Brian Behlendorf 65d56083b4 Fix zpool on zvol lock inversion deadlock ... In all but one case the spa_namespace_lock is taken before the bdev->bd_mutex lock. But Linux __blkdev_get() function calls fops->open() with the bdev->bd_mutex lock held and we must somehow still safely acquire the spa_namespace_lock. To avoid a potential lock inversion deadlock we preemptively try to take the spa_namespace_lock(). Normally it will not be contended and this is safe because spa_open_common() handles the case where the caller already holds the spa_namespace_lock. When it is contended we risk a lock inversion if we were to block waiting for the lock. Luckily, the __blkdev_get() function allows us to return -ERESTARTSYS which will result in bdev->bd_mutex being dropped, reacquired, and fops->open() being called again. This process can be repeated safely until both locks are acquired. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Jorgen Lundman <lundman@lundman.net> Closes #612		2012-12-20 09:57:39 -08:00
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avl	Add script for builtin module building.	2012-07-26 13:45:09 -07:00
nvpair	Add script for builtin module building.	2012-07-26 13:45:09 -07:00
unicode	Add script for builtin module building.	2012-07-26 13:45:09 -07:00
zcommon	Illumos #1948: zpool list should show more detailed pool info	2012-09-19 13:39:05 -07:00
zfs	Fix zpool on zvol lock inversion deadlock	2012-12-20 09:57:39 -08:00
zpios	Add script for builtin module building.	2012-07-26 13:45:09 -07:00
.gitignore	Add .gitignore files to exclude build products	2010-01-08 11:35:17 -08:00
Makefile.in	Add script for builtin module building.	2012-07-26 13:45:09 -07:00