All of lore.kernel.org
 help / color / mirror / Atom feed
* [PATCH] kvm tools: fix boot of guests with more than 4gb of ram
@ 2013-06-24  1:23 Sasha Levin
  2013-06-24  9:05 ` Will Deacon
                   ` (2 more replies)
  0 siblings, 3 replies; 6+ messages in thread
From: Sasha Levin @ 2013-06-24  1:23 UTC (permalink / raw)
  To: penberg; +Cc: will.deacon, kvm, Sasha Levin

Commit "kvm tools: virtio: remove hardcoded assumptions
about guest page size" has introduced a bug that prevented
guests with more than 4gb of ram from booting.

The issue is that 'pfn' is a 32bit integer, so when multiplying
it by page size to get the actual page will cause an overflow if
the pfn referred to a memory area above 4gb.

Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
---
 tools/kvm/virtio/9p.c      | 2 +-
 tools/kvm/virtio/balloon.c | 2 +-
 tools/kvm/virtio/blk.c     | 2 +-
 tools/kvm/virtio/console.c | 2 +-
 tools/kvm/virtio/net.c     | 2 +-
 tools/kvm/virtio/rng.c     | 2 +-
 tools/kvm/virtio/scsi.c    | 2 +-
 7 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/tools/kvm/virtio/9p.c b/tools/kvm/virtio/9p.c
index b7a5723..033b638 100644
--- a/tools/kvm/virtio/9p.c
+++ b/tools/kvm/virtio/9p.c
@@ -1267,7 +1267,7 @@ static int init_vq(struct kvm *kvm, void *dev, u32 vq, u32 page_size, u32 align,
 
 	queue		= &p9dev->vqs[vq];
 	queue->pfn	= pfn;
-	p		= guest_flat_to_host(kvm, queue->pfn * page_size);
+	p		= guest_flat_to_host(kvm, (u64)queue->pfn * page_size);
 	job		= &p9dev->jobs[vq];
 
 	vring_init(&queue->vring, VIRTQUEUE_NUM, p, align);
diff --git a/tools/kvm/virtio/balloon.c b/tools/kvm/virtio/balloon.c
index d1b64fa..557ea25 100644
--- a/tools/kvm/virtio/balloon.c
+++ b/tools/kvm/virtio/balloon.c
@@ -204,7 +204,7 @@ static int init_vq(struct kvm *kvm, void *dev, u32 vq, u32 page_size, u32 align,
 
 	queue		= &bdev->vqs[vq];
 	queue->pfn	= pfn;
-	p		= guest_flat_to_host(kvm, queue->pfn * page_size);
+	p		= guest_flat_to_host(kvm, (u64)queue->pfn * page_size);
 
 	thread_pool__init_job(&bdev->jobs[vq], kvm, virtio_bln_do_io, queue);
 	vring_init(&queue->vring, VIRTIO_BLN_QUEUE_SIZE, p, align);
diff --git a/tools/kvm/virtio/blk.c b/tools/kvm/virtio/blk.c
index 44ac44b..c977353 100644
--- a/tools/kvm/virtio/blk.c
+++ b/tools/kvm/virtio/blk.c
@@ -167,7 +167,7 @@ static int init_vq(struct kvm *kvm, void *dev, u32 vq, u32 page_size, u32 align,
 
 	queue		= &bdev->vqs[vq];
 	queue->pfn	= pfn;
-	p		= guest_flat_to_host(kvm, queue->pfn * page_size);
+	p = guest_flat_to_host(kvm, (u64)queue->pfn * page_size);
 
 	vring_init(&queue->vring, VIRTIO_BLK_QUEUE_SIZE, p, align);
 
diff --git a/tools/kvm/virtio/console.c b/tools/kvm/virtio/console.c
index 1f88a4b..3ac4c9f 100644
--- a/tools/kvm/virtio/console.c
+++ b/tools/kvm/virtio/console.c
@@ -137,7 +137,7 @@ static int init_vq(struct kvm *kvm, void *dev, u32 vq, u32 page_size, u32 align,
 
 	queue		= &cdev.vqs[vq];
 	queue->pfn	= pfn;
-	p		= guest_flat_to_host(kvm, queue->pfn * page_size);
+	p		= guest_flat_to_host(kvm, (u64)queue->pfn * page_size);
 
 	vring_init(&queue->vring, VIRTIO_CONSOLE_QUEUE_SIZE, p, align);
 
