From e59d24e61269de34d79d2f39d3d581c219ac7a94 Mon Sep 17 00:00:00 2001 From: Greg Kurz Date: Thu, 6 Feb 2014 17:36:56 +0100 Subject: KVM: PPC: Book3S HV: Fix incorrect userspace exit on ioeventfd write When the guest does an MMIO write which is handled successfully by an ioeventfd, ioeventfd_write() returns 0 (success) and kvmppc_handle_store() returns EMULATE_DONE. Then kvmppc_emulate_mmio() converts EMULATE_DONE to RESUME_GUEST_NV and this causes an exit from the loop in kvmppc_vcpu_run_hv(), causing an exit back to userspace with a bogus exit reason code, typically causing userspace (e.g. qemu) to crash with a message about an unknown exit code. This adds handling of RESUME_GUEST_NV in kvmppc_vcpu_run_hv() in order to fix that. For generality, we define a helper to check for either of the return-to-guest codes we use, RESUME_GUEST and RESUME_GUEST_NV, to make it easy to check for either and provide one place to update if any other return-to-guest code gets defined in future. Since it only affects Book3S HV for now, the helper is added to the kvm_book3s.h header file. We use the helper in two places in kvmppc_run_core() as well for future-proofing, though we don't see RESUME_GUEST_NV in either place at present. [paulus@samba.org - combined 4 patches into one, rewrote description] Suggested-by: Paul Mackerras Signed-off-by: Alexey Kardashevskiy Signed-off-by: Greg Kurz Signed-off-by: Paul Mackerras --- arch/powerpc/include/asm/kvm_book3s.h | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'arch/powerpc/include') diff --git a/arch/powerpc/include/asm/kvm_book3s.h b/arch/powerpc/include/asm/kvm_book3s.h index 83851aabfdc8..bb1e38a23ac7 100644 --- a/arch/powerpc/include/asm/kvm_book3s.h +++ b/arch/powerpc/include/asm/kvm_book3s.h @@ -304,6 +304,11 @@ static inline ulong kvmppc_get_fault_dar(struct kvm_vcpu *vcpu) return vcpu->arch.fault_dar; } +static inline bool is_kvmppc_resume_guest(int r) +{ + return (r == RESUME_GUEST || r == RESUME_GUEST_NV); +} + /* Magic register values loaded into r3 and r4 before the 'sc' assembly * instruction for the OSI hypercalls */ #define OSI_SC_MAGIC_R3 0x113724FA -- cgit v1.2.3-55-g7522