diff options
| -rw-r--r-- | arch/x86/entry/common.c | 34 | ||||
| -rw-r--r-- | arch/x86/include/asm/idtentry.h | 3 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/mce/core.c | 6 | ||||
| -rw-r--r-- | arch/x86/kernel/nmi.c | 6 | ||||
| -rw-r--r-- | arch/x86/kernel/traps.c | 13 | ||||
| -rw-r--r-- | include/linux/entry-common.h | 39 | ||||
| -rw-r--r-- | kernel/entry/common.c | 36 |
7 files changed, 87 insertions, 50 deletions
diff --git a/arch/x86/entry/common.c b/arch/x86/entry/common.c index 870efeec8bda..18d8f17f755c 100644 --- a/arch/x86/entry/common.c +++ b/arch/x86/entry/common.c @@ -209,40 +209,6 @@ SYSCALL_DEFINE0(ni_syscall) return -ENOSYS; } -noinstr bool idtentry_enter_nmi(struct pt_regs *regs) -{ - bool irq_state = lockdep_hardirqs_enabled(); - - __nmi_enter(); - lockdep_hardirqs_off(CALLER_ADDR0); - lockdep_hardirq_enter(); - rcu_nmi_enter(); - - instrumentation_begin(); - trace_hardirqs_off_finish(); - ftrace_nmi_enter(); - instrumentation_end(); - - return irq_state; -} - -noinstr void idtentry_exit_nmi(struct pt_regs *regs, bool restore) -{ - instrumentation_begin(); - ftrace_nmi_exit(); - if (restore) { - trace_hardirqs_on_prepare(); - lockdep_hardirqs_on_prepare(CALLER_ADDR0); - } - instrumentation_end(); - - rcu_nmi_exit(); - lockdep_hardirq_exit(); - if (restore) - lockdep_hardirqs_on(CALLER_ADDR0); - __nmi_exit(); -} - #ifdef CONFIG_XEN_PV #ifndef CONFIG_PREEMPTION /* diff --git a/arch/x86/include/asm/idtentry.h b/arch/x86/include/asm/idtentry.h index b2442eb0ac2f..247a60a47331 100644 --- a/arch/x86/include/asm/idtentry.h +++ b/arch/x86/include/asm/idtentry.h @@ -11,9 +11,6 @@ #include <asm/irq_stack.h> -bool idtentry_enter_nmi(struct pt_regs *regs); -void idtentry_exit_nmi(struct pt_regs *regs, bool irq_state); - /** * DECLARE_IDTENTRY - Declare functions for simple IDT entry points * No error code pushed by hardware diff --git a/arch/x86/kernel/cpu/mce/core.c b/arch/x86/kernel/cpu/mce/core.c index 4102b866e7c0..f5c860b1a50b 100644 --- a/arch/x86/kernel/cpu/mce/core.c +++ b/arch/x86/kernel/cpu/mce/core.c @@ -1983,7 +1983,7 @@ void (*machine_check_vector)(struct pt_regs *) = unexpected_machine_check; static __always_inline void exc_machine_check_kernel(struct pt_regs *regs) { - bool irq_state; + irqentry_state_t irq_state; WARN_ON_ONCE(user_mode(regs)); @@ -1995,7 +1995,7 @@ static __always_inline void exc_machine_check_kernel(struct pt_regs *regs) mce_check_crashing_cpu()) return; - irq_state = idtentry_enter_nmi(regs); + irq_state = irqentry_nmi_enter(regs); /* * The call targets are marked noinstr, but objtool can't figure * that out because it's an indirect call. Annotate it. @@ -2006,7 +2006,7 @@ static __always_inline void exc_machine_check_kernel(struct pt_regs *regs) if (regs->flags & X86_EFLAGS_IF) trace_hardirqs_on_prepare(); instrumentation_end(); - idtentry_exit_nmi(regs, irq_state); + irqentry_nmi_exit(regs, irq_state); } static __always_inline void exc_machine_check_user(struct pt_regs *regs) diff --git a/arch/x86/kernel/nmi.c b/arch/x86/kernel/nmi.c index 4bc77aaf1303..bf250a339655 100644 --- a/arch/x86/kernel/nmi.c +++ b/arch/x86/kernel/nmi.c @@ -475,7 +475,7 @@ static DEFINE_PER_CPU(unsigned long, nmi_dr7); DEFINE_IDTENTRY_RAW(exc_nmi) { - bool irq_state; + irqentry_state_t irq_state; /* * Re-enable NMIs right here when running as an SEV-ES guest. This might @@ -502,14 +502,14 @@ nmi_restart: this_cpu_write(nmi_dr7, local_db_save()); - irq_state = idtentry_enter_nmi(regs); + irq_state = irqentry_nmi_enter(regs); inc_irq_stat(__nmi_count); if (!ignore_nmis) default_do_nmi(regs); - idtentry_exit_nmi(regs, irq_state); + irqentry_nmi_exit(regs, irq_state); local_db_restore(this_cpu_read(nmi_dr7)); diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c index e19df6cde35d..e1b78829d909 100644 --- a/arch/x86/kernel/traps.c +++ b/arch/x86/kernel/traps.c @@ -405,7 +405,7 @@ DEFINE_IDTENTRY_DF(exc_double_fault) } #endif - idtentry_enter_nmi(regs); + irqentry_nmi_enter(regs); instrumentation_begin(); notify_die(DIE_TRAP, str, regs, error_code, X86_TRAP_DF, SIGSEGV); @@ -651,12 +651,13 @@ DEFINE_IDTENTRY_RAW(exc_int3) instrumentation_end(); irqentry_exit_to_user_mode(regs); } else { - bool irq_state = idtentry_enter_nmi(regs); + irqentry_state_t