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 ESMTPS id 2E7A9B6F80 for ; Thu, 1 Sep 2011 07:33:16 +1000 (EST) Subject: Re: [v3 PATCH 1/1] booke/kprobe: make program exception to use one dedicated exception stack From: Benjamin Herrenschmidt To: "tiejun.chen" In-Reply-To: <4E5DFC41.7030606@windriver.com> References: <1310383915-30543-1-git-send-email-tiejun.chen@windriver.com> <4E1FCFEF.7070702@windriver.com> <20110715134232.56373e03@schlenkerla.am.freescale.net> <82C960D7DF4A1F47B94FC1C67A29BEE384D577@ALA-MBA.corp.ad.wrs.com> <20110718105627.245c9fa4@schlenkerla.am.freescale.net> <4E2561F0.5040701@windriver.com> <1314683064.2488.76.camel@pasglop> <4E5DFC41.7030606@windriver.com> Content-Type: text/plain; charset="UTF-8" Date: Thu, 01 Sep 2011 07:32:59 +1000 Message-ID: <1314826379.2488.151.camel@pasglop> Mime-Version: 1.0 Cc: Scott Wood , "linuxppc-dev@ozlabs.org" List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Wed, 2011-08-31 at 17:17 +0800, tiejun.chen wrote: > > It sounds hackish but it makes it easier to fix everybody at once, there > > are "issues" with changing stacks especially on ppc64 and it would > > definitely be affected as well if the stack frame created is larger than > > our gap. > > If we provide another exception stack like we did debug exception on ppc64, are > there those "issues" you said? Actually if we allocate it like the irq stacks, we should be ok, but that's yet another 16K per CPU that needs to be covered by the first segment, nasty.... In any case, please try to come up with a patch that covers all variants. Cheers, Ben.