Hi, On Mon, Apr 25, 2022 at 06:14:13PM +0100, Marc Zyngier wrote: > [+ Oliver] > > Hi Alex, > > On Mon, 25 Apr 2022 15:55:30 +0100, > Alexandru Elisei <alexandru.elisei@xxxxxxx> wrote: > > > > kvm->arch.arm_pmu is set when userspace attempts to set the first PMU > > attribute. As certain attributes are mandatory, arm_pmu ends up always > > being set to a valid arm_pmu, otherwise KVM will refuse to run the VCPU. > > However, this only happens if the VCPU has the PMU feature. If the VCPU > > doesn't have the feature bit set, kvm->arch.arm_pmu will be left > > uninitialized and equal to NULL. > > Although I'm not opposed to this as an immediate workaround to avoid > the ugly crash, I think sanitising the AArch32 regs is the way to go. I agree. This patch is just a band-aid. > Oliver had a stab at this a few weeks back[1], but this seem to have > stalled. > > Could you have a look and see if anything was missing (the patches > needed some rework, but I haven't checked whether DFR0 was correctly > handled or not). I'll have a look. Thanks, Alex > > Thanks, > > M. > > [1] https://lore.kernel.org/r/20220401010832.3425787-1-oupton@xxxxxxxxxx > > -- > Without deviation from the norm, progress is not possible. _______________________________________________ kvmarm mailing list kvmarm@xxxxxxxxxxxxxxxxxxxxx https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
