On Wed, Nov 9, 2016 at 11:09 AM, Dan Williams <dan.j.williams@xxxxxxxxx> wrote:
On Wed, Nov 9, 2016 at 9:36 AM, John Garry <john.garry@xxxxxxxxxx> wrote:
On 09/11/2016 12:28, John Garry wrote:
On 03/11/2016 14:58, John Garry wrote:
The following patch introduces an annoying WARN
when a device is removed from the SAS topology:
[SCSI] libsas: prevent domain rediscovery competing with ata error
handling
Are there any views on this patch? I would have thought that the parties
who use the drivers based on libsas would be interested in fixing this
bug.
I should have added the before and after logs earlier, so the issue is
illustrated. Now attached. When a 24-port expander is unplugged we get >6k
lines of WARN on the console, lasting >30 seconds. Not nice.
I might be mistaken, but this patch seems functionally identical to
this attempt:
http://marc.info/?l=linux-scsi&m=143459794823595&w=2
i.e. it moves the port destruction to the workqueue and still suffers
from the flutter problem:
http://marc.info/?l=linux-scsi&m=143801026028006&w=2
http://marc.info/?l=linux-scsi&m=143801971131073&w=2
Perhaps we instead need to quiet this warning?
http://marc.info/?l=linux-scsi&m=143802229932175&w=2
Alternatively we need a mechanism to cancel in-flight port shutdown
requests when we start re-attaching devices before queued port
destruction events have run.
.