On Tue, Sep 21, 2021 at 06:33:20AM -0400, Chuck Zmudzinski wrote: > I presume you are suggesting I try booting 4.19.181-1 on the > current version of Xen-4.14 for bullseye as a dom0. I am not > inclined to try it until an official Debian developer endorses > your opinion that the bug I am seeing is distinct > from #991967, at which point I will report the bug I am > seeing as a new bug.
Chuck Zmudzinski you are getting rather close to my threshold for calling harrassment. You're not /quite/ there, but I'm concerned. Since the purpose of the bug reports is to find and diagnose bugs, I did a bit of experimentation and made some observations. I checked out the Debian Xen source via git. I got the current "master" branch which is presently the candidate 4.14.3-1 version, which includes urgent fixes. The hash is: e7a17db0305c8de891b366ad37777528e5a43015 On top of this I cherry-picked 3 commits from Xen's main branch: 5a4087004d1adbbb223925f3306db0e5824a2bdc 0f089bbf43ecce6f27576cb548ba4341d0ec46a8 bc141e8ca56200bdd0a12e04a6ebff3c19d6c27b (these can be retrieved via Xen's gitweb at https://xenbits.xen.org/gitweb/?p=xen.git;a=patch;h=<$hash> which is suitable for the `git am` command) With these I built 4.14.3-1 and then tried kernels 4.19.181-1 and 4.19.194-3 (this system is presently mostly on oldstable). The results were: Xen 4.14.3-1 with Linux 4.19.181-1: system reboots were successful Xen 4.14.3-1 with Linux 4.19.194-3: system reboots hung Unfortunately I was too quick at installing the rebuilt 4.14.3-1 and I missed trying the vanilla Debian 4.14.2+25-gb6a8c4f72d-2 with Linux 4.19.181-1. I believe this combination would have hung during reboot. As such, I believe there are in fact two distinct bugs being observed. The presence of EITHER of these is sufficient to cause hangs during powerdown or reboot. First, some patch originally from Linux's main branch breaks Xen reboots was backported somewhere between 4.19.181-1 and 4.19.194-3. This may either have been introduced before 5.10 diverged from main, or may also have been backported to 5.10. THIS is Debian bug #991967. Second, the Xen patch 3c428e9ecb1f290689080c11e0c37b793425bef1 which is valuable to ARM devices breaks reboots and powerdowns on x86. This is correctly fixed by 0f089bbf43ecce6f27576cb548ba4341d0ec46a8. Presently this has no Debian bug report. The first is presently unidentified, someone enthusiastic either needs to read git logs/source code, or bisect and build to find where it got broken. The second we seem to have a fix. The only question is how many patches to cherry pick? bc141e8ca562 is non-urgent as it is merely superficial and not needed for functionality. 5a4087004d1a is a workaround for Linux kernel breakage, but how likely are we to see that fixed in the Linux kernel packages? The fix is well-contained and needed for some highly popular ARM devices. -- (\___(\___(\______ --=> 8-) EHM <=-- ______/)___/)___/) \BS ( | ehem+sig...@m5p.com PGP 87145445 | ) / \_CS\ | _____ -O #include <stddisclaimer.h> O- _____ | / _/ 8A19\___\_|_/58D2 7E3D DDF4 7BA6 <-PGP-> 41D1 B375 37D0 8714\_|_/___/5445
