diff options
Diffstat (limited to 'arch/mips/mm/fault.c')
| -rw-r--r-- | arch/mips/mm/fault.c | 74 |
1 files changed, 33 insertions, 41 deletions
diff --git a/arch/mips/mm/fault.c b/arch/mips/mm/fault.c index 1e8d00793784..aaa9a242ebba 100644 --- a/arch/mips/mm/fault.c +++ b/arch/mips/mm/fault.c @@ -26,6 +26,7 @@ #include <asm/mmu_context.h> #include <asm/ptrace.h> #include <asm/highmem.h> /* For VMALLOC_END */ +#include <asm/traps.h> #include <linux/kdebug.h> int show_unhandled_signals = 1; @@ -35,7 +36,7 @@ int show_unhandled_signals = 1; * and the problem, and then passes it off to one of the appropriate * routines. */ -static void __kprobes __do_page_fault(struct pt_regs *regs, unsigned long write, +static void __do_page_fault(struct pt_regs *regs, unsigned long write, unsigned long address) { struct vm_area_struct * vma = NULL; @@ -44,7 +45,7 @@ static void __kprobes __do_page_fault(struct pt_regs *regs, unsigned long write, const int field = sizeof(unsigned long) * 2; int si_code; vm_fault_t fault; - unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE; + unsigned int flags = FAULT_FLAG_DEFAULT; static DEFINE_RATELIMIT_STATE(ratelimit_state, 5 * HZ, 10); @@ -96,22 +97,16 @@ static void __kprobes __do_page_fault(struct pt_regs *regs, unsigned long write, if (user_mode(regs)) flags |= FAULT_FLAG_USER; + + perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address); retry: - down_read(&mm->mmap_sem); - vma = find_vma(mm, address); + vma = lock_mm_and_find_vma(mm, address, regs); if (!vma) - goto bad_area; - if (vma->vm_start <= address) - goto good_area; - if (!(vma->vm_flags & VM_GROWSDOWN)) - goto bad_area; - if (expand_stack(vma, address)) - goto bad_area; + goto bad_area_nosemaphore; /* * Ok, we have a good vm_area for this memory access, so * we can handle it.. */ -good_area: si_code = SEGV_ACCERR; if (write) { @@ -142,7 +137,7 @@ good_area: goto bad_area; } } else { - if (!(vma->vm_flags & (VM_READ | VM_WRITE | VM_EXEC))) + if (unlikely(!vma_is_accessible(vma))) goto bad_area; } } @@ -152,12 +147,18 @@ good_area: * make sure we exit gracefully rather than endlessly redo * the fault. */ - fault = handle_mm_fault(vma, address, flags); + fault = handle_mm_fault(vma, address, flags, regs); - if ((fault & VM_FAULT_RETRY) && fatal_signal_pending(current)) + if (fault_signal_pending(fault, regs)) { + if (!user_mode(regs)) + goto no_context; + return; + } + + /* The fault is fully completed (including releasing mmap lock) */ + if (fault & VM_FAULT_COMPLETED) return; - perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address); if (unlikely(fault & VM_FAULT_ERROR)) { if (fault & VM_FAULT_OOM) goto out_of_memory; @@ -167,31 +168,20 @@ good_area: goto do_sigbus; BUG(); } - if (flags & FAULT_FLAG_ALLOW_RETRY) { - if (fault & VM_FAULT_MAJOR) { - perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MAJ, 1, - regs, address); - tsk->maj_flt++; - } else { - perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MIN, 1, - regs, address); - tsk->min_flt++; - } - if (fault & VM_FAULT_RETRY) { - flags &= ~FAULT_FLAG_ALLOW_RETRY; - flags |= FAULT_FLAG_TRIED; - /* - * No need to up_read(&mm->mmap_sem) as we would - * have already released it in __lock_page_or_retry - * in mm/filemap.c. - */ + if (fault & VM_FAULT_RETRY) { + flags |= FAULT_FLAG_TRIED; - goto retry; - } + /* + * No need to mmap_read_unlock(mm) as we would + * have already released it in __lock_page_or_retry + * in mm/filemap.c. + */ + + goto retry; } - up_read(&mm->mmap_sem); + mmap_read_unlock(mm); return; /* @@ -199,7 +189,7 @@ good_area: * Fix it, but check if it's kernel or user first.. */ bad_area: - up_read(&mm->mmap_sem); + mmap_read_unlock(mm); bad_area_nosemaphore: /* User mode accesses just cause a SIGSEGV */ @@ -251,14 +241,14 @@ out_of_memory: * We ran out of memory, call the OOM killer, and return the userspace * (which will retry the fault, or kill us if we got oom-killed). */ - up_read(&mm->mmap_sem); + mmap_read_unlock(mm); if (!user_mode(regs)) goto no_context; pagefault_out_of_memory(); return; do_sigbus: - up_read(&mm->mmap_sem); + mmap_read_unlock(mm); /* Kernel mode? Handle exceptions or die */ if (!user_mode(regs)) @@ -329,8 +319,9 @@ vmalloc_fault: } #endif } +NOKPROBE_SYMBOL(__do_page_fault); -asmlinkage void __kprobes do_page_fault(struct pt_regs *regs, +asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long write, unsigned long address) { enum ctx_state prev_state; @@ -339,3 +330,4 @@ asmlinkage void __kprobes do_page_fault(struct pt_regs *regs, __do_page_fault(regs, write, address); exception_exit(prev_state); } +NOKPROBE_SYMBOL(do_page_fault); |