On 9/5/18 2:55 AM, Mike Galbraith wrote: > Greetings, > > I've been seeing $subject, decided to take the time to try to bisect > the little bugger. The hangs are not 100% repeatable, and while > bisection with a 5 boot go/nogo threshold seemed to go smoothly, it > ended up fingering a merge commit (sigh). > > Box has an SSD (unused only by windows 10 box came with) and 3 spinning > rust buckets that I normally use with BFQ via a udev rule, but CFQ does > the same, so scheduler is seemingly irrelevant. However, in 7 crash > dumps, all of which look about like the data below the bisect log, > there is something relevant, namely the hung 'tlp' task (powersaving > script of some sort for laptops according to the package description). > That knob twiddling script is present/hung in all, making me a tad > suspicious, and indeed, testing with the final (bad) kernel, all I have > to do to eliminate hangs is to remove the 'tlp' package. Verified via > remove, 5 boots work fine, reinstall, 2 of 5 hang, remove again, 10 of > 10 work fine, reinstall, 2 in a row hang. > > Seems pretty certain that tlp script is what inspires bug to raise its > ugly head. WRT bisection result itself, munged merge seems far less > likely than a false negative having knocked bisection off course. > > 72f02ba66bd83b54054da20eae550123de84da6f is the first bad commit
I bet it's the host busy change from Ming, which I already reported as being the culprit for another test failure I had. For some reason it's not merged yet, nudge nudge Martin. You can test by reverting: commit 328728630d9f2bf14b82ca30b5e47489beefe361 Author: Ming Lei <[email protected]> Date: Sun Jun 24 22:03:27 2018 +0800 scsi: core: avoid host-wide host_busy counter for scsi_mq which was slightly modified by 265d59aacbce, so you'll want to yank that one first. BTW, that suse email for me hasn't worked in 12 years :-) -- Jens Axboe
