Re: [PATCH] sd name space exhaustion causes system hang

[Michael Reed <mdr@sgi.com>]

On 09/21/2010 10:08 AM, Hannes Reinecke wrote:
> Michael Reed wrote:
>> Following a site power outage which re-enabled all the ports on my FC
>> switches, my system subsequently booted with far too many luns!  I had
>> let it run hoping it would make multi-user.  It didn't.  :(  It hung solid
>> after exhausting the last sd device, sdzzz, and attempting to create sdaaaa
>> and beyond.  I was unable to get a dump.
>>
>> Discovered using a 2.6.32.13 based system.
>>
>> Patch at the bottom corrects this by detecting when the last index is
>> utilized and failing the sd probe of the device.  Patch applies to
>> scsi-misc-2.6.
>>
> Hmm. Shouldn't we rather use dynamic majors once we're over
> SD_MAJORS? We do have enough space in the 'index' field and the name
> is generated dynamically anyway ...

A bit beyond the scope of what I was trying to correct.  And beyond my
current knowledge of how things work.  If you'd care to guide me, or
provide me a patch for testing....  I can probably get my config up to
30,000 or so luns.

Mike

> 
> Cheers,
> 
> Hannes