This is a note to let you know that I've just added the patch titled

KVM: x86: ioapic: Preserve read-only values in the redirection table

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-ioapic-preserve-read-only-values-in-the-redirection-table.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: Nikita Leshenko nikita.leshchenko@oracle.com Date: Sun, 5 Nov 2017 15:52:33 +0200 Subject: KVM: x86: ioapic: Preserve read-only values in the redirection table

From: Nikita Leshenko nikita.leshchenko@oracle.com

[ Upstream commit b200dded0a6974a3b69599832b2203483920ab25 ]

According to 82093AA (IOAPIC) manual, Remote IRR and Delivery Status are read-only. QEMU implements the bits as RO in commit 479c2a1cb7fb ("ioapic: keep RO bits for IOAPIC entry").

Signed-off-by: Nikita Leshenko nikita.leshchenko@oracle.com Reviewed-by: Liran Alon liran.alon@oracle.com Signed-off-by: Konrad Rzeszutek Wilk konrad.wilk@oracle.com Reviewed-by: Wanpeng Li wanpeng.li@hotmail.com Reviewed-by: Steve Rutherford srutherford@google.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/kvm/ioapic.c | 6 ++++++ 1 file changed, 6 insertions(+)

--- a/arch/x86/kvm/ioapic.c +++ b/arch/x86/kvm/ioapic.c @@ -276,6 +276,7 @@ static void ioapic_write_indirect(struct { unsigned index; bool mask_before, mask_after; + int old_remote_irr, old_delivery_status; union kvm_ioapic_redirect_entry *e;

switch (ioapic->ioregsel) { @@ -298,6 +299,9 @@ static void ioapic_write_indirect(struct return; e = &ioapic->redirtbl[index]; mask_before = e->fields.mask; + /* Preserve read-only fields */ + old_remote_irr = e->fields.remote_irr; + old_delivery_status = e->fields.delivery_status; if (ioapic->ioregsel & 1) { e->bits &= 0xffffffff; e->bits |= (u64) val << 32; @@ -305,6 +309,8 @@ static void ioapic_write_indirect(struct e->bits &= ~0xffffffffULL; e->bits |= (u32) val; } + e->fields.remote_irr = old_remote_irr; + e->fields.delivery_status = old_delivery_status;

/* * Some OSes (Linux, Xen) assume that Remote IRR bit will

Patches currently in stable-queue which might be from nikita.leshchenko@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