From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) (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 F397C1B5EDB; Thu, 29 Aug 2024 22:29:09 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=90.155.50.34 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724970552; cv=none; b=AwRmxhtDLCy4DuZZVqpx5HkqQZwxCaYOs41INhUeoyW/6MD5laBwBTqozYcsttmyw0sfCJwmEugDafMUaQXKurQ7T9D6qInasPSjLOnV7bxw98raWv+7BqwknqvZ8WREsasmowTluzzOGKbng4PbAbzPWedo+sBKKtWxLoJ7FDo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724970552; c=relaxed/simple; bh=Tw5rg3SsYeGdNH8H/SojvzU2mY4Enp6rJZHNecxbN/w=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=oQBcTe6NQRCqPo9GHxL1b0cbop44YKZnz5SrSD+1fk7Zrg2OEtA4VUEL1CANpG297e1bTa8H/wBRRVB3rzM9Ji9L2GxwJsCNzY1ZvjgshLlJdRQ3QoD62NEKTTefAKNSV6FqvDG14DEI3VIh97jvX/WkhTQi96V2Q+JF0fTeG9o= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=iRnLKAC4; arc=none smtp.client-ip=90.155.50.34 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="iRnLKAC4" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=lb1pyj5zxbGFHDqjyX82l5HJgvNKijLaWdmPvU8hETY=; b=iRnLKAC4B8wm5XBnfdv0OVgM/d cEEof1zWyfZzKsn0z3w44QW/32Zhgbp812aBTx+jhTo+SftWEQApD0+ZV+zNUGEWAShj/Vw2N8APd BiwXdVrkHv1Qp8VeZ0AkV+9CB6Q2ARQARu80xwEvI6Bc+QqUo9kej01g5gZEcEdB6OlMafb9uy2r9 m+bB++s/vJjuRvxLRhC/NhftzSfzj4lu6tJfEQRVAZhpHm85EhddPn4mJAk4s9E8IpqkpiyL6lEkj /qzv/vZTrSa37pIunplwVC0J1ymXvsPyufqiCrCu0UZGrHONGNZBBtOBhmLEZYRKL2tlsihuSU3TR c+J0Mcbg==; Received: from willy by casper.infradead.org with local (Exim 4.98 #2 (Red Hat Linux)) id 1sjndZ-00000002aLf-1Xma; Thu, 29 Aug 2024 22:29:05 +0000 Date: Thu, 29 Aug 2024 23:29:05 +0100 From: Matthew Wilcox To: Yosry Ahmed Cc: Piotr Oniszczuk , Pedro Falcato , Nhat Pham , Linux regressions mailing list , LKML , Johannes Weiner , Linux-MM Subject: Re: [regression] oops on heavy compilations ("kernel BUG at mm/zswap.c:1005!" and "Oops: invalid opcode: 0000") Message-ID: References: <6f65e3a6-5f1a-4fda-b406-17598f4a72d5@leemhuis.info> <02D2DA66-4A91-4033-8B98-ED25FC2E0CD6@gmail.com> <3D1B8F1F-2C41-4CCD-A5D7-41CF412F99DE@gmail.com> 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: On Thu, Aug 29, 2024 at 02:54:25PM -0700, Yosry Ahmed wrote: > Looking at the zswap commits between 6.8 and 6.9, ignoring cleanups > and seemingly irrelevant patches (e.g. swapoff fixups), I think the > some likely candidates could be the following, but this is not really > based on any scientific methodology: > > 44c7c734a5132 mm/zswap: split zswap rb-tree > c2e2ba770200b mm/zswap: only support zswap_exclusive_loads_enabled > a230c20e63efe mm/zswap: zswap entry doesn't need refcount anymore > 8409a385a6b41 mm/zswap: improve with alloc_workqueue() call > 0827a1fb143fa mm/zswap: invalidate zswap entry when swap entry free > > I also noticed that you are using z3fold as the zpool. Is the problem > reproducible with zsmalloc? I wouldn't be surprised if there's a > z3fold bug somewhere. You're assuming that it's a zswap/zsmalloc/... bug. If it's a random scribble, as suggested by Takero Funaki: https://lore.kernel.org/linux-mm/CAPpoddere2g=kkMzrxuJ1KCG=0Hg1-1v=ppg4dON9wK=pKq2uQ@mail.gmail.com/ then focusing on zswap will not be fruitful.