From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Thu, 12 Feb 2004 09:40:09 -0500 (EST) From: Zwane Mwaikambo Subject: Re: 2.6.3-rc2-mm1 In-Reply-To: <20040212040910.3de346d4.akpm@osdl.org> Message-ID: References: <20040212015710.3b0dee67.akpm@osdl.org> <20040212031322.742b29e7.akpm@osdl.org> <20040212115718.GF25922@krispykreme> <20040212040910.3de346d4.akpm@osdl.org> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org Return-Path: To: Andrew Morton Cc: Anton Blanchard , linux-kernel@vger.kernel.org, linux-mm@kvack.org List-ID: On Thu, 12 Feb 2004, Andrew Morton wrote: > Anton Blanchard wrote: > > > > > > > This kernel and also 2.6.3-rc1-mm1 have a nasty bug which causes > > > current->preempt_count to be decremented by one on each hard IRQ. It > > > manifests as a BUG() in the slab code early in boot. > > > > > > Disabling CONFIG_DEBUG_SPINLOCK_SLEEP will fix this up. Do not use this > > > feature on ia32, for it is bust. > > > > A few questions spring to mind. Like who wrote that dodgy patch? > > The dog wrote my homework? I've not managed to trigger this one CONFIG_DEBUG_KERNEL=y CONFIG_DEBUG_STACKOVERFLOW=y # CONFIG_DEBUG_SLAB is not set CONFIG_DEBUG_IOVIRT=y CONFIG_DEBUG_SPINLOCK=y CONFIG_DEBUG_PAGEALLOC=y CONFIG_DEBUG_HIGHMEM=y CONFIG_DEBUG_INFO=y CONFIG_DEBUG_SPINLOCK_SLEEP=y > > And any ideas how said person (who will remain nameless) broke ia32? > > Not really. I spent a couple of hours debugging the darn thing, then gave > up and used binary search to find the offending patch. > > > > include/asm-i386/hardirq.h:IRQ_EXIT_OFFSET needs treatment, I bet. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: aart@kvack.org