On 06/21/2016 06:24 AM, Anand Jain wrote:
From: Anand Jain <[email protected]>Further to the commit bc178622d40d87e75abc131007342429c9b03351 btrfs: use rcu_barrier() to wait for bdev puts at unmount This patch implements a method to time wait on the __free_device() which actually does the bdev put. This is needed as the user space running 'btrfs fi show -d' immediately after the replace and unmount, is still reading older information from the device.
Thanks for working on this Anand. Since it looks like blkdev_put can deadlock against us, can we please switch to making sure we fully flush the outstanding IO? It's probably enough to do a sync_blockdev() call before we allow the unmount to finish, but we can toss in an invalidate_bdev for good measure.
Then we can get rid of the mdelay loop completely, which seems pretty error prone to me.
Thanks! -chris -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
