[PATCH] don't do exit_io_context() until we know we won't be doing any IO
Al Viro authored

testcase:

mount /dev/sdb10 /mnt
touch /mnt/tmp/b
umount /mnt
mount /dev/sdb10 /mnt
rm /mnt/tmp/b </mnt/tmp/b
umount /mnt

and watch blkdev_ioc line in /proc/slabinfo.  Vanilla kernel leaks.
Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
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