On Sat, 17 May 2008, Alistair John Strachan wrote:
Ahh, yeah, I hate how all the distro's hide the default messages. Bad,
bad.
Ok, looks like block device breakage, possibly MD-related.
Looks like something is waiting for IO to complete, and it never does.
Which indicates the block layer. And yes, likely some race in unplugging.
And while it is waiting, it is holding the XFS locks, because this was
brought on by a low-memory situation:
And as a result, all the XFS stuff is then waiting for that lock which is
held by pdflush above:
Jens, there's been a *lot* of breakage in the block layer. The DMA bounce
buffer crap, and this looks like the atomic bit setting was broken too.
Alistair, does the problem go away if you revert both the patch from Neil
and the original patch that caused the need for that patch to begin with
(ie commit 75ad23bc0fcb4f992a5d06982bf0857ab1738e9e "block: make queue
flags non-atomic").
Jens, Nick, I think that whole series just needs to be undone.
Linus
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