diff --git a/tools/kvm/virtio/net.c b/tools/kvm/virtio/net.c
index 7855cfc..34a5f27 100644
--- a/tools/kvm/virtio/net.c
+++ b/tools/kvm/virtio/net.c
@@ -410,7 +410,7 @@ static int init_vq(struct kvm *kvm, void *dev, u32 vq, u32 page_size, u32 align,
 
 	queue		= &ndev->vqs[vq];
 	queue->pfn	= pfn;
-	p		= guest_flat_to_host(kvm, queue->pfn * page_size);
+	p		= guest_flat_to_host(kvm, (u64)queue->pfn * page_size);
 
 	vring_init(&queue->vring, VIRTIO_NET_QUEUE_SIZE, p, align);
 
diff --git a/tools/kvm/virtio/rng.c b/tools/kvm/virtio/rng.c
index 2ce8afd..d1754dc 100644
--- a/tools/kvm/virtio/rng.c
+++ b/tools/kvm/virtio/rng.c
@@ -98,7 +98,7 @@ static int init_vq(struct kvm *kvm, void *dev, u32 vq, u32 page_size, u32 align,
 
 	queue		= &rdev->vqs[vq];
 	queue->pfn	= pfn;
-	p		= guest_flat_to_host(kvm, queue->pfn * page_size);
+	p		= guest_flat_to_host(kvm, (u64)queue->pfn * page_size);
 
 	job = &rdev->jobs[vq];
 
diff --git a/tools/kvm/virtio/scsi.c b/tools/kvm/virtio/scsi.c
index 05b2dc6..ad6320d 100644
--- a/tools/kvm/virtio/scsi.c
+++ b/tools/kvm/virtio/scsi.c
@@ -63,7 +63,7 @@ static int init_vq(struct kvm *kvm, void *dev, u32 vq, u32 page_size, u32 align,
 
 	queue		= &sdev->vqs[vq];
 	queue->pfn	= pfn;
-	p		= guest_flat_to_host(kvm, queue->pfn * page_size);
+	p		= guest_flat_to_host(kvm, (u64)queue->pfn * page_size);
 
 	vring_init(&queue->vring, VIRTIO_SCSI_QUEUE_SIZE, p, align);
 
-- 
1.8.1.2


^ permalink raw reply related	[flat|nested] 6+ messages in thread
* Re: [PATCH] kvm tools: fix boot of guests with more than 4gb of ram
  2013-06-24  1:23 [PATCH] kvm tools: fix boot of guests with more than 4gb of ram Sasha Levin
@ 2013-06-24  9:05 ` Will Deacon
  2013-06-24 10:06 ` Michael Tokarev
  2013-06-25  0:58 ` Michael Ellerman
  2 siblings, 0 replies; 6+ messages in thread
From: Will Deacon @ 2013-06-24  9:05 UTC (permalink / raw)
  To: Sasha Levin; +Cc: penberg, kvm

On Mon, Jun 24, 2013 at 02:23:31AM +0100, Sasha Levin wrote:
> Commit "kvm tools: virtio: remove hardcoded assumptions
> about guest page size" has introduced a bug that prevented
> guests with more than 4gb of ram from booting.

4GB of memory?!?! ;)

> The issue is that 'pfn' is a 32bit integer, so when multiplying
> it by page size to get the actual page will cause an overflow if
> the pfn referred to a memory area above 4gb.
> 
> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>

Acked-by: Will Deacon <will.deacon@arm.com>

Will

^ permalink raw reply	[flat|nested] 6+ messages in thread
* Re: [PATCH] kvm tools: fix boot of guests with more than 4gb of ram
  2013-06-24  1:23 [PATCH] kvm tools: fix boot of guests with more than 4gb of ram Sasha Levin
  2013-06-24  9:05 ` Will Deacon
@ 2013-06-24 10:06 ` Michael Tokarev
  2013-07-07 15:29   ` Pekka Enberg
  2013-06-25  0:58 ` Michael Ellerman
  2 siblings, 1 reply; 6+ messages in thread
From: Michael Tokarev @ 2013-06-24 10:06 UTC (permalink / raw)
  To: Sasha Levin; +Cc: penberg, will.deacon, kvm

24.06.2013 05:23, Sasha Levin wrote:
>  	queue		= &p9dev->vqs[vq];
>  	queue->pfn	= pfn;
> -	p		= guest_flat_to_host(kvm, queue->pfn * page_size);
> +	p		= guest_flat_to_host(kvm, (u64)queue->pfn * page_size);

Maybe it's worth to use a common function for this,
something like guest_queue_to_host(kvm, queue) ?

