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Diffstat (limited to 'arch/x86/mm/fault.c')
-rw-r--r--arch/x86/mm/fault.c49
1 files changed, 39 insertions, 10 deletions
diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
index 20e3f8702d1..0d17c8c50ac 100644
--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -12,10 +12,12 @@
#include <linux/mmiotrace.h> /* kmmio_handler, ... */
#include <linux/perf_event.h> /* perf_sw_event */
#include <linux/hugetlb.h> /* hstate_index_to_shift */
+#include <linux/prefetch.h> /* prefetchw */
#include <asm/traps.h> /* dotraplinkage, ... */
#include <asm/pgalloc.h> /* pgd_*(), ... */
#include <asm/kmemcheck.h> /* kmemcheck_*(), ... */
+#include <asm/vsyscall.h>
/*
* Page fault error code bits:
@@ -104,7 +106,7 @@ check_prefetch_opcode(struct pt_regs *regs, unsigned char *instr,
* but for now it's good enough to assume that long
* mode only uses well known segments or kernel.
*/
- return (!user_mode(regs)) || (regs->cs == __USER_CS);
+ return (!user_mode(regs) || user_64bit_mode(regs));
#endif
case 0x60:
/* 0x64 thru 0x67 are valid prefixes in all modes. */
@@ -719,6 +721,18 @@ __bad_area_nosemaphore(struct pt_regs *regs, unsigned long error_code,
if (is_errata100(regs, address))
return;
+#ifdef CONFIG_X86_64
+ /*
+ * Instruction fetch faults in the vsyscall page might need
+ * emulation.
+ */
+ if (unlikely((error_code & PF_INSTR) &&
+ ((address & ~0xfff) == VSYSCALL_START))) {
+ if (emulate_vsyscall(regs, address))
+ return;
+ }
+#endif
+
if (unlikely(show_unhandled_signals))
show_signal_msg(regs, error_code, address, tsk);
@@ -822,16 +836,30 @@ do_sigbus(struct pt_regs *regs, unsigned long error_code, unsigned long address,
force_sig_info_fault(SIGBUS, code, address, tsk, fault);
}
-static noinline void
+static noinline int
mm_fault_error(struct pt_regs *regs, unsigned long error_code,
unsigned long address, unsigned int fault)
{
+ /*
+ * Pagefault was interrupted by SIGKILL. We have no reason to
+ * continue pagefault.
+ */
+ if (fatal_signal_pending(current)) {
+ if (!(fault & VM_FAULT_RETRY))
+ up_read(&current->mm->mmap_sem);
+ if (!(error_code & PF_USER))
+ no_context(regs, error_code, address);
+ return 1;
+ }
+ if (!(fault & VM_FAULT_ERROR))
+ return 0;
+
if (fault & VM_FAULT_OOM) {
/* Kernel mode? Handle exceptions or die: */
if (!(error_code & PF_USER)) {
up_read(&current->mm->mmap_sem);
no_context(regs, error_code, address);
- return;
+ return 1;
}
out_of_memory(regs, error_code, address);
@@ -842,6 +870,7 @@ mm_fault_error(struct pt_regs *regs, unsigned long error_code,
else
BUG();
}
+ return 1;
}
static int spurious_fault_check(unsigned long error_code, pte_t *pte)
@@ -964,7 +993,7 @@ do_page_fault(struct pt_regs *regs, unsigned long error_code)
struct mm_struct *mm;
int fault;
int write = error_code & PF_WRITE;
- unsigned int flags = FAULT_FLAG_ALLOW_RETRY |
+ unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE |
(write ? FAULT_FLAG_WRITE : 0);
tsk = current;
@@ -1043,7 +1072,7 @@ do_page_fault(struct pt_regs *regs, unsigned long error_code)
if (unlikely(error_code & PF_RSVD))
pgtable_bad(regs, error_code, address);
- perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, 0, regs, address);
+ perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address);
/*
* If we're in an interrupt, have no user context or are running
@@ -1132,9 +1161,9 @@ good_area:
*/
fault = handle_mm_fault(mm, vma, address, flags);
- if (unlikely(fault & VM_FAULT_ERROR)) {
- mm_fault_error(regs, error_code, address, fault);
- return;
+ if (unlikely(fault & (VM_FAULT_RETRY|VM_FAULT_ERROR))) {
+ if (mm_fault_error(regs, error_code, address, fault))
+ return;
}
/*
@@ -1145,11 +1174,11 @@ good_area:
if (flags & FAULT_FLAG_ALLOW_RETRY) {
if (fault & VM_FAULT_MAJOR) {
tsk->maj_flt++;
- perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MAJ, 1, 0,
+ perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MAJ, 1,
regs, address);
} else {
tsk->min_flt++;
- perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MIN, 1, 0,
+ perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MIN, 1,
regs, address);
}
if (fault & VM_FAULT_RETRY) {