[dm-devel] Deadlock when using crypto API for block devices
herbert at gondor.apana.org.au
Fri Aug 24 13:21:45 UTC 2018
On Fri, Aug 24, 2018 at 09:00:00AM -0400, Mikulas Patocka wrote:
> BTW. gcmaes_crypt_by_sg also contains GFP_ATOMIC and -ENOMEM, behind a
> pretty complex condition. Do you mean that this condition is part of the
> contract that the crypto API provides?
This is an implementation defect. I think for this case we should
fall back to software GCM if the accelerated version fails.
> Should "req->src->offset + req->src->length < PAGE_SIZE" use "<=" instead?
> Because if the data ends up at page boundary, it will use the atomic
> allocation that can fail.
This condition does look strange. It's introduced by the commit
e845520707f85c539ce04bb73c6070e9441480be. Dave, what exactly is
it meant to do?
Email: Herbert Xu <herbert at gondor.apana.org.au>
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