linux-stable.git/drivers/block, branch linux-3.17.y

zram: avoid kunmap_atomic() of a NULL pointer

2014-11-21T17:23:08+00:00

commit c406515239376fc93a30d5d03192182160cbd3fb upstream.

zram could kunmap_atomic() a NULL pointer in a rare situation: a zram
page becomes a full-zeroed page after a partial write io.  The current
code doesn't handle this case and performs kunmap_atomic() on a NULL
pointer, which panics the kernel.

This patch fixes this issue.

Signed-off-by: Weijie Yang 
Cc: Sergey Senozhatsky 
Cc: Dan Streetman 
Cc: Nitin Gupta 
Cc: Weijie Yang 
Acked-by: Jerome Marchand 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

sunvdc: don't call VD_OP_GET_VTOC

2014-11-21T17:23:08+00:00

[ Upstream commit 85b0c6e62c48bb9179fd5b3e954f362fb346cbd5 ]

The VD_OP_GET_VTOC operation will succeed only if the vdisk backend has a
VTOC label, otherwise it will fail. In particular, it will return error
48 (ENOTSUP) if the disk has an EFI label. VTOC disk labels are already
handled by directly reading the disk in block/partitions/sun.c (enabled by
CONFIG_SUN_PARTITION which defaults to y on SPARC). Since port->label is
unused in the driver, remove the call and the field.

Signed-off-by: Dwight Engen 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

vio: fix reuse of vio_dring slot

2014-11-21T17:23:08+00:00

[ Upstream commit d0aedcd4f14a22e23b313f42b7e6e6ebfc0fbc31 ]

vio_dring_avail() will allow use of every dring entry, but when the last
entry is allocated then dr->prod == dr->cons which is indistinguishable from
the ring empty condition. This causes the next allocation to reuse an entry.
When this happens in sunvdc, the server side vds driver begins nack'ing the
messages and ends up resetting the ldc channel. This problem does not effect
sunvnet since it checks for < 2.

The fix here is to just never allocate the very last dring slot so that full
and empty are not the same condition. The request start path was changed to
check for the ring being full a bit earlier, and to stop the blk_queue if
there is no space left. The blk_queue will be restarted once the ring is
only half full again. The number of ring entries was increased to 512 which
matches the sunvnet and Solaris vdc drivers, and greatly reduces the
frequency of hitting the ring full condition and the associated blk_queue
stop/starting. The checks in sunvent were adjusted to account for
vio_dring_avail() returning 1 less.

Orabug: 19441666
OraBZ: 14983

Signed-off-by: Dwight Engen 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

sunvdc: limit each sg segment to a page

2014-11-21T17:23:08+00:00

[ Upstream commit 5eed69ffd248c9f68f56c710caf07db134aef28b ]

ldc_map_sg() could fail its check that the number of pages referred to
by the sg scatterlist was <= the number of cookies.

This fixes the issue by doing a similar thing to the xen-blkfront driver,
ensuring that the scatterlist will only ever contain a segment count <=
port->ring_cookies, and each segment will be page aligned, and <= page
size. This ensures that the scatterlist is always mappable.

Orabug: 19347817
OraBZ: 15945

Signed-off-by: Dwight Engen 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

sunvdc: compute vdisk geometry from capacity

2014-11-21T17:23:08+00:00

[ Upstream commit de5b73f08468b4fc5e2f6d1505f650262622f78b ]

The LDom diskserver doesn't return reliable geometry data. In addition,
the types for all fields in the vio_disk_geom are u16, which were being
truncated in the cast into the u8's of the Linux struct hd_geometry.

Modify vdc_getgeo() to compute the geometry from the disk's capacity in a
manner consistent with xen-blkfront::blkif_getgeo().

Signed-off-by: Dwight Engen 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

sunvdc: add cdrom and v1.1 protocol support

2014-11-21T17:23:08+00:00

[ Upstream commit 9bce21828d54a95143f1b74619705c2dd8e88b92 ]

Interpret the media type from v1.1 protocol to support CDROM/DVD.

For v1.0 protocol, a disk's size continues to be calculated from the
geometry returned by the vdisk server. The geometry returned by the server
can be less than the actual number of sectors available in the backing
image/device due to the rounding in the division used to compute the
geometry in the vdisk server.

