linux-kernel - Re: [REGRESSION] fuse: execve() fails with ETXTBSY due to async fuse

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Message-ID: <3a49282f-7d57-2756-fc20-54bc3f53a80d@fastmail.fm>
Date:   Mon, 14 Aug 2023 15:44:41 +0200
From:   Bernd Schubert <bernd.schubert@...tmail.fm>
To:     Jürg Billeter <j@...ron.ch>,
        Miklos Szeredi <miklos@...redi.hu>
Cc:     "Eric W. Biederman" <ebiederm@...ssion.com>,
        Tycho Andersen <tycho@...ho.pizza>,
        linux-fsdevel@...r.kernel.org, linux-kernel@...r.kernel.org,
        regressions@...ts.linux.dev
Subject: Re: [REGRESSION] fuse: execve() fails with ETXTBSY due to async
 fuse_flush



On 8/14/23 14:38, Jürg Billeter wrote:
> On Mon, 2023-08-14 at 14:28 +0200, Miklos Szeredi wrote:
>> On Mon, 14 Aug 2023 at 14:07, Bernd Schubert
>>> fuse: Avoid flush for O_RDONLY
>>>
>>> From: Bernd Schubert <bschubert@....com>
>>>
>>> A file opened in read-only moded does not have data to be
>>> flushed, so no need to send flush at all.
>>>
>>> This also mitigates -EBUSY for executables, which is due to
>>> async flush with commit 5a8bee63b1.
>>
>> Does it?  If I read the bug report correctly, it's the write case that
>> causes EBUSY.
> 
> Indeed, I see this when trying to execute a file after a process wrote
> to (created) that file. As far as I can tell, `ETXTBSY` can't happen on
> exec without the file being opened for writing and thus, I don't see
> this patch mitigating this bug.

Sorry, my fault, I should have read your message/report more carefully.


Bernd