I think we should cherry-pick 41e3efd07d5a02c80f503e29d755aa1bbb4245de https://lore.kernel.org/patchwork/patch/856512/ into 4.14. It fixes a potential resource leak when shutting down the request queue. Once this patch is applied, there is a potential for a null pointer dereference. That's what the second patch fixes. The third patch is just an optimization to stop processing earlier. See https://patchwork.kernel.org/patch/10925469/ for the initial motivation. This commit applies to v4.14.116. It is already included in 4.19. 4.19 doesn't suffer from the null pointer dereference because later commits migrate the mmc stack to blk-mq. I tested this patch set by randomly connecting/disconnecting the SD card. I got over 189650 itarations without a problem. Thanks, Raul Adrian Hunter (1): mmc: block: Simplify cleaning up the queue Raul E Rangel (2): mmc: Fix null pointer dereference in mmc_init_request mmc: Kill the request if the queuedata has been removed drivers/mmc/core/block.c | 17 ++++++++++++----- drivers/mmc/core/queue.c | 14 +++++++++++--- 2 files changed, 23 insertions(+), 8 deletions(-) -- 2.21.0.1020.gf2820cf01a-goog
