scsi: introduce a quirk for false cache reporting
Some SATA to USB bridges fail to cooperate with some
drives resulting in no cache being present being reported
to the host. That causes the host to skip sending
a command to synchronize caches. That causes data loss
when the drive is powered down.
Signed-off-by: Oliver Neukum <oneukum@suse.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index a4f4d69..edb7d5d 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -4238,6 +4238,8 @@
u = IGNORE_UAS (don't bind to the uas driver);
w = NO_WP_DETECT (don't test whether the
medium is write-protected).
+ y = ALWAYS_SYNC (issue a SYNCHRONIZE_CACHE
+ even if the device claims no cache)
Example: quirks=0419:aaf5:rl,0421:0433:rc
user_debug= [KNL,ARM]