Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756581AbbGPXYi (ORCPT ); Thu, 16 Jul 2015 19:24:38 -0400 Received: from g4t3426.houston.hp.com ([15.201.208.54]:45299 "EHLO g4t3426.houston.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756403AbbGPXYY (ORCPT ); Thu, 16 Jul 2015 19:24:24 -0400 From: Toshi Kani To: tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com, akpm@linux-foundation.org Cc: travis@sgi.com, roland@purestorage.com, dan.j.williams@intel.com, mcgrof@suse.com, x86@kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Toshi Kani Subject: [PATCH RESEND 3/3] mm: Fix bugs in region_is_ram() Date: Thu, 16 Jul 2015 17:23:16 -0600 Message-Id: <1437088996-28511-4-git-send-email-toshi.kani@hp.com> X-Mailer: git-send-email 2.4.3 In-Reply-To: <1437088996-28511-1-git-send-email-toshi.kani@hp.com> References: <1437088996-28511-1-git-send-email-toshi.kani@hp.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1892 Lines: 56 region_is_ram() looks up the iomem_resource table to check if a target range is in RAM. However, it always returns with -1 due to invalid range checks. It always breaks the loop at the first entry of the table. Another issue is that it compares p->flags and flags, but it always fails. The flags is declared as int, which makes it as a negative value with IORESOURCE_BUSY (0x80000000) set while p->flags is unsigned long. Fix the range check and flags so that region_is_ram() works as advertised. Signed-off-by: Toshi Kani Cc: Mike Travis Cc: Luis R. Rodriguez Cc: Dan Williams Cc: Andrew Morton --- kernel/resource.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/kernel/resource.c b/kernel/resource.c index 90552aa..fed052a 100644 --- a/kernel/resource.c +++ b/kernel/resource.c @@ -504,13 +504,13 @@ int region_is_ram(resource_size_t start, unsigned long size) { struct resource *p; resource_size_t end = start + size - 1; - int flags = IORESOURCE_MEM | IORESOURCE_BUSY; + unsigned long flags = IORESOURCE_MEM | IORESOURCE_BUSY; const char *name = "System RAM"; int ret = -1; read_lock(&resource_lock); for (p = iomem_resource.child; p ; p = p->sibling) { - if (end < p->start) + if (p->end < start) continue; if (p->start <= start && end <= p->end) { @@ -521,7 +521,7 @@ int region_is_ram(resource_size_t start, unsigned long size) ret = 1; break; } - if (p->end < start) + if (end < p->start) break; /* not found */ } read_unlock(&resource_lock); -- 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/