[PATCH] blacklist device don't use SYNCHRONIZE_CACHE

[PATCH] blacklist device don't use SYNCHRONIZE_CACHE

[Michael Clark]

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Hi all,

With qla2300 loaded (and sdc a LUN on an external FC RAID controller),
I was getting a hang on reboot at:

   Synchronizing SCSI cache for disk sdc:

I did some debugging by changing the timeout in sd_sync_cache and
found the RAID Controller was just dropping the commands (it's an
external battery backed RAID array so the sd_sync_cache is not
important anyway).

So, attached patch adds to the SCSI blacklist infrastructure to
allow listing devices for which we shouldn't send a SYNCRONIZE_CACHE
command and adds in the misbehaving device i have here.

Now I can reboot ;) without waiting 7.5 minutes.

BTW - The default of 15 retries of 30 secs each is insane
(3 in sd_sync_cache x 5 in scsi_wait_req) - any real need
for the additional outer loop in sd_sync_cache ?

~mc


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Re: [PATCH] blacklist device don't use SYNCHRONIZE_CACHE

[Michael Clark]

Apologies for base64 attachment - if anyone can tell me how
to stop my Debian Mozilla 1.7 from randomly deciding to base64
my attached patches (it only decides to do it on some of them).

~mc

On 10/29/04 17:00, Michael Clark wrote:
> Hi all,
> 
> With qla2300 loaded (and sdc a LUN on an external FC RAID controller),
> I was getting a hang on reboot at:
> 
>   Synchronizing SCSI cache for disk sdc:
> 
> I did some debugging by changing the timeout in sd_sync_cache and
> found the RAID Controller was just dropping the commands (it's an
> external battery backed RAID array so the sd_sync_cache is not
> important anyway).
> 
> So, attached patch adds to the SCSI blacklist infrastructure to
> allow listing devices for which we shouldn't send a SYNCRONIZE_CACHE
> command and adds in the misbehaving device i have here.
> 
> Now I can reboot ;) without waiting 7.5 minutes.
> 
> BTW - The default of 15 retries of 30 secs each is insane
> (3 in sd_sync_cache x 5 in scsi_wait_req) - any real need
> for the additional outer loop in sd_sync_cache ?
> 
> ~mc