On Tue, 28 May 2019, Jiri Kosina wrote: > [ some x86/PM folks added ] > > I isolated this to 'nosmt' being present in the "outer" (resuming) kernel, > and am still not sure whether this is x86 issue or nvme/PCI/blk-mq issue. > > For the newcomers to this thread: on my thinkpad x270, 'nosmt' reliably > breaks resume from hibernation; after the image is read out from disk and > attempt is made to jump to the old kernel, machine reboots.
Thomas figured it out (and this should be really more widespread than just my machine :) ). nosmt forces HT siblings to mwait, but that explodes after %cr3 change during resume, as the mwait target address is all of a sudden not valid anymore for neither of the hyperthreads. That also explains why I apparently didn't see it that regularly with kaslr disabled. Nothing to do with nvme, so let's not continue coming up with proper fix in this thread. Thanks, -- Jiri Kosina SUSE Labs
