From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A5D81606A336 for ; Mon, 2 Nov 2026 07:59:03 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=lists.infradead.org header.i=@lists.infradead.org header.a=rsa-sha256 header.s=bombadil.20210309 header.b=QMJTv7Q1; dkim=pass (1024-bit key, unprotected) header.d=linux.dev header.i=@linux.dev header.a=rsa-sha256 header.s=key1 header.b=l8fM/8oX DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:Message-ID:Date:Subject:Cc:To:From:Reply-To:Content-Type: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References: List-Unsubscribe-Post:List-Owner; bh=+JdS4G63s5YrX6ja9msk8fkBfAQWzo4U4td4gFNglHI=; b=QMJTv7Q1GEnE02U8aOSbOR3eyw FM+52UeWLTPl0hbM1sbVXL+aXvmOT+SfZCa1bFLl2wgt18/ZiRvg8Pe3fREn5eDJC9HmSCoIVJ8yv w7CC7PDjzu5RZ3apIw/lLDkdPa9COlLGeeYY8aFVf9vCpzA+Hx4xloa8k0TmkNQ9bU/Lph5f838DR fApb03Eqj4dzTluYOtTQPnjP7oetJWY+QZh4Or+pIDL2rurLdk1CWbvxzt6GPvqDWaWkY4zBfBakS ZkIN0xSPSsNCSGJya95P5TjiFlpwk/jDWDOTUoaBi8pHR7p0/FAWK5WnS73WYGFxZD5lF2MgBke4c uZ6ICAww==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.100.1 #2 (Red Hat Linux)) id 1xNmwQ-0000000FoL5-0LZi; Mon, 02 Nov 2026 07:58:54 +0000 Received: from out-222.mta1.migadu.com ([2001:41d0:203:375::de] helo=mta1.migadu.com) by bombadil.infradead.org with esmtps (Exim 4.100.1 #2 (Red Hat Linux)) id 1xNmwN-0000000FoJp-1MyY for linux-arm-kernel@lists.infradead.org; Mon, 02 Nov 2026 07:58:53 +0000 X-Envelope-To: linux-arm-kernel@lists.infradead.org DKIM-Signature: a=rsa-sha256; bh=OPCNKwKilXKP7yPXswDvwmi3hPbRw7m/9nNCGlJWJ7g=; c=simple/simple; d=linux.dev; h=from:to:subject:date:message-id:mime-version:content-type; s=key1; t=1793606328; v=1; x=1794211128; b=l8fM/8oXnEBp1ZMX+BTQ0PLIAisq+rvezWYZWxHTJ7z38YaWoyG4vstEyCCdbQnk2cdx3mHM xesZPrn2UKdNn4H+vE8A8SU+5MhBgh0VMbUh+FSpK5ANedsEX9z04YavgM1RrTci0OHv4cBtsVB qPG9BNi5kGfr3xXgquHJUwAk= X-Envelope-To: linux-arm-kernel@lists.infradead.org Received: by smtp.migadu.com with ESMTPS id 483c354dba814e72; Mon, 02 Nov 2026 07:58:47 +0000 X-Mizu-Trace-ID: 483c354dba814e72 X-Migadu-Flow: FLOW_OUT From: Fuad Tabba To: Marc Zyngier , Oliver Upton Cc: Joey Gouly , Steffen Eiden , Suzuki K Poulose , Zenghui Yu , Will Deacon , Lorenzo Stoakes , Jack Thomson , Congkai Tan , kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Fuad Tabba Subject: [PATCH v4 0/2] KVM: arm64: Clear VM-wide state when kvm_setup_vcpu() fails Date: Mon, 2 Nov 2026 07:58:41 +0000 Message-ID: <20261102075843.2556018-1-fuad.tabba@linux.dev> X-Mailer: git-send-email 2.47.3 X-Archived-By: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20261101_235851_639597_400A6D58 X-CRM114-Status: UNSURE ( 8.05 ) X-CRM114-Notice: Please train this message. X-Spam-Score: -2.1 (--) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" X-Spam-Status: No, score=-13.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=4.0.1 X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 Hi folks, Changes since v3 [1]: - New patch 2, clearing the default PMU left set by a failed INIT. - Reworded patch 1's commit message. - Rebased on 7.4-rc1. A KVM_ARM_VCPU_INIT whose kvm_setup_vcpu() fails doesn't undo its changes to VM-wide state. Patch 1 clears the feature bitmap, which the PMU attributes read before the vCPU is initialized. Patch 2 clears the default PMU, which a retry with KVM_ARM_VCPU_PMU_V3_STRICT would otherwise inherit. Tested under QEMU on a host without FEAT_NV1 (an Apple M2 MIDR, for which has_nv1() returns false), with a reproducer that fails an INIT and then initializes the PMU, directly for patch 1 and after a STRICT retry for patch 2. Based on Linux 7.4-rc1. Cheers, /fuad [1] https://lore.kernel.org/all/20260921190843.107881-1-fuad.tabba@linux.dev/ Fuad Tabba (2): KVM: arm64: Clear the VM's feature bitmap when kvm_setup_vcpu() fails KVM: arm64: Clear the default PMU when kvm_setup_vcpu() fails arch/arm64/kvm/arm.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) base-commit: 6628e7d4c6b25c8d18f1345e3a20d21829aae7e4 -- 2.47.3