From mboxrd@z Thu Jan 1 00:00:00 1970 From: Toshi Kani Subject: [PATCH 1/3] resource: Make __request_region to inherit from immediate parent Date: Tue, 2 Feb 2016 11:55:09 -0700 Message-ID: <1454439311-23690-2-git-send-email-toshi.kani@hpe.com> References: <1454439311-23690-1-git-send-email-toshi.kani@hpe.com> Return-path: In-Reply-To: <1454439311-23690-1-git-send-email-toshi.kani@hpe.com> Sender: linux-kernel-owner@vger.kernel.org To: mingo@kernel.org, bp@suse.de, dan.j.williams@intel.com, rjw@rjwysocki.net, akpm@linux-foundation.org Cc: linux-nvdimm@lists.01.org, linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org, Toshi Kani List-Id: linux-acpi@vger.kernel.org __request_region() sets 'flags' from a given 'parent' to inherit its attribute. When a target resource has conflict, this function inserts a resource entry under the conflicted entry by updating 'parent'. In this case, the new resource entry needs to inherit attribute from the updated parent. For instance, request_mem_region() calls __request_region() with 'parent' set to &iomem_resource, which is the root entry of the whole iomem range. When this request results in inserting a new entry "new" under "DEV-A", "new" needs to inherit from the immediate parent "DEV-A" as it holds specific attribute for the range. root (&iomem_resource) : + "DEV-A" + "new" Change __request_region() to set 'flags' and 'desc' of a new entry from the immediate parent. Signed-off-by: Toshi Kani Cc: Ingo Molnar Cc: Borislav Petkov Cc: Andrew Morton Cc: Dan Williams --- kernel/resource.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/kernel/resource.c b/kernel/resource.c index 4983430..9df79ff 100644 --- a/kernel/resource.c +++ b/kernel/resource.c @@ -1085,15 +1085,16 @@ struct resource * __request_region(struct resource *parent, res->name = name; res->start = start; res->end = start + n - 1; - res->flags = resource_type(parent) | resource_ext_type(parent); - res->flags |= IORESOURCE_BUSY | flags; - res->desc = IORES_DESC_NONE; write_lock(&resource_lock); for (;;) { struct resource *conflict; + res->flags = resource_type(parent) | resource_ext_type(parent); + res->flags |= IORESOURCE_BUSY | flags; + res->desc = parent->desc; + conflict = __request_resource(parent, res); if (!conflict) break;