From patchwork Mon Jan 24 18:29:51 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 535670 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A259BC35273 for ; Mon, 24 Jan 2022 20:57:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1443582AbiAXU52 (ORCPT ); Mon, 24 Jan 2022 15:57:28 -0500 Received: from dfw.source.kernel.org ([139.178.84.217]:42638 "EHLO dfw.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1358864AbiAXUw7 (ORCPT ); Mon, 24 Jan 2022 15:52:59 -0500 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id ABB7060B0B; Mon, 24 Jan 2022 20:52:58 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7EB09C340E7; Mon, 24 Jan 2022 20:52:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1643057578; bh=6fZMCQloQ2t3ladZ5ITB1GxhYi5y6jBkCeqwFsjnSLI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=1T2Daog9HuvSn5QL731fQreO1aZXcyOPsw3J5JUFlUo9ZKURE9sygQT+3qgnEec/i O/lpjNPGciomdHInM3EUHuQfJ5N6xJNbl5gtJqAXmRkCydsV04Yq6x9Zzl4sShtnDd uJWF3kHcAUJMgDGv5EQb+W4iN9XbYueaWnrjUSEU= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Marcelo Tosatti , Paolo Bonzini Subject: [PATCH 5.16 0002/1039] KVM: VMX: switch blocked_vcpu_on_cpu_lock to raw spinlock Date: Mon, 24 Jan 2022 19:29:51 +0100 Message-Id: <20220124184125.216249731@linuxfoundation.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220124184125.121143506@linuxfoundation.org> References: <20220124184125.121143506@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Marcelo Tosatti commit 5f02ef741a785678930f3ff0a8b6b2b0ef1bb402 upstream. blocked_vcpu_on_cpu_lock is taken from hard interrupt context (pi_wakeup_handler), therefore it cannot sleep. Switch it to a raw spinlock. Fixes: [41297.066254] BUG: scheduling while atomic: CPU 0/KVM/635218/0x00010001 [41297.066323] Preemption disabled at: [41297.066324] [] irq_enter_rcu+0xf/0x60 [41297.066339] Call Trace: [41297.066342] [41297.066346] dump_stack_lvl+0x34/0x44 [41297.066353] ? irq_enter_rcu+0xf/0x60 [41297.066356] __schedule_bug.cold+0x7d/0x8b [41297.066361] __schedule+0x439/0x5b0 [41297.066365] ? task_blocks_on_rt_mutex.constprop.0.isra.0+0x1b0/0x440 [41297.066369] schedule_rtlock+0x1e/0x40 [41297.066371] rtlock_slowlock_locked+0xf1/0x260 [41297.066374] rt_spin_lock+0x3b/0x60 [41297.066378] pi_wakeup_handler+0x31/0x90 [kvm_intel] [41297.066388] sysvec_kvm_posted_intr_wakeup_ipi+0x9d/0xd0 [41297.066392] [41297.066392] asm_sysvec_kvm_posted_intr_wakeup_ipi+0x12/0x20 ... Signed-off-by: Marcelo Tosatti Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini Signed-off-by: Greg Kroah-Hartman --- arch/x86/kvm/vmx/posted_intr.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) --- a/arch/x86/kvm/vmx/posted_intr.c +++ b/arch/x86/kvm/vmx/posted_intr.c @@ -15,7 +15,7 @@ * can find which vCPU should be waken up. */ static DEFINE_PER_CPU(struct list_head, blocked_vcpu_on_cpu); -static DEFINE_PER_CPU(spinlock_t, blocked_vcpu_on_cpu_lock); +static DEFINE_PER_CPU(raw_spinlock_t, blocked_vcpu_on_cpu_lock); static inline struct pi_desc *vcpu_to_pi_desc(struct kvm_vcpu *vcpu) { @@ -121,9 +121,9 @@ static void __pi_post_block(struct kvm_v new.control) != old.control); if (!WARN_ON_ONCE(vcpu->pre_pcpu == -1)) { - spin_lock(&per_cpu(blocked_vcpu_on_cpu_lock, vcpu->pre_pcpu)); + raw_spin_lock(&per_cpu(blocked_vcpu_on_cpu_lock, vcpu->pre_pcpu)); list_del(&vcpu->blocked_vcpu_list); - spin_unlock(&per_cpu(blocked_vcpu_on_cpu_lock, vcpu->pre_pcpu)); + raw_spin_unlock(&per_cpu(blocked_vcpu_on_cpu_lock, vcpu->pre_pcpu)); vcpu->pre_pcpu = -1; } } @@ -154,11 +154,11 @@ int pi_pre_block(struct kvm_vcpu *vcpu) local_irq_disable(); if (!WARN_ON_ONCE(vcpu->pre_pcpu != -1)) { vcpu->pre_pcpu = vcpu->cpu; - spin_lock(&per_cpu(blocked_vcpu_on_cpu_lock, vcpu->pre_pcpu)); + raw_spin_lock(&per_cpu(blocked_vcpu_on_cpu_lock, vcpu->pre_pcpu)); list_add_tail(&vcpu->blocked_vcpu_list, &per_cpu(blocked_vcpu_on_cpu, vcpu->pre_pcpu)); - spin_unlock(&per_cpu(blocked_vcpu_on_cpu_lock, vcpu->pre_pcpu)); + raw_spin_unlock(&per_cpu(blocked_vcpu_on_cpu_lock, vcpu->pre_pcpu)); } do { @@ -215,7 +215,7 @@ void pi_wakeup_handler(void) struct kvm_vcpu *vcpu; int cpu = smp_processor_id(); - spin_lock(&per_cpu(blocked_vcpu_on_cpu_lock, cpu)); + raw_spin_lock(&per_cpu(blocked_vcpu_on_cpu_lock, cpu)); list_for_each_entry(vcpu, &per_cpu(blocked_vcpu_on_cpu, cpu), blocked_vcpu_list) { struct pi_desc *pi_desc = vcpu_to_pi_desc(vcpu); @@ -223,13 +223,13 @@ void pi_wakeup_handler(void) if (pi_test_on(pi_desc) == 1) kvm_vcpu_kick(vcpu); } - spin_unlock(&per_cpu(blocked_vcpu_on_cpu_lock, cpu)); + raw_spin_unlock(&per_cpu(blocked_vcpu_on_cpu_lock, cpu)); } void __init pi_init_cpu(int cpu) { INIT_LIST_HEAD(&per_cpu(blocked_vcpu_on_cpu, cpu)); - spin_lock_init(&per_cpu(blocked_vcpu_on_cpu_lock, cpu)); + raw_spin_lock_init(&per_cpu(blocked_vcpu_on_cpu_lock, cpu)); } bool pi_has_pending_interrupt(struct kvm_vcpu *vcpu)