This is a note to let you know that I've just added the patch titled
KVM: x86: Don't re-execute instruction when not passing CR2 value
to the 4.14-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...
The filename of the patch is: kvm-x86-don-t-re-execute-instruction-when-not-passing-cr2-value.patch and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.
From foo@baz Thu Feb 1 13:45:42 CET 2018
From: Liran Alon liran.alon@oracle.com Date: Sun, 5 Nov 2017 16:56:34 +0200 Subject: KVM: x86: Don't re-execute instruction when not passing CR2 value
From: Liran Alon liran.alon@oracle.com
[ Upstream commit 9b8ae63798cb97e785a667ff27e43fa6220cb734 ]
In case of instruction-decode failure or emulation failure, x86_emulate_instruction() will call reexecute_instruction() which will attempt to use the cr2 value passed to x86_emulate_instruction(). However, when x86_emulate_instruction() is called from emulate_instruction(), cr2 is not passed (passed as 0) and therefore it doesn't make sense to execute reexecute_instruction() logic at all.
Fixes: 51d8b66199e9 ("KVM: cleanup emulate_instruction")
Signed-off-by: Liran Alon liran.alon@oracle.com Reviewed-by: Nikita Leshenko nikita.leshchenko@oracle.com Reviewed-by: Konrad Rzeszutek Wilk konrad.wilk@oracle.com Signed-off-by: Konrad Rzeszutek Wilk konrad.wilk@oracle.com Reviewed-by: Wanpeng Li wanpeng.li@hotmail.com Signed-off-by: Radim Krčmář rkrcmar@redhat.com Signed-off-by: Sasha Levin alexander.levin@verizon.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/x86/include/asm/kvm_host.h | 3 ++- arch/x86/kvm/vmx.c | 2 +- 2 files changed, 3 insertions(+), 2 deletions(-)
--- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -1156,7 +1156,8 @@ int x86_emulate_instruction(struct kvm_v static inline int emulate_instruction(struct kvm_vcpu *vcpu, int emulation_type) { - return x86_emulate_instruction(vcpu, 0, emulation_type, NULL, 0); + return x86_emulate_instruction(vcpu, 0, + emulation_type | EMULTYPE_NO_REEXECUTE, NULL, 0); }
void kvm_enable_efer_bits(u64); --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -6607,7 +6607,7 @@ static int handle_invalid_guest_state(st if (kvm_test_request(KVM_REQ_EVENT, vcpu)) return 1;
- err = emulate_instruction(vcpu, EMULTYPE_NO_REEXECUTE); + err = emulate_instruction(vcpu, 0);
if (err == EMULATE_USER_EXIT) { ++vcpu->stat.mmio_exits;
Patches currently in stable-queue which might be from liran.alon@oracle.com are
queue-4.14/kvm-nvmx-fix-vmx_check_nested_events-return-value-in-case-an-event-was-reinjected-to-l2.patch queue-4.14/kvm-x86-don-t-re-execute-instruction-when-not-passing-cr2-value.patch queue-4.14/kvm-x86-ioapic-preserve-read-only-values-in-the-redirection-table.patch queue-4.14/kvm-x86-ioapic-fix-level-triggered-eoi-and-ioapic-reconfigure-race.patch queue-4.14/kvm-x86-emulator-return-to-user-mode-on-l1-cpl-0-emulation-failure.patch queue-4.14/kvm-nvmx-nsvm-don-t-intercept-ud-when-running-l2.patch queue-4.14/kvm-x86-ioapic-clear-remote-irr-when-entry-is-switched-to-edge-triggered.patch