From 010060741ad35eacb504414bc6fb9bb575b15f62 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Thu, 29 Jan 2009 16:02:12 +0100 Subject: x86: add might_sleep() to do_page_fault() Impact: widen debug checks VirtualBox calls do_page_fault() from an atomic context but runs into a might_sleep() way pas this point, cure that. Signed-off-by: Peter Zijlstra Signed-off-by: Ingo Molnar --- arch/x86/mm/fault.c | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'arch/x86/mm/fault.c') diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index 8f4b859..eb4d7fe 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -888,6 +888,12 @@ void __kprobes do_page_fault(struct pt_regs *regs, unsigned long error_code) return; } down_read(&mm->mmap_sem); + } else { + /* + * The above down_read_trylock() might have succeeded in which + * case we'll have missed the might_sleep() from down_read(). + */ + might_sleep(); } vma = find_vma(mm, address); -- cgit v1.1 From 0973a06cde8cc1522fbcf2baacb926f1ee3f4c79 Mon Sep 17 00:00:00 2001 From: Hiroshi Shimamoto Date: Wed, 4 Feb 2009 15:24:09 -0800 Subject: x86: mm: introduce helper function in fault.c Impact: cleanup Introduce helper function fault_in_kernel_address() to make editors happy. Signed-off-by: Hiroshi Shimamoto Signed-off-by: H. Peter Anvin --- arch/x86/mm/fault.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) (limited to 'arch/x86/mm/fault.c') diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index eb4d7fe..8e9b0f1 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -775,6 +775,15 @@ static inline int access_error(unsigned long error_code, int write, return 0; } +static int fault_in_kernel_space(unsigned long address) +{ +#ifdef CONFIG_X86_32 + return address >= TASK_SIZE; +#else /* !CONFIG_X86_32 */ + return address >= TASK_SIZE64; +#endif /* CONFIG_X86_32 */ +} + /* * This routine handles page faults. It determines the address, * and the problem, and then passes it off to one of the appropriate @@ -817,11 +826,7 @@ void __kprobes do_page_fault(struct pt_regs *regs, unsigned long error_code) * (error_code & 4) == 0, and that the fault was not a * protection error (error_code & 9) == 0. */ -#ifdef CONFIG_X86_32 - if (unlikely(address >= TASK_SIZE)) { -#else - if (unlikely(address >= TASK_SIZE64)) { -#endif + if (unlikely(fault_in_kernel_space(address))) { if (!(error_code & (PF_RSVD|PF_USER|PF_PROT)) && vmalloc_fault(address) >= 0) return; -- cgit v1.1