dm io: fix panic on large request
authorMilan Broz <mbroz@redhat.com>
Sat, 21 Jul 2007 11:37:27 +0000 (04:37 -0700)
committerLinus Torvalds <torvalds@woody.linux-foundation.org>
Sun, 22 Jul 2007 00:49:14 +0000 (17:49 -0700)
Flush workqueue before releasing bioset and mopools in dm-crypt.  There can
be finished but not yet released request.

Call chain causing oops:
  run workqueue
    dec_pending
      bio_endio(...);
       <remove device request - remove mempool>
      mempool_free(io, cc->io_pool);

This usually happens when cryptsetup create temporary
luks mapping in the beggining of crypt device activation.

When dm-core calls destructor crypt_dtr, no new request
are possible.

Signed-off-by: Milan Broz <mbroz@redhat.com>
Cc: Chuck Ebbert <cebbert@redhat.com>
Cc: Patrick McHardy <kaber@trash.net>
Acked-by: Alasdair G Kergon <agk@redhat.com>
Cc: Christophe Saout <christophe@saout.de>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
drivers/md/dm-crypt.c

index ba952a032598c2411bb3f7ff793f6d00baec92bc..bdc52d6922b7d998f27068cce53ededb302f0b09 100644 (file)
@@ -920,6 +920,8 @@ static void crypt_dtr(struct dm_target *ti)
 {
        struct crypt_config *cc = (struct crypt_config *) ti->private;
 
+       flush_workqueue(_kcryptd_workqueue);
+
        bioset_free(cc->bs);
        mempool_destroy(cc->page_pool);
        mempool_destroy(cc->io_pool);