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Date:   Wed, 25 Oct 2023 13:55:47 -0700
From:   Ira Weiny <ira.weiny@intel.com>
To:     Li Zhijian <lizhijian@fujitsu.com>, <alison.schofield@intel.com>,
        <vishal.l.verma@intel.com>, <ira.weiny@intel.com>,
        <bwidawsk@kernel.org>, <dan.j.williams@intel.com>,
        <linux-cxl@vger.kernel.org>
CC:     <dave.jiang@intel.com>, <Jonathan.Cameron@huawei.com>,
        <fan.ni@samsung.com>, <linux-kernel@vger.kernel.org>,
        Li Zhijian <lizhijian@fujitsu.com>
Subject: Re: [PATCH] cxl/region: Fix cxl_region_rwsem lock held when
 returning to user space
Message-ID: <653980d35bdb1_14ef4e294e1@iweiny-mobl.notmuch>
References: <20231025085450.2514906-1-lizhijian@fujitsu.com>
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Li Zhijian wrote:
> goto out to release cxl_region_rwsem. Fix below warning:
> ================================================
> WARNING: lock held when returning to user space!
> 6.6.0-rc3-lizhijian+ #213 Not tainted
> ------------------------------------------------
> cxl/673 is leaving the kernel with locks still held!
> 1 lock held by cxl/673:
>  #0: ffffffffa013b9d0 (cxl_region_rwsem){++++}-{3:3}, at: commit_store+0x7d/0x3e0 [cxl_core]
> 
> Fixes: d1257d098a5a ("cxl/region: Move cache invalidation before region teardown, and before setup")
> Signed-off-by: Li Zhijian <lizhijian@fujitsu.com>

Reviewed-by: Ira Weiny <ira.weiny@intel.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 6d63b8798c29..18da77f8f22b 100644
> --- a/drivers/cxl/core/region.c
> +++ b/drivers/cxl/core/region.c
> @@ -294,7 +294,7 @@ static ssize_t commit_store(struct device *dev, struct device_attribute *attr,
>  	 */
>  	rc = cxl_region_invalidate_memregion(cxlr);
>  	if (rc)
> -		return rc;
> +		goto out;
>  
>  	if (commit) {
>  		rc = cxl_region_decode_commit(cxlr);
> -- 
> 2.29.2
>