From nobody Sat Jul 5 01:21:43 2025 Delivered-To: importer2@patchew.org Authentication-Results: mx.zohomail.com; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer2=patchew.org@nongnu.org Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1678295003601894.9186452328304; Wed, 8 Mar 2023 09:03:23 -0800 (PST) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1pZx84-0004Ie-K6; Wed, 08 Mar 2023 11:59:04 -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 1pZx81-0004F2-2Z; Wed, 08 Mar 2023 11:59:01 -0500 Received: from isrv.corpit.ru ([86.62.121.231]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1pZx7y-00040W-Q8; Wed, 08 Mar 2023 11:59:00 -0500 Received: from tsrv.corpit.ru (tsrv.tls.msk.ru [192.168.177.2]) by isrv.corpit.ru (Postfix) with ESMTP id 0AD06400ED; Wed, 8 Mar 2023 19:58:21 +0300 (MSK) Received: from tls.msk.ru (mjt.wg.tls.msk.ru [192.168.177.130]) by tsrv.corpit.ru (Postfix) with SMTP id B244392; Wed, 8 Mar 2023 19:58:19 +0300 (MSK) Received: (nullmailer pid 2098284 invoked by uid 1000); Wed, 08 Mar 2023 16:58:15 -0000 From: Michael Tokarev To: qemu-devel@nongnu.org Cc: qemu-stable@nongnu.org, David Hildenbrand , Peter Xu , Juan Quintela , Michael Tokarev Subject: [PATCH 16/47] migration/ram: Fix error handling in ram_write_tracking_start() Date: Wed, 8 Mar 2023 19:57:19 +0300 Message-Id: <20230308165815.2098148-16-mjt@msgid.tls.msk.ru> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20230308165035.2097594-1-mjt@msgid.tls.msk.ru> References: <20230308165035.2097594-1-mjt@msgid.tls.msk.ru> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable 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+importer2=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=86.62.121.231; envelope-from=mjt@tls.msk.ru; helo=isrv.corpit.ru X-Spam_score_int: -68 X-Spam_score: -6.9 X-Spam_bar: ------ X-Spam_report: (-6.9 / 5.0 requ) BAYES_00=-1.9, RCVD_IN_DNSWL_HI=-5, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+importer2=patchew.org@nongnu.org Sender: qemu-devel-bounces+importer2=patchew.org@nongnu.org X-ZM-MESSAGEID: 1678295004892100009 Content-Type: text/plain; charset="utf-8" From: David Hildenbrand If something goes wrong during uffd_change_protection(), we would miss to unregister uffd-wp and not release our reference. Fix it by performing the uffd_change_protection(true) last. Note that a uffd_change_protection(false) on the recovery path without a prior uffd_change_protection(false) is fine. Fixes: 278e2f551a09 ("migration: support UFFD write fault processing in ram= _save_iterate()") Cc: qemu-stable@nongnu.org Reviewed-by: Peter Xu Reviewed-by: Juan Quintela Signed-off-by: David Hildenbrand Signed-off-by: Juan Quintela (cherry picked from commit 72ef3a370836aa07261ad7aaeea27ed5cbcee342) Signed-off-by: Michael Tokarev --- migration/ram.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/migration/ram.c b/migration/ram.c index 1338e47665..8062713c75 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -1885,13 +1885,14 @@ int ram_write_tracking_start(void) block->max_length, UFFDIO_REGISTER_MODE_WP, NULL)) { goto fail; } + block->flags |=3D RAM_UF_WRITEPROTECT; + memory_region_ref(block->mr); + /* Apply UFFD write protection to the block memory range */ if (uffd_change_protection(rs->uffdio_fd, block->host, block->max_length, true, false)) { goto fail; } - block->flags |=3D RAM_UF_WRITEPROTECT; - memory_region_ref(block->mr); =20 trace_ram_write_tracking_ramblock_start(block->idstr, block->page_= size, block->host, block->max_length); --=20 2.30.2