From 1501efadc524a0c99494b576923091589a52d2a4 Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Wed, 13 Jan 2016 16:00:07 -0800 Subject: md/raid: only permit hot-add of compatible integrity profiles It is not safe for an integrity profile to be changed while i/o is in-flight in the queue. Prevent adding new disks or otherwise online spares to an array if the device has an incompatible integrity profile. The original change to the blk_integrity_unregister implementation in md, commmit c7bfced9a671 "md: suspend i/o during runtime blk_integrity_unregister" introduced an immediate hang regression. This policy of disallowing changes the integrity profile once one has been established is shared with DM. Here is an abbreviated log from a test run that: 1/ Creates a degraded raid1 with an integrity-enabled device (pmem0s) [ 59.076127] 2/ Tries to add an integrity-disabled device (pmem1m) [ 90.489209] 3/ Retries with an integrity-enabled device (pmem1s) [ 205.671277] [ 59.076127] md/raid1:md0: active with 1 out of 2 mirrors [ 59.078302] md: data integrity enabled on md0 [..] [ 90.489209] md0: incompatible integrity profile for pmem1m [..] [ 205.671277] md: super_written gets error=-5 [ 205.677386] md/raid1:md0: Disk failure on pmem1m, disabling device. [ 205.677386] md/raid1:md0: Operation continuing on 1 devices. [ 205.683037] RAID1 conf printout: [ 205.684699] --- wd:1 rd:2 [ 205.685972] disk 0, wo:0, o:1, dev:pmem0s [ 205.687562] disk 1, wo:1, o:1, dev:pmem1s [ 205.691717] md: recovery of RAID array md0 Fixes: c7bfced9a671 ("md: suspend i/o during runtime blk_integrity_unregister") Cc: Cc: Mike Snitzer Reported-by: NeilBrown Signed-off-by: Dan Williams Signed-off-by: NeilBrown --- drivers/md/multipath.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'drivers/md/multipath.c') diff --git a/drivers/md/multipath.c b/drivers/md/multipath.c index 7331a80d89f1..0a72ab6e6c20 100644 --- a/drivers/md/multipath.c +++ b/drivers/md/multipath.c @@ -257,6 +257,9 @@ static int multipath_add_disk(struct mddev *mddev, struct md_rdev *rdev) disk_stack_limits(mddev->gendisk, rdev->bdev, rdev->data_offset << 9); + err = md_integrity_add_rdev(rdev, mddev); + if (err) + break; spin_lock_irq(&conf->device_lock); mddev->degraded--; rdev->raid_disk = path; @@ -264,9 +267,6 @@ static int multipath_add_disk(struct mddev *mddev, struct md_rdev *rdev) spin_unlock_irq(&conf->device_lock); rcu_assign_pointer(p->rdev, rdev); err = 0; - mddev_suspend(mddev); - md_integrity_add_rdev(rdev, mddev); - mddev_resume(mddev); break; } -- cgit v1.2.3