https://bugzilla.kernel.org/show_bug.cgi?id=201685 --- Comment #223 from Guenter Roeck (linux@xxxxxxxxxxxx) --- 4.18.20 seems to be ok, except that my script overburdens it a bit. [ 1088.450369] INFO: task systemd-tmpfile:31954 blocked for more than 120 seconds. [ 1088.450374] Not tainted 4.18.20+ #1 [ 1088.450375] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 1088.450377] systemd-tmpfile D 0 31954 1 0x00000000 [ 1088.450380] Call Trace: [ 1088.450389] __schedule+0x3f1/0x8c0 [ 1088.450392] ? bit_wait+0x60/0x60 [ 1088.450394] schedule+0x36/0x80 [ 1088.450398] io_schedule+0x16/0x40 [ 1088.450400] bit_wait_io+0x11/0x60 [ 1088.450403] __wait_on_bit+0x63/0x90 [ 1088.450405] out_of_line_wait_on_bit+0x8e/0xb0 [ 1088.450408] ? init_wait_var_entry+0x50/0x50 [ 1088.450411] __wait_on_buffer+0x32/0x40 [ 1088.450414] __ext4_get_inode_loc+0x19f/0x3e0 [ 1088.450416] ext4_iget+0x8f/0xc30 There is a key difference, though: With 4.18.20, cfq is active. $ cat /sys/block/sd*/queue/scheduler noop deadline [cfq] noop deadline [cfq] In 4.19, cfq is not available due to commit d5038a13eca72 ("scsi: core: switch to scsi-mq by default"). I'll repeat my tests with SCSI_MQ_DEFAULT disabled on v4.19, and with it enabled on v4.18.20. We know that disabling SCSI_MQ_DEFAULT alone does not help, but maybe there is more than one problem. Any takers for a round of bisects as suggested in #221 ? -- You are receiving this mail because: You are watching the assignee of the bug.
