From 7b5b4df1a79954e0b208630fc63b16ec0231a516 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Mon, 27 Mar 2017 17:03:40 +0100 Subject: arm64: KVM: Make unexpected reads from WO registers inject an undef Reads from write-only system registers are generally confined to EL1 and not propagated to EL2 (that's what the architecture mantates). In order to be sure that we have a sane behaviour even in the unlikely event that we have a broken system, we still handle it in KVM. In that case, let's inject an undef into the guest. Let's also remove write_to_read_only which isn't used anywhere. Reviewed-by: Christoffer Dall Signed-off-by: Marc Zyngier --- arch/arm64/kvm/sys_regs.c | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'arch/arm64/kvm/sys_regs.c') diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index d343c0febdd6..20f90c01af33 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -55,6 +55,15 @@ * 64bit interface. */ +static bool read_from_write_only(struct kvm_vcpu *vcpu, + const struct sys_reg_params *params) +{ + WARN_ONCE(1, "Unexpected sys_reg read to write-only register\n"); + print_sys_reg_instr(params); + kvm_inject_undefined(vcpu); + return false; +} + /* 3 bits per cache level, as per CLIDR, but non-existent caches always 0 */ static u32 cache_levels; -- cgit v1.2.3-59-g8ed1b