Re: [PATCH] vhost: fix offset while mmaping log base address

[Chenbo Xia <chenbox@nvidia.com>]

> On Jul 8, 2024, at 14:57, BillXiang <xiangwencheng@dayudpu.com> wrote:
> 
> External email: Use caution opening links or attachments
> 
> 
> From: BillXiang <xiangwencheng@dayudpu.com>
> 
> For sanity the offset should be the last parameter of mmap.
> 
> Fixes: fbc4d24 ("vhost: fix offset while mmaping log base address")

The commit id length should be 12.

Since QEMU always send offset 0, I think it’s no need to backport the
patch, so no cc-stable is fine.

With above fixed:

Reviewed-by: Chenbo Xia <chenbox@nvidia.com>

> Signed-off-by: BillXiang <xiangwencheng@dayudpu.com>
> ---
> lib/vhost/vhost_user.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/lib/vhost/vhost_user.c b/lib/vhost/vhost_user.c
> index 5f470da38a..0893ae80bb 100644
> --- a/lib/vhost/vhost_user.c
> +++ b/lib/vhost/vhost_user.c
> @@ -2399,7 +2399,7 @@ vhost_user_set_log_base(struct virtio_net **pdev,
>         * mmap from 0 to workaround a hugepage mmap bug: mmap will
>         * fail when offset is not page size aligned.
>         */
> -       addr = mmap(0, size + off, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
> +       addr = mmap(0, size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, off);
>        alignment = get_blk_size(fd);
>        close(fd);
>        if (addr == MAP_FAILED) {
> --
> 2.30.0