From f6edbbf36da3a27b298b66c7955fc84e1dcca305 Mon Sep 17 00:00:00 2001 From: Pranavkumar Sawargaonkar Date: Thu, 31 Jul 2014 12:23:23 +0530 Subject: ARM/ARM64: KVM: Nuke Hyp-mode tlbs before enabling MMU X-Gene u-boot runs in EL2 mode with MMU enabled hence we might have stale EL2 tlb enteris when we enable EL2 MMU on each host CPU. This can happen on any ARM/ARM64 board running bootloader in Hyp-mode (or EL2-mode) with MMU enabled. This patch ensures that we flush all Hyp-mode (or EL2-mode) TLBs on each host CPU before enabling Hyp-mode (or EL2-mode) MMU. Cc: Tested-by: Mark Rutland Reviewed-by: Marc Zyngier Signed-off-by: Pranavkumar Sawargaonkar Signed-off-by: Anup Patel Signed-off-by: Christoffer Dall --- arch/arm/kvm/init.S | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'arch/arm') diff --git a/arch/arm/kvm/init.S b/arch/arm/kvm/init.S index 991415d978b6..3988e72d16ff 100644 --- a/arch/arm/kvm/init.S +++ b/arch/arm/kvm/init.S @@ -99,6 +99,10 @@ __do_hyp_init: mrc p15, 0, r0, c10, c2, 1 mcr p15, 4, r0, c10, c2, 1 + @ Invalidate the stale TLBs from Bootloader + mcr p15, 4, r0, c8, c7, 0 @ TLBIALLH + dsb ish + @ Set the HSCTLR to: @ - ARM/THUMB exceptions: Kernel config (Thumb-2 kernel) @ - Endianness: Kernel config -- cgit v1.2.1 From 05e0127f9e362b36aa35f17b1a3d52bca9322a3a Mon Sep 17 00:00:00 2001 From: Christoffer Dall Date: Tue, 26 Aug 2014 14:33:02 +0200 Subject: arm/arm64: KVM: Complete WFI/WFE instructions The architecture specifies that when the processor wakes up from a WFE or WFI instruction, the instruction is considered complete, however we currrently return to EL1 (or EL0) at the WFI/WFE instruction itself. While most guests may not be affected by this because their local exception handler performs an exception returning setting the event bit or with an interrupt pending, some guests like UEFI will get wedged due this little mishap. Simply skip the instruction when we have completed the emulation. Cc: Acked-by: Marc Zyngier Cc: Ard Biesheuvel Signed-off-by: Christoffer Dall --- arch/arm/kvm/handle_exit.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'arch/arm') diff --git a/arch/arm/kvm/handle_exit.c b/arch/arm/kvm/handle_exit.c index 4c979d466cc1..a96a8043277c 100644 --- a/arch/arm/kvm/handle_exit.c +++ b/arch/arm/kvm/handle_exit.c @@ -93,6 +93,8 @@ static int kvm_handle_wfx(struct kvm_vcpu *vcpu, struct kvm_run *run) else kvm_vcpu_block(vcpu); + kvm_skip_instr(vcpu, kvm_vcpu_trap_il_is32bit(vcpu)); + return 1; } -- cgit v1.2.1