From a546498f3bf9aac311c66f965186373aee2ca0b0 Mon Sep 17 00:00:00 2001 From: Benjamin Herrenschmidt Date: Wed, 7 Mar 2012 16:48:45 +1100 Subject: powerpc: Call do_page_fault() with interrupts off We currently turn interrupts back to their previous state before calling do_page_fault(). This can be annoying when debugging as a bad fault will potentially have lost some processor state before getting into the debugger. We also end up calling some generic code with interrupts enabled such as notify_page_fault() with interrupts enabled, which could be unexpected. This changes our code to behave more like other architectures, and make the assembly entry code call into do_page_faults() with interrupts disabled. They are conditionally re-enabled from within do_page_fault() in the same spot x86 does it. While there, add the might_sleep() test in the case of a successful trylock of the mmap semaphore, again like x86. Also fix a bug in the existing assembly where r12 (_MSR) could get clobbered by C calls (the DTL accounting in the exception common macro and DISABLE_INTS) in some cases. Signed-off-by: Benjamin Herrenschmidt --- v2. Add the r12 clobber fix --- arch/powerpc/include/asm/hw_irq.h | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'arch/powerpc/include') diff --git a/arch/powerpc/include/asm/hw_irq.h b/arch/powerpc/include/asm/hw_irq.h index bb712c9488b..531ba00fcba 100644 --- a/arch/powerpc/include/asm/hw_irq.h +++ b/arch/powerpc/include/asm/hw_irq.h @@ -79,6 +79,11 @@ static inline bool arch_irqs_disabled(void) get_paca()->hard_enabled = 0; \ } while(0) +static inline bool arch_irq_disabled_regs(struct pt_regs *regs) +{ + return !regs->softe; +} + #else /* CONFIG_PPC64 */ #define SET_MSR_EE(x) mtmsr(x) @@ -139,6 +144,11 @@ static inline bool arch_irqs_disabled(void) #define hard_irq_disable() arch_local_irq_disable() +static inline bool arch_irq_disabled_regs(struct pt_regs *regs) +{ + return !(regs->msr & MSR_EE); +} + #endif /* CONFIG_PPC64 */ #define ARCH_IRQ_INIT_FLAGS IRQ_NOREQUEST -- cgit v1.2.3