From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp-1.orcon.net.nz (smtp-1.orcon.net.nz [60.234.4.34]) (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 D79BB225760; Tue, 20 Jan 2026 08:26:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=60.234.4.34 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768897617; cv=none; b=hOtOWOer8IGc7wOwZXKFyPNn4Vf4HRIvrYLqsJ+DnZE61Z0kFkyDYmKIeB3s6nrs6J6F5QpiZJQ+gObnPvz8x81dCD1nzp0pyYqcErixfAvZkoi/ow67ZXUjJ3a8eJMOcUq3woDxeYZ3aSCVHDePIJ37mA/diuzUX51JLQzMN70= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768897617; c=relaxed/simple; bh=yQHkV2QVx6UKOIXkpiHTYa9Np87EJzgjALhFPd1miL0=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=p4P8X580VS20lBz56KSVpXKGGqilGvIspRR/7cQpf27V2Ab8tRq3fNEA2Pe5ej5E/2oY8XcUWBkqYsxT71rIwcHbuihg8qEswf/pzTdn80F/6elWhnRa00ncIcJouv2205goKvi1iTellW834R04rV7r5xUwK+m4qKZj+fZGgTE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=orcon.net.nz; spf=pass smtp.mailfrom=orcon.net.nz; arc=none smtp.client-ip=60.234.4.34 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=orcon.net.nz Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=orcon.net.nz Received: from [121.99.247.178] (port=65143 helo=creeky) by smtp-1.orcon.net.nz with esmtpa (Exim 4.90_1) (envelope-from ) id 1vi6PF-00086n-Sm; Tue, 20 Jan 2026 20:44:06 +1300 Date: Tue, 20 Jan 2026 20:44:00 +1300 From: Michael Cree To: John Paul Adrian Glaubitz Cc: Magnus Lindholm , linux-kernel@vger.kernel.org, linux-alpha@vger.kernel.org, hch@infradead.org, macro@orcam.me.uk, mattst88@gmail.com, richard.henderson@linaro.org, ink@unseen.parts Subject: Re: [PATCH 0/1] alpha: fix user-space corruption during memory compaction Message-ID: Mail-Followup-To: Michael Cree , John Paul Adrian Glaubitz , Magnus Lindholm , linux-kernel@vger.kernel.org, linux-alpha@vger.kernel.org, hch@infradead.org, macro@orcam.me.uk, mattst88@gmail.com, richard.henderson@linaro.org, ink@unseen.parts References: <20260102173603.18247-1-linmag7@gmail.com> <63b2087350d6990f0e348a8028f006924363c5d0.camel@physik.fu-berlin.de> Precedence: bulk X-Mailing-List: linux-alpha@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: <63b2087350d6990f0e348a8028f006924363c5d0.camel@physik.fu-berlin.de> X-GeoIP: NZ X-Spam_score: -2.9 X-Spam_score_int: -28 X-Spam_bar: -- On Fri, Jan 02, 2026 at 06:57:28PM +0100, John Paul Adrian Glaubitz wrote: > Hi Magnus, > > On Fri, 2026-01-02 at 18:30 +0100, Magnus Lindholm wrote: > > This patch fixes long-standing user-space crashes on Alpha systems > > when memory compaction is enabled. > > > > Observed symptoms include: > > - sporadic SIGSEGV in unrelated user programs > > - glibc allocator failures (e.g. "unaligned tcache chunk detected") > > - gcc "internal compiler error" > > - heap corruption detected by malloc consistency checks > > > > The failures occur only when page migration / compaction is active > > and disappear when compaction is disabled. They affect both UP and > > SMP kernels and are not specific to a particular Alpha CPU model. > > Wow, thanks for fixing this! This has been indeed a longstanding issue and > seeing it fixed would be great. > > I'm CC'ing Michael Cree who has been observing the issue as well and could > help testing your series. I've successfully run a 6.18.3 kernel with this patch and CONFIG_COMPACTION on for almost four days on an XP1000 without any problem. I would normally see one of the observed problems described above within a day, and certainly within two days, when running with a bad kernel, so this is looking good. Feel free to add: Tested-by: Michael Cree Cheers, Michael.