From 42e35f8072c339cbdcaf4de95dc6e1815c2797cf Mon Sep 17 00:00:00 2001 From: KarimAllah Ahmed Date: Thu, 31 Jan 2019 21:24:39 +0100 Subject: [PATCH] KVM/X86: Use kvm_vcpu_map in emulator_cmpxchg_emulated Use kvm_vcpu_map in emulator_cmpxchg_emulated since using kvm_vcpu_gpa_to_page() and kmap() will only work for guest memory that has a "struct page". Signed-off-by: KarimAllah Ahmed Reviewed-by: Konrad Rzeszutek Wilk Signed-off-by: Paolo Bonzini --- arch/x86/kvm/x86.c | 14 ++++++-------- 1 file changed, 6 insertions(+), 8 deletions(-) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index a7ea346fa41e..044ece3a28a4 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -5557,9 +5557,9 @@ static int emulator_cmpxchg_emulated(struct x86_emulate_ctxt *ctxt, unsigned int bytes, struct x86_exception *exception) { + struct kvm_host_map map; struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt); gpa_t gpa; - struct page *page; char *kaddr; bool exchanged; @@ -5576,12 +5576,11 @@ static int emulator_cmpxchg_emulated(struct x86_emulate_ctxt *ctxt, if (((gpa + bytes - 1) & PAGE_MASK) != (gpa & PAGE_MASK)) goto emul_write; - page = kvm_vcpu_gfn_to_page(vcpu, gpa >> PAGE_SHIFT); - if (is_error_page(page)) + if (kvm_vcpu_map(vcpu, gpa_to_gfn(gpa), &map)) goto emul_write; - kaddr = kmap_atomic(page); - kaddr += offset_in_page(gpa); + kaddr = map.hva + offset_in_page(gpa); + switch (bytes) { case 1: exchanged = CMPXCHG_TYPE(u8, kaddr, old, new); @@ -5598,13 +5597,12 @@ static int emulator_cmpxchg_emulated(struct x86_emulate_ctxt *ctxt, default: BUG(); } - kunmap_atomic(kaddr); - kvm_release_page_dirty(page); + + kvm_vcpu_unmap(vcpu, &map, true); if (!exchanged) return X86EMUL_CMPXCHG_FAILED; - kvm_vcpu_mark_page_dirty(vcpu, gpa >> PAGE_SHIFT); kvm_page_track_write(vcpu, gpa, new, bytes); return X86EMUL_CONTINUE; -- 2.30.2