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Wed, 29 Apr 2026 01:08:26 +0000 Message-ID: <0dacbe06-5b97-4dee-b8f2-a235b70448e2@intel.com> Date: Wed, 29 Apr 2026 09:08:18 +0800 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] KVM: VMX: Fall back to IRR scan when PIR is empty despite PID.ON being set To: Sean Christopherson CC: Paolo Bonzini , , Jim Mattson , Gao Chao , Farrah Chen References: <20260428070349.1633238-1-chenyi.qiang@intel.com> <3235eb76-9b28-4000-920a-491659927e67@redhat.com> <04c954e6-a23a-4cc8-8bd3-5882a951a8cc@intel.com> Content-Language: en-US From: Chenyi Qiang In-Reply-To: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-ClientProxiedBy: SG2P153CA0003.APCP153.PROD.OUTLOOK.COM (2603:1096::13) To DM3PR11MB8735.namprd11.prod.outlook.com (2603:10b6:0:4b::20) Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: DM3PR11MB8735:EE_|SN7PR11MB8264:EE_ X-MS-Office365-Filtering-Correlation-Id: 85c809f5-0d33-4cc0-17bf-08dea58bd133 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|376014|366016|1800799024|18002099003|22082099003|56012099003; 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I've seen this WARN > 2-3 times over the last year, but it was never reproducible, and so intermittent > that I couldn't even correlate what I was doing at the time with the WARN. It's not something special. The stress test is only to create and tear down 20 nested VM instance in a cycle. It often takes more than 20 cycles to reproduce this issue.