+ devmem-fix-kmem-write-bug-on-memory-holes.patch added to -mm tree

+ devmem-fix-kmem-write-bug-on-memory-holes.patch added to -mm tree

[akpm]

The patch titled
     devmem: fix kmem write bug on memory holes
has been added to the -mm tree.  Its filename is
     devmem-fix-kmem-write-bug-on-memory-holes.patch

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------------------------------------------------------
Subject: devmem: fix kmem write bug on memory holes
From: Wu Fengguang <fengguang.wu@intel.com>

write_kmem() used to assume vwrite() always return the full buffer length.
 However now vwrite() could return 0 to indicate memory hole.  This
creates a bug that "buf" is not advanced accordingly.

Fix it to simply ignore the return value, hence the memory hole.

Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Tejun Heo <tj@kernel.org>
Cc: Nick Piggin <npiggin@suse.de>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 drivers/char/mem.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff -puN drivers/char/mem.c~devmem-fix-kmem-write-bug-on-memory-holes drivers/char/mem.c
--- a/drivers/char/mem.c~devmem-fix-kmem-write-bug-on-memory-holes
+++ a/drivers/char/mem.c
@@ -555,7 +555,7 @@ static ssize_t write_kmem(struct file * 
 				err = -EFAULT;
 				break;
 			}
-			sz = vwrite(kbuf, (char *)p, sz);
+			vwrite(kbuf, (char *)p, sz);
 			count -= sz;
 			buf += sz;
 			virtr += sz;
_

Patches currently in -mm which might be from fengguang.wu@intel.com are

linux-next.patch
devmem-check-vmalloc-address-on-kmem-read-write.patch
devmem-fix-kmem-write-bug-on-memory-holes.patch
mm-introduce-dump_page-and-print-symbolic-flag-names.patch
vmscan-check-high-watermark-after-shrink-zone.patch
vmscan-check-high-watermark-after-shrink-zone-fix.patch
mm-restore-zone-all_unreclaimable-to-independence-word.patch
mm-restore-zone-all_unreclaimable-to-independence-word-fix.patch
mm-restore-zone-all_unreclaimable-to-independence-word-fix-2.patch
memory-hotplug-create-sys-firmware-memmap-entry-for-new-memory.patch
memory-hotplug-create-sys-firmware-memmap-entry-for-new-memory-fix.patch
resources-introduce-generic-page_is_ram.patch
resources-introduce-generic-page_is_ram-fix.patch
x86-remove-bios-data-range-from-e820.patch
x86-use-the-generic-page_is_ram.patch
vfs-take-f_lock-on-modifying-f_mode-after-open-time.patch
readahead-introduce-fmode_random-for-posix_fadv_random.patch