On Wed, 19 Jan 2022 at 04:03, Alexey Kardashevskiy <a...@ozlabs.ru> wrote: > > > > On 1/17/22 03:45, Peter Maydell wrote: > > On Fri, 7 Jan 2022 at 07:29, Alexey Kardashevskiy <a...@ozlabs.ru> wrote: > >> > >> "PowerPC Processor binding to IEEE 1275" says in > >> "8.2.1. Initial Register Values" that the initial state is defined as > >> 32bit so do it for both SLOF and VOF. > >> > >> This should not cause behavioral change as SLOF switches to 64bit very > >> early anyway. As nothing enforces LE anywhere, this drops it for VOF. > >> > >> The goal is to make VOF work with TCG as otherwise it barfs with > >> qemu: fatal: TCG hflags mismatch (current:0x6c000004 rebuilt:0x6c000000) > > > > If you get this assert it means that something is changing > > the CPU state and not calling the function to recalculate > > the hflags (which are basically caching part of the CPU state). > > So I don't know whether this patch is correct or not in updating > > MSR bits, but in any case I think it is only masking the > > missing-hflags-update that is causing the assertion... > > > If we emulate a bare metal machine, then most likely we want MSR_SF > (==64bit) set. But this particular case is paravirtual pseries/spapr and > it requires special handling so spapr_reset_vcpu() seems to be the right > place.
That may be so, but my point remains: if you are getting hflags mismatch asserts then something is failing to recalculate the hflags after updating CPU state. -- PMM
