[Qemu-devel] About Revert this patch: arm: Allow system registers for KVM guests to be changed by QEMU code

[gengdongjiu]

 Hi   Peter/Eric,
   I think we should fix the regression issue instead of revert this patch,  I 
think the reason of
   this issue is that QEMU modified some unexpected resisters, we should find 
out.


    Revert "arm: Allow system registers for KVM guests to be changed by QEMU 
code"

    This reverts commit 823e1b3818f9b10b824ddcd756983b6e2fa68730,
    which introduces a regression running EDK2 guest firmware
    under KVM:

    error: kvm run failed Function not implemented
     PC=000000013f5a6208 X00=00000000404003c4 X01=000000000000003a
    X02=0000000000000000 X03=00000000404003c4 X04=0000000000000000
    X05=0000000096000046 X06=000000013d2ef270 X07=000000013e3d1710
    X08=09010755ffaf8ba8 X09=ffaf8b9cfeeb5468 X10=feeb546409010756
    X11=09010757ffaf8b90 X12=feeb50680903068b X13=090306a1ffaf8bc0
    X14=0000000000000000 X15=0000000000000000 X16=000000013f872da0
    X17=00000000ffffa6ab X18=0000000000000000 X19=000000013f5a92d0
    X20=000000013f5a7a78 X21=000000000000003a X22=000000013f5a7ab2
    X23=000000013f5a92e8 X24=000000013f631090 X25=0000000000000010
    X26=0000000000000100 X27=000000013f89501b X28=000000013e3d14e0
    X29=000000013e3d12a0 X30=000000013f5a2518  SP=000000013b7be0b0
    PSTATE=404003c4 -Z-- EL1t

    with
    [ 3507.926571] kvm [35042]: load/store instruction decoding not implemented
    in the host dmesg.

    Revert the change for the moment until we can investigate the
    cause of the regression.

    Reported-by: Eric Auger <address@hidden>
    Signed-off-by: Peter Maydell <address@hidden>