Hi,
With kernel 5.10-rc3, there is a hung with follow steps:
- mount /dev/sda1 (ext4 filesystem) to directory /mnt;
- run "if=/dev/zero of=test1 bs=1M count=2000" on directory /mnt;
- run "sync"
Hung occurs when sync, at the same time we can see thread jbd2 becomes
"D" state. It is very easy to reproduce, and the issue also
occurs on kernel 5.10-rc1/rc2 (but there is no issue on kernel 5.9-rc4).
When this issue occur, there is sometimes a Call trace with the hung on
kernel 5.10-rc1 as follows:
[ 367.912761] INFO: task jbd2/sdb1-8:3602 blocked for more than 120
seconds.
[ 367.919618] Not tainted 5.10.0-rc1-109488-g32ded76956b6 #948
[ 367.925776] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs"
disables this message.
[ 367.933579] task:jbd2/sdb1-8 state:D stack: 0 pid: 3602
ppid: 2 flags:0x00000028
[ 367.941901] Call trace:
[ 367.944351] __switch_to+0xb8/0x168
[ 367.947840] __schedule+0x30c/0x670
[ 367.951326] schedule+0x70/0x108
[ 367.954550] io_schedule+0x1c/0xe8
[ 367.957948] bit_wait_io+0x18/0x68
[ 367.961346] __wait_on_bit+0x78/0xf0
[ 367.964919] out_of_line_wait_on_bit+0x8c/0xb0
[ 367.969356] __wait_on_buffer+0x30/0x40
[ 367.973188] jbd2_journal_commit_transaction+0x1370/0x1958
[ 367.978661] kjournald2+0xcc/0x260
[ 367.982061] kthread+0x150/0x158
[ 367.985288] ret_from_fork+0x10/0x34
[ 367.988860] INFO: task sync:3823 blocked for more than 120 seconds.
[ 367.995102] Not tainted 5.10.0-rc1-109488-g32ded76956b6 #948
[ 368.001265] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs"
disables this message.
[ 368.009067] task:sync state:D stack: 0 pid: 3823 ppid:
3450 flags:0x00000009
[ 368.017397] Call trace:
[ 368.019841] __switch_to+0xb8/0x168
[ 368.023320] __schedule+0x30c/0x670
[ 368.026804] schedule+0x70/0x108
[ 368.030025] jbd2_log_wait_commit+0xbc/0x158
[ 368.034290] ext4_sync_fs+0x188/0x1c8
[ 368.037947] sync_fs_one_sb+0x30/0x40
[ 368.041606] iterate_supers+0x9c/0x138
[ 368.045350] ksys_sync+0x64/0xc0
[ 368.048569] __arm64_sys_sync+0x10/0x20
[ 368.052398] el0_svc_common.constprop.3+0x68/0x170
[ 368.057177] do_el0_svc+0x24/0x90
[ 368.060482] el0_sync_handler+0x118/0x168
[ 368.064478] el0_sync+0x158/0x180
Do you have any idea about the issue? Please let me know if you want
more info or debug.
Best regard,
Shawn
