diff mbox

[dpdk-dev,v2] net/virtio-user: fix not working on 32-bit system

Message ID 1492569033-140348-1-git-send-email-jianfeng.tan@intel.com (mailing list archive)
State Accepted, archived
Delegated to: Yuanhan Liu
Headers

Checks

Context Check Description
ci/checkpatch success coding style OK
ci/Intel-compilation success Compilation OK

Commit Message

Jianfeng Tan April 19, 2017, 2:30 a.m. UTC 
  virtio-user cannot work on 32-bit system as higher 32-bit of the
addr field (64-bit) in the desc is filled with non-zero value
which should not happen for a 32-bit system.

In case of virtio-user, we use buf_addr of mbuf to fill the
virtqueue desc addr. This is a regression bug. For 32-bit system,
the first 4 bytes of mbuf is buf_addr, with following 8 bytes for
buf_phyaddr. With below wrong definition, both buf_addr and lower
4 bytes buf_phyaddr are obtained to fill the virtqueue desc.
  #define VIRTIO_MBUF_ADDR(mb, vq) \
	(*(uint64_t *)((uintptr_t)(mb) + (vq)->offset))

Fixes: 25f80d108780 ("net/virtio: fix packet corruption")
Cc: stable@dpdk.org

Signed-off-by: Jianfeng Tan <jianfeng.tan@intel.com>
---
 drivers/net/virtio/virtqueue.h | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

Comments

Yuanhan Liu April 19, 2017, 5:53 a.m. UTC | #1 
On Wed, Apr 19, 2017 at 02:30:33AM +0000, Jianfeng Tan wrote:
> virtio-user cannot work on 32-bit system as higher 32-bit of the
> addr field (64-bit) in the desc is filled with non-zero value
> which should not happen for a 32-bit system.
> 
> In case of virtio-user, we use buf_addr of mbuf to fill the
> virtqueue desc addr. This is a regression bug. For 32-bit system,
> the first 4 bytes of mbuf is buf_addr, with following 8 bytes for
> buf_phyaddr. With below wrong definition, both buf_addr and lower
> 4 bytes buf_phyaddr are obtained to fill the virtqueue desc.
>   #define VIRTIO_MBUF_ADDR(mb, vq) \
> 	(*(uint64_t *)((uintptr_t)(mb) + (vq)->offset))
> 
> Fixes: 25f80d108780 ("net/virtio: fix packet corruption")
> Cc: stable@dpdk.org
> 
> Signed-off-by: Jianfeng Tan <jianfeng.tan@intel.com>
> ---
>  drivers/net/virtio/virtqueue.h | 12 +++++++++---
>  1 file changed, 9 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/net/virtio/virtqueue.h b/drivers/net/virtio/virtqueue.h
> index f9e3736..2e67460 100644
> --- a/drivers/net/virtio/virtqueue.h
> +++ b/drivers/net/virtio/virtqueue.h
> @@ -69,10 +69,16 @@ struct rte_mbuf;
>  
>  #ifdef RTE_VIRTIO_USER
>  /**
> - * Return the physical address (or virtual address in case of
> - * virtio-user) of mbuf data buffer.
> + *
> + * Return the physical address of mbuf data buffer for virtio pci:
> + *  on 32-bit system, offset equals 4, return the second four bytes of mbuf;
> + *  on 64-bit system, offset equals 8, return the second eight bytes of mbuf.
> + * Return the virtual address of mbuf data buffer for virtio-user.
> + *  on 32-bit system, offset equals 0, return the first four bytes of mbuf;
> + *  on 64-bit system, offset equals 0, return the first eight bytes of mbuf;


I've expected it to be plain english, something like following:

    /*
     * Return the physical address (or virtual address in case of
     * virtio-user) of mbuf data buffer.
     *
     * The address is firstly casted to the word size (sizeof(uintptr_t))
     * before casting it to uint64_t. This is to make it work with different
     * combination of word size (64 bit and 32 bit) and virtio device
     * (virtio-pci and virtio-user).
     */

Okay to you?