In v1.1 protocol a disk's actual size in sectors is returned during the
handshake. Use this size when v1.1 protocol is negotiated. Since this size
will always be larger than the former geometry computed size, disks created
under v1.0 will be forwards compatible to v1.1, but not vice versa.

Signed-off-by: Dwight Engen 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

rbd: Fix error recovery in rbd_obj_read_sync()

2014-11-14T18:10:39+00:00

commit a8d4205623ae965e36c68629db306ca0695a2771 upstream.

When we fail to allocate page vector in rbd_obj_read_sync() we just
basically ignore the problem and continue which will result in an oops
later. Fix the problem by returning proper error.

CC: Yehuda Sadeh 
CC: Sage Weil 
CC: ceph-devel@vger.kernel.org
Coverity-id: 1226882
Signed-off-by: Jan Kara 
Signed-off-by: Ilya Dryomov 
Signed-off-by: Greg Kroah-Hartman

drbd: compute the end before rb_insert_augmented()

2014-11-14T18:10:26+00:00

commit 82cfb90bc99d7b7e0ec62d0505b9d4f06805d5db upstream.

Commit 98683650 "Merge branch 'drbd-8.4_ed6' into
for-3.8-drivers-drbd-8.4_ed6" switches to the new augment API, but the
new API requires that the tree is augmented before rb_insert_augmented()
is called, which is missing.

So we add the augment-code to drbd_insert_interval() when it travels the
tree up to down before rb_insert_augmented().  See the example in
include/linux/interval_tree_generic.h or Documentation/rbtree.txt.

drbd_insert_interval() may cancel the insertion when traveling, in this
case, the just added augment-code does nothing before cancel since the
@this node is already in the subtrees in this case.

CC: Michel Lespinasse 
Signed-off-by: Lai Jiangshan 
Signed-off-by: Andreas Gruenbacher 
Signed-off-by: Philipp Reisner 
Signed-off-by: Jens Axboe 
Signed-off-by: Greg Kroah-Hartman

xen-blkback: fix leak on grant map error path

2014-11-14T18:10:25+00:00

commit 61cecca865280bef4f8a9748d0a9afa5df351ac2 upstream.

Fix leaking a page when a grant mapping has failed.

Signed-off-by: Roger Pau Monné 
Reported-and-Tested-by: Tao Chen 
Signed-off-by: Konrad Rzeszutek Wilk 
Signed-off-by: Greg Kroah-Hartman

xen/blkback: unmap all persistent grants when frontend gets disconnected

2014-11-14T18:10:25+00:00

commit 12ea729645ace01e08f9654df155622898d3aae6 upstream.

blkback does not unmap persistent grants when frontend goes to Closed
state (e.g. when blkfront module is being removed). This leads to the
following in guest's dmesg:

[  343.243825] xen:grant_table: WARNING: g.e. 0x445 still in use!
[  343.243825] xen:grant_table: WARNING: g.e. 0x42a still in use!
...

When load module -> use device -> unload module sequence is performed multiple times
it is possible to hit BUG() condition in blkfront module:

[  343.243825] kernel BUG at drivers/block/xen-blkfront.c:954!
[  343.243825] invalid opcode: 0000 [#1] SMP
[  343.243825] Modules linked in: xen_blkfront(-) ata_generic pata_acpi [last unloaded: xen_blkfront]
...
[  343.243825] Call Trace:
[  343.243825]  [] ? unregister_xenbus_watch+0x16f/0x1e0
[  343.243825]  [] blkfront_remove+0x3f/0x140 [xen_blkfront]
...
[  343.243825] RIP  [] blkif_free+0x34e/0x360 [xen_blkfront]
[  343.243825]  RSP 

We don't need to keep these grants if we're disconnecting as frontend might already
forgot about them. Solve the issue by moving xen_blkbk_free_caches() call from
xen_blkif_free() to xen_blkif_disconnect().

Now we can see the following:
[  928.590893] xen:grant_table: WARNING: g.e. 0x587 still in use!
[  928.591861] xen:grant_table: WARNING: g.e. 0x372 still in use!
...
[  929.592146] xen:grant_table: freeing g.e. 0x587
[  929.597174] xen:grant_table: freeing g.e. 0x372
...

Backend does not keep persistent grants any more, reconnect works fine.

Signed-off-by: Vitaly Kuznetsov 
Signed-off-by: Konrad Rzeszutek Wilk 
Signed-off-by: Greg Kroah-Hartman