From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3187678B52; Tue, 30 Jan 2024 21:40:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706650850; cv=none; b=TJo3QyfBWGfV8E1jJGoItEA2IiyAqBgzJgqvL0Zv6E61UILTLyr0WKU/me4yK9Pt0UubbBl87N9yvpXLNJImEyWfaeYDLE2+h4wkb9vcFCW5mLNfqesF8fzjdec0LYzvBsumMw3AZdjR6KHBrk1Z/THM72TcFqpGCrY5C4B797w= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706650850; c=relaxed/simple; bh=pnAGIah8tDwiGmWDjULK1v1d3MLSt9GYUDCogaBsWHo=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version:Content-Type; b=CaDucR3yaUa70qNOj1zYTmb4/MV07Z5UEaUU9ugHf/xdoUvjr6xa8/JT1YGLgXpfpGzRpOFt3H+nBFb39l5az6/f5M7G/rPrH8/vPMnWRlFbyLY8iyjqjV2hCNo6DrFFwZstAPZPiG3wq0lmUUIUeVl66HA8hAJS6BD6W+ECbM4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=PS5LsMnj; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="PS5LsMnj" Received: by smtp.kernel.org (Postfix) with ESMTPSA id BA7A1C433C7; Tue, 30 Jan 2024 21:40:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1706650849; bh=pnAGIah8tDwiGmWDjULK1v1d3MLSt9GYUDCogaBsWHo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=PS5LsMnjn7Mbhs/Ij/7IDcnvl7UE3Kc9Cd4jIBG41zOwUg5pRGa8B/NQym6H4+J53 zzTfwxKRGuOtwlBEm8UhSzwuEr1bbZmt/S5IcXEMAafUoliin1pyE6PH0jTH/KB3Ui nO3pvM6w0m6sKxodc2DogEdVlNta7XMT+zj0V4hoY+60mItBtiX6YOrmeccXs63c3m Pk29OiSeYXfO5yQhNrign4ozByI9vlJtxiakBeyec2hJ53DULGUE/VYtKokpgysX27 djt8hj1WwehzMmQo4b2joiZ6fMajmpRNUDCHySxyaQjzQ8vYurH6iZZcU23i60PPP9 QsVqPZfGNC2Wg== Received: from sofa.misterjones.org ([185.219.108.64] helo=valley-girl.lan) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.95) (envelope-from ) id 1rUvqZ-00GOhj-Hv; Tue, 30 Jan 2024 21:40:47 +0000 From: Marc Zyngier To: Suzuki K Poulose , Oliver Upton , Sebastian Ene , Catalin Marinas , Zenghui Yu , Will Deacon , James Morse Cc: kvmarm@lists.linux.dev, kernel-team@android.com, linux-kernel@vger.kernel.org, stable@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH v2] KVM: arm64: Fix circular locking dependency Date: Tue, 30 Jan 2024 21:40:43 +0000 Message-Id: <170665083753.694736.5736115942255110234.b4-ty@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20240124091027.1477174-2-sebastianene@google.com> References: <20240124091027.1477174-2-sebastianene@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: suzuki.poulose@arm.com, oliver.upton@linux.dev, sebastianene@google.com, catalin.marinas@arm.com, yuzenghui@huawei.com, will@kernel.org, james.morse@arm.com, kvmarm@lists.linux.dev, kernel-team@android.com, linux-kernel@vger.kernel.org, stable@vger.kernel.org, linux-arm-kernel@lists.infradead.org X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false On Wed, 24 Jan 2024 09:10:28 +0000, Sebastian Ene wrote: > The rule inside kvm enforces that the vcpu->mutex is taken *inside* > kvm->lock. The rule is violated by the pkvm_create_hyp_vm() which acquires > the kvm->lock while already holding the vcpu->mutex lock from > kvm_vcpu_ioctl(). Avoid the circular locking dependency altogether by > protecting the hyp vm handle with the config_lock, much like we already > do for other forms of VM-scoped data. Applied to fixes, thanks! [1/1] KVM: arm64: Fix circular locking dependency commit: 10c02aad111df02088d1a81792a709f6a7eca6cc Cheers, M. -- Without deviation from the norm, progress is not possible.