	--yliu
Jianfeng Tan April 19, 2017, 6:21 a.m. UTC | #2 
> -----Original Message-----
> From: Yuanhan Liu [mailto:yuanhan.liu@linux.intel.com]
> Sent: Wednesday, April 19, 2017 1:54 PM
> To: Tan, Jianfeng
> Cc: dev@dpdk.org; olivier.matz@6wind.com; stable@dpdk.org
> Subject: Re: [PATCH v2] net/virtio-user: fix not working on 32-bit system
> 
> On Wed, Apr 19, 2017 at 02:30:33AM +0000, Jianfeng Tan wrote:
> > virtio-user cannot work on 32-bit system as higher 32-bit of the
> > addr field (64-bit) in the desc is filled with non-zero value
> > which should not happen for a 32-bit system.
> >
> > In case of virtio-user, we use buf_addr of mbuf to fill the
> > virtqueue desc addr. This is a regression bug. For 32-bit system,
> > the first 4 bytes of mbuf is buf_addr, with following 8 bytes for
> > buf_phyaddr. With below wrong definition, both buf_addr and lower
> > 4 bytes buf_phyaddr are obtained to fill the virtqueue desc.
> >   #define VIRTIO_MBUF_ADDR(mb, vq) \
> > 	(*(uint64_t *)((uintptr_t)(mb) + (vq)->offset))
> >
> > Fixes: 25f80d108780 ("net/virtio: fix packet corruption")
> > Cc: stable@dpdk.org
> >
> > Signed-off-by: Jianfeng Tan <jianfeng.tan@intel.com>
> > ---
> >  drivers/net/virtio/virtqueue.h | 12 +++++++++---
> >  1 file changed, 9 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/net/virtio/virtqueue.h b/drivers/net/virtio/virtqueue.h
> > index f9e3736..2e67460 100644
> > --- a/drivers/net/virtio/virtqueue.h
> > +++ b/drivers/net/virtio/virtqueue.h
> > @@ -69,10 +69,16 @@ struct rte_mbuf;
> >
> >  #ifdef RTE_VIRTIO_USER
> >  /**
> > - * Return the physical address (or virtual address in case of
> > - * virtio-user) of mbuf data buffer.
> > + *
> > + * Return the physical address of mbuf data buffer for virtio pci:
> > + *  on 32-bit system, offset equals 4, return the second four bytes of mbuf;
> > + *  on 64-bit system, offset equals 8, return the second eight bytes of
> mbuf.
> > + * Return the virtual address of mbuf data buffer for virtio-user.
> > + *  on 32-bit system, offset equals 0, return the first four bytes of mbuf;
> > + *  on 64-bit system, offset equals 0, return the first eight bytes of mbuf;
> 
> 
> I've expected it to be plain english, something like following:
> 
>     /*
>      * Return the physical address (or virtual address in case of
>      * virtio-user) of mbuf data buffer.
>      *
>      * The address is firstly casted to the word size (sizeof(uintptr_t))
>      * before casting it to uint64_t. This is to make it work with different
>      * combination of word size (64 bit and 32 bit) and virtio device
>      * (virtio-pci and virtio-user).
>      */
> 
> Okay to you?

Yep, sounds better. Thanks!
Yuanhan Liu April 19, 2017, 6:24 a.m. UTC | #3 
On Wed, Apr 19, 2017 at 06:21:59AM +0000, Tan, Jianfeng wrote:
> 
> 
> > I've expected it to be plain english, something like following:
> > 
> >     /*
> >      * Return the physical address (or virtual address in case of
> >      * virtio-user) of mbuf data buffer.
> >      *
> >      * The address is firstly casted to the word size (sizeof(uintptr_t))
> >      * before casting it to uint64_t. This is to make it work with different
> >      * combination of word size (64 bit and 32 bit) and virtio device
> >      * (virtio-pci and virtio-user).
> >      */
> > 
> > Okay to you?
> 
> Yep, sounds better. Thanks!

Good. Applied to dpdk-next-virtio, with above change.

Thanks.

	--yliu
diff mbox

Patch

diff --git a/drivers/net/virtio/virtqueue.h b/drivers/net/virtio/virtqueue.h
index f9e3736..2e67460 100644
--- a/drivers/net/virtio/virtqueue.h
+++ b/drivers/net/virtio/virtqueue.h
@@ -69,10 +69,16 @@  struct rte_mbuf;
 
 #ifdef RTE_VIRTIO_USER
 /**
- * Return the physical address (or virtual address in case of
- * virtio-user) of mbuf data buffer.
+ *
+ * Return the physical address of mbuf data buffer for virtio pci:
+ *  on 32-bit system, offset equals 4, return the second four bytes of mbuf;
+ *  on 64-bit system, offset equals 8, return the second eight bytes of mbuf.
+ * Return the virtual address of mbuf data buffer for virtio-user.
+ *  on 32-bit system, offset equals 0, return the first four bytes of mbuf;
+ *  on 64-bit system, offset equals 0, return the first eight bytes of mbuf;
  */
-#define VIRTIO_MBUF_ADDR(mb, vq) (*(uint64_t *)((uintptr_t)(mb) + (vq)->offset))
+#define VIRTIO_MBUF_ADDR(mb, vq) \
+	((uint64_t)(*(uintptr_t *)((uintptr_t)(mb) + (vq)->offset)))
 #else
 #define VIRTIO_MBUF_ADDR(mb, vq) ((mb)->buf_physaddr)
 #endif