From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from minute.unseen.parts (minute.unseen.parts [139.162.151.61]) (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 F1D8C7482; Thu, 30 Jan 2025 14:33:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=139.162.151.61 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738247639; cv=none; b=Lp0QdOX+HmHU8QCeRX6kLgMsRRAH5FLQzo9HUKan+trxxGlcJoDun6ER0PLmsV5CSCdZjitVodjchX+0Imb3YgaZ/O2evDHenwCnLWRO5dn8XXsGl5zw87kbf+aNgJbDVpBrDI6ZR0JTyejmSaIQHA3swPHOGXSFkg7w3/TQpJ0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738247639; c=relaxed/simple; bh=vn1F/Gd1Nh/IjOXkXXIBlxDviwARqJ5o4zcJqS23dh8=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=Pa3aPspTycL3g9N4/r6LoCRXt41D0rQ+ABBBkjr1XT10rqndvsnFOQv/9Vvmb9WC+PWfCDMXtjKRIBQ82M/3HNNUJCs3Dvi08wn5PedJuTgnIRvKymGvUoReJgCnX3dr6pwE6wwmDFw1L4/jDRhUi3WfznvalsQ8LnkahbkRT4E= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=unseen.parts; spf=pass smtp.mailfrom=unseen.parts; dkim=pass (2048-bit key) header.d=unseen.parts header.i=@unseen.parts header.b=vkwhLe27; arc=none smtp.client-ip=139.162.151.61 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=unseen.parts Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=unseen.parts Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=unseen.parts header.i=@unseen.parts header.b="vkwhLe27" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=unseen.parts; s=sig; 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:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=6I7M5sP+H1PcOzyefa9FhBz5nmy77udBHnCQGCqgbt0=; b=vkwhLe27dORNM5KaAQEOC5cKSr KotWBgeG1BoAnfEdYnjvusi9fSJceRb91ii3xRlKAwNhYHlTbvy4Al+Xwag2vDPwp62ikAVLo/KjS mWZj8EJi+YX6qukrJxqFhi23GOImhGTzgKx4LCIldUfBoqki1b8jDMOySYH+6+3Oli5OqFDAQOMOd B/7KpHtpwHMO7H5C9pZ2q9HwRw4VRqaps46Ne7q+eeHHUz0fw+h3lYVBYozxTjahvh7g+EGkyTySd LK5KbycYRdWbN/lWBm1M9pjOCbtpCTrzkUgFsI4j/c4kMV5KNXbdid8X9Cq3GHdi2Gxcy8kqap9mU A8KquPZw==; Received: from minute.unseen.parts ([139.162.151.61]:57852 helo=minute) by minute.unseen.parts with esmtpsa (TLS1.3:ECDHE_SECP256R1__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim 4.96) (envelope-from ) id 1tdVbr-0001Hj-0u; Thu, 30 Jan 2025 15:33:35 +0100 Date: Thu, 30 Jan 2025 15:33:33 +0100 From: Ivan Kokshaysky To: "Maciej W. Rozycki" Cc: Richard Henderson , Matt Turner , Oleg Nesterov , Al Viro , Arnd Bergmann , "Paul E. McKenney" , Magnus Lindholm , linux-alpha@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 0/4] alpha: stack fixes Message-ID: References: <20250129094312.27399-1-ink@unseen.parts> 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 Wed, Jan 29, 2025 at 04:02:26PM +0000, Maciej W. Rozycki wrote: > On Wed, 29 Jan 2025, Ivan Kokshaysky wrote: > > > Somehow we got away with it until recently, when we ended up with > > a stack corruption in kernel/smp.c:smp_call_function_single() due to > > its use of 32-byte aligned local data and the compiler doing clever > > things allocating it on the stack. > > Thank you for doing this work. > > I'll review/verify your changes by hand and push them through GCC and > glibc regression testing, which should hopefully pick any fallout without > having it buried among any intermittent failures, and report back. Thanks! > However, would you please cc with your submission, v2 > presumably, so as to have these changes backported? Sure. As I need to deal with bpf build failure, v2 is inevitable. > The thing is I find it quite a grave bug being fixed here, which has been > there for decades and triggering occasionally[1], and it might be the only > way for users of certain older systems to get a kernel with the fix > already applied. As you may have been aware non-BWX Alpha support has > been removed and while I'm working on bringing it back, it will likely be > missing support for specific models such as Jensen there will be no kernel > developer to look after. So getting an LTS kernel might be the only way > to get a stable system for some people. Yes, I know about your work on non-BWX Alpha and highly appreciate it. > References: > > [1] "System fails to boot when CONFIG_SMP=y", > > > Maciej Ivan.