Merge tag 'v4.12-rc6' into patchwork

Linux 4.12-rc6

* tag 'v4.12-rc6': (813 commits)
  Linux 4.12-rc6
  mm: larger stack guard gap, between vmas
  virtio_balloon: disable VIOMMU support
  mm: correct the comment when reclaimed pages exceed the scanned pages
  userfaultfd: shmem: handle coredumping in handle_userfault()
  mm: numa: avoid waiting on freed migrated pages
  swap: cond_resched in swap_cgroup_prepare()
  mm/memory-failure.c: use compound_head() flags for huge pages
  perf unwind: Report module before querying isactivation in dwfl unwind
  fs: pass on flags in compat_writev
  objtool: Add fortify_panic as __noreturn function
  powerpc/debug: Add missing warn flag to WARN_ON's non-builtin path
  USB: gadgetfs, dummy-hcd, net2280: fix locking for callbacks
  drm: mxsfb_crtc: Reset the eLCDIF controller
  drm/mgag200: Fix to always set HiPri for G200e4 V2
  i2c: ismt: fix wrong device address when unmap the data buffer
  i2c: rcar: use correct length when unmapping DMA
  powerpc/xive: Fix offset for store EOI MMIOs
  drm/tegra: Correct idr_alloc() minimum id
  drm/tegra: Fix lockup on a use of staging API
  ...

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

1 files changed, 8 insertions, 17 deletions

diff --git a/mm/gup.c b/mm/gup.c
index d9e6fddcc51f..576c4df58882 100644
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -387,11 +387,6 @@ static int faultin_page(struct task_struct *tsk, struct vm_area_struct *vma,
 	/* mlock all present pages, but do not fault in new pages */
 	if ((*flags & (FOLL_POPULATE | FOLL_MLOCK)) == FOLL_MLOCK)
 		return -ENOENT;
-	/* For mm_populate(), just skip the stack guard page. */
-	if ((*flags & FOLL_POPULATE) &&
-			(stack_guard_page_start(vma, address) ||
-			 stack_guard_page_end(vma, address + PAGE_SIZE)))
-		return -ENOENT;
 	if (*flags & FOLL_WRITE)
 		fault_flags |= FAULT_FLAG_WRITE;
 	if (*flags & FOLL_REMOTE)
@@ -407,12 +402,10 @@ static int faultin_page(struct task_struct *tsk, struct vm_area_struct *vma,
 
 	ret = handle_mm_fault(vma, address, fault_flags);
 	if (ret & VM_FAULT_ERROR) {
-		if (ret & VM_FAULT_OOM)
-			return -ENOMEM;
-		if (ret & (VM_FAULT_HWPOISON | VM_FAULT_HWPOISON_LARGE))
-			return *flags & FOLL_HWPOISON ? -EHWPOISON : -EFAULT;
-		if (ret & (VM_FAULT_SIGBUS | VM_FAULT_SIGSEGV))
-			return -EFAULT;
+		int err = vm_fault_to_errno(ret, *flags);
+
+		if (err)
+			return err;
 		BUG();
 	}
 
@@ -723,12 +716,10 @@ retry:
 	ret = handle_mm_fault(vma, address, fault_flags);
 	major |= ret & VM_FAULT_MAJOR;
 	if (ret & VM_FAULT_ERROR) {
-		if (ret & VM_FAULT_OOM)
-			return -ENOMEM;
-		if (ret & (VM_FAULT_HWPOISON | VM_FAULT_HWPOISON_LARGE))
-			return -EHWPOISON;
-		if (ret & (VM_FAULT_SIGBUS | VM_FAULT_SIGSEGV))
-			return -EFAULT;
+		int err = vm_fault_to_errno(ret, 0);
+
+		if (err)
+			return err;
 		BUG();
 	}