[+ 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. 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). 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
