From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from gate.crashing.org (gate.crashing.org [63.228.1.57]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTP id 8A802DE019 for ; Wed, 5 Mar 2008 19:30:36 +1100 (EST) Subject: Re: [BUG] 2.6.25-rc3-mm1 kernel panic while bootup on powerpc () From: Benjamin Herrenschmidt To: Andrew Morton In-Reply-To: <20080304103350.12d26560.akpm@linux-foundation.org> References: <20080304011928.e8c82c0c.akpm@linux-foundation.org> <47CD4AB3.3080409@linux.vnet.ibm.com> <20778.1204641656@neuling.org> <20080304103350.12d26560.akpm@linux-foundation.org> Content-Type: text/plain Date: Wed, 05 Mar 2008 19:23:40 +1100 Message-Id: <1204705420.21545.192.camel@pasglop> Mime-Version: 1.0 Cc: Matthew Wilcox , linuxppc-dev@ozlabs.org, Michael Neuling , linux-kernel@vger.kernel.org, Kamalesh Babulal Reply-To: benh@kernel.crashing.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Tue, 2008-03-04 at 10:33 -0800, Andrew Morton wrote: > > Are we somehow enabling interrupts before we've setup > ppc_md.get_irq? > > > > Yes, we are - it's the semaphore rewrite which is doing this in > start_kernel(). It's being discussed. > > Enabling interrupts too early on powerpc was discovered to be fatal on > powerpc years ago. It looks like that remains the case. Yes, it is and will probably always be. All that semaphore mucking around that hard-enables interrupts is just asking for trouble (and on more than just powerpc... heh, how do you do if your main interrupt controller hasn't even been initialized yet ?) Ben.