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 lists.gnu.org (lists.gnu.org [209.51.188.17]) (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 CA3F6CAC5B0 for ; Fri, 26 Sep 2025 02:27:01 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1v1yA6-0003mz-CY; Thu, 25 Sep 2025 22:26:18 -0400 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 1v1yA5-0003l5-52 for qemu-devel@nongnu.org; Thu, 25 Sep 2025 22:26:17 -0400 Received: from mgamail.intel.com ([192.198.163.17]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1v1y9n-000615-Af for qemu-devel@nongnu.org; Thu, 25 Sep 2025 22:26:15 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1758853559; x=1790389559; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=9p5TFP5IXSL/3hMVqbtrGjD6yrnK8SNBoTLObmipajY=; b=mmS/Kp8a0VEHYDTqbkK8LIceu1yWRRZp7ChskCa2FxDCPl8cqi1uTkG/ q26s/kh4DJtU5Q3HmWcB176+12Vi15mqo5w0PZ0xx3mCaEGP3mYPCoqZ1 2tJD0iFBv1jmfDnx8dsWyjMbsMWRIVtJuhZ4cnR0PhsPiTcCnb1wOwHtN b19A8Z4h/A+6DcvHW8+oAb7DgQ6yExgB7c9fJWTRfuIfDECDTWzf0YUYS xuBaJ8lOKZjEPqrNmcPbPn8M7pO7kT10LDk6FCOoU0bRhkr7Gqom2dU1+ RddP3/84j7nA9vFl/D9nJ2LQAb/cYnE9zE4vCuiWEN7F3raxAR4BF9MpW w==; X-CSE-ConnectionGUID: OG0l3N9VS8eE5VbO+arsNA== X-CSE-MsgGUID: janTe1UZTUyfiv2adKMOKg== X-IronPort-AV: E=McAfee;i="6800,10657,11564"; a="61104656" X-IronPort-AV: E=Sophos;i="6.18,293,1751266800"; d="scan'208";a="61104656" Received: from orviesa007.jf.intel.com ([10.64.159.147]) by fmvoesa111.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 25 Sep 2025 19:25:50 -0700 X-CSE-ConnectionGUID: h+jEIRWnSsGmC1sYJ7kr4w== X-CSE-MsgGUID: 7kmMGPipThS5OCRf2YZo/Q== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.18,293,1751266800"; d="scan'208";a="177327183" Received: from unknown (HELO gnr-sp-2s-612.sh.intel.com) ([10.112.230.229]) by orviesa007-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 25 Sep 2025 19:25:49 -0700 From: Zhenzhong Duan To: qemu-devel@nongnu.org Cc: alex.williamson@redhat.com, clg@redhat.com, eric.auger@redhat.com, steven.sistare@oracle.com Subject: [PATCH 5/5] accel/kvm: Fix SIGSEGV when execute "query-balloon" after CPR transfer Date: Thu, 25 Sep 2025 22:25:40 -0400 Message-ID: <20250926022540.1884023-1-zhenzhong.duan@intel.com> X-Mailer: git-send-email 2.47.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=192.198.163.17; envelope-from=zhenzhong.duan@intel.com; helo=mgamail.intel.com X-Spam_score_int: -39 X-Spam_score: -4.0 X-Spam_bar: ---- X-Spam_report: (-4.0 / 5.0 requ) BAYES_00=-1.9, DKIM_INVALID=0.1, DKIM_SIGNED=0.1, RCVD_IN_DNSWL_MED=-2.3, RCVD_IN_VALIDITY_CERTIFIED_BLOCKED=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, SPF_PASS=-0.001, T_SPF_HELO_TEMPERROR=0.01 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+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org After CPR transfer, source QEMU close kvm fd and free kvm_state, "query-balloon" will check kvm_state->sync_mmu and trigger NULL pointer reference. Signed-off-by: Zhenzhong Duan --- accel/kvm/kvm-all.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c index 9060599cd7..a3e2d11763 100644 --- a/accel/kvm/kvm-all.c +++ b/accel/kvm/kvm-all.c @@ -3479,7 +3479,7 @@ int kvm_device_access(int fd, int group, uint64_t attr, bool kvm_has_sync_mmu(void) { - return kvm_state->sync_mmu; + return kvm_state && kvm_state->sync_mmu; } int kvm_has_vcpu_events(void) -- 2.47.1