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Date:   Mon, 20 Mar 2023 22:03:13 -0400
From:   "Theodore Ts'o" <tytso@mit.edu>
To:     Eric Biggers <ebiggers@kernel.org>
Cc:     Linus Torvalds <torvalds@linux-foundation.org>,
        linux-fscrypt@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        linux-security-module@vger.kernel.org,
        linux-kernel@vger.kernel.org, Jaegeuk Kim <jaegeuk@kernel.org>
Subject: Re: [GIT PULL] fscrypt fix for v6.3-rc4
Message-ID: <20230321020313.GA108653@mit.edu>
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On Mon, Mar 20, 2023 at 03:59:34PM -0700, Eric Biggers wrote:
> 
> Yes, I agree that most of the WARN_ONs should be WARN_ON_ONCEs.  I think I've
> been assuming that WARN_ON is significantly more lightweight than WARN_ON_ONCE.
> But that doesn't seem to be the case, especially since commit 19d436268dde
> ("debug: Add _ONCE() logic to report_bug()").

Another option is WARN_RATELIMITED.

As an unrelated side-note, one of the things I've been working on in
some of the ext4 code paths when I've been moving BUG_ON's to
WARN_RATELIMITED is to think about what might be needed to debug a
problem, and sometimes it can be helpful to use a printf string to
provide more context than just a WARN_ON.

Cheers,

						- Ted