From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wm1-f73.google.com (mail-wm1-f73.google.com [209.85.128.73]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3994C85C7F for ; Tue, 23 Jan 2024 16:48:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.73 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706028520; cv=none; b=ln6hNFuccRCceavj1gimer1jEresLWikBfYpcA1a6Z8vcwGnkGP7wGR7mXZ7/FFWIzdwtgiDBLopnX/CubPnmiZ82GWREf9Rd74e5JPDi/TC5zAdIkpbwvbvLrHtE+FliYL67qf/oHF/AI9w0vsOeRBnp30RCyDQhHVTPJGxWNs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706028520; c=relaxed/simple; bh=xeMH/PTY9RvVC0crS+oE1ldLHgl6NeMg+38kZCLwc40=; h=Date:Mime-Version:Message-ID:Subject:From:To:Cc:Content-Type; b=SVUD/+kD+pCN1EFw7lFejWBl6nwz0irSDO49tAKlJG95MlqDUW7NVWk74MwwOO6ftbnKLXkg2D9vEfEZeOVZFel2FA/hDrbfshvaZK3mNx4EsYjxmH9PxwujoGU/H0oB2hCqhDo98mOOA9sBlhDfEZXqBNYDNoOn4uS5H5kwhOM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--sebastianene.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=U77jnj3i; arc=none smtp.client-ip=209.85.128.73 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--sebastianene.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="U77jnj3i" Received: by mail-wm1-f73.google.com with SMTP id 5b1f17b1804b1-40eb6ce1ddaso8550005e9.1 for ; Tue, 23 Jan 2024 08:48:36 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1706028515; x=1706633315; darn=lists.linux.dev; h=cc:to:from:subject:message-id:mime-version:date:from:to:cc:subject :date:message-id:reply-to; bh=OBfCCDyzKoRpaf1abp6hy1jxU0Vk3dNquTbtYZnKWbE=; b=U77jnj3ircuTkydM1n4NQymFCLq6QZiXAvlJNwfsXef8EMv49tXwIKn/O808lzdQ0V noCYvSUWeYjngwFil03oQpeHQ6efZiSF8ETiQgovgwiDiQIegu6YNBB5Owr+Roy4kbLR 7EJHQ4KMRWt8z6q87B4kM/AYNUfJ3sKcsl7JfJIlsf/orDrENNcdnIWS9SRyJ3J6RojW 3Ims+yA0xFmsYjgQIUJaDsDo160VGa2X/XHMAgdN6Ty5s2IMXcRPZkHvqxD/+zy8GgnH dupoRX9r8PysXBknhanNeG7OEwkWSQN4z6SjU6KU57zLEhArJg1Vnt4EiRmarUqCyqPf /j8w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1706028515; x=1706633315; h=cc:to:from:subject:message-id:mime-version:date:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=OBfCCDyzKoRpaf1abp6hy1jxU0Vk3dNquTbtYZnKWbE=; b=d61TX7WxsYcJqQrZ6cUuDJJo3CJBud6bR3fOaTDp2KEGEYHLgpvhi8Z5TQkW6PuCR/ 9uwFvCPgl/RhDyU0ovFnqKqUInXOdb9uuSVZMOXGP6bYNLt/+8vn3/OJNydL/Gn1/39w koZsvzszfhe+LEuFuEGNU5BkxLMPCtZ7axwkBnl4FprIMXm0h4Y/JCDpFOJrtkkthQuN 5mgp6CUMH5A1WJbM27VgGyoV5CM6LLnh3ctT4R3u9TOZ6qlt3whS63ydJTylyNEFcKI3 nIrZas6zD2+GCcRa0elPds48y6VaZ49m/vkNzwyHNB4A3LHJ5cNkp4EGwsbUKNUtDTM1 eWMg== X-Gm-Message-State: AOJu0YyW3XJ1IIpA2LAwFpOS/XWTsqYbEJL9xhr3w+bK+sxbagIUGDnV AKgyBQFZ93oJcnPvafXY6VT832qiKo7V6Qb4xqogIA4Z6niQ2dsGkt2eZF6SH+Ft9RRMMrVP9fQ uZACqyLjGqVmGhVlEM2JyXJPtEg== X-Google-Smtp-Source: AGHT+IH+Mlr6tHRfY6bx2hXJSMKsnWPJRGl4NYKa0sp9VUfpgnmD9gh0uN5EJJTqznNM7e5Ct5DDTXdfW1jXBoCyNNc= X-Received: from