From 3a574919f0cc15a46ec14c3e5e08300908991915 Mon Sep 17 00:00:00 2001 From: Ulf Hansson Date: Tue, 27 Feb 2018 11:49:09 +0100 Subject: mmc: core: Avoid hanging to claim host for mmc via some nested calls As the block layer, since the conversion to blkmq, claims the host using a context, a following nested call to mmc_claim_host(), which isn't using a context, may hang. Calling mmc_interrupt_hpi() and mmc_read_bkops_status() via the mmc block layer, may suffer from this problem, as these functions are calling mmc_claim|release_host(). Let's fix the problem by removing the calls to mmc_claim|release_host() from the above mentioned functions and instead make the callers responsible of claiming/releasing the host. As a matter of fact, the existing callers already deals with it. Fixes: 81196976ed94 ("mmc: block: Add blk-mq support") Reported-by: Dmitry Osipenko Suggested-by: Adrian Hunter Tested-by: Dmitry Osipenko Signed-off-by: Ulf Hansson Acked-by: Adrian Hunter Reviewed-by: Shawn Lin --- drivers/mmc/core/mmc_ops.c | 4 ---- 1 file changed, 4 deletions(-) diff --git a/drivers/mmc/core/mmc_ops.c b/drivers/mmc/core/mmc_ops.c index 908e4db03535..42d6aa89a48a 100644 --- a/drivers/mmc/core/mmc_ops.c +++ b/drivers/mmc/core/mmc_ops.c @@ -848,7 +848,6 @@ int mmc_interrupt_hpi(struct mmc_card *card) return 1; } - mmc_claim_host(card->host); err = mmc_send_status(card, &status); if (err) { pr_err("%s: Get card status fail\n", mmc_hostname(card->host)); @@ -890,7 +889,6 @@ int mmc_interrupt_hpi(struct mmc_card *card) } while (!err); out: - mmc_release_host(card->host); return err; } @@ -932,9 +930,7 @@ static int mmc_read_bkops_status(struct mmc_card *card) int err; u8 *ext_csd; - mmc_claim_host(card->host); err = mmc_get_ext_csd(card, &ext_csd); - mmc_release_host(card->host); if (err) return err; -- cgit v1.2.3