Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus

Pull MIPS fixes from Ralf Baechle:
 "What's in there: a number of MIPS fixes and touchups.  The most
  important change in this pull request is Kautuk Consul's port of
  changes to do_page_fault which fix a hang that affects some
  configurations.  Still not quite ready for a release, there are
  problems with 64-bit platforms."

* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus:
  MIPS: traps.c: Fix typo
  MIPS: PowerTV: Fix defconfigs for coverage builds
  MIPS: Netlogic: Fix defconfigs for coverage builds
  MIPS: ATH79: Avoid a kernel bug on AR913X
  MIPS: PCI: use list_for_each_entry() for bus->devices traversal
  MIPS: fault.c: Port OOM changes to do_page_fault
  MIPS: vmlinux.lds.S: remove duplicate _sdata symbol
  MIPS: Alchemy: Increase minimum timeout for 32kHz timer.
  MIPS: txx9 7segled fix struct device has no member
  MIPS: Alchemy: Update Au1300 inlined GPIO macros
  MIPS: Remove temporary kludge from <asm/page.h>
  MIPS: BMIPS: smp-bmips.c does not need to include version.h

1 files changed, 29 insertions, 7 deletions

diff --git a/arch/mips/mm/fault.c b/arch/mips/mm/fault.c
index 937cf336816..69ebd586d7f 100644
--- a/arch/mips/mm/fault.c
+++ b/arch/mips/mm/fault.c
@@ -42,6 +42,8 @@ asmlinkage void __kprobes do_page_fault(struct pt_regs *regs, unsigned long writ
 	const int field = sizeof(unsigned long) * 2;
 	siginfo_t info;
 	int fault;
+	unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE |
+						 (write ? FAULT_FLAG_WRITE : 0);
 
 #if 0
 	printk("Cpu%d[%s:%d:%0*lx:%ld:%0*lx]\n", raw_smp_processor_id(),
@@ -91,6 +93,7 @@ asmlinkage void __kprobes do_page_fault(struct pt_regs *regs, unsigned long writ
 	if (in_atomic() || !mm)
 		goto bad_area_nosemaphore;
 
+retry:
 	down_read(&mm->mmap_sem);
 	vma = find_vma(mm, address);
 	if (!vma)
@@ -144,7 +147,11 @@ good_area:
 	 * make sure we exit gracefully rather than endlessly redo
 	 * the fault.
 	 */
-	fault = handle_mm_fault(mm, vma, address, write ? FAULT_FLAG_WRITE : 0);
+	fault = handle_mm_fault(mm, vma, address, flags);
+
+	if ((fault & VM_FAULT_RETRY) && fatal_signal_pending(current))
+		return;
+
 	perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address);
 	if (unlikely(fault & VM_FAULT_ERROR)) {
 		if (fault & VM_FAULT_OOM)
@@ -153,12 +160,27 @@ good_area:
 			goto do_sigbus;
 		BUG();
 	}
-	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 (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;
+
+			/*
+			 * No need to up_read(&mm->mmap_sem) as we would
+			 * have already released it in __lock_page_or_retry
+			 * in mm/filemap.c.
+			 */
+
+			goto retry;
+		}
 	}
 
 	up_read(&mm->mmap_sem);