From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 0386CC7EE23 for ; Wed, 31 May 2023 12:22:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=F6Fz4Ag8HWbccx5UYlWeN2J36QO2OSbKJ+4JZzI5B9k=; b=f5EQJF/MumcTjT omEsfWTpPme+G7jDeqExJubnyVVZGvueFfUD9jlWjt2crnVw/VgPOC5otY0s/I7BlzRrG/COIQQlg +Tl+Lw9l5nzEB+4wGqDCA/11iykcyOdKjGJQZ9gr3LBnKibwPOst/IB+k/49hP3syKLxKfea6R1h8 I7IweDsdckb2gHU8FSwTt8Knl8A41NVxk+MCH03TrJ9GrZ0+0QmtYsJbkPgZTMEisCHivNsumPY7n g/U0js3wJfpbjoU3g4miyfQWuGDjFutOltQqCTm79ytpHFyl32KJIBAjS/56XIOjiR+ep0MVRUkPd MHAAn3I+aSKkVz1U/eng==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1q4KqG-00HLfv-2C; Wed, 31 May 2023 12:22:16 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1q4KqD-00HLf0-0x for linux-arm-kernel@lists.infradead.org; Wed, 31 May 2023 12:22:15 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 64FEB1042; Wed, 31 May 2023 05:22:50 -0700 (PDT) Received: from bogus (e103737-lin.cambridge.arm.com [10.1.197.49]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 2C3F63F67D; Wed, 31 May 2023 05:22:04 -0700 (PDT) Date: Wed, 31 May 2023 13:22:01 +0100 From: Sudeep Holla To: Ricardo Neri Cc: Radu Rendec , linux-kernel@vger.kernel.org, Sudeep Holla , Pierre Gondois , linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH v4 1/3] cacheinfo: Add arch specific early level initializer Message-ID: <20230531122201.3n3ak5n3cjisbmtm@bogus> References: <20230412185759.755408-1-rrendec@redhat.com> <20230412185759.755408-2-rrendec@redhat.com> <20230510191207.GA18514@ranerica-svr.sc.intel.com> <20230515093608.etfprpqn3lmgybe6@bogus> <20230518012703.GA19967@ranerica-svr.sc.intel.com> <20230518093414.qhwyogcig4wv3r5s@bogus> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20230518093414.qhwyogcig4wv3r5s@bogus> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230531_052213_402624_DF5C7633 X-CRM114-Status: GOOD ( 32.45 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Thu, May 18, 2023 at 10:34:14AM +0100, Sudeep Holla wrote: > On Wed, May 17, 2023 at 06:27:03PM -0700, Ricardo Neri wrote: > > On Mon, May 15, 2023 at 10:36:08AM +0100, Sudeep Holla wrote: > > > On Wed, May 10, 2023 at 12:12:07PM -0700, Ricardo Neri wrote: > > > > Hi, > > > > > > > > I had posted a patchset[1] for x86 that initializes > > > > ci_cacheinfo(cpu)->num_leaves during SMP boot. > > > > > > > > > > It is entirely clear to me if this is just a clean up or a fix to some > > > issue you faced ? Just wanted to let you know Prateek from AMD has couple > > > of fixes [2] > > > > My first patch is a bug fix. The second patch is clean up that results > > from fixing the bug in patch 1. > > > > > > > > > This means that early_leaves and a late cache_leaves() are equal but > > > > per_cpu_cacheinfo(cpu) is never allocated. Currently, x86 does not use > > > > fetch_cache_info(). > > > > > > > > I think that we should check here that per_cpu_cacheinfo() has been allocated to > > > > take care of the case in which early and late cache leaves remain the same: > > > > > > > > - if (cache_leaves(cpu) <= early_leaves) > > > > + if (cache_leaves(cpu) <= early_leaves && per_cpu_cacheinfo(cpu)) > > > > > > > > Otherwise, in v6.4-rc1 + [1] I observe a NULL pointer dereference from > > > > last_level_cache_is_valid(). > > > > > > > > > > I think this is different issue as Prateek was just observing wrong info > > > after cpuhotplug operations. But the patches manage the cpumap_populated > > > state better with the patches. Can you please look at that as weel ? > > > > I verified that the patches from Prateek fix a different issue. I was able > > to reproduce his issue. His patches fixes it. > > > > I still see my issue after applying Prateek's patches. > > Thanks, I thought it is different issue and good that you were able to test > them as well. Please post a proper patch for the NULL ptr dereference you > are hitting on x86. Gentle ping! Are you still observing NULL ptr dereference with v6.4-rcx ? If so, can you please post the fix as a proper patch ? Some of the patches in v6.4-rc1 are being backported, so I prefer to have all the known issues fixed before that happens. Sorry for the nag, but backport is the reason I am pushing for this. -- Regards, Sudeep _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel