On 7/22/19 1:39 PM, Ming Lei wrote: > Hi, > > blk-mq may schedule to call queue's complete function on remote CPU via > IPI, but never provide any way to synchronize the request's complete > fn. > > In some driver's EH(such as NVMe), hardware queue's resource may be freed & > re-allocated. If the completed request's complete fn is run finally after the > hardware queue's resource is released, kernel crash will be triggered. > Have you seen the crash? Anyway to emulate/verify this bug.. > Fixes this issue by waitting until completed req's complete fn is run. > > Thanks, > Ming > > Ming Lei (5): > blk-mq: introduce blk_mq_request_completed() > blk-mq: introduce blk_mq_tagset_wait_completed_request() > nvme: don't abort completed request in nvme_cancel_request > nvme: wait until all completed request's complete fn is called > blk-mq: remove blk_mq_complete_request_sync > > block/blk-mq-tag.c | 32 ++++++++++++++++++++++++++++++++ > block/blk-mq.c | 13 ++++++------- > drivers/nvme/host/core.c | 6 +++++- > drivers/nvme/host/pci.c | 2 ++ > drivers/nvme/host/rdma.c | 8 ++++++-- > drivers/nvme/host/tcp.c | 8 ++++++-- > drivers/nvme/target/loop.c | 2 ++ > include/linux/blk-mq.h | 3 ++- > 8 files changed, 61 insertions(+), 13 deletions(-) > > Cc: Max Gurtovoy <maxg@xxxxxxxxxxxx> > Cc: Sagi Grimberg <sagi@xxxxxxxxxxx> > Cc: Keith Busch <keith.busch@xxxxxxxxx> > Cc: Christoph Hellwig <hch@xxxxxx> >
