From 002374f371bd02df864cce1fe85d90dc5b292837 Mon Sep 17 00:00:00 2001 From: James Hogan Date: Wed, 11 Nov 2015 14:21:18 +0000 Subject: [PATCH] MIPS: KVM: Fix ASID restoration logic ASID restoration on guest resume should determine the guest execution mode based on the guest Status register rather than bit 30 of the guest PC. Fix the two places in locore.S that do this, loading the guest status from the cop0 area. Note, this assembly is specific to the trap & emulate implementation of KVM, so it doesn't need to check the supervisor bit as that mode is not implemented in the guest. Fixes: b680f70fc111 ("KVM/MIPS32: Entry point for trampolining to...") Signed-off-by: James Hogan Cc: Ralf Baechle Cc: Paolo Bonzini Cc: Gleb Natapov Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org Cc: # 3.10.x- Signed-off-by: Paolo Bonzini --- arch/mips/kvm/locore.S | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-) diff --git a/arch/mips/kvm/locore.S b/arch/mips/kvm/locore.S index 7bab3a4e8f7d..7e2210846b8b 100644 --- a/arch/mips/kvm/locore.S +++ b/arch/mips/kvm/locore.S @@ -157,9 +157,11 @@ FEXPORT(__kvm_mips_vcpu_run) FEXPORT(__kvm_mips_load_asid) /* Set the ASID for the Guest Kernel */ - INT_SLL t0, t0, 1 /* with kseg0 @ 0x40000000, kernel */ - /* addresses shift to 0x80000000 */ - bltz t0, 1f /* If kernel */ + PTR_L t0, VCPU_COP0(k1) + LONG_L t0, COP0_STATUS(t0) + andi t0, KSU_USER | ST0_ERL | ST0_EXL + xori t0, KSU_USER + bnez t0, 1f /* If kernel */ INT_ADDIU t1, k1, VCPU_GUEST_KERNEL_ASID /* (BD) */ INT_ADDIU t1, k1, VCPU_GUEST_USER_ASID /* else user */ 1: @@ -474,9 +476,11 @@ __kvm_mips_return_to_guest: mtc0 t0, CP0_EPC /* Set the ASID for the Guest Kernel */ - INT_SLL t0, t0, 1 /* with kseg0 @ 0x40000000, kernel */ - /* addresses shift to 0x80000000 */ - bltz t0, 1f /* If kernel */ + PTR_L t0, VCPU_COP0(k1) + LONG_L t0, COP0_STATUS(t0) + andi t0, KSU_USER | ST0_ERL | ST0_EXL + xori t0, KSU_USER + bnez t0, 1f /* If kernel */ INT_ADDIU t1, k1, VCPU_GUEST_KERNEL_ASID /* (BD) */ INT_ADDIU t1, k1, VCPU_GUEST_USER_ASID /* else user */ 1: -- 2.39.2