Re: [PATCH v2 7/9] arm64: KVM: Do not corrupt registers on failed 64bit CP read

2017-03-28 Thread Marc Zyngier
On 28/03/17 13:46, Christoffer Dall wrote: > On Mon, Mar 27, 2017 at 05:03:43PM +0100, Marc Zyngier wrote: >> If we fail to emulate a mrrc instruction, we: >> 1) deliver an exception, >> 2) spit a nastygram on the console, >> 3) write back some garbage to Rt/Rt2 >> >> While 1) and 2) are perfectly

[PATCH v2 7/9] arm64: KVM: Do not corrupt registers on failed 64bit CP read

2017-03-27 Thread Marc Zyngier
If we fail to emulate a mrrc instruction, we: 1) deliver an exception, 2) spit a nastygram on the console, 3) write back some garbage to Rt/Rt2 While 1) and 2) are perfectly acceptable, 3) is out of the scope of the architecture... Let's mimick the code in kvm_handle_cp_32 and be more cautious.