From: Milan Broz The pending reference count must be incremented *before* the async work is queued to another thread, not after. Otherwise there's a race if the work completes and decrements the reference count before it gets incremented. Signed-off-by: Milan Broz Signed-off-by: Alasdair G Kergon --- drivers/md/dm-crypt.c | 5 ++--- 1 files changed, 2 insertions(+), 3 deletions(-) Index: linux-2.6.27-rc7/drivers/md/dm-crypt.c =================================================================== --- linux-2.6.27-rc7.orig/drivers/md/dm-crypt.c 2008-09-23 15:11:45.000000000 +0100 +++ linux-2.6.27-rc7/drivers/md/dm-crypt.c 2008-09-23 15:11:46.000000000 +0100 @@ -719,16 +719,15 @@ static void kcryptd_crypt_write_convert( remaining -= clone->bi_size; + crypt_inc_pending(io); r = crypt_convert(cc, &io->ctx); if (atomic_dec_and_test(&io->ctx.pending)) { /* processed, no running async crypto */ - crypt_inc_pending(io); kcryptd_crypt_write_io_submit(io, r, 0); if (unlikely(r < 0)) break; - } else - crypt_inc_pending(io); + } /* out of memory -> run queues */ if (unlikely(remaining)) {