sebkvm.c.googlers.com ([fda3:e722:ac3:cc00:28:9cb1:c0a8:cd5]) (user=sebastianene job=sendgmr) by 2002:a05:600c:4e50:b0:40e:bf1e:9e84 with SMTP id e16-20020a05600c4e5000b0040ebf1e9e84mr17364wmq.5.1706028515271; Tue, 23 Jan 2024 08:48:35 -0800 (PST) Date: Tue, 23 Jan 2024 16:48:19 +0000 Precedence: bulk X-Mailing-List: kvmarm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 X-Mailer: git-send-email 2.43.0.429.g432eaa2c6b-goog Message-ID: <20240123164818.1306122-2-sebastianene@google.com> Subject: [PATCH] KVM: arm64: Fix circular locking dependency From: Sebastian Ene To: Marc Zyngier , Oliver Upton , James Morse , Suzuki K Poulose , Zenghui Yu , Catalin Marinas , Will Deacon Cc: linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, linux-kernel@vger.kernel.org, kernel-team@android.com, Sebastian Ene , stable@vger.kernel.org Content-Type: text/plain; charset="UTF-8" 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. Follow the rule by taking the config lock while getting the VM handle and make sure that this is cleaned on VM destroy under the same lock. Signed-off-by: Sebastian Ene Cc: stable@vger.kernel.org --- arch/arm64/kvm/pkvm.c | 27 +++++++++++++++++---------- 1 file changed, 17 insertions(+), 10 deletions(-) diff --git a/arch/arm64/kvm/pkvm.c b/arch/arm64/kvm/pkvm.c index 8350fb8fee0b..b7be96a53597 100644 --- a/arch/arm64/kvm/pkvm.c +++ b/arch/arm64/kvm/pkvm.c @@ -101,6 +101,17 @@ void __init kvm_hyp_reserve(void) hyp_mem_base); } +static void __pkvm_destroy_hyp_vm(struct kvm *host_kvm) +{ + if (host_kvm->arch.pkvm.handle) { + WARN_ON(kvm_call_hyp_nvhe(__pkvm_teardown_vm, + host_kvm->arch.pkvm.handle)); + } + + host_kvm->arch.pkvm.handle = 0; + free_hyp_memcache(&host_kvm->arch.pkvm.teardown_mc); +} + /* * Allocates and donates memory for hypervisor VM structs at EL2. * @@ -181,7 +192,7 @@ static int __pkvm_create_hyp_vm(struct kvm *host_kvm) return 0; destroy_vm: - pkvm_destroy_hyp_vm(host_kvm); + __pkvm_destroy_hyp_vm(host_kvm); return ret; free_vm: free_pages_exact(hyp_vm, hyp_vm_sz); @@ -194,23 +205,19 @@ int pkvm_create_hyp_vm(struct kvm *host_kvm) { int ret = 0; - mutex_lock(&host_kvm->lock); + mutex_lock(&host_kvm->arch.config_lock); if (!host_kvm->arch.pkvm.handle) ret = __pkvm_create_hyp_vm(host_kvm); - mutex_unlock(&host_kvm->lock); + mutex_unlock(&host_kvm->arch.config_lock); return ret; } void pkvm_destroy_hyp_vm(struct kvm *host_kvm) { - if (host_kvm->arch.pkvm.handle) { - WARN_ON(kvm_call_hyp_nvhe(__pkvm_teardown_vm, - host_kvm->arch.pkvm.handle)); - } - - host_kvm->arch.pkvm.handle = 0; - free_hyp_memcache(&host_kvm->arch.pkvm.teardown_mc); + mutex_lock(&host_kvm->arch.config_lock); + __pkvm_destroy_hyp_vm(host_kvm); + mutex_unlock(&host_kvm->arch.config_lock); } int pkvm_init_host_vm(struct kvm *host_kvm) -- 2.43.0.429.g432eaa2c6b-goog