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Date:   Wed, 20 Apr 2022 16:50:33 +0800
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From:   "chenxiaosong (A)" <chenxiaosong2@huawei.com>
Subject: Re: [PATCH -next 1/2] nfs: nfs{,4}_file_flush should consume
 writeback error
To:     Trond Myklebust <trondmy@hammerspace.com>,
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在 2022/4/12 22:27, Trond Myklebust 写道:

>
> It will clear ENOSPC, EDQUOT and EFBIG. It should not clear other
> errors that are not supposed to be reported by write().
> 
> As I keep repeating, that is _documented behaviour_!
> 

Hi Trond:

You may mean that write(2) manpage described:

> Since Linux 4.13, errors from write-back come with a promise that
> they may be reported by subsequent.  write(2) requests, and will be
> reported by a subsequent fsync(2) (whether or not they were also
> reported by write(2)).

The manpage mentioned that "reported by a subsequent fsync(2)", your 
patch[1] clear the wb err on _async_ write(), and wb err will _not_ be 
reported by subsequent fsync(2), is it documented behaviour?

All other filesystems will _not_ clear any wb err on _async_ write().

[1] 
https://patchwork.kernel.org/project/linux-nfs/patch/20220411213346.762302-4-trondmy@kernel.org/