Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756226AbYLPWfQ (ORCPT ); Tue, 16 Dec 2008 17:35:16 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752613AbYLPWfA (ORCPT ); Tue, 16 Dec 2008 17:35:00 -0500 Received: from mx3.mail.elte.hu ([157.181.1.138]:48435 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752594AbYLPWe7 (ORCPT ); Tue, 16 Dec 2008 17:34:59 -0500 Date: Tue, 16 Dec 2008 23:34:26 +0100 From: Ingo Molnar To: Arjan van de Ven Cc: Linus Torvalds , Pekka Enberg , Frans Pop , Eric Anholt , nix.or.die@googlemail.com, linux-kernel@vger.kernel.org, rjw@sisk.pl, Yinghai Lu Subject: Re: Linux 2.6.28-rc8 Message-ID: <20081216223426.GN14787@elte.hu> References: <200812111707.20857.elendil@planet.nl> <20081211163548.GA11859@elte.hu> <20081211203604.GA14817@elte.hu> <84144f020812111246m7f6470f2n8b09283f54ead81@mail.gmail.com> <20081212082456.GA25106@elte.hu> <20081212075746.4ddc9349@infradead.org> <20081213091527.6f8efbc7@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20081213091527.6f8efbc7@infradead.org> User-Agent: Mutt/1.5.18 (2008-05-17) X-ELTE-VirusStatus: clean X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.3 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Arjan van de Ven wrote: > On Fri, 12 Dec 2008 08:11:35 -0800 (PST) > Linus Torvalds wrote: > > > > > > > On Fri, 12 Dec 2008, Arjan van de Ven wrote: > > > > > > another thing we could do is try to only warn if you cross bar > > > boundaries but not if you cross other user-of-the-resource > > > boundaries. > > > > Hmm. We could use the res->flags for this. But I'm not sure non-PCI > > resources fill those in correctly. > > > > A pure "busy" allocation (ie a driver marker) would generally have > > just the IORESOURCE_BUSY bit set, while a real PCI hardware resource > > will have other bits set (ie the IORESOURCE_IO/MEM bits) and not be > > marked BUSY. > > > > Maybe just ignoring resources with BUSY set, as they are driver > > markers rather than actual HW resources. > > something like this: ? okay, i've applied it in the form below, to tip/core/resources. This in combination with the toning down of the messages should do the trick i think. btw., here's a bug that got caught by the sanity checks: | commit d522af581c6abd0e064278345ca638b0553a93fa | Author: Suresh Siddha | Date: Mon Oct 20 17:57:02 2008 -0300 | | V4L/DVB (9356): [PATCH] saa7134: fix resource map sanity check conflict | | Impact: driver could possibly stomp on resources outside of its scope so it's not just nuisance. > Note: having two drivers talk to the same hardware at the same > time is obviously not optimal behavior, but that's a separate story. it will be much more likely to be caught via other misbehavior i guess. Ingo ------------------> >From 3ac52669c7a24b93663acfcab606d1065ed1accd Mon Sep 17 00:00:00 2001 From: Arjan van de Ven Date: Sat, 13 Dec 2008 09:15:27 -0800 Subject: [PATCH] resources: skip sanity check of busy resources Impact: reduce false positives in iomem_map_sanity_check() Some drivers (vesafb) only map/reserve a portion of a resource. If then some other driver comes in and maps the whole resource, the current code WARN_ON's. This is not the intent of the checks in iomem_map_sanity_check(); rather these checks want to warn when crossing *hardware* resources only. This patch skips BUSY resources as suggested by Linus. Note: having two drivers talk to the same hardware at the same time is obviously not optimal behavior, but that's a separate story. Signed-off-by: Arjan van de Ven Signed-off-by: Ingo Molnar --- kernel/resource.c | 9 +++++++++ 1 files changed, 9 insertions(+), 0 deletions(-) diff --git a/kernel/resource.c b/kernel/resource.c index 4337063..e633106 100644 --- a/kernel/resource.c +++ b/kernel/resource.c @@ -853,6 +853,15 @@ int iomem_map_sanity_check(resource_size_t addr, unsigned long size) if (PFN_DOWN(p->start) <= PFN_DOWN(addr) && PFN_DOWN(p->end) >= PFN_DOWN(addr + size - 1)) continue; + /* + * 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) + */ + if (p->flags & IORESOURCE_BUSY) + continue; + printk(KERN_WARNING "resource map sanity check conflict: " "0x%llx 0x%llx 0x%llx 0x%llx %s\n", (unsigned long long)addr, -- 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/