This is a note to let you know that I've just added the patch titled md/raid: only permit hot-add of compatible integrity profiles to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: md-raid-only-permit-hot-add-of-compatible-integrity-profiles.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 1501efadc524a0c99494b576923091589a52d2a4 Mon Sep 17 00:00:00 2001 From: Dan Williams <dan.j.williams@xxxxxxxxx> Date: Wed, 13 Jan 2016 16:00:07 -0800 Subject: md/raid: only permit hot-add of compatible integrity profiles From: Dan Williams <dan.j.williams@xxxxxxxxx> commit 1501efadc524a0c99494b576923091589a52d2a4 upstream. 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: Mike Snitzer <snitzer@xxxxxxxxxx> Reported-by: NeilBrown <neilb@xxxxxxxx> Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx> Signed-off-by: NeilBrown <neilb@xxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/md/md.c | 28 ++++++++++++++++------------ drivers/md/md.h | 2 +- drivers/md/multipath.c | 6 +++--- drivers/md/raid1.c | 6 +++--- drivers/md/raid10.c | 6 +++--- 5 files changed, 26 insertions(+), 22 deletions(-) --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -2017,28 +2017,32 @@ int md_integrity_register(struct mddev * } EXPORT_SYMBOL(md_integrity_register); -/* Disable data integrity if non-capable/non-matching disk is being added */ -void md_integrity_add_rdev(struct md_rdev *rdev, struct mddev *mddev) +/* + * Attempt to add an rdev, but only if it is consistent with the current + * integrity profile + */ +int md_integrity_add_rdev(struct md_rdev *rdev, struct mddev *mddev) { struct blk_integrity *bi_rdev; struct blk_integrity *bi_mddev; + char name[BDEVNAME_SIZE]; if (!mddev->gendisk) - return; + return 0; bi_rdev = bdev_get_integrity(rdev->bdev); bi_mddev = blk_get_integrity(mddev->gendisk); if (!bi_mddev) /* nothing to do */ - return; - if (rdev->raid_disk < 0) /* skip spares */ - return; - if (bi_rdev && blk_integrity_compare(mddev->gendisk, - rdev->bdev->bd_disk) >= 0) - return; - WARN_ON_ONCE(!mddev->suspended); - printk(KERN_NOTICE "disabling data integrity on %s\n", mdname(mddev)); - blk_integrity_unregister(mddev->gendisk); + return 0; + + if (blk_integrity_compare(mddev->gendisk, rdev->bdev->bd_disk) != 0) { + printk(KERN_NOTICE "%s: incompatible integrity profile for %s\n", + mdname(mddev), bdevname(rdev->bdev, name)); + return -ENXIO; + } + + return 0; } EXPORT_SYMBOL(md_integrity_add_rdev); --- a/drivers/md/md.h +++ b/drivers/md/md.h @@ -657,7 +657,7 @@ extern void md_wait_for_blocked_rdev(str extern void md_set_array_sectors(struct mddev *mddev, sector_t array_sectors); extern int md_check_no_bitmap(struct mddev *mddev); extern int md_integrity_register(struct mddev *mddev); -extern void md_integrity_add_rdev(struct md_rdev *rdev, struct mddev *mddev); +extern int md_integrity_add_rdev(struct md_rdev *rdev, struct mddev *mddev); extern int strict_strtoul_scaled(const char *cp, unsigned long *res, int scale); extern void mddev_init(struct mddev *mddev); --- a/drivers/md/multipath.c +++ b/drivers/md/multipath.c @@ -257,6 +257,9 @@ static int multipath_add_disk(struct mdd 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 mdd 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; } --- a/drivers/md/raid1.c +++ b/drivers/md/raid1.c @@ -1589,6 +1589,9 @@ static int raid1_add_disk(struct mddev * if (mddev->recovery_disabled == conf->recovery_disabled) return -EBUSY; + if (md_integrity_add_rdev(rdev, mddev)) + return -ENXIO; + if (rdev->raid_disk >= 0) first = last = rdev->raid_disk; @@ -1632,9 +1635,6 @@ static int raid1_add_disk(struct mddev * break; } } - mddev_suspend(mddev); - md_integrity_add_rdev(rdev, mddev); - mddev_resume(mddev); if (mddev->queue && blk_queue_discard(bdev_get_queue(rdev->bdev))) queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, mddev->queue); print_conf(conf); --- a/drivers/md/raid10.c +++ b/drivers/md/raid10.c @@ -1698,6 +1698,9 @@ static int raid10_add_disk(struct mddev if (rdev->saved_raid_disk < 0 && !_enough(conf, 1, -1)) return -EINVAL; + if (md_integrity_add_rdev(rdev, mddev)) + return -ENXIO; + if (rdev->raid_disk >= 0) first = last = rdev->raid_disk; @@ -1739,9 +1742,6 @@ static int raid10_add_disk(struct mddev rcu_assign_pointer(p->rdev, rdev); break; } - mddev_suspend(mddev); - md_integrity_add_rdev(rdev, mddev); - mddev_resume(mddev); if (mddev->queue && blk_queue_discard(bdev_get_queue(rdev->bdev))) queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, mddev->queue); Patches currently in stable-queue which might be from dan.j.williams@xxxxxxxxx are queue-4.4/md-raid-only-permit-hot-add-of-compatible-integrity-profiles.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html