| Message ID | 1372037011-19466-1-git-send-email-sasha.levin@oracle.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
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 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
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 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
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 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
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 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
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? -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
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);
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(-)