linux/drivers, branch v3.5

Merge tag 'dm-3.5-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-dm

2012-07-20T18:51:22Z

Pull device-mapper discard fixes from Alasdair G Kergon: - avoid a crash in dm-raid1 when discards coincide with mirror recovery; - avoid discarding shared data that's still needed in dm-thin; - don't guarantee that discarded blocks will be wiped in dm-raid1. * tag 'dm-3.5-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-dm: dm raid1: set discard_zeroes_data_unsupported dm thin: do not send discards to shared blocks dm raid1: fix crash with mirror recovery and discard

dm raid1: set discard_zeroes_data_unsupported

2012-07-20T13:25:07Z

We can't guarantee that REQ_DISCARD on dm-mirror zeroes the data even if the underlying disks support zero on discard. So this patch sets ti->discard_zeroes_data_unsupported. For example, if the mirror is in the process of resynchronizing, it may happen that kcopyd reads a piece of data, then discard is sent on the same area and then kcopyd writes the piece of data to another leg. Consequently, the data is not zeroed. The flag was made available by commit 983c7db347db8ce2d8453fd1d89b7a4bb6920d56 (dm crypt: always disable discard_zeroes_data). Signed-off-by: Mikulas Patocka Cc: stable@kernel.org Signed-off-by: Alasdair G Kergon

dm thin: do not send discards to shared blocks

2012-07-20T13:25:05Z

When process_discard receives a partial discard that doesn't cover a full block, it sends this discard down to that block. Unfortunately, the block can be shared and the discard would corrupt the other snapshots sharing this block. This patch detects block sharing and ends the discard with success when sending it to the shared block. The above change means that if the device supports discard it can't be guaranteed that a discard request zeroes data. Therefore, we set ti->discard_zeroes_data_unsupported. Thin target discard support with this bug arrived in commit 104655fd4dcebd50068ef30253a001da72e3a081 (dm thin: support discards). Signed-off-by: Mikulas Patocka Cc: stable@kernel.org Signed-off-by: Mike Snitzer Signed-off-by: Alasdair G Kergon

dm raid1: fix crash with mirror recovery and discard

2012-07-20T13:25:03Z

This patch fixes a crash when a discard request is sent during mirror recovery. Firstly, some background. Generally, the following sequence happens during mirror synchronization: - function do_recovery is called - do_recovery calls dm_rh_recovery_prepare - dm_rh_recovery_prepare uses a semaphore to limit the number simultaneously recovered regions (by default the semaphore value is 1, so only one region at a time is recovered) - dm_rh_recovery_prepare calls __rh_recovery_prepare, __rh_recovery_prepare asks the log driver for the next region to recover. Then, it sets the region state to DM_RH_RECOVERING. If there are no pending I/Os on this region, the region is added to quiesced_regions list. If there are pending I/Os, the region is not added to any list. It is added to the quiesced_regions list later (by dm_rh_dec function) when all I/Os finish. - when the region is on quiesced_regions list, there are no I/Os in flight on this region. The region is popped from the list in dm_rh_recovery_start function. Then, a kcopyd job is started in the recover function. - when the kcopyd job finishes, recovery_complete is called. It calls dm_rh_recovery_end. dm_rh_recovery_end adds the region to recovered_regions or failed_recovered_regions list (depending on whether the copy operation was successful or not). The above mechanism assumes that if the region is in DM_RH_RECOVERING state, no new I/Os are started on this region. When I/O is started, dm_rh_inc_pending is called, which increases reg->pending count. When I/O is finished, dm_rh_dec is called. It decreases reg->pending count. If the count is zero and the region was in DM_RH_RECOVERING state, dm_rh_dec adds it to the quiesced_regions list. Consequently, if we call dm_rh_inc_pending/dm_rh_dec while the region is in DM_RH_RECOVERING state, it could be added to quiesced_regions list multiple times or it could be added to this list when kcopyd is copying data (it is assumed that the region is not on any list while kcopyd does its jobs). This results in memory corruption and crash. There already exist bypasses for REQ_FLUSH requests: REQ_FLUSH requests do not belong to any region, so they are always added to the sync list in do_writes. dm_rh_inc_pending does not increase count for REQ_FLUSH requests. In mirror_end_io, dm_rh_dec is never called for REQ_FLUSH requests. These bypasses avoid the crash possibility described above. These bypasses were improperly implemented for REQ_DISCARD when the mirror target gained discard support in commit 5fc2ffeabb9ee0fc0e71ff16b49f34f0ed3d05b4 (dm raid1: support discard). In do_writes, REQ_DISCARD requests is always added to the sync queue and immediately dispatched (even if the region is in DM_RH_RECOVERING). However, dm_rh_inc and dm_rh_dec is called for REQ_DISCARD resusts. So it violates the rule that no I/Os are started on DM_RH_RECOVERING regions, and causes the list corruption described above. This patch changes it so that REQ_DISCARD requests follow the same path as REQ_FLUSH. This avoids the crash. Reference: https://bugzilla.redhat.com/837607 Signed-off-by: Mikulas Patocka Cc: stable@kernel.org Signed-off-by: Alasdair G Kergon

