_TS, "CR0.TS was set")) { /* Try to fix it up and carry on. */ write_cr0(cr0 & ~X86_CR0_TS); |