On Tue, Jul 07 2015 at 9:47am -0400, Jens Axboe <axboe@xxxxxxxxx> wrote: > On 07/01/2015 10:57 AM, Mike Snitzer wrote: > >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 <snitzer@xxxxxxxxxx> > >Cc: stable@xxxxxxxxxxxxxxx > >--- > > block/bio-integrity.c | 4 ++-- > > 1 file changed, 2 insertions(+), 2 deletions(-) > > Applied for this series. Awesome, thanks. -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
