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Message-ID: <b236e0d4-b8ab-49ca-99f3-364ea41cff49@intel.com>
Date:   Mon, 20 Nov 2023 08:40:13 -0700
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Subject: Re: [PATCH 1/2] cxl/cdat: Handle cdat table build errors
To:     Ira Weiny <ira.weiny@intel.com>,
        Jonathan Cameron <jonathan.cameron@huawei.com>,
        Fan Ni <nifan.cxl@gmail.com>
CC:     <linux-cxl@vger.kernel.org>, <linux-kernel@vger.kernel.org>
References: <20231117-fix-cdat-cs-v1-0-ffc2b116ca6c@intel.com>
 <20231117-fix-cdat-cs-v1-1-ffc2b116ca6c@intel.com>
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From:   Dave Jiang <dave.jiang@intel.com>
In-Reply-To: <20231117-fix-cdat-cs-v1-1-ffc2b116ca6c@intel.com>
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On 11/17/23 18:14, Ira Weiny wrote:
> The callback for building CDAT tables may return negative error codes.
> This was previously unhandled and will result in potentially huge
> allocations later on in ct3_build_cdat()
> 
> Detect the negative error code and defer cdat building.
> 
> Signed-off-by: Ira Weiny <ira.weiny@intel.com>

Reviewed-by: Dave Jiang <dave.jiang@intel.com>
> 
> ---
> This likely needs to have some more robust error handling in the event
> of errors.  But this at least prevents more errors down the line with
> invalid allocations.
> ---
>  hw/cxl/cxl-cdat.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/hw/cxl/cxl-cdat.c b/hw/cxl/cxl-cdat.c
> index 639a2db3e17b..24829cf2428d 100644
> --- a/hw/cxl/cxl-cdat.c
> +++ b/hw/cxl/cxl-cdat.c
> @@ -63,7 +63,7 @@ static void ct3_build_cdat(CDATObject *cdat, Error **errp)
>      cdat->built_buf_len = cdat->build_cdat_table(&cdat->built_buf,
>                                                   cdat->private);
>  
> -    if (!cdat->built_buf_len) {
> +    if (cdat->built_buf_len <= 0) {
>          /* Build later as not all data available yet */
>          cdat->to_update = true;
>          return;
>