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Date:   Mon, 7 Nov 2022 15:40:36 -0800
From:   Dan Williams <dan.j.williams@intel.com>
To:     Fan Ni <fan.ni@samsung.com>,
        "alison.schofield@intel.com" <alison.schofield@intel.com>,
        "vishal.l.verma@intel.com" <vishal.l.verma@intel.com>,
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CC:     "linux-cxl@vger.kernel.org" <linux-cxl@vger.kernel.org>,
        Adam Manzanares <a.manzanares@samsung.com>,
        "dave@stgolabs.net" <dave@stgolabs.net>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Fan Ni <fan.ni@samsung.com>
Subject: RE: [PATCH] cxl/region: Fix memdev reuse check
Message-ID: <63699774d1af_18432294b8@dwillia2-xfh.jf.intel.com.notmuch>
References: <CGME20221107212232uscas1p20a000834b76db7a7e459708b06638120@uscas1p2.samsung.com>
 <20221107212153.745993-1-fan.ni@samsung.com>
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Fan Ni wrote:
> Memdev reuse in a region currently does not iterate over all of the
> interleave targets. Fix this by using existing iterator for memdev reuse
> check.

Not enough detail, what does this actually fix in practice? For example,
if an end user encountered this bug, what would they see as the
symptoms?  I could probably figure out, but for bugs I should not have
to, and more importantly downstream OSV kernel maintainers, who do not
have the same context as CXL developers, also need that information to
decide if this is a fix they want to backport into their kernel.

> 
> Fixes: 384e624bb211 ("cxl/region: Attach endpoint decoders")
> Signed-off-by: Fan Ni <fan.ni@samsung.com>
> ---
>  drivers/cxl/core/region.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c
> index f9ae5ad284ff..c7152b4bd9eb 100644
> --- a/drivers/cxl/core/region.c
> +++ b/drivers/cxl/core/region.c
> @@ -1226,7 +1226,7 @@ static int cxl_region_attach(struct cxl_region *cxlr,
>  		struct cxl_endpoint_decoder *cxled_target;
>  		struct cxl_memdev *cxlmd_target;
>  
> -		cxled_target = p->targets[pos];
> +		cxled_target = p->targets[i];
>  		if (!cxled_target)
>  			continue;
>  
> -- 
> 2.25.1