[dm-devel] Re: [PATCH resubmit] do_mount: reduce stack consumption

[Heiko Carstens]

> > Ok, I'll dust it off, make sure it seems to work (at the time I first
> > wrote it, I think it caused 'md' to deadlock) and submit it.
> > 
> > NeilBrown
> > 
> 
> For your consideration and testing (it works for me, but I'd like to
> see it tested a bit more heavily in a variety of configurations).

Works fine for me. Thank you!

However I noticed another recursive call while dumping all call traces:
 ...
 [<00000000001e1952>] zfcp_scsi_command_async+0xf6/0x1c4
 [<000000000013cd6a>] scsi_dispatch_cmd+0x1ae/0x37c
 [<0000000000143dc4>] scsi_request_fn+0x1dc/0x390
 [<000000000012f65a>] generic_unplug_device+0x2a/0x38
 [<0000000000181262>] dm_table_unplug_all+0x42/0x58
 [<000000000017e598>] dm_unplug_all+0x2c/0x44
 [<0000000000181262>] dm_table_unplug_all+0x42/0x58
 [<000000000017e598>] dm_unplug_all+0x2c/0x44
 [<00000000000782aa>] block_sync_page+0x4e/0x68
 [<00000000000514f8>] sync_page+0x48/0x68
 [<00000000002ab36e>] __wait_on_bit+0x9a/0xe0
 ...

Even though there is a lot of space left on the stack (this time) I don't
think it's desirable to have recursive calls. Especially not when going
for 4k stacks.

Heiko