From e6f8a6c86ce7b2108c03c1cc014fdae278573df1 Mon Sep 17 00:00:00 2001

From: Nicholas Piggin <npiggin@gmail.com>

Date: Sat, 30 Jan 2021 23:08:39 +1000

Subject: [PATCH] powerpc: add interrupt_cond_local_irq_enable helper

References: bsc#1065729

Patch-mainline: v5.12-rc1

Git-commit: e6f8a6c86ce7b2108c03c1cc014fdae278573df1

Simple helper for synchronous interrupt handlers (i.e., process-context)

to enable interrupts if it was taken in an interrupts-enabled context.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Link: https://lore.kernel.org/r/20210130130852.2952424-30-npiggin@gmail.com

Acked-by: Michal Suchanek <msuchanek@suse.de>

---

 arch/powerpc/include/asm/interrupt.h |  7 +++++++

 arch/powerpc/kernel/traps.c          | 24 +++++++-----------------

 arch/powerpc/mm/fault.c              |  4 +---

 3 files changed, 15 insertions(+), 20 deletions(-)

diff --git a/arch/powerpc/include/asm/irq.h b/arch/powerpc/include/asm/irq.h

--- a/arch/powerpc/include/asm/irq.h

+++ b/arch/powerpc/include/asm/irq.h

@@ -63,5 +63,11 @@ extern void __do_irq(struct pt_regs *regs);

 int irq_choose_cpu(const struct cpumask *mask);

+static inline void interrupt_cond_local_irq_enable(struct pt_regs *regs)

+{

+	if (!arch_irq_disabled_regs(regs))

+		local_irq_enable();

+}

+

 #endif /* _ASM_IRQ_H */

 #endif /* __KERNEL__ */

diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c

index 51e56b7fceb7..20c90a3548f6 100644

--- a/arch/powerpc/kernel/traps.c

+++ b/arch/powerpc/kernel/traps.c

@@ -343,8 +343,8 @@ static bool exception_common(int signr, struct pt_regs *regs, int code,

 	show_signal_msg(signr, regs, code, addr);

-	if (arch_irqs_disabled() && !arch_irq_disabled_regs(regs))

-		local_irq_enable();

+	if (arch_irqs_disabled())

+		interrupt_cond_local_irq_enable(regs);

 	current->thread.trap_nr = code;

@@ -1555,9 +1555,7 @@ static void do_program_check(struct pt_regs *regs)

 	if (!user_mode(regs))

 		goto sigill;

-	/* We restore the interrupt state now */

-	if (!arch_irq_disabled_regs(regs))

-		local_irq_enable();

+	interrupt_cond_local_irq_enable(regs);

 	/* (reason & REASON_ILLEGAL) would be the obvious thing here,

 	 * but there seems to be a hardware bug on the 405GP (RevD)

@@ -1622,9 +1620,7 @@ DEFINE_INTERRUPT_HANDLER(alignment_exception)

 	int sig, code, fixed = 0;

 	unsigned long  reason;

-	/* We restore the interrupt state now */

-	if (!arch_irq_disabled_regs(regs))

-		local_irq_enable();

+	interrupt_cond_local_irq_enable(regs);

 	reason = get_reason(regs);

@@ -1785,9 +1781,7 @@ DEFINE_INTERRUPT_HANDLER(facility_unavailable_exception)

 		die("Unexpected facility unavailable exception", regs, SIGABRT);

 	}

-	/* We restore the interrupt state now */

-	if (!arch_irq_disabled_regs(regs))

-		local_irq_enable();

+	interrupt_cond_local_irq_enable(regs);

 	if (status == FSCR_DSCR_LG) {

 		/*

@@ -2172,9 +2166,7 @@ DEFINE_INTERRUPT_HANDLER(SPEFloatingPointException)

 	int code = FPE_FLTUNK;

 	int err;

-	/* We restore the interrupt state now */

-	if (!arch_irq_disabled_regs(regs))

-		local_irq_enable();

+	interrupt_cond_local_irq_enable(regs);

 	flush_spe_to_thread(current);

@@ -2221,9 +2213,7 @@ DEFINE_INTERRUPT_HANDLER(SPEFloatingPointRoundException)

 	extern int speround_handler(struct pt_regs *regs);

 	int err;

-	/* We restore the interrupt state now */

-	if (!arch_irq_disabled_regs(regs))

-		local_irq_enable();

+	interrupt_cond_local_irq_enable(regs);

 	preempt_disable();

 	if (regs->msr & MSR_SPE)

diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c

index f8eb42aaafab..8552ab6c008b 100644

--- a/arch/powerpc/mm/fault.c

+++ b/arch/powerpc/mm/fault.c

@@ -434,9 +434,7 @@ static int __do_page_fault(struct pt_regs *regs, unsigned long address,

 		return bad_area_nosemaphore(regs, address);

 	}

-	/* We restore the interrupt state now */

-	if (!arch_irq_disabled_regs(regs))

-		local_irq_enable();

+	interrupt_cond_local_irq_enable(regs);

 	perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address);

-- 

2.31.1