linux-kernel - Re: [PATCH vhost 2/2] vdpa/mlx5: Fix suboptimal range on iotlb iteration

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20241113013149-mutt-send-email-mst@kernel.org>
Date: Wed, 13 Nov 2024 01:32:10 -0500
From: "Michael S. Tsirkin" <mst@...hat.com>
To: Dragos Tatulea <dtatulea@...dia.com>
Cc: virtualization@...ts.linux.dev, Si-Wei Liu <si-wei.liu@...cle.com>,
	Jason Wang <jasowang@...hat.com>,
	Eugenio Perez Martin <eperezma@...hat.com>, kvm@...r.kernel.org,
	linux-kernel@...r.kernel.org, Gal Pressman <gal@...dia.com>,
	Parav Pandit <parav@...dia.com>,
	Xuan Zhuo <xuanzhuo@...ux.alibaba.com>
Subject: Re: [PATCH vhost 2/2] vdpa/mlx5: Fix suboptimal range on iotlb
 iteration

On Mon, Oct 21, 2024 at 04:40:40PM +0300, Dragos Tatulea wrote:
> From: Si-Wei Liu <si-wei.liu@...cle.com>
> 
> The starting iova address to iterate iotlb map entry within a range
> was set to an irrelevant value when passing to the itree_next()
> iterator, although luckily it doesn't affect the outcome of finding
> out the granule of the smallest iotlb map size. Fix the code to make
> it consistent with the following for-loop.
> 
> Fixes: 94abbccdf291 ("vdpa/mlx5: Add shared memory registration code")


But the cover letter says "that's why it does not have a fixes tag".
Confused.

> Signed-off-by: Si-Wei Liu <si-wei.liu@...cle.com>
> Signed-off-by: Dragos Tatulea <dtatulea@...dia.com>
> ---
>  drivers/vdpa/mlx5/core/mr.c | 4 +---
>  1 file changed, 1 insertion(+), 3 deletions(-)
> 
> diff --git a/drivers/vdpa/mlx5/core/mr.c b/drivers/vdpa/mlx5/core/mr.c
> index 7d0c83b5b071..8455f08f5d40 100644
> --- a/drivers/vdpa/mlx5/core/mr.c
> +++ b/drivers/vdpa/mlx5/core/mr.c
> @@ -368,7 +368,6 @@ static int map_direct_mr(struct mlx5_vdpa_dev *mvdev, struct mlx5_vdpa_direct_mr
>  	unsigned long lgcd = 0;
>  	int log_entity_size;
>  	unsigned long size;
> -	u64 start = 0;
>  	int err;
>  	struct page *pg;
>  	unsigned int nsg;
> @@ -379,10 +378,9 @@ static int map_direct_mr(struct mlx5_vdpa_dev *mvdev, struct mlx5_vdpa_direct_mr
>  	struct device *dma = mvdev->vdev.dma_dev;
>  
>  	for (map = vhost_iotlb_itree_first(iotlb, mr->start, mr->end - 1);
> -	     map; map = vhost_iotlb_itree_next(map, start, mr->end - 1)) {
> +	     map; map = vhost_iotlb_itree_next(map, mr->start, mr->end - 1)) {
>  		size = maplen(map, mr);
>  		lgcd = gcd(lgcd, size);
> -		start += size;
>  	}
>  	log_entity_size = ilog2(lgcd);
>  
> -- 
> 2.46.1