From bb8bd38b9a1685334b73e8c62e128cbedb875867 Mon Sep 17 00:00:00 2001 From: Mike Snitzer Date: Wed, 1 Jul 2015 12:57:40 -0400 Subject: [PATCH] bio integrity: do not assume bio_integrity_pool exists if bioset exists bio_integrity_alloc() and bio_integrity_free() assume that if a bio was allocated from a bioset that that bioset also had its bio_integrity_pool allocated using bioset_integrity_create(). This is a very bad assumption given that bioset_create() and bioset_integrity_create() are completely disjoint. Not all callers of bioset_create() have been trained to also call bioset_integrity_create() -- and they may not care to be. Fix this by falling back to kmalloc'ing 'struct bio_integrity_payload' rather than force all bioset consumers to (wastefully) preallocate a bio_integrity_pool that they very likely won't actually need (given the niche nature of the current block integrity support). Otherwise, a NULL pointer "Kernel BUG" with a trace like the following will be observed (as seen on s390x using zfcp storage) because dm-io doesn't use bioset_integrity_create() when creating its bioset: [ 791.643338] Call Trace: [ 791.643339] ([<00000003df98b848>] 0x3df98b848) [ 791.643341] [<00000000002c5de8>] bio_integrity_alloc+0x48/0xf8 [ 791.643348] [<00000000002c6486>] bio_integrity_prep+0xae/0x2f0 [ 791.643349] [<0000000000371e38>] blk_queue_bio+0x1c8/0x3d8 [ 791.643355] [<000000000036f8d0>] generic_make_request+0xc0/0x100 [ 791.643357] [<000000000036f9b2>] submit_bio+0xa2/0x198 [ 791.643406] [<000003ff801f9774>] dispatch_io+0x15c/0x3b0 [dm_mod] [ 791.643419] [<000003ff801f9b3e>] dm_io+0x176/0x2f0 [dm_mod] [ 791.643423] [<000003ff8074b28a>] do_reads+0x13a/0x1a8 [dm_mirror] [ 791.643425] [<000003ff8074b43a>] do_mirror+0x142/0x298 [dm_mirror] [ 791.643428] [<0000000000154fca>] process_one_work+0x18a/0x3f8 [ 791.643432] [<000000000015598a>] worker_thread+0x132/0x3b0 [ 791.643435] [<000000000015d49a>] kthread+0xd2/0xd8 [ 791.643438] [<00000000005bc0ca>] kernel_thread_starter+0x6/0xc [ 791.643446] [<00000000005bc0c4>] kernel_thread_starter+0x0/0xc Signed-off-by: Mike Snitzer Cc: stable@vger.kernel.org Signed-off-by: Jens Axboe --- block/bio-integrity.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/block/bio-integrity.c b/block/bio-integrity.c index 0436c21db7f2..719b7152aed1 100644 --- a/block/bio-integrity.c +++ b/block/bio-integrity.c @@ -51,7 +51,7 @@ struct bio_integrity_payload *bio_integrity_alloc(struct bio *bio, unsigned long idx = BIO_POOL_NONE; unsigned inline_vecs; - if (!bs) { + if (!bs || !bs->bio_integrity_pool) { bip = kmalloc(sizeof(struct bio_integrity_payload) + sizeof(struct bio_vec) * nr_vecs, gfp_mask); inline_vecs = nr_vecs; @@ -104,7 +104,7 @@ void bio_integrity_free(struct bio *bio) kfree(page_address(bip->bip_vec->bv_page) + bip->bip_vec->bv_offset); - if (bs) { + if (bs && bs->bio_integrity_pool) { if (bip->bip_slab != BIO_POOL_NONE) bvec_free(bs->bvec_integrity_pool, bip->bip_vec, bip->bip_slab);