From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 1971C346E4E for ; Fri, 16 Jan 2026 12:06:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768565197; cv=none; b=Ie4Ti/taKroNW9IfBAeUcCFrQpfr032L+3eUAASYnVl+JLJE1MIbaqMG2TwPZklYvga193s/1j50sImZJFDd5BY7yoslFkEOivB0cjljIpUl/JFFpMZ/FPDQfupKXI0OQFxK5l6vHz2zdgbvLpsaOWzn7tQpLXQ/eDXpga0Mso8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768565197; c=relaxed/simple; bh=mPHV+hdOqxsshztbjv0x8mFcOauVR5FvveAehgYRJyk=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=BShm79dKzYHJMyvQ79RlQgUIgQsAa1d38J5lY6gapLio15GpuHRLThOwn5u3PbgseKxefs0oXHCWtrSeSVh4X7KrK36B1ufUHK23stbJODyqJTvzJZ1oA3tX+bcxhpUQbKVFOvUsbEesWMWk7Ft02ejji70bvDJMx02vHgMV4ro= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id B86B81515; Fri, 16 Jan 2026 04:06:28 -0800 (PST) Received: from arm.com (usa-sjc-mx-foss1.foss.arm.com [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 6A2033F694; Fri, 16 Jan 2026 04:06:34 -0800 (PST) Date: Fri, 16 Jan 2026 12:06:31 +0000 From: Catalin Marinas To: Breno Leitao Cc: Will Deacon , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, kernel-team@meta.com, clm@fb.com Subject: Re: [PATCH] arm64: mm: warn once for ioremap attempts on RAM mappings Message-ID: References: <20251222-arm64_ioremap-v1-1-30ff5f718b61@debian.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20251222-arm64_ioremap-v1-1-30ff5f718b61@debian.org> On Mon, Dec 22, 2025 at 07:28:55AM -0800, Breno Leitao wrote: > Replace WARN_ON with WARN_ONCE when detecting attempts to ioremap > RAM. This prevents log spam when a misbehaving driver repeatedly tries > to map RAM via ioremap. > > A single warning is more than enough to show the broken code path, and > extra reports don't add extra information. > > Warning floods have been seen in production environments where broken > external drivers hit this code path thousand of times, causing > unnecessary messages to be printed and pressure on the serial console. > > Signed-off-by: Breno Leitao It looks fine to me but it's not urgent for 6.19, so I'll leave it to Will. Acked-by: Catalin Marinas