diff --git a/arch/x86/include/asm/traps.h b/arch/x86/include/asm/traps.h index b44d74009ec3d9a6c81c41baf3108984d3b29598..12700ab2b59b0a84feec72d67966f2f9f2f54461 100644 --- a/arch/x86/include/asm/traps.h +++ b/arch/x86/include/asm/traps.h @@ -109,9 +109,6 @@ asmlinkage void smp_threshold_interrupt(struct pt_regs *regs); asmlinkage void smp_deferred_error_interrupt(struct pt_regs *regs); #endif -extern void ist_enter(struct pt_regs *regs); -extern void ist_exit(struct pt_regs *regs); - #ifdef CONFIG_VMAP_STACK void __noreturn handle_stack_overflow(const char *message, struct pt_regs *regs, diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c index fecac9fcd92d46092dba1b16b6873f0dc72ffef3..ec5d86910d474b611ae5927564b42c56e6f15dcf 100644 --- a/arch/x86/kernel/cpu/mcheck/mce.c +++ b/arch/x86/kernel/cpu/mcheck/mce.c @@ -44,6 +44,7 @@ #include #include #include +#include #include #include @@ -1266,7 +1267,7 @@ void do_machine_check(struct pt_regs *regs, long error_code) if (__mc_check_crashing_cpu(cpu)) return; - ist_enter(regs); + nmi_enter(); this_cpu_inc(mce_exception_count); @@ -1372,7 +1373,7 @@ void do_machine_check(struct pt_regs *regs, long error_code) } out_ist: - ist_exit(regs); + nmi_exit(); } EXPORT_SYMBOL_GPL(do_machine_check); diff --git a/arch/x86/kernel/cpu/mcheck/p5.c b/arch/x86/kernel/cpu/mcheck/p5.c index 5cddf831720fd321b01a7393b8c678d635b46e4b..92ee53cb1de09f51d2391987bac4de12e00d41e8 100644 --- a/arch/x86/kernel/cpu/mcheck/p5.c +++ b/arch/x86/kernel/cpu/mcheck/p5.c @@ -7,6 +7,7 @@ #include #include #include +#include #include #include @@ -22,7 +23,7 @@ static void pentium_machine_check(struct pt_regs *regs, long error_code) { u32 loaddr, hi, lotype; - ist_enter(regs); + nmi_enter(); rdmsr(MSR_IA32_P5_MC_ADDR, loaddr, hi); rdmsr(MSR_IA32_P5_MC_TYPE, lotype, hi); @@ -37,7 +38,7 @@ static void pentium_machine_check(struct pt_regs *regs, long error_code) add_taint(TAINT_MACHINE_CHECK, LOCKDEP_NOW_UNRELIABLE); - ist_exit(regs); + nmi_exit(); } /* Set up machine check reporting for processors with Intel style MCE: */ diff --git a/arch/x86/kernel/cpu/mcheck/winchip.c b/arch/x86/kernel/cpu/mcheck/winchip.c index 3b45b270a865d1658648667451f4b57fede21f26..3677b197c4683f95523be95db389c5f5b0b4c6af 100644 --- a/arch/x86/kernel/cpu/mcheck/winchip.c +++ b/arch/x86/kernel/cpu/mcheck/winchip.c @@ -6,6 +6,7 @@ #include #include #include +#include #include #include @@ -16,12 +17,12 @@ /* Machine check handler for WinChip C6: */ static void winchip_machine_check(struct pt_regs *regs, long error_code) { - ist_enter(regs); + nmi_enter(); pr_emerg("CPU0: Machine Check Exception.\n"); add_taint(TAINT_MACHINE_CHECK, LOCKDEP_NOW_UNRELIABLE); - ist_exit(regs); + nmi_exit(); } /* Set up machine check reporting on the Winchip C6 series */ diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c index b757098e458551b29dab82f0187ad8aaa244ee10..df711a9f3311f8c800c798c4375eec63983be6b5 100644 --- a/arch/x86/kernel/traps.c +++ b/arch/x86/kernel/traps.c @@ -37,6 +37,8 @@ #include #include #include +#include +#include #if defined(CONFIG_EDAC) #include @@ -45,7 +47,6 @@ #include #include #include -#include #include #include #include @@ -86,40 +87,6 @@ static inline void cond_local_irq_disable(struct pt_regs *regs) local_irq_disable(); } -/* - * In IST context, we explicitly disable preemption. This serves two - * purposes: it makes it much less likely that we would accidentally - * schedule in IST context and it will force a warning if we somehow - * manage to schedule by accident. - */ -void ist_enter(struct pt_regs *regs) -{ - if (user_mode(regs)) { - RCU_LOCKDEP_WARN(!rcu_is_watching(), "entry code didn't wake RCU"); - } else { - /* - * We might have interrupted pretty much anything. In - * fact, if we're a machine check, we can even interrupt - * NMI processing. We don't want in_nmi() to return true, - * but we need to notify RCU. - */ - rcu_nmi_enter(); - } - - preempt_disable(); - - /* This code is a bit fragile. Test it. */ - RCU_LOCKDEP_WARN(!rcu_is_watching(), "ist_enter didn't work"); -} - -void ist_exit(struct pt_regs *regs) -{ - preempt_enable_no_resched(); - - if (!user_mode(regs)) - rcu_nmi_exit(); -} - int is_valid_bugaddr(unsigned long addr) { unsigned short ud; @@ -323,7 +290,7 @@ dotraplinkage void do_double_fault(struct pt_regs *regs, long error_code) * The net result is that our #GP handler will think that we * entered from usermode with the bad user context. * - * No need for ist_enter here because we don't use RCU. + * No need for nmi_enter() here because we don't use RCU. */ if (((long)regs->sp >> P4D_SHIFT) == ESPFIX_PGD_ENTRY && regs->cs == __KERNEL_CS && @@ -354,7 +321,7 @@ dotraplinkage void do_double_fault(struct pt_regs *regs, long error_code) } #endif - ist_enter(regs); + nmi_enter(); notify_die(DIE_TRAP, str, regs, error_code, X86_TRAP_DF, SIGSEGV); tsk->thread.error_code = error_code; @@ -555,15 +522,7 @@ dotraplinkage void notrace do_int3(struct pt_regs *regs, long error_code) if (poke_int3_handler(regs)) return; - /* - * Use ist_enter despite the fact that we don't use an IST stack. - * We can be called from a kprobe in non-CONTEXT_KERNEL kernel - * mode or even during context tracking state changes. - * - * This means that we can't schedule. That's okay. - */ - ist_enter(regs); - RCU_LOCKDEP_WARN(!rcu_is_watching(), "entry code didn't wake RCU"); + nmi_enter(); #ifdef CONFIG_KGDB_LOW_LEVEL_TRAP if (kgdb_ll_trap(DIE_INT3, "int3", regs, error_code, X86_TRAP_BP, SIGTRAP) == NOTIFY_STOP) @@ -584,7 +543,7 @@ dotraplinkage void notrace do_int3(struct pt_regs *regs, long error_code) cond_local_irq_disable(regs); exit: - ist_exit(regs); + nmi_exit(); } NOKPROBE_SYMBOL(do_int3); @@ -688,7 +647,7 @@ dotraplinkage void do_debug(struct pt_regs *regs, long error_code) unsigned long dr6; int si_code; - ist_enter(regs); + nmi_enter(); get_debugreg(dr6, 6); /* @@ -781,7 +740,7 @@ dotraplinkage void do_debug(struct pt_regs *regs, long error_code) debug_stack_usage_dec(); exit: - ist_exit(regs); + nmi_exit(); } NOKPROBE_SYMBOL(do_debug);