On Wednesday 11 November 2009, Ferenc Wagner wrote: > "Rafael J. Wysocki" <rjw@xxxxxxx> writes: > > > On Thursday 29 October 2009, Ferenc Wagner wrote: > > > >> "Rafael J. Wysocki" <rjw@xxxxxxx> writes: > >> > >>> On Wednesday 28 October 2009, Ferenc Wagner wrote: > >>> > >>>> 2.6.32-rc5 feels particularly bad, with frequent failures to switch > >>>> off the machine after "S|" or freezes after "Snapshotting system". > >>>> The former does not cause much trouble in itself, as the machine can > >>>> be switched off and resumed all right, but the latter is nasty. > >>>> Suspend to RAM works all the time. The issue is not reproducible, > >>>> unfortunately, and the kernel change happened almost together with a > >>>> BIOS upgrade. Yesterday I switched back to 2.6.31 to see whether it > >>>> still works stably with the new BIOS. I'll report back my findings in > >>>> a couple of days. > >>> > >>> OK, thanks. > >>> > >>> Still, I'm really afraid we won't be able to debug it any further without a > >>> reproducible test case. > >> > >> Can't you perhaps suggest a way forward there? Or some tricks to create a > >> reproducible test case here? > > > > Well, you can test if the problem is reproducible in the "shutdown" mode of > > hibernation. > > Well, both failure modes happen with "shutdown" mode as well (the S| > freeze with yesterday's git, too), but still not reproducibly. When > s2disk is stuck in "Snapshotting system", the system is not completely > dead, it echoes line feeds and Ctrl-C at least (as added to #14504). > > I wonder what you did if the issue was reproducible... Is that totally > unapplicable if the problem happens with 10% probability only? Slow, > sure, but until I manage to set up an automated testing bench... I would try to identify the commit that made the problem appear using git bisection. However, this is really difficult with problems that are not reliably reproducible. Failing that, I would add some instrumentation to the code to identify the exact place where it hangs. BTW, did you carry out the /sys/power/pm_test "core" test on the box? Rafael -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
