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 15DCA125C5; Thu, 7 Dec 2023 15:12:16 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="hAphyFtZ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id DB0A1C433C8; Thu, 7 Dec 2023 15:12:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1701961935; bh=bjw4PEa9SjpvxQmxru54wXvwdGXfNeLhwFsEcpsXAT8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=hAphyFtZfO1h8SVG0nkPBfxunKZZHNRrYx9jUY5GVgEZCC/PWS4frBkwVvhKTaZW6 u761SZ3lpAqh/aDUKLKe1444yi2HdqD1WgzQqBjhpPwEOOj/m87Y3061vY0cTIq+cQ IzhOr09EvZm2pGlGlg2S9q8q+KccZsOuFAx86WuRXeTCPVSWdcRrgQlLHLbXUAPGwb ZZA78tzNLtFK1v2Uz0mUds4c7EYi3Q1vdMaZF9jYvd15wz8noaM00LHxe69PcjsZST XDzVtD5K7QjJQciJ5VOiyzRFyWbeOqeZTbxpVyhGmglGvaOsJ2v2fAlsrPNkFZvEkA BVscdhDS0AFMw== 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 1rBG2v-002FcG-Ev; Thu, 07 Dec 2023 15:12:13 +0000 From: Marc Zyngier To: kvmarm@lists.linux.dev, kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org Cc: James Morse , Suzuki K Poulose , Oliver Upton , Zenghui Yu , Will Deacon , vdonnefort@google.com, stable@vger.kernel.org Subject: [PATCH 1/5] KVM: arm64: vgic: Simplify kvm_vgic_destroy() Date: Thu, 7 Dec 2023 15:11:57 +0000 Message-Id: <20231207151201.3028710-2-maz@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20231207151201.3028710-1-maz@kernel.org> References: <20231207151201.3028710-1-maz@kernel.org> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: kvmarm@lists.linux.dev, kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, james.morse@arm.com, suzuki.poulose@arm.com, oliver.upton@linux.dev, yuzenghui@huawei.com, will@kernel.org, vdonnefort@google.com, stable@vger.kernel.org X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false When destroying a vgic, we have rather cumbersome rules about when slots_lock and config_lock are held, resulting in fun buglets. The first port of call is to simplify kvm_vgic_map_resources() so that there is only one call to kvm_vgic_destroy() instead of two, with the second only holding half of the locks. For that, we kill the non-locking primitive and move the call outside of the locking altogether. This doesn't change anything (we re-acquire the locks and teardown the whole vgic), and simplifies the code significantly. Cc: stable@vger.kernel.org Signed-off-by: Marc Zyngier --- arch/arm64/kvm/vgic/vgic-init.c | 29 ++++++++++++++--------------- 1 file changed, 14 insertions(+), 15 deletions(-) diff --git a/arch/arm64/kvm/vgic/vgic-init.c b/arch/arm64/kvm/vgic/vgic-init.c index c8c3cb812783..ad7e86879eb9 100644 --- a/arch/arm64/kvm/vgic/vgic-init.c +++ b/arch/arm64/kvm/vgic/vgic-init.c @@ -382,26 +382,24 @@ void kvm_vgic_vcpu_destroy(struct kvm_vcpu *vcpu) vgic_cpu->rd_iodev.base_addr = VGIC_ADDR_UNDEF; } -static void __kvm_vgic_destroy(struct kvm *kvm) +void kvm_vgic_destroy(struct kvm *kvm) { struct kvm_vcpu *vcpu; unsigned long i; - lockdep_assert_held(&kvm->arch.config_lock); + mutex_lock(&kvm->slots_lock); vgic_debug_destroy(kvm); kvm_for_each_vcpu(i, vcpu, kvm) kvm_vgic_vcpu_destroy(vcpu); + mutex_lock(&kvm->arch.config_lock); + kvm_vgic_dist_destroy(kvm); -} -void kvm_vgic_destroy(struct kvm *kvm) -{ - mutex_lock(&kvm->arch.config_lock); - __kvm_vgic_destroy(kvm); mutex_unlock(&kvm->arch.config_lock); + mutex_unlock(&kvm->slots_lock); } /** @@ -469,25 +467,26 @@ int kvm_vgic_map_resources(struct kvm *kvm) type = VGIC_V3; } - if (ret) { - __kvm_vgic_destroy(kvm); + if (ret) goto out; - } + dist->ready = true; dist_base = dist->vgic_dist_base; mutex_unlock(&kvm->arch.config_lock); ret = vgic_register_dist_iodev(kvm, dist_base, type); - if (ret) { + if (ret) kvm_err("Unable to register VGIC dist MMIO regions\n"); - kvm_vgic_destroy(kvm); - } - mutex_unlock(&kvm->slots_lock); - return ret; + goto out_slots; out: mutex_unlock(&kvm->arch.config_lock); +out_slots: mutex_unlock(&kvm->slots_lock); + + if (ret) + kvm_vgic_destroy(kvm); + return ret; } -- 2.39.2