Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753851Ab1FBRzS (ORCPT ); Thu, 2 Jun 2011 13:55:18 -0400 Received: from opensource.wolfsonmicro.com ([80.75.67.52]:56977 "EHLO opensource2.wolfsonmicro.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752660Ab1FBRzQ (ORCPT ); Thu, 2 Jun 2011 13:55:16 -0400 From: Mark Brown To: Thomas Gleixner Cc: linux-kernel@vger.kernel.org, Mark Brown Subject: [PATCH] genirq: Ensure we locate the passed IRQ in irq_alloc_descs() Date: Thu, 2 Jun 2011 18:55:13 +0100 Message-Id: <1307037313-15733-1-git-send-email-broonie@opensource.wolfsonmicro.com> X-Mailer: git-send-email 1.7.5.3 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1600 Lines: 43 When irq_alloc_descs() is called with no base IRQ specified then it will search for a range of IRQs starting from a specified base address. In the case where an IRQ is specified it still does this search in order to ensure that none of the requested range is already allocated and it still uses the from parameter to specify the base for the search. This means that in the case where a base is specified but from is zero (which is reasonable as any IRQ number is in the range specified by a zero from) the function will get confused and try to allocate the first suitably sized block of free IRQs it finds. Instead use a specified IRQ as the base address for the search, and insist that any from that is specified can support that IRQ. Signed-off-by: Mark Brown --- kernel/irq/irqdesc.c | 6 ++++++ 1 files changed, 6 insertions(+), 0 deletions(-) diff --git a/kernel/irq/irqdesc.c b/kernel/irq/irqdesc.c index 886e803..bb53d6c 100644 --- a/kernel/irq/irqdesc.c +++ b/kernel/irq/irqdesc.c @@ -346,6 +346,12 @@ irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node) if (!cnt) return -EINVAL; + if (irq >= 0) { + if (from > irq) + return -EINVAL; + from = irq; + } + mutex_lock(&sparse_irq_lock); start = bitmap_find_next_zero_area(allocated_irqs, IRQ_BITMAP_BITS, -- 1.7.5.3 -- 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/