From b98cca444d287a63dd96df04af7fb9793567599e Mon Sep 17 00:00:00 2001 From: Anshuman Khandual Date: Tue, 16 Jul 2019 16:28:00 -0700 Subject: mm, kprobes: generalize and rename notify_page_fault() as kprobe_page_fault() Architectures which support kprobes have very similar boilerplate around calling kprobe_fault_handler(). Use a helper function in kprobes.h to unify them, based on the x86 code. This changes the behaviour for other architectures when preemption is enabled. Previously, they would have disabled preemption while calling the kprobe handler. However, preemption would be disabled if this fault was due to a kprobe, so we know the fault was not due to a kprobe handler and can simply return failure. This behaviour was introduced in commit a980c0ef9f6d ("x86/kprobes: Refactor kprobes_fault() like kprobe_exceptions_notify()") [anshuman.khandual@arm.com: export kprobe_fault_handler()] Link: http://lkml.kernel.org/r/1561133358-8876-1-git-send-email-anshuman.khandual@arm.com Link: http://lkml.kernel.org/r/1560420444-25737-1-git-send-email-anshuman.khandual@arm.com Signed-off-by: Anshuman Khandual Reviewed-by: Dave Hansen Cc: Michal Hocko Cc: Matthew Wilcox Cc: Mark Rutland Cc: Christophe Leroy Cc: Stephen Rothwell Cc: Andrey Konovalov Cc: Michael Ellerman Cc: Paul Mackerras Cc: Russell King Cc: Catalin Marinas Cc: Will Deacon Cc: Tony Luck Cc: Fenghua Yu Cc: Martin Schwidefsky Cc: Heiko Carstens Cc: Yoshinori Sato Cc: "David S. Miller" Cc: Thomas Gleixner Cc: Peter Zijlstra Cc: Ingo Molnar Cc: Andy Lutomirski Cc: Vineet Gupta Cc: James Hogan Cc: Paul Burton Cc: Ralf Baechle Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/sh/mm/fault.c | 18 ++---------------- 1 file changed, 2 insertions(+), 16 deletions(-) (limited to 'arch/sh') diff --git a/arch/sh/mm/fault.c b/arch/sh/mm/fault.c index 3093bc372138..5f51456f4fc7 100644 --- a/arch/sh/mm/fault.c +++ b/arch/sh/mm/fault.c @@ -24,20 +24,6 @@ #include #include -static inline int notify_page_fault(struct pt_regs *regs, int trap) -{ - int ret = 0; - - if (kprobes_built_in() && !user_mode(regs)) { - preempt_disable(); - if (kprobe_running() && kprobe_fault_handler(regs, trap)) - ret = 1; - preempt_enable(); - } - - return ret; -} - static void force_sig_info_fault(int si_signo, int si_code, unsigned long address) { @@ -412,14 +398,14 @@ asmlinkage void __kprobes do_page_fault(struct pt_regs *regs, if (unlikely(fault_in_kernel_space(address))) { if (vmalloc_fault(address) >= 0) return; - if (notify_page_fault(regs, vec)) + if (kprobe_page_fault(regs, vec)) return; bad_area_nosemaphore(regs, error_code, address); return; } - if (unlikely(notify_page_fault(regs, vec))) + if (unlikely(kprobe_page_fault(regs, vec))) return; /* Only enable interrupts if they were on before the fault */ -- cgit v1.2.3