From patchwork Tue Dec 17 04:42:50 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Gibson X-Patchwork-Id: 11296649 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 2C5836C1 for ; Tue, 17 Dec 2019 05:18:00 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 029662072D for ; Tue, 17 Dec 2019 05:18:00 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=gibson.dropbear.id.au header.i=@gibson.dropbear.id.au header.b="bvEC2WDA" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 029662072D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=gibson.dropbear.id.au Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Received: from localhost ([::1]:35668 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ih5F8-00061n-KA for patchwork-qemu-devel@patchwork.kernel.org; Tue, 17 Dec 2019 00:17:58 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:35075) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ih4ji-00027a-At for qemu-devel@nongnu.org; Mon, 16 Dec 2019 23:45:32 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ih4jg-0007VS-BS for qemu-devel@nongnu.org; Mon, 16 Dec 2019 23:45:30 -0500 Received: from ozlabs.org ([203.11.71.1]:37031) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1ih4jf-00071A-Dz; Mon, 16 Dec 2019 23:45:27 -0500 Received: by ozlabs.org (Postfix, from userid 1007) id 47cQWd2MzYz9sTK; Tue, 17 Dec 2019 15:43:38 +1100 (AEDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gibson.dropbear.id.au; s=201602; t=1576557821; bh=gzHHLUuZkYUSgdIhhuqRz76mOFpXx2kVpf/11Jd9AYY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=bvEC2WDACRV8Z9GYkbkys5YHwqpQRmJqXNyQKFKhnAH2Fg/gOsheHBDJMZWj6nKes MJhuOze8cQrkHcqdZTOLG+IvZhkbRYcj+a6bhXACI9RZVChHlQSEvJq3qNCiMOHjoJ u84DJ/atd0d+z4S7m42L1EZozuIic+VAjJxIcXLQ= From: David Gibson To: peter.maydell@linaro.org Subject: [PULL 56/88] ppc: Deassert the external interrupt pin in KVM on reset Date: Tue, 17 Dec 2019 15:42:50 +1100 Message-Id: <20191217044322.351838-57-david@gibson.dropbear.id.au> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20191217044322.351838-1-david@gibson.dropbear.id.au> References: <20191217044322.351838-1-david@gibson.dropbear.id.au> MIME-Version: 1.0 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 203.11.71.1 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: lvivier@redhat.com, aik@ozlabs.ru, qemu-devel@nongnu.org, groug@kaod.org, qemu-ppc@nongnu.org, clg@kaod.org, Satheesh Rajendran , David Gibson Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" From: Greg Kurz When a CPU is reset, QEMU makes sure no interrupt is pending by clearing CPUPPCstate::pending_interrupts in ppc_cpu_reset(). In the case of a complete machine emulation, eg. a sPAPR machine, an external interrupt request could still be pending in KVM though, eg. an IPI. It will be eventually presented to the guest, which is supposed to acknowledge it at the interrupt controller. If the interrupt controller is emulated in QEMU, either XICS or XIVE, ppc_set_irq() won't deassert the external interrupt pin in KVM since it isn't pending anymore for QEMU. When the vCPU re-enters the guest, the interrupt request is still pending and the vCPU will try again to acknowledge it. This causes an infinite loop and eventually hangs the guest. The code has been broken since the beginning. The issue wasn't hit before because accel=kvm,kernel-irqchip=off is an awkward setup that never got used until recently with the LC92x IBM systems (aka, Boston). Add a ppc_irq_reset() function to do the necessary cleanup, ie. deassert the IRQ pins of the CPU in QEMU and most importantly the external interrupt pin for this vCPU in KVM. Reported-by: Satheesh Rajendran Signed-off-by: Greg Kurz Message-Id: <157548861740.3650476.16879693165328764758.stgit@bahia.lan> Signed-off-by: David Gibson --- hw/ppc/ppc.c | 8 ++++++++ include/hw/ppc/ppc.h | 2 ++ target/ppc/translate_init.inc.c | 1 + 3 files changed, 11 insertions(+) diff --git a/hw/ppc/ppc.c b/hw/ppc/ppc.c index 8dd982fc1e..fab73f1b1f 100644 --- a/hw/ppc/ppc.c +++ b/hw/ppc/ppc.c @@ -1515,3 +1515,11 @@ PowerPCCPU *ppc_get_vcpu_by_pir(int pir) return NULL; } + +void ppc_irq_reset(PowerPCCPU *cpu) +{ + CPUPPCState *env = &cpu->env; + + env->irq_input_state = 0; + kvmppc_set_interrupt(cpu, PPC_INTERRUPT_EXT, 0); +} diff --git a/include/hw/ppc/ppc.h b/include/hw/ppc/ppc.h index 585be6ab98..89e1dd065a 100644 --- a/include/hw/ppc/ppc.h +++ b/include/hw/ppc/ppc.h @@ -77,6 +77,7 @@ static inline void ppc970_irq_init(PowerPCCPU *cpu) {} static inline void ppcPOWER7_irq_init(PowerPCCPU *cpu) {} static inline void ppcPOWER9_irq_init(PowerPCCPU *cpu) {} static inline void ppce500_irq_init(PowerPCCPU *cpu) {} +static inline void ppc_irq_reset(PowerPCCPU *cpu) {} #else void ppc40x_irq_init(PowerPCCPU *cpu); void ppce500_irq_init(PowerPCCPU *cpu); @@ -84,6 +85,7 @@ void ppc6xx_irq_init(PowerPCCPU *cpu); void ppc970_irq_init(PowerPCCPU *cpu); void ppcPOWER7_irq_init(PowerPCCPU *cpu); void ppcPOWER9_irq_init(PowerPCCPU *cpu); +void ppc_irq_reset(PowerPCCPU *cpu); #endif /* PPC machines for OpenBIOS */ diff --git a/target/ppc/translate_init.inc.c b/target/ppc/translate_init.inc.c index ba726dec4d..64a838095c 100644 --- a/target/ppc/translate_init.inc.c +++ b/target/ppc/translate_init.inc.c @@ -10461,6 +10461,7 @@ static void ppc_cpu_reset(CPUState *s) env->pending_interrupts = 0; s->exception_index = POWERPC_EXCP_NONE; env->error_code = 0; + ppc_irq_reset(cpu); /* tininess for underflow is detected before rounding */ set_float_detect_tininess(float_tininess_before_rounding,