From: Coly Li colyli@suse.de
[ Upstream commit 4243219141b67d7c2fdb2d8073c17c539b9263eb ]
In mmc_queue_setup_discard() the mmc driver queue's discard_granularity might be set as 0 (when card->pref_erase > max_discard) while the mmc device still declares to support discard operation. This is buggy and triggered the following kernel warning message,
WARNING: CPU: 0 PID: 135 at __blkdev_issue_discard+0x200/0x294 CPU: 0 PID: 135 Comm: f2fs_discard-17 Not tainted 5.9.0-rc6 #1 Hardware name: Google Kevin (DT) pstate: 00000005 (nzcv daif -PAN -UAO BTYPE=--) pc : __blkdev_issue_discard+0x200/0x294 lr : __blkdev_issue_discard+0x54/0x294 sp : ffff800011dd3b10 x29: ffff800011dd3b10 x28: 0000000000000000 x27: ffff800011dd3cc4 x26: ffff800011dd3e18 x25: 000000000004e69b x24: 0000000000000c40 x23: ffff0000f1deaaf0 x22: ffff0000f2849200 x21: 00000000002734d8 x20: 0000000000000008 x19: 0000000000000000 x18: 0000000000000000 x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000 x14: 0000000000000394 x13: 0000000000000000 x12: 0000000000000000 x11: 0000000000000000 x10: 00000000000008b0 x9 : ffff800011dd3cb0 x8 : 000000000004e69b x7 : 0000000000000000 x6 : ffff0000f1926400 x5 : ffff0000f1940800 x4 : 0000000000000000 x3 : 0000000000000c40 x2 : 0000000000000008 x1 : 00000000002734d8 x0 : 0000000000000000 Call trace: __blkdev_issue_discard+0x200/0x294 __submit_discard_cmd+0x128/0x374 __issue_discard_cmd_orderly+0x188/0x244 __issue_discard_cmd+0x2e8/0x33c issue_discard_thread+0xe8/0x2f0 kthread+0x11c/0x120 ret_from_fork+0x10/0x1c ---[ end trace e4c8023d33dfe77a ]---
This patch fixes the issue by setting discard_granularity as SECTOR_SIZE instead of 0 when (card->pref_erase > max_discard) is true. Now no more complain from __blkdev_issue_discard() for the improper value of discard granularity.
This issue is exposed after commit b35fd7422c2f ("block: check queue's limits.discard_granularity in __blkdev_issue_discard()"), a "Fixes:" tag is also added for the commit to make sure people won't miss this patch after applying the change of __blkdev_issue_discard().
Fixes: e056a1b5b67b ("mmc: queue: let host controllers specify maximum discard timeout") Fixes: b35fd7422c2f ("block: check queue's limits.discard_granularity in __blkdev_issue_discard()"). Reported-and-tested-by: Vicente Bergas vicencb@gmail.com Signed-off-by: Coly Li colyli@suse.de Acked-by: Adrian Hunter adrian.hunter@intel.com Cc: Ulf Hansson ulf.hansson@linaro.org Link: https://lore.kernel.org/r/20201002013852.51968-1-colyli@suse.de Signed-off-by: Ulf Hansson ulf.hansson@linaro.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/mmc/core/queue.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/mmc/core/queue.c b/drivers/mmc/core/queue.c index 2a788169cbb8..9b31cd6b6062 100644 --- a/drivers/mmc/core/queue.c +++ b/drivers/mmc/core/queue.c @@ -185,7 +185,7 @@ static void mmc_queue_setup_discard(struct request_queue *q, q->limits.discard_granularity = card->pref_erase << 9; /* granularity must not be greater than max. discard */ if (card->pref_erase > max_discard) - q->limits.discard_granularity = 0; + q->limits.discard_granularity = SECTOR_SIZE; if (mmc_can_secure_erase_trim(card)) blk_queue_flag_set(QUEUE_FLAG_SECERASE, q); }