From: Maxime Coquelin <maxime.coquelin@redhat.com>
To: David Marchand <david.marchand@redhat.com>,
dev@dpdk.org, roy.fan.zhang@intel.com,
Chenbo Xia <chenbo.xia@intel.com>,
Christophe Fontaine <cfontain@redhat.com>
Subject: Re: [PATCH v2] vhost: fix external message handlers
Date: Tue, 8 Mar 2022 11:44:37 +0100 [thread overview]
Message-ID: <0272a7ca-aac5-b029-061a-3910d6f49548@redhat.com> (raw)
In-Reply-To: <20220308094422.25685-1-david.marchand@redhat.com>
On 3/8/22 10:44, David Marchand wrote:
> Following a rework, external message handlers were receiving a pointer
> to a vhost_user message (as stated in the API), but lost the ability to
> interact with fds attached to the message.
> Restore the original layout and put a build check and reminders.
>
> Bugzilla ID: 953
> Fixes: 5e0099dc709e ("vhost: remove payload size limitation")
>
> Reported-by: Fan Zhang <roy.fan.zhang@intel.com>
> Signed-off-by: David Marchand <david.marchand@redhat.com>
> ---
> Changes since v1:
> - fixed build with clang,
>
> ---
> lib/vhost/vhost_user.c | 8 ++++----
> lib/vhost/vhost_user.h | 7 +++++--
> 2 files changed, 9 insertions(+), 6 deletions(-)
>
> diff --git a/lib/vhost/vhost_user.c b/lib/vhost/vhost_user.c
> index 723c6890c3..589b950458 100644
> --- a/lib/vhost/vhost_user.c
> +++ b/lib/vhost/vhost_user.c
> @@ -3023,8 +3023,8 @@ vhost_user_msg_handler(int vid, int fd)
>
> handled = false;
> if (dev->extern_ops.pre_msg_handle) {
> - ret = (*dev->extern_ops.pre_msg_handle)(dev->vid,
> - (void *)&ctx.msg);
> + RTE_BUILD_BUG_ON(offsetof(struct vhu_msg_context, msg) != 0);
> + ret = (*dev->extern_ops.pre_msg_handle)(dev->vid, &ctx);
> switch (ret) {
> case RTE_VHOST_MSG_RESULT_REPLY:
> send_vhost_reply(dev, fd, &ctx);
> @@ -3069,8 +3069,8 @@ vhost_user_msg_handler(int vid, int fd)
> skip_to_post_handle:
> if (ret != RTE_VHOST_MSG_RESULT_ERR &&
> dev->extern_ops.post_msg_handle) {
> - ret = (*dev->extern_ops.post_msg_handle)(dev->vid,
> - (void *)&ctx.msg);
> + RTE_BUILD_BUG_ON(offsetof(struct vhu_msg_context, msg) != 0);
> + ret = (*dev->extern_ops.post_msg_handle)(dev->vid, &ctx);
> switch (ret) {
> case RTE_VHOST_MSG_RESULT_REPLY:
> send_vhost_reply(dev, fd, &ctx);
> diff --git a/lib/vhost/vhost_user.h b/lib/vhost/vhost_user.h
> index be53669f3b..c946cc2ef4 100644
> --- a/lib/vhost/vhost_user.h
> +++ b/lib/vhost/vhost_user.h
> @@ -152,10 +152,13 @@ typedef struct VhostUserMsg {
> /* Nothing should be added after the payload */
> } __rte_packed VhostUserMsg;
>
> -struct vhu_msg_context {
> +/* Note: this structure and VhostUserMsg can't be changed carelessly as
> + * external message handlers rely on them.
> + */
> +struct __rte_packed vhu_msg_context {
> + VhostUserMsg msg;
> int fds[VHOST_MEMORY_MAX_NREGIONS];
> int fd_num;
> - VhostUserMsg msg;
> };
>
> #define VHOST_USER_HDR_SIZE offsetof(VhostUserMsg, payload.u64)
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Thanks,
Maxime
next prev parent reply other threads:[~2022-03-08 10:44 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-03-07 18:11 [PATCH] " David Marchand
2022-03-08 8:34 ` Maxime Coquelin
2022-03-08 8:37 ` David Marchand
2022-03-08 8:39 ` Maxime Coquelin
2022-03-08 9:44 ` [PATCH v2] " David Marchand
2022-03-08 10:44 ` Maxime Coquelin [this message]
2022-03-08 14:04 ` Poczatek, Jakub
2022-03-08 14:47 ` Christophe Fontaine
2022-03-08 15:06 ` David Marchand
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