From 7fb08eca45270d0ae86e1ad9d39c40b7a55d0190 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Mon, 15 Dec 2014 14:46:06 -0800 Subject: [PATCH] x86: mm: move mmap_sem unlock from mm_fault_error() to caller This replaces four copies in various stages of mm_fault_error() handling with just a single one. It will also allow for more natural placement of the unlocking after some further cleanup. Signed-off-by: Linus Torvalds --- arch/x86/mm/fault.c | 8 +------- 1 file changed, 1 insertion(+), 7 deletions(-) diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index d973e61e450d..d7de5b8657d5 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -844,11 +844,8 @@ do_sigbus(struct pt_regs *regs, unsigned long error_code, unsigned long address, unsigned int fault) { struct task_struct *tsk = current; - struct mm_struct *mm = tsk->mm; int code = BUS_ADRERR; - up_read(&mm->mmap_sem); - /* Kernel mode? Handle exceptions or die: */ if (!(error_code & PF_USER)) { no_context(regs, error_code, address, SIGBUS, BUS_ADRERR); @@ -879,7 +876,6 @@ mm_fault_error(struct pt_regs *regs, unsigned long error_code, unsigned long address, unsigned int fault) { if (fatal_signal_pending(current) && !(error_code & PF_USER)) { - up_read(¤t->mm->mmap_sem); no_context(regs, error_code, address, 0, 0); return; } @@ -887,14 +883,11 @@ mm_fault_error(struct pt_regs *regs, unsigned long error_code, if (fault & VM_FAULT_OOM) { /* Kernel mode? Handle exceptions or die: */ if (!(error_code & PF_USER)) { - up_read(¤t->mm->mmap_sem); no_context(regs, error_code, address, SIGSEGV, SEGV_MAPERR); return; } - up_read(¤t->mm->mmap_sem); - /* * We ran out of memory, call the OOM killer, and return the * userspace (which will retry the fault, or kill us if we got @@ -1247,6 +1240,7 @@ good_area: return; if (unlikely(fault & VM_FAULT_ERROR)) { + up_read(&mm->mmap_sem); mm_fault_error(regs, error_code, address, fault); return; } -- 2.20.1