diff options
Diffstat (limited to 'arch/x86/include/asm/entry-common.h')
| -rw-r--r-- | arch/x86/include/asm/entry-common.h | 12 |
1 files changed, 10 insertions, 2 deletions
diff --git a/arch/x86/include/asm/entry-common.h b/arch/x86/include/asm/entry-common.h index 77d20555e04d..ce3eb6d5fdf9 100644 --- a/arch/x86/include/asm/entry-common.h +++ b/arch/x86/include/asm/entry-common.h @@ -53,7 +53,6 @@ static inline void arch_exit_work(unsigned long ti_work) if (unlikely(ti_work & _TIF_IO_BITMAP)) tss_update_io_bitmap(); - fpregs_assert_state_consistent(); if (unlikely(ti_work & _TIF_NEED_FPU_LOAD)) switch_fpu_return(); } @@ -61,7 +60,9 @@ static inline void arch_exit_work(unsigned long ti_work) static inline void arch_exit_to_user_mode_prepare(struct pt_regs *regs, unsigned long ti_work) { - if (IS_ENABLED(CONFIG_X86_DEBUG_FPU) || unlikely(ti_work)) + fpregs_assert_state_consistent(); + + if (unlikely(ti_work)) arch_exit_work(ti_work); fred_update_rsp0(); @@ -92,6 +93,13 @@ static inline void arch_exit_to_user_mode_prepare(struct pt_regs *regs, * 8 (ia32) bits. */ choose_random_kstack_offset(rdtsc()); + + /* Avoid unnecessary reads of 'x86_ibpb_exit_to_user' */ + if (cpu_feature_enabled(X86_FEATURE_IBPB_EXIT_TO_USER) && + this_cpu_read(x86_ibpb_exit_to_user)) { + indirect_branch_prediction_barrier(); + this_cpu_write(x86_ibpb_exit_to_user, false); + } } #define arch_exit_to_user_mode_prepare arch_exit_to_user_mode_prepare |