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client

2012-07-19T23:11:28Z

Pull last minute Ceph fixes from Sage Weil: "The important one fixes a bug in the socket failure handling behavior that was turned up in some recent failure injection testing. The other two are minor bug fixes." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: rbd: endian bug in rbd_req_cb() rbd: Fix ceph_snap_context size calculation libceph: fix messenger retry

Merge tag 'md-3.5-fixes' of git://neil.brown.name/md

2012-07-19T15:27:13Z

Pull three md bugfixes from NeilBrown: "One of the bugs was introduced in 3.5-rc1. Others have been there for longer." * tag 'md-3.5-fixes' of git://neil.brown.name/md: md/raid1: close some possible races on write errors during resync md: avoid crash when stopping md array races with closing other open fds. md: fix bug in handling of new_data_offset

Merge branch 'upstream-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid

2012-07-19T15:15:55Z

Pull HID update from Jiri Kosina: "A final round of changes for HID for 3.5: just device ID additions." * 'upstream-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid: HID: hid-multitouch: add support for Zytronic panels HID: add Sennheiser BTD500USB device support HID: add battery quirk for Apple Wireless ANSI

cx25821: Remove bad strcpy to read-only char*

2012-07-19T15:15:33Z

The strcpy was being used to set the name of the board. Since the destination char* was read-only and the name is set statically at compile time; this was both wrong and redundant. The type of char* is changed to const char* to prevent future errors. Reported-by: Radek Masin Signed-off-by: Ezequiel Garcia [ Taking directly due to vacations - Linus ] Signed-off-by: Linus Torvalds

HID: hid-multitouch: add support for Zytronic panels

2012-07-19T11:56:16Z

Signed-off-by: Benjamin Tissoires Signed-off-by: Jiri Kosina

md/raid1: close some possible races on write errors during resync

2012-07-19T05:59:18Z

commit 4367af556133723d0f443e14ca8170d9447317cb md/raid1: clear bad-block record when write succeeds. Added a 'reschedule_retry' call possibility at the end of end_sync_write, but didn't add matching code at the end of sync_request_write. So if the writes complete very quickly, or scheduling makes it seem that way, then we can miss rescheduling the request and the resync could hang. Also commit 73d5c38a9536142e062c35997b044e89166e063b md: avoid races when stopping resync. Fix a race condition in this same code in end_sync_write but didn't make the change in sync_request_write. This patch updates sync_request_write to fix both of those. Patch is suitable for 3.1 and later kernels. Reported-by: Alexander Lyakas Original-version-by: Alexander Lyakas Cc: stable@vger.kernel.org Signed-off-by: NeilBrown