swh:1:snp:38ae39f9fd01a4b0ef06fab5668b65bf4c2aca03
Revision 5044eed48886b105a123333fe7ca97c6bd496120 authored by Jens Axboe on 25 April 2007, 09:53:48 UTC, committed by Linus Torvalds on 25 April 2007, 15:41:48 UTC
There's a really rare and obscure bug in CFQ, that causes a crash in cfq_dispatch_insert() due to rq == NULL. One example of the resulting oops is seen here: http://lkml.org/lkml/2007/4/15/41 Neil correctly diagnosed the situation for how this can happen: if two concurrent requests with the exact same sector number (due to direct IO or aliasing between MD and the raw device access), the alias handling will add the request to the sortlist, but next_rq remains NULL. Read the more complete analysis at: http://lkml.org/lkml/2007/4/25/57 This looks like it requires md to trigger, even though it should potentially be possible to due with O_DIRECT (at least if you edit the kernel and doctor some of the unplug calls). The fix is to move the ->next_rq update to when we add a request to the rbtree. Then we remove the possibility for a request to exist in the rbtree code, but not have ->next_rq correctly updated. Signed-off-by: Jens Axboe <jens.axboe@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Tip revision: 0cdd776ec92c0fec768c7079331804d3e52d4b27 authored by Linus Torvalds on 15 May 2022, 15:08:51 UTC
Merge tag 'driver-core-5.18-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Merge tag 'driver-core-5.18-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Tip revision: 0cdd776
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arch | ||
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crypto | ||
drivers | ||
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include | ||
init | ||
ipc | ||
kernel | ||
lib | ||
mm | ||
net | ||
scripts | ||
security | ||
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.gitignore | -rw-r--r-- | 572 bytes |
.mailmap | -rw-r--r-- | 3.6 KB |
COPYING | -rw-r--r-- | 18.3 KB |
CREDITS | -rw-r--r-- | 88.9 KB |
Kbuild | -rw-r--r-- | 1.2 KB |
MAINTAINERS | -rw-r--r-- | 82.2 KB |
Makefile | -rw-r--r-- | 49.1 KB |
README | -rw-r--r-- | 16.5 KB |
REPORTING-BUGS | -rw-r--r-- | 3.0 KB |
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