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 1ABC21922C4; Thu, 15 May 2025 21:36:22 +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=1747344983; cv=none; b=RnMQgi7ItnGEP24TwfeKMB3Qk+yeb5Wm7VOEz+gNb4Z52lmKVZn9bJ/XGHbfWsWBPt0GpSmpms1iGY+yMfnVSmpUf78pwl94wJ5k14BkoAeJSZGs8PEyzZJQGLZReckhkDQejby5K6AhVhTLckKw/1yVogpdU4Fjw0G2RjrAfZQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1747344983; c=relaxed/simple; bh=SeYwRuis/az6deX8AL3u4+LQM8L5xEuFWIqWaKOTXMo=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=NR3weyH+vSXjpZwb8SzZcF3wC8kZBwq6kCZHNthLUgiuZ32aesbAhKISYxBlquzv81VxSyHjXsPsriRiT/T49rY/QGTHfBGtPQ3dmSYRZZnALrfds/HDRgQ7VXhdrn0NTjxCD4/wEmg731A7cmuBSC8kuLqhp1oCZ3tmjO8S2a8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=B9y3q0MK; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="B9y3q0MK" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 60BCCC4CEE7; Thu, 15 May 2025 21:36:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1747344982; bh=SeYwRuis/az6deX8AL3u4+LQM8L5xEuFWIqWaKOTXMo=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=B9y3q0MK/zbiEU/HAxlbPGU73uzBL5vYTiUT+rCbyxgIL9AuxVykDRbstUpE6XU7x RXlB02xpxW3eJJI6gj0q9SIZYYH6RwHimPp/9mJEPL7A+co9VxQkSSBHQCNFfMrU/D shHcTlTkawpaTvtS5i6WngH3uaFb5Qz8qFAX7JAe8x+d9wlOc11hg5xeEARkIhBMM/ pF0mbwrjXD2QExW3Vq5qISkPQ/jNbE+AiaXpVR4ZJlqpT5B6sWf/6Enn7nvhF4gvQm 1IUJbVpRx6O71EaqR7GVFI6MychgN6K8wbin3rOOEV1hMFmujOdhwMj802ggKl3luU ps01aja+qBRig== Date: Thu, 15 May 2025 14:36:19 -0700 From: Kees Cook To: Eduard Zingerman Cc: Shung-Hsi Yu , bpf@vger.kernel.org, linux-mm@kvack.org, Andrii Nakryiko , Ihor Solodrai , Andrew Morton , Michal Hocko , Vlastimil Babka , Uladzislau Rezki , linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org, regressions@lists.linux.dev, Greg Kroah-Hartman , Alexei Starovoitov , Daniel Borkmann , Pawan Gupta Subject: Re: [REGRESSION] bpf verifier slowdown due to vrealloc() change since 6.15-rc6 Message-ID: <202505151435.ECC98E09@keescook> References: <20250515-bpf-verifier-slowdown-vwo2meju4cgp2su5ckj@6gi6ssxbnfqg> <202505150845.0F9E154@keescook> Precedence: bulk X-Mailing-List: linux-hardening@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, May 15, 2025 at 11:31:09AM -0700, Eduard Zingerman wrote: > On Thu, 2025-05-15 at 08:47 -0700, Kees Cook wrote: > > On Thu, May 15, 2025 at 09:12:25PM +0800, Shung-Hsi Yu wrote: > > > Bisect was done by Pawan and got to commit a0309faf1cb0 "mm: vmalloc: > > > support more granular vrealloc() sizing"[2]. To further zoom in the > > > > Can you try this patch? It's a clear bug fix, but if it doesn't improve > > things, I have another idea to rearrange the memset. > > I tried this patch on top of the commit 82f2b0b97b36 ("Linux 6.15-rc6"). > W/o the patch I observe the slowdown, test times out after 120 seconds, > with the patch test finishes in 3 seconds. Well that's pretty definitive! Thank you! I'll send out a properly formatted patch. May I add your Tested-by? -- Kees Cook