[PATCH 4.4 02/45] thp: fix MADV_DONTNEED vs clear soft dirty race

From	Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Newsgroups	linux.kernel
Subject	[PATCH 4.4 02/45] thp: fix MADV_DONTNEED vs clear soft dirty race
Date	2017-04-19 17:10 +0200
Message-ID	<txZp2-4Zt-63@gated-at.bofh.it> (permalink)
References	<txZfj-4Gn-5@gated-at.bofh.it>
Organization	linux.* mail to news gateway

Show all headers | View raw

4.4-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>

commit 5b7abeae3af8c08c577e599dd0578b9e3ee6687b upstream.

Yet another instance of the same race.

Fix is identical to change_huge_pmd().

See "thp: fix MADV_DONTNEED vs.  numa balancing race" for more details.

Link: http://lkml.kernel.org/r/20170302151034.27829-5-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 fs/proc/task_mmu.c |    9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -803,7 +803,14 @@ static inline void clear_soft_dirty(stru
 static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma,
 		unsigned long addr, pmd_t *pmdp)
 {
-	pmd_t pmd = pmdp_huge_get_and_clear(vma->vm_mm, addr, pmdp);
+	pmd_t pmd = *pmdp;
+
+	/* See comment in change_huge_pmd() */
+	pmdp_invalidate(vma, addr, pmdp);
+	if (pmd_dirty(*pmdp))
+		pmd = pmd_mkdirty(pmd);
+	if (pmd_young(*pmdp))
+		pmd = pmd_mkyoung(pmd);
 
 	pmd = pmd_wrprotect(pmd);
 	pmd = pmd_clear_soft_dirty(pmd);

Thread

[PATCH 4.4 00/45] 4.4.63-stable review Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-04-19 17:00 +0200
  [PATCH 4.4 44/45] sctp: deny peeloff operation on asocs with threads sleeping on it Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-04-19 17:00 +0200
  [PATCH 4.4 32/45] mm: Tighten x86 /dev/mem with zeroing reads Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-04-19 17:00 +0200
  [PATCH 4.4 16/45] xen, fbfront: fix connecting to backend Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-04-19 17:10 +0200
  [PATCH 4.4 15/45] scsi: sd: Fix capacity calculation with 32-bit sector_t Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-04-19 17:10 +0200
  [PATCH 4.4 27/45] ath9k: fix NULL pointer dereference Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-04-19 17:10 +0200
  [PATCH 4.4 20/45] char: Drop bogus dependency of DEVPORT on !M68K Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-04-19 17:10 +0200
  [PATCH 4.4 11/45] iscsi-target: Fix TMR reference leak during session shutdown Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-04-19 17:10 +0200
  [PATCH 4.4 23/45] kvm: fix page struct leak in handle_vmon Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-04-19 17:10 +0200
  [PATCH 4.4 12/45] iscsi-target: Drop work-around for legacy GlobalSAN initiator Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-04-19 17:10 +0200
  [PATCH 4.4 10/45] acpi, nfit, libnvdimm: fix interleave set cookie calculation (64-bit comparison) Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-04-19 17:10 +0200
  [PATCH 4.4 14/45] scsi: sd: Consider max_xfer_blocks if opt_xfer_blocks is unusable Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-04-19 17:10 +0200
  [PATCH 4.4 03/45] drm/nouveau/mpeg: mthd returns true on success now Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-04-19 17:10 +0200
  [PATCH 4.4 06/45] Input: xpad - add support for Razer Wildcat gamepad Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-04-19 17:10 +0200
  [PATCH 4.4 39/45] catc: Use heap buffer for memory size test Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-04-19 17:10 +0200
  [PATCH 4.4 25/45] powerpc: Disable HFSCR[TM] if TM is not supported Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-04-19 17:10 +0200
  [PATCH 4.4 07/45] perf/x86: Avoid exposing wrong/stale data in intel_pmu_lbr_read_32() Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-04-19 17:10 +0200
  [PATCH 4.4 41/45] SUNRPC: fix refcounting problems with auth_gss messages. Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-04-19 17:10 +0200
  [PATCH 4.4 02/45] thp: fix MADV_DONTNEED vs clear soft dirty race Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-04-19 17:10 +0200
  [PATCH 4.4 31/45] rtc: tegra: Implement clock handling Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-04-19 17:10 +0200
  [PATCH 4.4 17/45] libnvdimm: fix reconfig_mutex, mmap_sem, and jbd2_handle lockdep splat Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-04-19 17:10 +0200
  [PATCH 4.4 05/45] CIFS: store results of cifs_reopen_file to avoid infinite wait Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-04-19 17:10 +0200
  [PATCH 4.4 08/45] x86/vdso: Ensure vdso32_enabled gets set to valid values only Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-04-19 17:10 +0200
  [PATCH 4.4 40/45] ibmveth: calculate gso_segs for large packets Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-04-19 17:10 +0200
  [PATCH 4.4 21/45] char: lack of bool string made CONFIG_DEVPORT always on Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-04-19 17:10 +0200
  [PATCH 4.4 42/45] tty/serial: atmel: RS485 half duplex w/DMA: enable RX after TX is done Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-04-19 17:10 +0200
  [PATCH 4.4 38/45] catc: Combine failure cleanup code in catc_probe() Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-04-19 17:10 +0200
  [PATCH 4.4 26/45] crypto: ahash - Fix EINPROGRESS notification callback Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-04-19 17:10 +0200
  [PATCH 4.4 01/45] cgroup, kthread: close race window where new kthreads can be migrated to non-root cgroups Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-04-19 17:10 +0200
  Re: [PATCH 4.4 00/45] 4.4.63-stable review Shuah Khan <shuahkh@osg.samsung.com> - 2017-04-19 22:40 +0200
  Re: [PATCH 4.4 00/45] 4.4.63-stable review Guenter Roeck <linux@roeck-us.net> - 2017-04-20 01:30 +0200

csiph-web