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Date:   Wed, 14 Jun 2023 17:49:52 -0700
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Subject: Re: [PATCH v4 1/1] dax: enable dax fault handler to report
 VM_FAULT_HWPOISON
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To:     Dan Williams <dan.j.williams@intel.com>, vishal.l.verma@intel.com,
        dave.jiang@intel.com, ira.weiny@intel.com, willy@infradead.org,
        viro@zeniv.linux.org.uk, brauner@kernel.org,
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References: <20230509054714.1746956-1-jane.chu@oracle.com>
 <20230509054714.1746956-2-jane.chu@oracle.com>
 <6482999b3afd8_142af82946e@dwillia2-xfh.jf.intel.com.notmuch>
From:   Jane Chu <jane.chu@oracle.com>
In-Reply-To: <6482999b3afd8_142af82946e@dwillia2-xfh.jf.intel.com.notmuch>
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On 6/8/2023 8:16 PM, Dan Williams wrote:
[..]
>>   
>> +static inline int dax_mem2blk_err(int err)
>> +{
>> +	return (err == -EHWPOISON) ? -EIO : err;
>> +}
> 
> I think it is worth a comment on this function to indicate where this
> helper is *not* used. I.e. it's easy to grep for where the error code is
> converted for file I/O errors, but the subtlety of when the
> dax_direct_acces() return value is not translated for fault handling
> deserves a comment when we wonder why this function exists in a few
> years time.

Good point!  v5 coming up next.

thanks!
-jane