irq_state = irqentry_nmi_enter(regs); + instrumentation_begin(); if (!do_int3(regs)) die("int3", regs, 0); instrumentation_end(); - idtentry_exit_nmi(regs, irq_state); + irqentry_nmi_exit(regs, irq_state); } } @@ -851,7 +852,7 @@ static __always_inline void exc_debug_kernel(struct pt_regs *regs, * includes the entry stack is excluded for everything. */ unsigned long dr7 = local_db_save(); - bool irq_state = idtentry_enter_nmi(regs); + irqentry_state_t irq_state = irqentry_nmi_enter(regs); instrumentation_begin(); /* @@ -908,7 +909,7 @@ static __always_inline void exc_debug_kernel(struct pt_regs *regs, regs->flags &= ~X86_EFLAGS_TF; out: instrumentation_end(); - idtentry_exit_nmi(regs, irq_state); + irqentry_nmi_exit(regs, irq_state); local_db_restore(dr7); } @@ -926,7 +927,7 @@ static __always_inline void exc_debug_user(struct pt_regs *regs, /* * NB: We can't easily clear DR7 here because - * idtentry_exit_to_usermode() can invoke ptrace, schedule, access + * irqentry_exit_to_usermode() can invoke ptrace, schedule, access * user memory, etc. This means that a recursive #DB is possible. If * this happens, that #DB will hit exc_debug_kernel() and clear DR7. * Since we're not on the IST stack right now, everything will be diff --git a/include/linux/entry-common.h b/include/linux/entry-common.h index b9711e813ec2..1a128baf3628 100644 --- a/include/linux/entry-common.h +++ b/include/linux/entry-common.h @@ -346,8 +346,26 @@ void irqentry_enter_from_user_mode(struct pt_regs *regs); void irqentry_exit_to_user_mode(struct pt_regs *regs); #ifndef irqentry_state +/** + * struct irqentry_state - Opaque object for exception state storage + * @exit_rcu: Used exclusively in the irqentry_*() calls; signals whether the + * exit path has to invoke rcu_irq_exit(). + * @lockdep: Used exclusively in the irqentry_nmi_*() calls; ensures that + * lockdep state is restored correctly on exit from nmi. + * + * This opaque object is filled in by the irqentry_*_enter() functions and + * must be passed back into the corresponding irqentry_*_exit() functions + * when the exception is complete. + * + * Callers of irqentry_*_[enter|exit]() must consider this structure opaque + * and all members private. Descriptions of the members are provided to aid in + * the maintenance of the irqentry_*() functions. + */ typedef struct irqentry_state { - bool exit_rcu; + union { + bool exit_rcu; + bool lockdep; + }; } irqentry_state_t; #endif @@ -407,4 +425,23 @@ void irqentry_exit_cond_resched(void); */ void noinstr irqentry_exit(struct pt_regs *regs, irqentry_state_t state); +/** + * irqentry_nmi_enter - Handle NMI entry + * @regs: Pointer to currents pt_regs + * + * Similar to irqentry_enter() but taking care of the NMI constraints. + */ +irqentry_state_t noinstr irqentry_nmi_enter(struct pt_regs *regs); + +/** + * irqentry_nmi_exit - Handle return from NMI handling + * @regs: Pointer to pt_regs (NMI entry regs) + * @irq_state: Return value from matching call to irqentry_nmi_enter() + * + * Last action before returning to the low level assmenbly code. + * + * Counterpart to irqentry_nmi_enter(). + */ +void noinstr irqentry_nmi_exit(struct pt_regs *regs, irqentry_state_t irq_state); + #endif diff --git a/kernel/entry/common.c b/kernel/entry/common.c index 3a1dfecc533e..bc75c114c1b3 100644 --- a/kernel/entry/common.c +++ b/kernel/entry/common.c @@ -405,3 +405,39 @@ noinstr void irqentry_exit(struct pt_regs *regs, irqentry_state_t state) rcu_irq_exit(); } } + +irqentry_state_t noinstr irqentry_nmi_enter(struct pt_regs *regs) +{ + irqentry_state_t irq_state; + + irq_state.lockdep = lockdep_hardirqs_enabled(); + + __nmi_enter(); + lockdep_hardirqs_off(CALLER_ADDR0); + lockdep_hardirq_enter(); + rcu_nmi_enter(); + + instrumentation_begin(); + trace_hardirqs_off_finish(); + ftrace_nmi_enter(); + instrumentation_end(); + + return irq_state; +} + +void noinstr irqentry_nmi_exit(struct pt_regs *regs, irqentry_state_t irq_state) +{ + instrumentation_begin(); + ftrace_nmi_exit(); + if (irq_state.lockdep) { + trace_hardirqs_on_prepare(); + lockdep_hardirqs_on_prepare(CALLER_ADDR0); + } + instrumentation_end(); + + rcu_nmi_exit(); + lockdep_hardirq_exit(); + if (irq_state.lockdep) + lockdep_hardirqs_on(CALLER_ADDR0); + __nmi_exit(); +} |