Re: Patch "arm64: KVM: Fix decoding of Rt/Rt2 when trapping AArch32 CP accesses" has been added to the 4.4-stable tree

[Marc Zyngier <marc.zyngier@arm.com>]

On Wed, May 17 2017 at 09:33:22 AM, Greg KH <gregkh@linuxfoundation.org> wrote:
> On Wed, May 17, 2017 at 07:59:05AM +0100, Marc Zyngier wrote:
>> Hi Greg,
>> 
>> On Tue, May 16 2017 at 11:53:26 AM, <gregkh@linuxfoundation.org> wrote:
>> > This is a note to let you know that I've just added the patch titled
>> >
>> >     arm64: KVM: Fix decoding of Rt/Rt2 when trapping AArch32 CP accesses
>> >
>> > to the 4.4-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-decoding-of-rt-rt2-when-trapping-aarch32-cp-accesses.patch
>> > and it can be found in the queue-4.4 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.
>> 
>> Please drop this patch from 4.4, it doesn't compile (missing crucial
>> dependencies, reported by the kbuild robot). I'll provide an updated
>> patch early next week (unless someone beats me to it -- I'm traveling
>> ATM).
>
> Ok, now dropped, thanks for letting me know.

Here's the updated patch that compiles for 4.4.

Thanks,

	M.

>From 8cafd49862b5f88f68392c4623ec2d275b573d53 Mon Sep 17 00:00:00 2001
From: Marc Zyngier <marc.zyngier@arm.com>
Date: Thu, 27 Apr 2017 19:06:48 +0100
Subject: [PATCH] arm64: KVM: Fix decoding of Rt/Rt2 when trapping AArch32 CP
 accesses

commit c667186f1c01ca8970c785888868b7ffd74e51ee upstream.

Our 32bit CP14/15 handling inherited some of the ARMv7 code for handling
the trapped system registers, completely missing the fact that the
fields for Rt and Rt2 are now 5 bit wide, and not 4...

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
---
 arch/arm64/kvm/sys_regs.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index d2650e8..c2489f6 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -1054,8 +1054,8 @@ static int kvm_handle_cp_64(struct kvm_vcpu *vcpu,
 {
 	struct sys_reg_params params;
 	u32 hsr = kvm_vcpu_get_hsr(vcpu);
-	int Rt = (hsr >> 5) & 0xf;
-	int Rt2 = (hsr >> 10) & 0xf;
+	int Rt = (hsr >> 5) & 0x1f;
+	int Rt2 = (hsr >> 10) & 0x1f;
 
 	params.is_aarch32 = true;
 	params.is_32bit = false;
@@ -1106,7 +1106,7 @@ static int kvm_handle_cp_32(struct kvm_vcpu *vcpu,
 {
 	struct sys_reg_params params;
 	u32 hsr = kvm_vcpu_get_hsr(vcpu);
-	int Rt  = (hsr >> 5) & 0xf;
+	int Rt  = (hsr >> 5) & 0x1f;
 
 	params.is_aarch32 = true;
 	params.is_32bit = true;
-- 
2.7.4


-- 
Jazz is not dead. It just smells funny.