From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 19B1BC48BD6 for ; Thu, 27 Jun 2019 00:35:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E15E521851 for ; Thu, 27 Jun 2019 00:35:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1561595729; bh=fpOF9X+K6MX51S2lgAmlVhrDgGS7QuhMNiVq3/Zuy0M=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=FRtwQFPvzR8jW8qUO7TC+lookfu7vC8U0+6/dVTFPspmnrF6UPFvjV6CsSChGfUlB 1ZYu2SzfCWMrK2mTaXB0GZ8iGyWgTSP90Bi4rwVHxvfEyuAKzW9jZwSrpGNZ5g1Xr9 8KCoYv3gtlnxm2xJoaNusHVAEYgYY/k9ClSp5UCo= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728300AbfF0Af1 (ORCPT ); Wed, 26 Jun 2019 20:35:27 -0400 Received: from mail.kernel.org ([198.145.29.99]:39880 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728257AbfF0Af0 (ORCPT ); Wed, 26 Jun 2019 20:35:26 -0400 Received: from sasha-vm.mshome.net (unknown [107.242.116.147]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 63E40217F4; Thu, 27 Jun 2019 00:35:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1561595725; bh=fpOF9X+K6MX51S2lgAmlVhrDgGS7QuhMNiVq3/Zuy0M=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=PnMtstHAOnK/+cYq3j/SygXW6dTPlCktQVE/4TRnwFzA1IQE/u00bggRs+ttYmiQ7 c55GIMHbAe+zBaJLhtkB6h2YcNOOTG19ydgWKxoiD+lHqtBJeD+GObNonx4CV5OOvY jYQp+OZu7/K65vijQtfgmCtxAPNjQypIhk5Jg1Xc= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Andrew Jones , Marc Zyngier , Sasha Levin , kvmarm@lists.cs.columbia.edu Subject: [PATCH AUTOSEL 5.1 93/95] KVM: arm/arm64: Fix emulated ptimer irq injection Date: Wed, 26 Jun 2019 20:30:18 -0400 Message-Id: <20190627003021.19867-93-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190627003021.19867-1-sashal@kernel.org> References: <20190627003021.19867-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Andrew Jones [ Upstream commit e4e5a865e9a9e8e47ac1959b629e9f3ae3b062f2 ] The emulated ptimer needs to track the level changes, otherwise the the interrupt will never get deasserted, resulting in the guest getting stuck in an interrupt storm if it enables ptimer interrupts. This was found with kvm-unit-tests; the ptimer tests hung as soon as interrupts were enabled. Typical Linux guests don't have a problem as they prefer using the virtual timer. Fixes: bee038a674875 ("KVM: arm/arm64: Rework the timer code to use a timer_map") Signed-off-by: Andrew Jones [Simplified the patch to res we only care about emulated timers here] Signed-off-by: Marc Zyngier Signed-off-by: Sasha Levin --- virt/kvm/arm/arch_timer.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/virt/kvm/arm/arch_timer.c b/virt/kvm/arm/arch_timer.c index 7fc272ecae16..1b1c449ceaf4 100644 --- a/virt/kvm/arm/arch_timer.c +++ b/virt/kvm/arm/arch_timer.c @@ -321,14 +321,15 @@ static void kvm_timer_update_irq(struct kvm_vcpu *vcpu, bool new_level, } } +/* Only called for a fully emulated timer */ static void timer_emulate(struct arch_timer_context *ctx) { bool should_fire = kvm_timer_should_fire(ctx); trace_kvm_timer_emulate(ctx, should_fire); - if (should_fire) { - kvm_timer_update_irq(ctx->vcpu, true, ctx); + if (should_fire != ctx->irq.level) { + kvm_timer_update_irq(ctx->vcpu, should_fire, ctx); return; } -- 2.20.1