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Date: Thu, 31 May 2018 11:28:08 +0300
From: Alexey Dobriyan <adobriyan@gmail.com>
To: Al Viro <viro@ZenIV.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH 1/5] procfs: get rid of ancient BS in pid_revalidate()
 uses
Message-ID: <20180531082808.GA5113@avx2>
References: <20180526000302.GK30522@ZenIV.linux.org.uk>
 <20180526000410.10804-1-viro@ZenIV.linux.org.uk>
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On Sat, May 26, 2018 at 01:04:06AM +0100, Al Viro wrote:
> +	pid_update_inode(task, inode);
>  	d_set_d_op(dentry, &pid_dentry_operations);
>  	d_add(dentry, inode);
> -	/* Close the race of the process dying before we return the dentry */
> -	if (pid_revalidate(dentry, 0))
> -		return 0;
> -out:
> -	return -ENOENT;
> +	return 0;
>  }

ACK this. I never understood what race is prevented if process can
exit after pid_revalidate().