Hi! As part of my regression tracking work I noticed this bug report that was filed about a week ago: https://bugzilla.kernel.org/show_bug.cgi?id=215647 To quote the first para: > there is a bug in the aoe driver module between v4.20-rc1 and > v5.14-rc1 inroduced in 3582dd2 (aoe: convert aoeblk to blk-mq) and > fixed in 6560ec9 (aoe: use blk_mq_alloc_disk and blk_cleanup_disk). > Every forcible removal of an aoe device (eg. "rmmod aoe" with aoe > devices available or "aoe-flush ex.x") leads to a page fault. This > bug was successfully reproduced with kernel 5.10.92 from the debian > repository, there were no changes to the affected code between > v4.20-rc1 and v5.14-rc1. Version 4.19.208 (from debian buster) and > 5.17-rc4 (from debian experimental) are confirmed not to be > affected. I checked the logs to see why mainline might not be affected anymore and noticed a recent commit in the same area: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/drivers/block/aoe/aoedev.c?id=6560ec961a080944f8d5e1fef17b771bfaf189cb > From 6560ec961a080944f8d5e1fef17b771bfaf189cb Mon Sep 17 00:00:00 2001 > From: Christoph Hellwig <hch@xxxxxx> > Date: Wed, 2 Jun 2021 09:53:31 +0300 > Subject: aoe: use blk_mq_alloc_disk and blk_cleanup_disk > > Use blk_mq_alloc_disk and blk_cleanup_disk to simplify the gendisk and > request_queue allocation. > > Signed-off-by: Christoph Hellwig <hch@xxxxxx> > Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@xxxxxxx> > Link: https://lore.kernel.org/r/20210602065345.355274-17-hch@xxxxxx > Signed-off-by: Jens Axboe <axboe@xxxxxxxxx> > --- > drivers/block/aoe/aoedev.c | 3 +-- > 1 file changed, 1 insertion(+), 2 deletions(-) > > (limited to 'drivers/block/aoe/aoedev.c') > > diff --git a/drivers/block/aoe/aoedev.c b/drivers/block/aoe/aoedev.c > index e2ea2356da061..c5753c6bfe804 100644 > --- a/drivers/block/aoe/aoedev.c > +++ b/drivers/block/aoe/aoedev.c > @@ -277,9 +277,8 @@ freedev(struct aoedev *d) > if (d->gd) { > aoedisk_rm_debugfs(d); > del_gendisk(d->gd); > - put_disk(d->gd); > + blk_cleanup_disk(d->gd); > blk_mq_free_tag_set(&d->tag_set); > - blk_cleanup_queue(d->blkq); > } > t = d->targets; > e = t + d->ntargets; Does that need backporting? Or is the patch the reporter provided in bugzilla the easier and safer way to fix that regression in older releases? Ciao, Thorsten
