On 03/12/15 09:58, Pavel Fedin wrote: > ARM64 CPU has zero register which is read-only, with a value of 0. > However, KVM currently incorrectly recognizes it being SP (because > Rt == 31, and in struct user_pt_regs 'regs' array is followed by SP), > resulting in invalid value being read, or even SP corruption on write.
No really. XZR and SP do share the same encoding. > The problem has been discovered by performing an operation > > *((volatile int *)reg) = 0; > > which compiles as "str xzr, [xx]", and resulted in strange values being > written. Interesting find. Which compiler is that? Thanks, M. -- Jazz is not dead. It just smells funny... -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html