SRU request for LP#238118

Stefan Bader stefan.bader at
Wed Jun 11 21:25:10 UTC 2008

SRU justification:

Impact: Hard lockups when doing heavy (IMO just higher) I/O load. The
reason is that dma_get_required_mask returns a wrong value and thus the
memory management will get confused.
(Bit of a guess but adapter will use 32bit DMA mask instead of 39bit
which it should use. So probably memory areas won't be used and other
areas not freed because there are still free ones)

Fix: From upstream (in Intrepid) will remove the limit to the current
dma mask when actually the new limit is required.

Testcase: From kernel bug report it was sufficient to do a gzip which
hung within a few minutes.

Note: this change would also apply to Gutsy. Should changes go to both?
Not really a security issue...
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