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| author | Kay Sievers <kay.sievers@vrfy.org> | 2011-06-30 17:03:48 +0400 |
|---|---|---|
| committer | James Bottomley <JBottomley@Parallels.com> | 2011-07-22 01:15:58 +0400 |
| commit | 79b9677d885d1a792bc103f2febb06f91f92de43 (patch) | |
| tree | 5971cd5ec435ca750b8ba77929df53e1fd78dbad /drivers/scsi/sr.h | |
| parent | 57a6fa9acd6b4a479a6ede4d6d2258f04afd3a6f (diff) | |
| download | linux-79b9677d885d1a792bc103f2febb06f91f92de43.tar.xz | |
[SCSI] sr: check_events() ignore GET_EVENT when TUR says otherwise
Some broken devices indicates that media has changed on every
GET_EVENT_STATUS_NOTIFICATION. This translates into MEDIA_CHANGE
uevent on every open() which lets udev run into a loop.
Verify GET_EVENT result against TUR and if it generates spurious
events for several times in a row, ignore the GET_EVENT events, and
trust only the TUR status.
This is the log of a USB stick with a (broken) fake CDROM drive:
scsi 5:0:0:0: Direct-Access SanDisk U3 Cruzer Micro 8.02 PQ: 0 ANSI: 0 CCS
sd 5:0:0:0: Attached scsi generic sg3 type 0
scsi 5:0:0:1: CD-ROM SanDisk U3 Cruzer Micro 8.02 PQ: 0 ANSI: 0
sd 5:0:0:0: [sdb] Attached SCSI removable disk
sr2: scsi3-mmc drive: 48x/48x tray
sr 5:0:0:1: Attached scsi CD-ROM sr2
sr 5:0:0:1: Attached scsi generic sg4 type 5
sr2: GET_EVENT and TUR disagree continuously, suppress GET_EVENT events
sd 5:0:0:0: [sdb] 31777279 512-byte logical blocks: (16.2 GB/15.1 GiB)
sd 5:0:0:0: [sdb] No Caching mode page present
sd 5:0:0:0: [sdb] Assuming drive cache: write through
sd 5:0:0:0: [sdb] No Caching mode page present
sd 5:0:0:0: [sdb] Assuming drive cache: write through
sdb: sdb1
-tj: Updated to consider only spurious GET_EVENT events among
different types of disagreement and allow using TUR for kernel
event polling after GET_EVENT is ignored.
Reported-By: Markus Rathgeb maggu2810@googlemail.com
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: stable@kernel.org # >= v2.6.38, fixes udev busy looping w/ certain devices
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Diffstat (limited to 'drivers/scsi/sr.h')
| -rw-r--r-- | drivers/scsi/sr.h | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/drivers/scsi/sr.h b/drivers/scsi/sr.h index e036f1dc83c8..37c8f6b17510 100644 --- a/drivers/scsi/sr.h +++ b/drivers/scsi/sr.h @@ -41,6 +41,13 @@ typedef struct scsi_cd { unsigned readcd_known:1; /* drive supports READ_CD (0xbe) */ unsigned readcd_cdda:1; /* reading audio data using READ_CD */ unsigned media_present:1; /* media is present */ + + /* GET_EVENT spurious event handling, blk layer guarantees exclusion */ + int tur_mismatch; /* nr of get_event TUR mismatches */ + bool tur_changed:1; /* changed according to TUR */ + bool get_event_changed:1; /* changed according to GET_EVENT */ + bool ignore_get_event:1; /* GET_EVENT is unreliable, use TUR */ + struct cdrom_device_info cdi; /* We hold gendisk and scsi_device references on probe and use * the refs on this kref to decide when to release them */ |