From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758336AbcIMN6l (ORCPT ); Tue, 13 Sep 2016 09:58:41 -0400 Received: from down.free-electrons.com ([37.187.137.238]:37933 "EHLO mail.free-electrons.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1756766AbcIMN6d (ORCPT ); Tue, 13 Sep 2016 09:58:33 -0400 From: Boris Brezillon To: Thomas Gleixner , Jason Cooper , Marc Zyngier Cc: Nicolas Ferre , Alexandre Belloni , linux-kernel@vger.kernel.org, Boris Brezillon , stable@vger.kernel.org Subject: [PATCH v3 2/2] irqchip/atmel-aic: Fix potential deadlock in ->xlate() Date: Tue, 13 Sep 2016 15:58:29 +0200 Message-Id: <1473775109-4192-2-git-send-email-boris.brezillon@free-electrons.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1473775109-4192-1-git-send-email-boris.brezillon@free-electrons.com> References: <1473775109-4192-1-git-send-email-boris.brezillon@free-electrons.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org aic5_irq_domain_xlate() and aic_irq_domain_xlate() take the generic chip lock without disabling interrupts, which can lead to a deadlock if an interrupt occurs while the lock is held in one of these functions. Replace irq_gc_{lock,unlock}() calls by raw_spin_{lock_irqsave,unlock_irqrestore}() ones to prevent this bug from happening. Signed-off-by: Boris Brezillon Fixes: b1479ebb7720 ("irqchip: atmel-aic: Add atmel AIC/AIC5 drivers") Cc: Acked-by: Marc Zyngier --- Changes in v3: - introduce and use the irq_gc_{lock_irqsave,unlock_irqrestore}() helpers Changes in v2: - add Marc's ack - fix stable ML address fixup! irqchip/atmel-aic: Fix potential deadlock in ->xlate() --- drivers/irqchip/irq-atmel-aic.c | 5 +++-- drivers/irqchip/irq-atmel-aic5.c | 5 +++-- 2 files changed, 6 insertions(+), 4 deletions(-) diff --git a/drivers/irqchip/irq-atmel-aic.c b/drivers/irqchip/irq-atmel-aic.c index 112e17c2768b..37f952dd9fc9 100644 --- a/drivers/irqchip/irq-atmel-aic.c +++ b/drivers/irqchip/irq-atmel-aic.c @@ -176,6 +176,7 @@ static int aic_irq_domain_xlate(struct irq_domain *d, { struct irq_domain_chip_generic *dgc = d->gc; struct irq_chip_generic *gc; + unsigned long flags; unsigned smr; int idx; int ret; @@ -194,11 +195,11 @@ static int aic_irq_domain_xlate(struct irq_domain *d, gc = dgc->gc[idx]; - irq_gc_lock(gc); + irq_gc_lock_irqsave(gc, flags); smr = irq_reg_readl(gc, AT91_AIC_SMR(*out_hwirq)); aic_common_set_priority(intspec[2], &smr); irq_reg_writel(gc, smr, AT91_AIC_SMR(*out_hwirq)); - irq_gc_unlock(gc); + irq_gc_unlock_irqrestore(gc, flags); return ret; } diff --git a/drivers/irqchip/irq-atmel-aic5.c b/drivers/irqchip/irq-atmel-aic5.c index 4f0d068e1abe..2a624d87a035 100644 --- a/drivers/irqchip/irq-atmel-aic5.c +++ b/drivers/irqchip/irq-atmel-aic5.c @@ -258,6 +258,7 @@ static int aic5_irq_domain_xlate(struct irq_domain *d, unsigned int *out_type) { struct irq_chip_generic *bgc = irq_get_domain_generic_chip(d, 0); + unsigned long flags; unsigned smr; int ret; @@ -269,12 +270,12 @@ static int aic5_irq_domain_xlate(struct irq_domain *d, if (ret) return ret; - irq_gc_lock(bgc); + irq_gc_lock_irqsave(bgc, flags); irq_reg_writel(bgc, *out_hwirq, AT91_AIC5_SSR); smr = irq_reg_readl(bgc, AT91_AIC5_SMR); aic_common_set_priority(intspec[2], &smr); irq_reg_writel(bgc, smr, AT91_AIC5_SMR); - irq_gc_unlock(bgc); + irq_gc_unlock_irqrestore(bgc, flags); return ret; } -- 2.7.4