From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:57594 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754338AbeDIUC4 (ORCPT ); Mon, 9 Apr 2018 16:02:56 -0400 Subject: Patch "KVM: arm: Restore banked registers and physical timer access on hyp_panic()" has been added to the 4.9-stable tree To: james.morse@arm.com, alexander.levin@microsoft.com, cdall@linaro.org, gregkh@linuxfoundation.org, marc.zyngier@arm.com Cc: , From: Date: Mon, 09 Apr 2018 21:58:29 +0200 Message-ID: <1523303909233107@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled KVM: arm: Restore banked registers and physical timer access on hyp_panic() to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: kvm-arm-restore-banked-registers-and-physical-timer-access-on-hyp_panic.patch and it can be found in the queue-4.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From foo@baz Mon Apr 9 17:09:24 CEST 2018 From: James Morse Date: Tue, 25 Apr 2017 18:02:44 +0100 Subject: KVM: arm: Restore banked registers and physical timer access on hyp_panic() From: James Morse [ Upstream commit d2e19368848ce6065daa785efca26faed54732b6 ] When KVM panics, it hurridly restores the host context and parachutes into the host's panic() code. This looks like it was copied from arm64, the 32bit KVM panic code needs to restore the host's banked registers too. At some point panic() touches the physical timer/counter, this will trap back to HYP. If we're lucky, we panic again. Add a __timer_save_state() call to KVMs hyp_panic() path, this saves the guest registers and disables the traps for the host. Fixes: c36b6db5f3e4 ("ARM: KVM: Add panic handling code") Signed-off-by: James Morse Reviewed-by: Marc Zyngier Reviewed-by: Christoffer Dall Signed-off-by: Christoffer Dall Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- arch/arm/kvm/hyp/switch.c | 2 ++ 1 file changed, 2 insertions(+) --- a/arch/arm/kvm/hyp/switch.c +++ b/arch/arm/kvm/hyp/switch.c @@ -237,8 +237,10 @@ void __hyp_text __noreturn __hyp_panic(i vcpu = (struct kvm_vcpu *)read_sysreg(HTPIDR); host_ctxt = kern_hyp_va(vcpu->arch.host_cpu_context); + __timer_save_state(vcpu); __deactivate_traps(vcpu); __deactivate_vm(vcpu); + __banked_restore_state(host_ctxt); __sysreg_restore_state(host_ctxt); } Patches currently in stable-queue which might be from james.morse@arm.com are queue-4.9/kvm-arm-restore-banked-registers-and-physical-timer-access-on-hyp_panic.patch queue-4.9/kvm-arm64-restore-host-physical-timer-access-on-hyp_panic.patch