diff mbox

linux-next: manual merge of the kvm-arm tree with Linus' tree

Message ID 87mwbpiv0z.fsf@approximate.cambridge.arm.com
State Accepted
Commit fb3ec67942e92e5713e05b7691b277d0a0c0575d
Headers show

Commit Message

Marc Zyngier July 31, 2014, 12:15 p.m. UTC 
On Thu, Jul 31 2014 at 12:53:03 pm BST, Christoffer Dall <christofferdall@christofferdall.dk> wrote:

Hi Christoffer,

> On Thu, Jul 31, 2014 at 8:30 AM, Stephen Rothwell <sfr@canb.auug.org.au> wrote:
>
>     Hi all,
>    
>     Today's linux-next merge of the kvm-arm tree got a conflict in
>     virt/kvm/arm/vgic.c between commit 63afbe7a0ac1 ("kvm: arm64: vgic: fix
>     hyp panic with 64k pages on juno platform") from Linus' tree and commit
>     8f186d522c69 ("KVM: ARM: vgic: split GICv2 backend from the main vgic
>     code") and others from the kvm-arm tree.
>    
>     I fixed it up (the latter extensively rewrites the function, so I just
>     used that) and can carry the fix as necessary (no action is required).
>
> Hmm that doesn't look correct, the checks  for
> PAGE_ALIGNED(vcpu_res.start) and PAGE_ALIGNED(resource_size(vcpu_res))
> still need to be enforced for both vgic-v2 and vgic-v3.  How do we
> provide a correct fix for Linux-next?

I've provided a resolution for GICv2 in a separate email. For GICv3, I
have the following patch in my tree, which can be added at a later time.

Thanks,

	M.

From 3eedf1d172230a117ec90832748879e88d9c3471 Mon Sep 17 00:00:00 2001
From: Marc Zyngier <marc.zyngier@arm.com>
Date: Thu, 31 Jul 2014 11:42:18 +0100
Subject: [PATCH] KVM: arm64: GICv3: mandate page-aligned GICV region

Just like GICv2 was fixed in 63afbe7a0ac1
(kvm: arm64: vgic: fix hyp panic with 64k pages on juno platform),
mandate the GICV region to be both aligned on a page boundary and
its size to be a multiple of page size.

This prevents a guest from being able to poke at regions where we
have no idea what is sitting there.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
---
 virt/kvm/arm/vgic-v3.c | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

Comments

Christoffer Dall July 31, 2014, 2:23 p.m. UTC | #1 
On Thu, Jul 31, 2014 at 01:15:40PM +0100, Marc Zyngier wrote:
> On Thu, Jul 31 2014 at 12:53:03 pm BST, Christoffer Dall <christofferdall@christofferdall.dk> wrote:
> 
> Hi Christoffer,
> 
> > On Thu, Jul 31, 2014 at 8:30 AM, Stephen Rothwell <sfr@canb.auug.org.au> wrote:
> >
> >     Hi all,
> >    
> >     Today's linux-next merge of the kvm-arm tree got a conflict in
> >     virt/kvm/arm/vgic.c between commit 63afbe7a0ac1 ("kvm: arm64: vgic: fix
> >     hyp panic with 64k pages on juno platform") from Linus' tree and commit
> >     8f186d522c69 ("KVM: ARM: vgic: split GICv2 backend from the main vgic
> >     code") and others from the kvm-arm tree.
> >    
> >     I fixed it up (the latter extensively rewrites the function, so I just
> >     used that) and can carry the fix as necessary (no action is required).
> >
> > Hmm that doesn't look correct, the checks  for
> > PAGE_ALIGNED(vcpu_res.start) and PAGE_ALIGNED(resource_size(vcpu_res))
> > still need to be enforced for both vgic-v2 and vgic-v3.  How do we
> > provide a correct fix for Linux-next?
> 
> I've provided a resolution for GICv2 in a separate email. For GICv3, I
> have the following patch in my tree, which can be added at a later time.
> 
The GICv3 build fix and the GICv3 fix you provided here are now both in
kvmarm/next.

