This patch prevents the multipath target from changing the device
handler once it has been set on a device. This avoids a kernel crash
that can happen when changing it.
When we reload a multipath device, there are two instances of the
multipath target - the first instance that is active and the second
instance that is being constructed with "ctr" method.
If the multipath constructor finds out that the device is using a
different device handler, it detaches the existing handler and attaches a
new handler. However, the first instance of the multipath target still
exists and processes requests. If the first instance sends some
path-management request with scsi_dh_activate and the second instance
detaches the device handler while the path-management request is in
flight, a crash happens. The reason for the crash is that the endio
routine for the path-management request is working with structures that
were freed when the handler was detached.
There is no practical need to change device handlers on an active device,
so this patch disables it.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Cc: stable@vger.kernel.org Acked-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
// FIXME Make relevant parts of bugzillas (with kernel error messages) public
Mike Snitzer [Wed, 3 Apr 2013 22:52:22 +0000 (09:52 +1100)]
A recent patch to fix the dm cache target's writethrough mode extended
the bio's front_pad to include a 1056-byte struct dm_bio_details.
Writeback mode doesn't need this, so this patch reduces the
per_bio_data_size to 16 bytes in this case instead of 1096.
The dm_bio_details structure was added in "dm cache: fix writes to
cache device in writethrough mode" which fixed commit e2e74d617e ("dm
cache: fix race in writethrough implementation"). In writeback mode
we avoid allocating the writethrough-specific members of the
per_bio_data structure (the dm_bio_details structure included).
Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Ville Syrjälä [Tue, 2 Apr 2013 13:10:10 +0000 (16:10 +0300)]
drm/i915: Don't use the HDMI port color range bit on Valleyview
VLV docs still list the the color range selection bit for the HDMI
ports, but for DP ports it has been repurposed.
I have no idea whether the HDMI color range selection bit still works
on VLV, but since we now have to use the PIPECONF color range bit for
DP, we might as well do the same for HDMI.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Reviewed-by: Jani Nikula <jani.nikula@intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Ville Syrjälä [Tue, 2 Apr 2013 13:10:09 +0000 (16:10 +0300)]
drm/i915: Set PIPECONF color range bit on Valleyview
VLV has the color range selection bit in the PIPECONF register.
Configure it appropriately.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Reviewed-by: Jani Nikula <jani.nikula@intel.com>
[danvet: fixup rebase issues due to slightly different baseline.] Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Asai Thambi S P [Wed, 3 Apr 2013 14:26:21 +0000 (19:56 +0530)]
mtip32xx: Add debugfs entry device_status
This patch adds a new debugfs entry 'device_status' in
/sys/kernel/debug/rssd. The value of this entry shows
devices online and those in the process of removing.
Signed-off-by: Sam Bradshaw <sbradshaw@micron.com> Signed-off-by: Asai Thambi S P <asamymuthupa@micron.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
Asai Thambi S P [Wed, 3 Apr 2013 14:23:07 +0000 (19:53 +0530)]
mtip32xx: recovery from command timeout
To recover from command timeouts, reset the device. In addition
to that improved timeout handling of PIO commands.
Signed-off-by: Sam Bradshaw <sbradshaw@micron.com> Signed-off-by: Asai Thambi S P <asamymuthupa@micron.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
block: avoid using uninitialized value in from queue_var_store
As found by gcc-4.8, the QUEUE_SYSFS_BIT_FNS macro creates functions
that use a value generated by queue_var_store independent of whether
that value was set or not.
block/blk-sysfs.c: In function 'queue_store_nonrot':
block/blk-sysfs.c:244:385: warning: 'val' may be used uninitialized in this function [-Wmaybe-uninitialized]
Unlike most other such warnings, this one is not a false positive,
writing any non-number string into the sysfs files indeed has
an undefined result, rather than returning an error.
projects / karo-tx-linux.git / log