The following commit has been merged into the x86/entry branch of tip: Commit-ID: 800c8a1afb8e9d71ffb1ff54d6a2cf5c45dc50b5 Gitweb: https://git.kernel.org/tip/800c8a1afb8e9d71ffb1ff54d6a2cf5c45dc50b5 Author: Thomas Gleixner <[email protected]> AuthorDate: Wed, 04 Mar 2020 23:32:15 +01:00 Committer: Thomas Gleixner <[email protected]> CommitterDate: Tue, 19 May 2020 16:03:53 +02:00
x86/entry: Disable interrupts for native_load_gs_index() in C code There is absolutely no point in doing this in ASM code. Move it to C. Signed-off-by: Thomas Gleixner <[email protected]> Reviewed-by: Alexandre Chartre <[email protected]> Acked-by: Peter Zijlstra <[email protected]> Acked-by: Andy Lutomirski <[email protected]> Link: https://lkml.kernel.org/r/[email protected] --- arch/x86/entry/entry_64.S | 11 +++-------- arch/x86/include/asm/special_insns.h | 14 ++++++++++++-- 2 files changed, 15 insertions(+), 10 deletions(-) diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S index 9866b54..be8ed3a 100644 --- a/arch/x86/entry/entry_64.S +++ b/arch/x86/entry/entry_64.S @@ -1041,22 +1041,17 @@ idtentry simd_coprocessor_error do_simd_coprocessor_error has_error_code=0 * * Is in entry.text as it shouldn't be instrumented. */ -SYM_FUNC_START(native_load_gs_index) +SYM_FUNC_START(asm_load_gs_index) FRAME_BEGIN - pushfq - DISABLE_INTERRUPTS(CLBR_ANY & ~CLBR_RDI) - TRACE_IRQS_OFF SWAPGS .Lgs_change: movl %edi, %gs 2: ALTERNATIVE "", "mfence", X86_BUG_SWAPGS_FENCE SWAPGS - TRACE_IRQS_FLAGS (%rsp) - popfq FRAME_END ret -SYM_FUNC_END(native_load_gs_index) -EXPORT_SYMBOL(native_load_gs_index) +SYM_FUNC_END(asm_load_gs_index) +EXPORT_SYMBOL(asm_load_gs_index) _ASM_EXTABLE(.Lgs_change, .Lbad_gs) .section .fixup, "ax" diff --git a/arch/x86/include/asm/special_insns.h b/arch/x86/include/asm/special_insns.h index 6d37b8f..82436cb 100644 --- a/arch/x86/include/asm/special_insns.h +++ b/arch/x86/include/asm/special_insns.h @@ -7,6 +7,7 @@ #include <asm/nops.h> #include <asm/processor-flags.h> +#include <linux/irqflags.h> #include <linux/jump_label.h> /* @@ -129,7 +130,16 @@ static inline void native_wbinvd(void) asm volatile("wbinvd": : :"memory"); } -extern asmlinkage void native_load_gs_index(unsigned); +extern asmlinkage void asm_load_gs_index(unsigned int selector); + +static inline void native_load_gs_index(unsigned int selector) +{ + unsigned long flags; + + local_irq_save(flags); + asm_load_gs_index(selector); + local_irq_restore(flags); +} static inline unsigned long __read_cr4(void) { @@ -186,7 +196,7 @@ static inline void wbinvd(void) #ifdef CONFIG_X86_64 -static inline void load_gs_index(unsigned selector) +static inline void load_gs_index(unsigned int selector) { native_load_gs_index(selector); }
