From 6ecbb582b6947f041832fff07c2f38791ae19287 Mon Sep 17 00:00:00 2001 From: Nicholas Piggin Date: Sat, 30 Jan 2021 23:08:50 +1000 Subject: [PATCH] powerpc/64s: move NMI soft-mask handling to C Saving and restoring soft-mask state can now be done in C using the interrupt handler wrapper functions. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20210130130852.2952424-41-npiggin@gmail.com --- arch/powerpc/include/asm/interrupt.h | 25 +++++++++++++++ arch/powerpc/kernel/exceptions-64s.S | 60 ------------------------------------ 2 files changed, 25 insertions(+), 60 deletions(-) diff --git a/arch/powerpc/include/asm/interrupt.h b/arch/powerpc/include/asm/interrupt.h index cd819d4..72a5850 100644 --- a/arch/powerpc/include/asm/interrupt.h +++ b/arch/powerpc/include/asm/interrupt.h @@ -95,6 +95,10 @@ static inline void interrupt_async_exit_prepare(struct pt_regs *regs, struct int struct interrupt_nmi_state { #ifdef CONFIG_PPC64 +#ifdef CONFIG_PPC_BOOK3S_64 + u8 irq_soft_mask; + u8 irq_happened; +#endif u8 ftrace_enabled; #endif }; @@ -102,6 +106,20 @@ struct interrupt_nmi_state { static inline void interrupt_nmi_enter_prepare(struct pt_regs *regs, struct interrupt_nmi_state *state) { #ifdef CONFIG_PPC64 +#ifdef CONFIG_PPC_BOOK3S_64 + state->irq_soft_mask = local_paca->irq_soft_mask; + state->irq_happened = local_paca->irq_happened; + + /* + * Set IRQS_ALL_DISABLED unconditionally so irqs_disabled() does + * the right thing, and set IRQ_HARD_DIS. We do not want to reconcile + * because that goes through irq tracing which we don't want in NMI. + */ + local_paca->irq_soft_mask = IRQS_ALL_DISABLED; + local_paca->irq_happened |= PACA_IRQ_HARD_DIS; + + /* Don't do any per-CPU operations until interrupt state is fixed */ +#endif /* Allow DEC and PMI to be traced when they are soft-NMI */ if (TRAP(regs) != 0x900 && TRAP(regs) != 0xf00 && TRAP(regs) != 0x260) { state->ftrace_enabled = this_cpu_get_ftrace_enabled(); @@ -129,6 +147,13 @@ static inline void interrupt_nmi_exit_prepare(struct pt_regs *regs, struct inter #ifdef CONFIG_PPC64 if (TRAP(regs) != 0x900 && TRAP(regs) != 0xf00 && TRAP(regs) != 0x260) this_cpu_set_ftrace_enabled(state->ftrace_enabled); + +#ifdef CONFIG_PPC_BOOK3S_64 + /* Check we didn't change the pending interrupt mask. */ + WARN_ON_ONCE((state->irq_happened | PACA_IRQ_HARD_DIS) != local_paca->irq_happened); + local_paca->irq_happened = state->irq_happened; + local_paca->irq_soft_mask = state->irq_soft_mask; +#endif #endif } diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S index 898698c..ec3e834 100644 --- a/arch/powerpc/kernel/exceptions-64s.S +++ b/arch/powerpc/kernel/exceptions-64s.S @@ -1008,20 +1008,6 @@ EXC_COMMON_BEGIN(system_reset_common) ld r1,PACA_NMI_EMERG_SP(r13) subi r1,r1,INT_FRAME_SIZE __GEN_COMMON_BODY system_reset - /* - * Set IRQS_ALL_DISABLED unconditionally so irqs_disabled() does - * the right thing. We do not want to reconcile because that goes - * through irq tracing which we don't want in NMI. - * - * Save PACAIRQHAPPENED to RESULT (otherwise unused), and set HARD_DIS - * as we are running with MSR[EE]=0. - */ - li r10,IRQS_ALL_DISABLED - stb r10,PACAIRQSOFTMASK(r13) - lbz r10,PACAIRQHAPPENED(r13) - std r10,RESULT(r1) - ori r10,r10,PACA_IRQ_HARD_DIS - stb r10,PACAIRQHAPPENED(r13) addi r3,r1,STACK_FRAME_OVERHEAD bl system_reset_exception @@ -1037,14 +1023,6 @@ EXC_COMMON_BEGIN(system_reset_common) subi r10,r10,1 sth r10,PACA_IN_NMI(r13) - /* - * Restore soft mask settings. - */ - ld r10,RESULT(r1) - stb r10,PACAIRQHAPPENED(r13) - ld r10,SOFTE(r1) - stb r10,PACAIRQSOFTMASK(r13) - kuap_kernel_restore r9, r10 EXCEPTION_RESTORE_REGS RFI_TO_USER_OR_KERNEL @@ -1190,30 +1168,11 @@ END_FTR_SECTION_IFSET(CPU_FTR_HVMODE) li r10,MSR_RI mtmsrd r10,1 - /* - * Set IRQS_ALL_DISABLED and save PACAIRQHAPPENED (see - * system_reset_common) - */ - li r10,IRQS_ALL_DISABLED - stb r10,PACAIRQSOFTMASK(r13) - lbz r10,PACAIRQHAPPENED(r13) - std r10,RESULT(r1) - ori r10,r10,PACA_IRQ_HARD_DIS - stb r10,PACAIRQHAPPENED(r13) - addi r3,r1,STACK_FRAME_OVERHEAD bl machine_check_early std r3,RESULT(r1) /* Save result */ ld r12,_MSR(r1) - /* - * Restore soft mask settings. - */ - ld r10,RESULT(r1) - stb r10,PACAIRQHAPPENED(r13) - ld r10,SOFTE(r1) - stb r10,PACAIRQSOFTMASK(r13) - #ifdef CONFIG_PPC_P7_NAP /* * Check if thread was in power saving mode. We come here when any @@ -2818,17 +2777,6 @@ EXC_COMMON_BEGIN(soft_nmi_common) subi r1,r1,INT_FRAME_SIZE __GEN_COMMON_BODY soft_nmi - /* - * Set IRQS_ALL_DISABLED and save PACAIRQHAPPENED (see - * system_reset_common) - */ - li r10,IRQS_ALL_DISABLED - stb r10,PACAIRQSOFTMASK(r13) - lbz r10,PACAIRQHAPPENED(r13) - std r10,RESULT(r1) - ori r10,r10,PACA_IRQ_HARD_DIS - stb r10,PACAIRQHAPPENED(r13) - addi r3,r1,STACK_FRAME_OVERHEAD bl soft_nmi_interrupt @@ -2836,14 +2784,6 @@ EXC_COMMON_BEGIN(soft_nmi_common) li r9,0 mtmsrd r9,1 - /* - * Restore soft mask settings. - */ - ld r10,RESULT(r1) - stb r10,PACAIRQHAPPENED(r13) - ld r10,SOFTE(r1) - stb r10,PACAIRQSOFTMASK(r13) - kuap_kernel_restore r9, r10 EXCEPTION_RESTORE_REGS hsrr=0 RFI_TO_KERNEL -- 2.7.4