Thanks,

/mjt

^ permalink raw reply	[flat|nested] 6+ messages in thread
* Re: [PATCH] kvm tools: fix boot of guests with more than 4gb of ram
  2013-06-24  1:23 [PATCH] kvm tools: fix boot of guests with more than 4gb of ram Sasha Levin
  2013-06-24  9:05 ` Will Deacon
  2013-06-24 10:06 ` Michael Tokarev
@ 2013-06-25  0:58 ` Michael Ellerman
  2013-06-25 17:02   ` Sasha Levin
  2 siblings, 1 reply; 6+ messages in thread
From: Michael Ellerman @ 2013-06-25  0:58 UTC (permalink / raw)
  To: Sasha Levin; +Cc: penberg, will.deacon, kvm

On Sun, 2013-06-23 at 21:23 -0400, Sasha Levin wrote:
> Commit "kvm tools: virtio: remove hardcoded assumptions
> about guest page size" has introduced a bug that prevented
> guests with more than 4gb of ram from booting.
> 
> The issue is that 'pfn' is a 32bit integer, so when multiplying
> it by page size to get the actual page will cause an overflow if
> the pfn referred to a memory area above 4gb.

Couldn't we just make pfn 64 bit?

cheers


^ permalink raw reply	[flat|nested] 6+ messages in thread
* Re: [PATCH] kvm tools: fix boot of guests with more than 4gb of ram
  2013-06-25  0:58 ` Michael Ellerman
@ 2013-06-25 17:02   ` Sasha Levin
  0 siblings, 0 replies; 6+ messages in thread
From: Sasha Levin @ 2013-06-25 17:02 UTC (permalink / raw)
  To: Michael Ellerman; +Cc: penberg, will.deacon, kvm

On 06/24/2013 08:58 PM, Michael Ellerman wrote:
> On Sun, 2013-06-23 at 21:23 -0400, Sasha Levin wrote:
>> Commit "kvm tools: virtio: remove hardcoded assumptions
>> about guest page size" has introduced a bug that prevented
>> guests with more than 4gb of ram from booting.
>>
>> The issue is that 'pfn' is a 32bit integer, so when multiplying
>> it by page size to get the actual page will cause an overflow if
>> the pfn referred to a memory area above 4gb.
>
> Couldn't we just make pfn 64 bit?

pfn is passed to us by the guest virtio driver, and is 32 bit.


Thanks,
Sasha


^ permalink raw reply	[flat|nested] 6+ messages in thread
* Re: [PATCH] kvm tools: fix boot of guests with more than 4gb of ram
  2013-06-24 10:06 ` Michael Tokarev
@ 2013-07-07 15:29   ` Pekka Enberg
  0 siblings, 0 replies; 6+ messages in thread
From: Pekka Enberg @ 2013-07-07 15:29 UTC (permalink / raw)
  To: Michael Tokarev; +Cc: Sasha Levin, Will Deacon, KVM General

On Mon, Jun 24, 2013 at 1:06 PM, Michael Tokarev <mjt@tls.msk.ru> wrote:
> 24.06.2013 05:23, Sasha Levin wrote:
>>       queue           = &p9dev->vqs[vq];
>>       queue->pfn      = pfn;
>> -     p               = guest_flat_to_host(kvm, queue->pfn * page_size);
>> +     p               = guest_flat_to_host(kvm, (u64)queue->pfn * page_size);
>
> Maybe it's worth to use a common function for this,
> something like guest_queue_to_host(kvm, queue) ?

Sasha, care to do something like this and resend the patch?

^ permalink raw reply	[flat|nested] 6+ messages in thread
end of thread, other threads:[~2013-07-07 15:29 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2013-06-24  1:23 [PATCH] kvm tools: fix boot of guests with more than 4gb of ram Sasha Levin
2013-06-24  9:05 ` Will Deacon
2013-06-24 10:06 ` Michael Tokarev
2013-07-07 15:29   ` Pekka Enberg
2013-06-25  0:58 ` Michael Ellerman
2013-06-25 17:02   ` Sasha Levin

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.