Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753367AbbETMM7 (ORCPT ); Wed, 20 May 2015 08:12:59 -0400 Received: from foss.arm.com ([217.140.101.70]:37949 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752324AbbETMM4 (ORCPT ); Wed, 20 May 2015 08:12:56 -0400 Date: Wed, 20 May 2015 13:14:38 +0100 From: Marc Zyngier To: Robert Richter Cc: Thomas Gleixner , Jason Cooper , Tirumalesh Chalamarla , Radha Mohan Chintakuntla , "linux-kernel@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , Robert Richter Subject: Re: [PATCH 2/4] arm64: gicv3: its: Add range check for number of allocated pages Message-ID: <20150520131438.6e94e661@why.wild-wind.fr.eu.org> In-Reply-To: <1430686172-18222-3-git-send-email-rric@kernel.org> References: <1430686172-18222-1-git-send-email-rric@kernel.org> <1430686172-18222-3-git-send-email-rric@kernel.org> Organization: ARM Ltd X-Mailer: Claws Mail 3.11.1 (GTK+ 2.24.25; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2802 Lines: 81 On Sun, 3 May 2015 21:49:30 +0100 Robert Richter wrote: > From: Robert Richter > > The number of pages for the its table may exceed the maximum of 256. > Adding a range check and limitting the number to its maximum. > > Based on a patch from Tirumalesh Chalamarla . > > Signed-off-by: Robert Richter Looks good to me. Reviewed-by: Marc Zyngier M. > --- > drivers/irqchip/irq-gic-v3-its.c | 11 ++++++++++- > include/linux/irqchip/arm-gic-v3.h | 1 + > 2 files changed, 11 insertions(+), 1 deletion(-) > > diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c > index e30b4de04c6c..a2619a1d5bb3 100644 > --- a/drivers/irqchip/irq-gic-v3-its.c > +++ b/drivers/irqchip/irq-gic-v3-its.c > @@ -810,6 +810,7 @@ static int its_alloc_tables(struct its_node *its) > u64 entry_size = GITS_BASER_ENTRY_SIZE(val); > int order = get_order(psz); > int alloc_size; > + int alloc_pages; > u64 tmp; > void *base; > > @@ -837,6 +838,14 @@ static int its_alloc_tables(struct its_node *its) > } > > alloc_size = (1 << order) * PAGE_SIZE; > + alloc_pages = (alloc_size / psz); > + if (alloc_pages > GITS_BASER_PAGES_MAX) { > + alloc_pages = GITS_BASER_PAGES_MAX; > + order = get_order(GITS_BASER_PAGES_MAX * psz); > + pr_warn("%s: Device Table too large, reduce its page order to %u (%u pages)\n", > + its->msi_chip.of_node->full_name, order, alloc_pages); > + } > + > base = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, order); > if (!base) { > err = -ENOMEM; > @@ -865,7 +874,7 @@ static int its_alloc_tables(struct its_node *its) > break; > } > > - val |= (alloc_size / psz) - 1; > + val |= alloc_pages - 1; > > writeq_relaxed(val, its->base + GITS_BASER + i * 8); > tmp = readq_relaxed(its->base + GITS_BASER + i * 8); > diff --git a/include/linux/irqchip/arm-gic-v3.h b/include/linux/irqchip/arm-gic-v3.h > index ffbc034c8810..f28da189c4aa 100644 > --- a/include/linux/irqchip/arm-gic-v3.h > +++ b/include/linux/irqchip/arm-gic-v3.h > @@ -229,6 +229,7 @@ > #define GITS_BASER_PAGE_SIZE_16K (1UL << GITS_BASER_PAGE_SIZE_SHIFT) > #define GITS_BASER_PAGE_SIZE_64K (2UL << GITS_BASER_PAGE_SIZE_SHIFT) > #define GITS_BASER_PAGE_SIZE_MASK (3UL << GITS_BASER_PAGE_SIZE_SHIFT) > +#define GITS_BASER_PAGES_MAX 256 > > #define GITS_BASER_TYPE_NONE 0 > #define GITS_BASER_TYPE_DEVICE 1 -- Without deviation from the norm, progress is not possible. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/