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Subject: Re: [f2fs-dev] [PATCH v3] f2fs: compress: support chksum
To:     Eric Biggers <ebiggers@kernel.org>
CC:     <jaegeuk@kernel.org>, <linux-kernel@vger.kernel.org>,
        <linux-f2fs-devel@lists.sourceforge.net>
References: <20201126103209.67985-1-yuchao0@huawei.com>
 <X86Sb2pvD53MzO5+@gmail.com>
From:   Chao Yu <yuchao0@huawei.com>
Message-ID: <e6bc842d-90a2-d4ce-56be-594bcebaea37@huawei.com>
Date:   Tue, 8 Dec 2020 09:18:37 +0800
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On 2020/12/8 4:37, Eric Biggers wrote:
> On Thu, Nov 26, 2020 at 06:32:09PM +0800, Chao Yu wrote:
>> +	if (!ret && fi->i_compress_flag & 1 << COMPRESS_CHKSUM) {
> 
> This really could use some parentheses.  People shouldn't have to look up a
> C operator precedence table to understand the code.

Will add parentheses to avoid misread.

> 
>> +		u32 provided = le32_to_cpu(dic->cbuf->chksum);
>> +		u32 calculated = f2fs_crc32(sbi, dic->cbuf->cdata, dic->clen);
>> +
>> +		if (provided != calculated) {
>> +			if (!is_inode_flag_set(dic->inode, FI_COMPRESS_CORRUPT)) {
>> +				set_inode_flag(dic->inode, FI_COMPRESS_CORRUPT);
>> +				printk_ratelimited(
>> +					"%sF2FS-fs (%s): checksum invalid, nid = %lu, %x vs %x",
>> +					KERN_INFO, sbi->sb->s_id, dic->inode->i_ino,
>> +					provided, calculated);
>> +			}
>> +			set_sbi_flag(sbi, SBI_NEED_FSCK);
>> +			WARN_ON_ONCE(1);
> 
> WARN, WARN_ON_ONCE, BUG, BUG_ON, etc. are only for kernel bugs, not for invalid
> inputs from disk or userspace.
> 
> There is already a log message printed just above, so it seems this WARN_ON_ONCE
> should just be removed.

Jaegeuk wants to give WARN_ON and marking a FSCK flag without returning EFSCORRUPTED,

Jaegeuk, thoughts?

Thanks,

> 
> - Eric
> .
>