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Subject: Re: [PATCH] f2fs: don't put dentry page in pagecache into highmem
To:     Yunlong Song <yunlong.song@huawei.com>, <jaegeuk@kernel.org>,
        <chao@kernel.org>, <yunlong.song@icloud.com>
CC:     <miaoxie@huawei.com>, <bintian.wang@huawei.com>,
        <shengyong1@huawei.com>, <heyunlei@huawei.com>,
        <linux-f2fs-devel@lists.sourceforge.net>,
        <linux-kernel@vger.kernel.org>
References: <1519821112-137593-1-git-send-email-yunlong.song@huawei.com>
From:   Chao Yu <yuchao0@huawei.com>
Message-ID: <dcb20f79-0107-661c-0dec-9251f799ae44@huawei.com>
Date:   Thu, 1 Mar 2018 09:20:56 +0800
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On 2018/2/28 20:31, Yunlong Song wrote:
> Previous dentry page uses highmem, which will cause panic in platforms
> using highmem (such as arm), since the address space of dentry pages
> from highmem directly goes into the decryption path via the function
> fscrypt_fname_disk_to_usr. But sg_init_one assumes the address is not
> from highmem, and then cause panic since it doesn't call kmap_high but
> kunmap_high is triggered at the end. To fix this problem in a simple
> way, this patch avoids to put dentry page in pagecache into highmem.
> 
> Signed-off-by: Yunlong Song <yunlong.song@huawei.com>

Reviewed-by: Chao Yu <yuchao0@huawei.com>

Thanks,