From: Oleg Nesterov Date: Sat, 3 May 2025 14:39:02 +0000 (+0200) Subject: x86/fpu: Shift fpregs_assert_state_consistent() from arch_exit_work() to its caller X-Git-Tag: v6.16-rc1~195^2~28^2~3 X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=46c158e3ad0fc633007802c338c409c188ec0a12;p=linux.git x86/fpu: Shift fpregs_assert_state_consistent() from arch_exit_work() to its caller If CONFIG_X86_DEBUG_FPU=Y, arch_exit_to_user_mode_prepare() calls arch_exit_work() even if ti_work == 0. There only reason is that we want to call fpregs_assert_state_consistent() if TIF_NEED_FPU_LOAD is not set. This looks confusing. arch_exit_to_user_mode_prepare() can just call fpregs_assert_state_consistent() unconditionally, it depends on CONFIG_X86_DEBUG_FPU and checks TIF_NEED_FPU_LOAD itself. Signed-off-by: Oleg Nesterov Signed-off-by: Ingo Molnar Cc: Chang S . Bae Cc: H. Peter Anvin Cc: Andy Lutomirski Cc: Brian Gerst Cc: Linus Torvalds Cc: Peter Zijlstra Link: https://lore.kernel.org/r/20250503143902.GA9012@redhat.com --- diff --git a/arch/x86/include/asm/entry-common.h b/arch/x86/include/asm/entry-common.h index 77d20555e04d..d535a97c7284 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();