From fa95d7dc1abceb288db2959badb9aaf558eb0530 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Thu, 21 May 2020 22:05:19 +0200 Subject: [PATCH] x86/idtentry: Switch to conditional RCU handling Switch all idtentry_enter/exit() users over to the new conditional RCU handling scheme and make the user mode entries in #DB, #INT3 and #MCE use the user mode idtentry functions. Signed-off-by: Thomas Gleixner Signed-off-by: Ingo Molnar Acked-by: Andy Lutomirski Link: https://lore.kernel.org/r/20200521202117.382387286@linutronix.de --- arch/x86/include/asm/idtentry.h | 10 ++++++---- arch/x86/kernel/cpu/mce/core.c | 4 ++-- arch/x86/kernel/traps.c | 10 +++++----- 3 files changed, 13 insertions(+), 11 deletions(-) diff --git a/arch/x86/include/asm/idtentry.h b/arch/x86/include/asm/idtentry.h index b3aca728f2..0f974e5 100644 --- a/arch/x86/include/asm/idtentry.h +++ b/arch/x86/include/asm/idtentry.h @@ -61,11 +61,12 @@ static __always_inline void __##func(struct pt_regs *regs); \ \ __visible noinstr void func(struct pt_regs *regs) \ { \ - idtentry_enter(regs); \ + bool rcu_exit = idtentry_enter_cond_rcu(regs); \ + \ instrumentation_begin(); \ __##func (regs); \ instrumentation_end(); \ - idtentry_exit(regs); \ + idtentry_exit_cond_rcu(regs, rcu_exit); \ } \ \ static __always_inline void __##func(struct pt_regs *regs) @@ -107,11 +108,12 @@ static __always_inline void __##func(struct pt_regs *regs, \ __visible noinstr void func(struct pt_regs *regs, \ unsigned long error_code) \ { \ - idtentry_enter(regs); \ + bool rcu_exit = idtentry_enter_cond_rcu(regs); \ + \ instrumentation_begin(); \ __##func (regs, error_code); \ instrumentation_end(); \ - idtentry_exit(regs); \ + idtentry_exit_cond_rcu(regs, rcu_exit); \ } \ \ static __always_inline void __##func(struct pt_regs *regs, \ diff --git a/arch/x86/kernel/cpu/mce/core.c b/arch/x86/kernel/cpu/mce/core.c index a32a7e2..c47f004 100644 --- a/arch/x86/kernel/cpu/mce/core.c +++ b/arch/x86/kernel/cpu/mce/core.c @@ -1929,11 +1929,11 @@ static __always_inline void exc_machine_check_kernel(struct pt_regs *regs) static __always_inline void exc_machine_check_user(struct pt_regs *regs) { - idtentry_enter(regs); + idtentry_enter_user(regs); instrumentation_begin(); machine_check_vector(regs); instrumentation_end(); - idtentry_exit(regs); + idtentry_exit_user(regs); } #ifdef CONFIG_X86_64 diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c index 9e5d81c..f28be3e 100644 --- a/arch/x86/kernel/traps.c +++ b/arch/x86/kernel/traps.c @@ -619,18 +619,18 @@ DEFINE_IDTENTRY_RAW(exc_int3) return; /* - * idtentry_enter() uses static_branch_{,un}likely() and therefore + * idtentry_enter_user() uses static_branch_{,un}likely() and therefore * can trigger INT3, hence poke_int3_handler() must be done * before. If the entry came from kernel mode, then use nmi_enter() * because the INT3 could have been hit in any context including * NMI. */ if (user_mode(regs)) { - idtentry_enter(regs); + idtentry_enter_user(regs); instrumentation_begin(); do_int3_user(regs); instrumentation_end(); - idtentry_exit(regs); + idtentry_exit_user(regs); } else { nmi_enter(); instrumentation_begin(); @@ -877,7 +877,7 @@ static __always_inline void exc_debug_kernel(struct pt_regs *regs, static __always_inline void exc_debug_user(struct pt_regs *regs, unsigned long dr6) { - idtentry_enter(regs); + idtentry_enter_user(regs); clear_thread_flag(TIF_BLOCKSTEP); /* @@ -886,7 +886,7 @@ static __always_inline void exc_debug_user(struct pt_regs *regs, * User wants a sigtrap for that. */ handle_debug(regs, dr6, !dr6); - idtentry_exit(regs); + idtentry_exit_user(regs); } #ifdef CONFIG_X86_64 -- 2.7.4