Date:   Wed, 1 Dec 2021 19:26:43 -0800
From:   Andrew Morton <akpm@linux-foundation.org>
To:     Bixuan Cui <cuibixuan@linux.alibaba.com>
Cc:     linux-mm@kvack.org, linux-kernel@vger.kernel.org,
        torvalds@linux-foundation.org, leon@kernel.org, w@1wt.eu,
        keescook@chromium.org
Subject: Re: [PATCH -next] mm: delete oversized WARN_ON() in kvmalloc()
 calls
Message-Id: <20211201192643.ecb0586e0d53bf8454c93669@linux-foundation.org>
In-Reply-To: <1638410784-48646-1-git-send-email-cuibixuan@linux.alibaba.com>
References: <1638410784-48646-1-git-send-email-cuibixuan@linux.alibaba.com>
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On Thu,  2 Dec 2021 10:06:24 +0800 Bixuan Cui <cuibixuan@linux.alibaba.com> wrote:

> Delete the WARN_ON() and return NULL directly for oversized parameter
> in kvmalloc() calls.
> Also add unlikely().
> 
> Fixes: 7661809d493b ("mm: don't allow oversized kvmalloc() calls")
> Signed-off-by: Bixuan Cui <cuibixuan@linux.alibaba.com>
> ---
> There are a lot of oversize warnings and patches about kvmalloc() calls
> recently. Maybe these warnings are not very necessary.

Or maybe they are.  Please let's take a look at these warnings, one at
a time.  If a large number of them are bogus then sure, let's disable
the runtime test.  But perhaps it's the case that calling code has
genuine issues and should be repaired.