On 21/01/18 12:32, gregkh@xxxxxxxxxxxxxxxxxxx wrote: > > This is a note to let you know that I've just added the patch titled > > arm64: KVM: Fix SMCCC handling of unimplemented SMC/HVC calls > > to the 3.18-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: > arm64-kvm-fix-smccc-handling-of-unimplemented-smc-hvc-calls.patch > and it can be found in the queue-3.18 subdirectory. > > If you, or anyone else, feels it should not be added to the stable tree, > please let <stable@xxxxxxxxxxxxxxx> know about it. > > > From acfb3b883f6d6a4b5d27ad7fdded11f6a09ae6dd Mon Sep 17 00:00:00 2001 > From: Marc Zyngier <marc.zyngier@xxxxxxx> > Date: Tue, 16 Jan 2018 10:23:47 +0000 > Subject: arm64: KVM: Fix SMCCC handling of unimplemented SMC/HVC calls > > From: Marc Zyngier <marc.zyngier@xxxxxxx> > > commit acfb3b883f6d6a4b5d27ad7fdded11f6a09ae6dd upstream. > > KVM doesn't follow the SMCCC when it comes to unimplemented calls, > and inject an UNDEF instead of returning an error. Since firmware > calls are now used for security mitigation, they are becoming more > common, and the undef is counter productive. > > Instead, let's follow the SMCCC which states that -1 must be returned > to the caller when getting an unknown function number. > > Signed-off-by: Marc Zyngier <marc.zyngier@xxxxxxx> > Signed-off-by: Christoffer Dall <christoffer.dall@xxxxxxxxxx> > Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> > > --- > arch/arm64/kvm/handle_exit.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > --- a/arch/arm64/kvm/handle_exit.c > +++ b/arch/arm64/kvm/handle_exit.c > @@ -34,7 +34,7 @@ static int handle_hvc(struct kvm_vcpu *v > > ret = kvm_psci_call(vcpu); > if (ret < 0) { > - kvm_inject_undefined(vcpu); > + vcpu_set_reg(vcpu, 0, ~0UL); > return 1; > } > > @@ -43,7 +43,7 @@ static int handle_hvc(struct kvm_vcpu *v > > static int handle_smc(struct kvm_vcpu *vcpu, struct kvm_run *run) > { > - kvm_inject_undefined(vcpu); > + vcpu_set_reg(vcpu, 0, ~0UL); > return 1; > } > > > > Patches currently in stable-queue which might be from marc.zyngier@xxxxxxx are > > queue-3.18/arm64-kvm-fix-smccc-handling-of-unimplemented-smc-hvc-calls.patch This doesn't compile on 3.18. Here's the 3.18 fix: >From 1dd2c482cc168ebe2d099db0ea7b2a5ca239c182 Mon Sep 17 00:00:00 2001 From: Marc Zyngier <marc.zyngier@xxxxxxx> Date: Fri, 12 Jan 2018 07:34:43 +0000 Subject: [PATCH] arm64: KVM: Fix SMCCC handling of unimplemented SMC/HVC calls commit acfb3b883f6d6a4b5d27ad7fdded11f6a09ae6dd upstream. KVM doesn't follow the SMCCC when it comes to unimplemented calls, and inject an UNDEF instead of returning an error. Since firmware calls are now used for security mitigation, they are becoming more common, and the undef is counter productive. Instead, let's follow the SMCCC which states that -1 must be returned to the caller when getting an unknown function number. Signed-off-by: Marc Zyngier <marc.zyngier@xxxxxxx> Signed-off-by: Christoffer Dall <christoffer.dall@xxxxxxxxxx> --- arch/arm64/kvm/handle_exit.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/arm64/kvm/handle_exit.c b/arch/arm64/kvm/handle_exit.c index 34b8bd0711e9..e738bff5eec1 100644 --- a/arch/arm64/kvm/handle_exit.c +++ b/arch/arm64/kvm/handle_exit.c @@ -34,7 +34,7 @@ static int handle_hvc(struct kvm_vcpu *vcpu, struct kvm_run *run) ret = kvm_psci_call(vcpu); if (ret < 0) { - kvm_inject_undefined(vcpu); + *vcpu_reg(vcpu, 0) = ~0UL; return 1; } @@ -43,7 +43,7 @@ static int handle_hvc(struct kvm_vcpu *vcpu, struct kvm_run *run) static int handle_smc(struct kvm_vcpu *vcpu, struct kvm_run *run) { - kvm_inject_undefined(vcpu); + *vcpu_reg(vcpu, 0) = ~0UL; return 1; } -- 2.14.2 -- Jazz is not dead. It just smells funny...