From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1DA7F433D4; Thu, 14 Mar 2024 08:39:52 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1710405593; cv=none; b=TX2A8ajYxbyf4oXP4RuL4BR0g4oFXSwQRpeDGy8CbJG293S9H92Pmmt88AncSe1WXKRyiut+77r9mYosNFdUG2gDe43J4VdvAO8q8t+fBA9L6hF29cbasb17vTEl45rx3xeI1o8G7DqUL3/PO6GOlXOYlCz4WjGKcZWqE7/wVV8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1710405593; c=relaxed/simple; bh=Pxk9h0+NJJSQGNZfBddW8VXxiAc/KVW3MLayKN9JI9A=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=uF4nqXJWX4BMXOlFTDmj3YBMBNmqPuVeD5bxLMEmsU6GlgfrjEyUTJ1uxQ/tHvc/hQUHJrecvI86SMy/14DCwhYGniiOS0EuYtjqo1yWNKPYtIQSqcya1gVB4HbuUoGjGPomzJte+9cAuZbIfXVJ/iWgMaqBC6ATUlCm3tUhq60= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7F403C433F1; Thu, 14 Mar 2024 08:39:48 +0000 (UTC) Date: Thu, 14 Mar 2024 08:39:46 +0000 From: Catalin Marinas To: "Russell King (Oracle)" Cc: Marek Szyprowski , Sudeep Holla , "Christoph Lameter (Ampere)" , Mark Rutland , "linux-pm@vger.kernel.org" , "Rafael J. Wysocki" , Viresh Kumar , Will Deacon , Jonathan.Cameron@huawei.com, Matteo.Carlini@arm.com, Valentin.Schneider@arm.com, akpm@linux-foundation.org, anshuman.khandual@arm.com, Eric Mackay , dave.kleikamp@oracle.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, robin.murphy@arm.com, vanshikonda@os.amperecomputing.com, yang@os.amperecomputing.com, Nishanth Menon , Stephen Boyd Subject: Re: [PATCH v3] ARM64: Dynamically allocate cpumasks and increase supported CPUs to 512 Message-ID: References: <37099a57-b655-3b3a-56d0-5f7fbd49d7db@gentwo.org> <9352f410-9dad-ac89-181a-b3cfc86176b8@linux.com> <432c1980-b00f-4b07-9e24-0bec52ccb5d6@samsung.com> Precedence: bulk X-Mailing-List: linux-pm@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: On Wed, Mar 13, 2024 at 05:13:33PM +0000, Russell King wrote: > So, I wonder whether what you're seeing is a latent bug which is > being tickled by the presence of the CPU masks being off-stack > changing the kernel timing. > > I would suggest the printk debug approach may help here to see when > the OPPs are begun to be parsed, when they're created etc and their > timing relationship to being used. Given the suspicion, it's possible > that the mere addition of printk() may "fix" the problem, which again > would be another semi-useful data point. It might be an init order problem. Passing "initcall_debug" on the cmdline might help a bit. It would also be useful in dev_pm_opp_set_config(), in the WARN_ON block, to print opp_table->opp_list.next to get an idea whether it looks like a valid pointer or memory corruption. -- Catalin