From nobody Mon Mar 2 11:06:37 2026 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=pass(p=quarantine dis=none) header.from=redhat.com ARC-Seal: i=1; a=rsa-sha256; t=1772114546; cv=none; d=zohomail.com; s=zohoarc; b=Sn5SAV48reJW8aZ+BBfTrwB5fN8hz6t8wetSZMeYhxUDM4HLKwNt6X8kF4HdC5refDt9vB20NV+9cWk/OXhxc7MTp3ojRbD1JlPO1bsE64xUEsF3+poPBDs4cAXoCmH77jXTQgYPSwi3CNmHcYRvOpNkKuGL+Y8g0hMSyXM87hA= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1772114546; h=Content-Type:Content-Transfer-Encoding:Cc:Cc:Date:Date:From:From:In-Reply-To:List-Subscribe:List-Post:List-Id:List-Archive:List-Help:List-Unsubscribe:MIME-Version:Message-ID:References:Sender:Subject:Subject:To:To:Message-Id:Reply-To; bh=2WvlEsuPi6e7u3qLm/tyXMiGoFxoDbeEYBboebD1eIM=; b=m4cAmyY2bRG3Zz21U68dbQ6TNEj9lIjizJo3wuL0efXYw/Am9g6PSuZ1x8WAFUJg0mb5qHwClqb686xogtWr2NLGTP+ZBLH9Yq2V3wlgSKww4NkhDsEWvA8AyX6sBfWfQM8EJeo7hHESEd4/pjUF4ifhxM36Iuyyl7JAqNFZMR4= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=pass header.from= (p=quarantine dis=none) Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1772114546122963.6057806345084; Thu, 26 Feb 2026 06:02:26 -0800 (PST) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1vvbvL-0002uU-MF; Thu, 26 Feb 2026 09:01:03 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1vvbvF-0002lt-OM for qemu-devel@nongnu.org; Thu, 26 Feb 2026 09:01:01 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1vvbvB-0006Lu-VA for qemu-devel@nongnu.org; Thu, 26 Feb 2026 09:00:56 -0500 Received: from mx-prod-mc-03.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-83-r2k1fx2VMWKbW7KwiIZpbw-1; Thu, 26 Feb 2026 09:00:49 -0500 Received: from mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.4]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 1F5B819560B7; Thu, 26 Feb 2026 14:00:48 +0000 (UTC) Received: from localhost (unknown [10.45.242.29]) by mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id BCB5430001B9; Thu, 26 Feb 2026 14:00:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1772114452; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=2WvlEsuPi6e7u3qLm/tyXMiGoFxoDbeEYBboebD1eIM=; b=eKFd71h3rSnczP5/eZPaQbeyzDzH4woQXLaC4gCil1/G9nCSagimgcWlgsWuntyc8fXejb TM9JKbIONHnoEbp3wrb7VPKeqfoE9VGIpRqbElzTu3qUdDFEjIaQc8Jpfxxe4MO7bx+uSD yHDCroRIJ2HWzvDjPAYhc7ner98mi1I= X-MC-Unique: r2k1fx2VMWKbW7KwiIZpbw-1 X-Mimecast-MFC-AGG-ID: r2k1fx2VMWKbW7KwiIZpbw_1772114448 From: marcandre.lureau@redhat.com To: qemu-devel@nongnu.org Cc: Ben Chaney , "Michael S. Tsirkin" , =?UTF-8?q?C=C3=A9dric=20Le=20Goater?= , Paolo Bonzini , Alex Williamson , Fabiano Rosas , David Hildenbrand , =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= , Peter Xu , kvm@vger.kernel.org, Mark Kanda , =?UTF-8?q?Marc-Andr=C3=A9=20Lureau?= Subject: [PATCH v3 13/15] system/physmem: destroy ram block attributes before RCU-deferred reclaim Date: Thu, 26 Feb 2026 14:59:58 +0100 Message-ID: <20260226140001.3622334-14-marcandre.lureau@redhat.com> In-Reply-To: <20260226140001.3622334-1-marcandre.lureau@redhat.com> References: <20260226140001.3622334-1-marcandre.lureau@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.4 Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=170.10.129.124; envelope-from=marcandre.lureau@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: 22 X-Spam_score: 2.2 X-Spam_bar: ++ X-Spam_report: (2.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_SBL_CSS=3.335, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.306, RCVD_IN_VALIDITY_SAFE_BLOCKED=0.668, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=no autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: qemu development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: qemu-devel-bounces+importer=patchew.org@nongnu.org X-ZohoMail-DKIM: pass (identity @redhat.com) X-ZM-MESSAGEID: 1772114546567158500 From: Marc-Andr=C3=A9 Lureau ram_block_attributes_destroy() was called from reclaim_ramblock(), which runs as an RCU callback deferred by call_rcu(). However,when the RamDiscardManager is finalized, it will assert that its source_list is empty in the next commit. Since the RCU callback hasn't run yet, the source added by ram_block_attributes_create() is still attached. Move ram_block_attributes_destroy() into qemu_ram_free() so the source is removed synchronously. This is safe because qemu_ram_free() during shutdown runs after pause_all_vcpus(), so no vCPU thread can concurrently access the attributes via kvm_convert_memory(). Signed-off-by: Marc-Andr=C3=A9 Lureau --- system/physmem.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/system/physmem.c b/system/physmem.c index 2fb0c25c93b..cf64caf6285 100644 --- a/system/physmem.c +++ b/system/physmem.c @@ -2589,7 +2589,6 @@ static void reclaim_ramblock(RAMBlock *block) } =20 if (block->guest_memfd >=3D 0) { - ram_block_attributes_destroy(block->attributes); close(block->guest_memfd); ram_block_coordinated_discard_require(false); } @@ -2618,6 +2617,7 @@ void qemu_ram_free(RAMBlock *block) /* Write list before version */ smp_wmb(); ram_list.version++; + g_clear_pointer(&block->attributes, ram_block_attributes_destroy); call_rcu(block, reclaim_ramblock, rcu); qemu_mutex_unlock_ramlist(); } --=20 2.53.0