Stephen, did you pick up the resolution provided by Marc for the gicv2
fix patch so that it applies to tomorrow's next/kvmarm merge?

Thanks,
-Christoffer
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/
Marc Zyngier July 31, 2014, 2:30 p.m. UTC | #2 
On Thu, Jul 31 2014 at 03:23:47 PM, Christoffer Dall <cdall@cs.columbia.edu> wrote:
> On Thu, Jul 31, 2014 at 01:15:40PM +0100, Marc Zyngier wrote:
>> On Thu, Jul 31 2014 at 12:53:03 pm BST, Christoffer Dall
>> <christofferdall@christofferdall.dk> wrote:
>> 
>> Hi Christoffer,
>> 
>> > On Thu, Jul 31, 2014 at 8:30 AM, Stephen Rothwell
>> > <sfr@canb.auug.org.au> wrote:
>> >
>> >     Hi all,
>> >    
>> >     Today's linux-next merge of the kvm-arm tree got a conflict in
>> >     virt/kvm/arm/vgic.c between commit 63afbe7a0ac1 ("kvm: arm64: vgic: fix
>> >     hyp panic with 64k pages on juno platform") from Linus' tree and commit
>> >     8f186d522c69 ("KVM: ARM: vgic: split GICv2 backend from the main vgic
>> >     code") and others from the kvm-arm tree.
>> >    
>> >     I fixed it up (the latter extensively rewrites the function, so I just
>> >     used that) and can carry the fix as necessary (no action is required).
>> >
>> > Hmm that doesn't look correct, the checks  for
>> > PAGE_ALIGNED(vcpu_res.start) and PAGE_ALIGNED(resource_size(vcpu_res))
>> > still need to be enforced for both vgic-v2 and vgic-v3.  How do we
>> > provide a correct fix for Linux-next?
>> 
>> I've provided a resolution for GICv2 in a separate email. For GICv3, I
>> have the following patch in my tree, which can be added at a later time.
>> 
> The GICv3 build fix and the GICv3 fix you provided here are now both
> in kvmarm/next.

Excellent, thanks Christoffer.

Cheers,

	M.
Stephen Rothwell Aug. 1, 2014, 5:21 a.m. UTC | #3 
Hi Christoffer,

On Thu, 31 Jul 2014 16:23:47 +0200 Christoffer Dall <cdall@cs.columbia.edu> wrote:
>
> Stephen, did you pick up the resolution provided by Marc for the gicv2
> fix patch so that it applies to tomorrow's next/kvmarm merge?

Yes, I have.  You will need to produce the same for Linus eventually,
or do the merge yourself as I suggested.
diff mbox

Patch

diff --git a/virt/kvm/arm/vgic-v3.c b/virt/kvm/arm/vgic-v3.c
index f01d446..1c2c8ee 100644
--- a/virt/kvm/arm/vgic-v3.c
+++ b/virt/kvm/arm/vgic-v3.c
@@ -215,6 +215,22 @@  int vgic_v3_probe(struct device_node *vgic_node,
 		ret = -ENXIO;
 		goto out;
 	}
+
+	if (!PAGE_ALIGNED(vcpu_res.start)) {
+		kvm_err("GICV physical address 0x%llx not page aligned\n",
+			(unsigned long long)vcpu_res.start);
+		ret = -ENXIO;
+		goto out;
+	}
+
+	if (!PAGE_ALIGNED(resource_size(&vcpu_res))) {
+		kvm_err("GICV size 0x%llx not a multiple of page size 0x%lx\n",
+			(unsigned long long)resource_size(&vcpu_res),
+			PAGE_SIZE);
+		ret = -ENXIO;
+		goto out;
+	}
+
 	vgic->vcpu_base = vcpu_res.start;
 	vgic->vctrl_base = NULL;
 	vgic->type = VGIC_V3;