From patchwork Mon Dec 4 15:23:19 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?b?SsO8cmdlbiBHcm/Dnw==?= X-Patchwork-Id: 13478684 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 lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (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 44B81C4167B for ; Mon, 4 Dec 2023 15:23:44 +0000 (UTC) Received: from list by lists.xenproject.org with outflank-mailman.647119.1009852 (Exim 4.92) (envelope-from ) id 1rAAnE-0005nY-4a; Mon, 04 Dec 2023 15:23:32 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 647119.1009852; Mon, 04 Dec 2023 15:23:32 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1rAAnE-0005nP-1z; Mon, 04 Dec 2023 15:23:32 +0000 Received: by outflank-mailman (input) for mailman id 647119; Mon, 04 Dec 2023 15:23:31 +0000 Received: from se1-gles-flk1-in.inumbo.com ([94.247.172.50] helo=se1-gles-flk1.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1rAAnD-0005Xf-6L for xen-devel@lists.xenproject.org; Mon, 04 Dec 2023 15:23:31 +0000 Received: from smtp-out1.suse.de (smtp-out1.suse.de [195.135.223.130]) by se1-gles-flk1.inumbo.com (Halon) with ESMTPS id 13bc8396-92b9-11ee-9b0f-b553b5be7939; Mon, 04 Dec 2023 16:23:29 +0100 (CET) Received: from imap2.dmz-prg2.suse.org (imap2.dmz-prg2.suse.org [IPv6:2a07:de40:b281:104:10:150:64:98]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by smtp-out1.suse.de (Postfix) with ESMTPS id 2CA21220CE; Mon, 4 Dec 2023 15:23:29 +0000 (UTC) Received: from imap2.dmz-prg2.suse.org (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by imap2.dmz-prg2.suse.org (Postfix) with ESMTPS id 03EEE13588; Mon, 4 Dec 2023 15:23:28 +0000 (UTC) Received: from dovecot-director2.suse.de ([2a07:de40:b281:106:10:150:64:167]) by imap2.dmz-prg2.suse.org with ESMTPSA id 0LZJO/DubWUqJgAAn2gu4w (envelope-from ); Mon, 04 Dec 2023 15:23:28 +0000 X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: 13bc8396-92b9-11ee-9b0f-b553b5be7939 From: Juergen Gross To: xen-devel@lists.xenproject.org Cc: Juergen Gross , Dario Faggioli , George Dunlap , =?utf-8?q?Ren=C3=A9_Winther_H?= =?utf-8?q?=C3=B8jgaard?= Subject: [PATCH v2 1/3] xen/sched: fix adding offline cpu to cpupool Date: Mon, 4 Dec 2023 16:23:19 +0100 Message-Id: <20231204152321.16520-2-jgross@suse.com> X-Mailer: git-send-email 2.35.3 In-Reply-To: <20231204152321.16520-1-jgross@suse.com> References: <20231204152321.16520-1-jgross@suse.com> MIME-Version: 1.0 X-Rspamd-Server: rspamd1 Authentication-Results: smtp-out1.suse.de; none X-Rspamd-Queue-Id: 2CA21220CE X-Spamd-Result: default: False [-4.00 / 50.00]; REPLY(-4.00)[] Trying to add an offline cpu to a cpupool can crash the hypervisor, as the probably non-existing percpu area of the cpu is accessed before the availability of the cpu is being tested. This can happen in case the cpupool's granularity is "core" or "socket". Fix that by testing the cpu to be online. Fixes: cb563d7665f2 ("xen/sched: support core scheduling for moving cpus to/from cpupools") Reported-by: René Winther Højgaard Signed-off-by: Juergen Gross Reviewed-by: Jan Beulich Acked-by: George Dunlap --- V2: - enhance commit message --- xen/common/sched/cpupool.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/xen/common/sched/cpupool.c b/xen/common/sched/cpupool.c index 2e094b0cfa..ad8f608462 100644 --- a/xen/common/sched/cpupool.c +++ b/xen/common/sched/cpupool.c @@ -892,6 +892,8 @@ int cpupool_do_sysctl(struct xen_sysctl_cpupool_op *op) if ( cpu >= nr_cpu_ids ) goto addcpu_out; ret = -ENODEV; + if ( !cpu_online(cpu) ) + goto addcpu_out; cpus = sched_get_opt_cpumask(c->gran, cpu); if ( !cpumask_subset(cpus, &cpupool_free_cpus) || cpumask_intersects(cpus, &cpupool_locked_cpus) )