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Date: Wed, 30 Oct 2024 00:11:55 +0000
From: Al Viro <viro@zeniv.linux.org.uk>
To: Song Liu <song@kernel.org>
Cc: bpf@vger.kernel.org, linux-fsdevel@vger.kernel.org,
	linux-kernel@vger.kernel.org, kernel-team@meta.com,
	andrii@kernel.org, eddyz87@gmail.com, ast@kernel.org,
	daniel@iogearbox.net, martin.lau@linux.dev, brauner@kernel.org,
	jack@suse.cz, kpsingh@kernel.org, mattbobrowski@google.com,
	amir73il@gmail.com, repnop@google.com, jlayton@kernel.org,
	josef@toxicpanda.com
Subject: Re: [RFC bpf-next fanotify 2/5] samples/fanotify: Add a sample
 fanotify fastpath handler
Message-ID: <20241030001155.GF1350452@ZenIV>
References: <20241029231244.2834368-1-song@kernel.org>
 <20241029231244.2834368-3-song@kernel.org>
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Sender: Al Viro <viro@ftp.linux.org.uk>

On Tue, Oct 29, 2024 at 04:12:41PM -0700, Song Liu wrote:
> +		if (strstr(file_name->name, item->prefix) == (char *)file_name->name)

	Huh?  "Find the first substring (if any) equal to item->prefix and
then check if that happens to be in the very beginning"???

	And you are placing that into the place where it's most likely to cause
the maximal braindamage and spread all over the tree.  Wonderful ;-/

	Where does that "idiom" come from, anyway?  Java?  Not the first time
I see that kind of garbage; typecast is an unusual twist, though...