On Tue, Dec 8, 2020 at 9:37 AM Julia Lawall <julia.lawall@xxxxxxxx> wrote: > > We have not succeeded to boot 5.10 on our Intel(R) Xeon(R) CPU E7-8870 v4 @ > 2.10GHz server. Previous versions (eg 4.19 - 5.9) boot fine. We have > tried various rcs. So the problem started with rc1? Could you try bisecting - even partially? If you do only six bisections, the number of suspect commits drops from 15k to about 230 - which likely pinpoints the suspect area. That said, your traces certainly makes me go "Hmm. Some thing broke in SCSI device scanning", with the primary one being the wait_for_completion() one - the rest of the stuck processes seem to be stuck in async_synchronize_cookie_domain() and are presumably waiting for this kthread that is waiting for the scan to finish. So I'm adding SCSI people to the cc, just in case they go "Hmm..". Martin & co - in the next email Julia also quotes > [ 51.355655][ T7] scsi 0:0:14:0: Direct-Access ATA ST2000LM015-2E81 SDM1 PQ: 0 ANSI: 6 > Gave up waiting for root file system device. Common problems:[..] which seems to be more of the same pattern with the SCSI scanning failure. Of course, it could be some non-scsi patch that causes this, but.. A bisect would hopefully clarify. Leaving the (simplified) backtrace quoted below. Linus >The backtrace for rc7 is shown below. > > [ 253.207171][ T979] INFO: task kworker/u321:2:1278 blocked for more than 120 seconds. > [ 253.224089][ T979] Tainted: G E 5.10.0-rc7 #3 > [ 253.239209][ T979] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. > [ 253.256990][ T979] task:kworker/u321:2 state:D stack: 0 pid: 1278 ppid: 2 flags:0x00004000 > [ 253.275552][ T979] Workqueue: events_unbound async_run_entry_fn > [ 253.290687][ T979] Call Trace: > [ 253.302491][ T979] __schedule+0x31e/0x890 > [ 253.315353][ T979] schedule+0x3c/0xa0 > [ 253.327688][ T979] schedule_timeout+0x274/0x310 > [ 253.379283][ T979] wait_for_completion+0x8a/0xf0 > [ 253.392327][ T979] scsi_complete_async_scans+0x107/0x170 > [ 253.406115][ T979] __scsi_add_device+0xf7/0x130 > [ 253.418974][ T979] ata_scsi_scan_host+0x98/0x1c0 > [ 253.431948][ T979] async_run_entry_fn+0x39/0x160 > [ 253.444853][ T979] process_one_work+0x24c/0x490