From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ozlabs.org (ozlabs.org [203.10.76.45]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "mx.ozlabs.org", Issuer "CA Cert Signing Authority" (verified OK)) by bilbo.ozlabs.org (Postfix) with ESMTPS id 7F5F3B7067 for ; Thu, 6 Aug 2009 16:42:03 +1000 (EST) Received: from bombadil.infradead.org (bombadil.infradead.org [18.85.46.34]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 301DDDDD0C for ; Thu, 6 Aug 2009 16:42:02 +1000 (EST) Subject: Re: [PATCH] powerpc/perfctr: Check oprofile_cpu_type for NULL before using it From: David Woodhouse To: Benjamin Herrenschmidt In-Reply-To: <1249531356.18245.73.camel@pasglop> References: <1249531356.18245.73.camel@pasglop> Content-Type: text/plain Date: Thu, 06 Aug 2009 07:41:50 +0100 Message-Id: <1249540910.23206.67.camel@macbook.infradead.org> Mime-Version: 1.0 Cc: linuxppc-dev list , Ingo Molnar , Paul Mackerras List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Thu, 2009-08-06 at 14:02 +1000, Benjamin Herrenschmidt wrote: > If the current CPU doesn't support performance counters, > cur_cpu_spec->oprofile_cpu_type can be NULL. The current > perfctr modules don't test for that case and would thus > crash. It can't actually be NULL on a 64-bit CPU; all 64-bit CPUs in the table have ->oprofile_cpu_type set. Of course, adding the check probably makes sense anyway. -- David Woodhouse Open Source Technology Centre David.Woodhouse@intel.com Intel Corporation