On 11/3/2020 8:55 PM, Ulf Hansson wrote:
On Wed, 28 Oct 2020 at 12:20, Veerabhadrarao Badiganti
<vbadigan@xxxxxxxxxxxxxx> wrote:
The commit bbdc74dc19e0 ("mmc: block: Prevent new req entering queue
after its cleanup") has introduced this change but it got moved after
del_gendisk() with commit 57678e5a3d51 ("mmc: block: Delete gendisk
before cleaning up the request queue").
This isn't the first time we have spotted errors in this path. Seems
like a difficult path to get correct. :-)
It is blocking reboot with below Call stack().
INFO: task reboot:3086 blocked for more than 122 seconds.
__schedule
schedule
schedule_timeout
io_schedule_timeout
do_wait_for_common
wait_for_completion_io
submit_bio_wait
blkdev_issue_flush
ext4_sync_fs
__sync_filesystem
sync_filesystem
fsync_bdev
invalidate_partition
del_gendisk
mmc_blk_remove_req
mmc_blk_remove
mmc_bus_remove
device_release_driver_internal
device_release_driver
bus_remove_device
device_del
mmc_remove_card
mmc_remove
mmc_stop_host
mmc_remove_host
sdhci_remove_host
sdhci_msm_remove
Why do you call sdhci_msm_remove() from the shutdown callback? What
specific operations do you need to run in the shutdown path for sdhci
msm?
I was suggested to add shutdown callback by memory team to gracefully
de-register with smmu driver
during reboot/shutdown. So tried adding it. Since SMMU team.
I just need to ensure that controller is not active anymore and not
accessing memory related to any
requests and de-register with smmu driver during shutdown.
The important part should be to do a graceful shutdown of the card
(and the block device) - is there anything else?
Or you are just using the shutdown callback as a simple way to trigger
this problem? Could unbinding the driver trigger the same issue?
sdhci_msm_shutdown
platform_drv_shutdown
device_shutdown
kernel_restart_prepare
kernel_restart
So bringing this change back.
Signed-off-by: Veerabhadrarao Badiganti <vbadigan@xxxxxxxxxxxxxx>
---
I'm observing this issue 100% of the time with shutdown callback added to sdhci-msm driver.
I'm trying on 5.4 kernel with ChromeOS.
Please let me know if this can be fixed in a better way.
I don't know yet, but I will have a closer look. Let's also see if
Adrian has some thoughts.
Kind regards
Uffe
---
drivers/mmc/core/block.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c
index 8d3df0be0355..76dbb2b8a13b 100644
--- a/drivers/mmc/core/block.c
+++ b/drivers/mmc/core/block.c
@@ -2627,6 +2627,7 @@ static void mmc_blk_remove_req(struct mmc_blk_data *md)
* from being accepted.
*/
card = md->queue.card;
+ blk_set_queue_dying(md->queue.queue);
if (md->disk->flags & GENHD_FL_UP) {
device_remove_file(disk_to_dev(md->disk), &md->force_ro);
if ((md->area_type & MMC_BLK_DATA_AREA_BOOT) &&
--
Qualcomm India Private Limited, on behalf of Qualcomm Innovation Center, Inc., is a member of Code Aurora Forum, a Linux Foundation Collaborative Project
