Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753551Ab3JBOlU (ORCPT ); Wed, 2 Oct 2013 10:41:20 -0400 Received: from mail-ee0-f54.google.com ([74.125.83.54]:54729 "EHLO mail-ee0-f54.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753104Ab3JBOlR (ORCPT ); Wed, 2 Oct 2013 10:41:17 -0400 From: David Herrmann To: linux-kernel@vger.kernel.org Cc: Tom Gundersen , Pavel Roskin , "H. Peter Anvin" , Ingo Molnar , x86@kernel.org, David Herrmann Subject: [PATCH] x86: sysfb: mark simplefb resources as BUSY Date: Wed, 2 Oct 2013 16:41:04 +0200 Message-Id: <1380724864-1757-1-git-send-email-dh.herrmann@gmail.com> X-Mailer: git-send-email 1.8.4 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2951 Lines: 76 IORESOURCE_BUSY is used to mark temporary driver mem-resources instead of global regions. This suppresses warnings if regions overlap with a region marked as BUSY. This was always the case for VESA/VGA/EFI framebuffer regions so do the same for simplefb regions. The reason we do this is to allow device handover to real GPU drivers like i915/radeon/nouveau which get the same regions via PCI BARs. Maybe at some point we will be able to unregister platform devices properly during the handover. In this case the simplefb region would get removed before the new region is created. However, this is currently not the case and would require rather huge changes in remove_conflicting_framebuffers(). Add the BUSY marker now and try to eventually rewrite the handover for a next release. Also see kernel/resource.c for more information: /* * if a resource is "BUSY", it's not a hardware resource * but a driver mapping of such a resource; we don't want * to warn for those; some drivers legitimately map only * partial hardware resources. (example: vesafb) */ This suppresses warnings like: ------------[ cut here ]------------ WARNING: CPU: 2 PID: 199 at arch/x86/mm/ioremap.c:171 __ioremap_caller+0x2e3/0x390() Info: mapping multiple BARs. Your kernel is fine. Call Trace: dump_stack+0x54/0x8d warn_slowpath_common+0x7d/0xa0 warn_slowpath_fmt+0x4c/0x50 iomem_map_sanity_check+0xac/0xe0 __ioremap_caller+0x2e3/0x390 ioremap_wc+0x32/0x40 i915_driver_load+0x670/0xf50 [i915] ... Reported-by: Tom Gundersen Signed-off-by: David Herrmann Tested-by: Tom Gundersen Tested-by: Pavel Roskin --- Hi Sorry for the delay, but I was in the US for the last 2 weeks and this is really no major issue, just suppresses a warning that says "Your kernel is fine". Anyhow, thanks to Tom and Pavel for reporting and testing this! This is targeted at 3.12-rc4 as bugfix. I think it's still early/mid rc-stage and is a one-line patch so it should be fine, right? Thanks David arch/x86/kernel/sysfb_simplefb.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/kernel/sysfb_simplefb.c b/arch/x86/kernel/sysfb_simplefb.c index 22513e9..b7bb615 100644 --- a/arch/x86/kernel/sysfb_simplefb.c +++ b/arch/x86/kernel/sysfb_simplefb.c @@ -79,7 +79,7 @@ __init int create_simplefb(const struct screen_info *si, /* setup IORESOURCE_MEM as framebuffer memory */ memset(&res, 0, sizeof(res)); - res.flags = IORESOURCE_MEM; + res.flags = IORESOURCE_MEM | IORESOURCE_BUSY; res.name = simplefb_resname; res.start = si->lfb_base; res.end = si->lfb_base + len - 1; -- 1.8.4 -- 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/