3.14-stable patches

added patches:
	block-do-a-full-clone-when-splitting-discard-bios.patch

diff --git a/queue-3.14/block-do-a-full-clone-when-splitting-discard-bios.patch b/queue-3.14/block-do-a-full-clone-when-splitting-discard-bios.patch
new file mode 100644 (file)
index 0000000..e3c6e14
--- /dev/null
+++ b/queue-3.14/block-do-a-full-clone-when-splitting-discard-bios.patch
@@ -0,0 +1,64 @@
+From f3f5da624e0a891c34d8cd513c57f1d9b0c7dadc Mon Sep 17 00:00:00 2001
+From: "Martin K. Petersen" <martin.petersen@oracle.com>
+Date: Wed, 22 Jul 2015 07:57:12 -0400
+Subject: block: Do a full clone when splitting discard bios
+
+From: "Martin K. Petersen" <martin.petersen@oracle.com>
+
+commit f3f5da624e0a891c34d8cd513c57f1d9b0c7dadc upstream.
+
+This fixes a data corruption bug when using discard on top of MD linear,
+raid0 and raid10 personalities.
+
+Commit 20d0189b1012 "block: Introduce new bio_split()" permits sharing
+the bio_vec between the two resulting bios. That is fine for read/write
+requests where the bio_vec is immutable. For discards, however, we need
+to be able to attach a payload and update the bio_vec so the page can
+get mapped to a scatterlist entry. Therefore the bio_vec can not be
+shared when splitting discards and we must do a full clone.
+
+Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
+Reported-by: Seunguk Shin <seunguk.shin@samsung.com>
+Tested-by: Seunguk Shin <seunguk.shin@samsung.com>
+Cc: Seunguk Shin <seunguk.shin@samsung.com>
+Cc: Jens Axboe <axboe@fb.com>
+Cc: Kent Overstreet <kent.overstreet@gmail.com>
+Reviewed-by: Christoph Hellwig <hch@lst.de>
+Signed-off-by: Jens Axboe <axboe@fb.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ fs/bio.c |   15 ++++++++++++---
+ 1 file changed, 12 insertions(+), 3 deletions(-)
+
+--- a/fs/bio.c
++++ b/fs/bio.c
+@@ -1806,8 +1806,9 @@ EXPORT_SYMBOL(bio_endio_nodec);
+  * Allocates and returns a new bio which represents @sectors from the start of
+  * @bio, and updates @bio to represent the remaining sectors.
+  *
+- * The newly allocated bio will point to @bio's bi_io_vec; it is the caller's
+- * responsibility to ensure that @bio is not freed before the split.
++ * Unless this is a discard request the newly allocated bio will point
++ * to @bio's bi_io_vec; it is the caller's responsibility to ensure that
++ * @bio is not freed before the split.
+  */
+ struct bio *bio_split(struct bio *bio, int sectors,
+                     gfp_t gfp, struct bio_set *bs)
+@@ -1817,7 +1818,15 @@ struct bio *bio_split(struct bio *bio, i
+       BUG_ON(sectors <= 0);
+       BUG_ON(sectors >= bio_sectors(bio));
+ 
+-      split = bio_clone_fast(bio, gfp, bs);
++      /*
++       * Discards need a mutable bio_vec to accommodate the payload
++       * required by the DSM TRIM and UNMAP commands.
++       */
++      if (bio->bi_rw & REQ_DISCARD)
++              split = bio_clone_bioset(bio, gfp, bs);
++      else
++              split = bio_clone_fast(bio, gfp, bs);
++
+       if (!split)
+               return NULL;
+ 

diff --git a/queue-3.14/series b/queue-3.14/series
index e7e3ce4644e4d1c67a4a6bca7c8210360b6613f3..53aa921fb73f2502e95e980c04a96d90df2c466f 100644 (file)
--- a/queue-3.14/series
+++ b/queue-3.14/series
@@ -107,3 +107,4 @@ clocksource-exynos_mct-avoid-blocking-calls-in-the-cpu-hotplug-notifier.patch
 ideapad-fix-software-rfkill-setting.patch
 dell-laptop-fix-allocating-freeing-smi-buffer-page.patch
 usb-usbfs-allow-urbs-to-be-reaped-after-disconnection.patch
+block-do-a-full-clone-when-splitting-discard-bios.patch