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 622FEDDE3F for ; Sat, 27 Oct 2007 14:19:40 +1000 (EST) Subject: Re: [PATCH] [Powerpc] fix switch_slb handling of 1T ESID values From: Benjamin Herrenschmidt To: Will Schmidt In-Reply-To: <20071026204641.25514.45178.stgit@farscape.rchland.ibm.com> References: <20071026204641.25514.45178.stgit@farscape.rchland.ibm.com> Content-Type: text/plain Date: Sat, 27 Oct 2007 14:19:31 +1000 Message-Id: <1193458771.18243.55.camel@pasglop> Mime-Version: 1.0 Cc: linuxppc-dev@ozlabs.org, paulus@samba.org 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 Fri, 2007-10-26 at 15:46 -0500, Will Schmidt wrote: > [Powerpc] fix switch_slb handling of 1T ESID values > > Now that we have 1TB segment size support, we need to be using the > GET_ESID_1T macro when comparing ESID values for pc,stack, and > unmapped_base within switch_slb() when we're on a CPU that supports it. > > This also happens to fix a duplicate-slb-entry inspired machine-check > exception I was seeing when trying to run java on a power6 partition. > > Tested on power6 and power5. > > Signed-Off-By: Will Schmidt Good catch ! A minor comment is maybe you could factor out the code better doing something like a ESID_COMPARE() macro ? > --- > > There is a similar bit of code in stab.c switch_stab(). Should this change also be made there? > --- There is no machine that does stab and 1T segments. Ben. > > arch/powerpc/mm/slb.c | 19 ++++++++++++++----- > 1 files changed, 14 insertions(+), 5 deletions(-) > > > diff --git a/arch/powerpc/mm/slb.c b/arch/powerpc/mm/slb.c > index bbd2c51..0c527d7 100644 > --- a/arch/powerpc/mm/slb.c > +++ b/arch/powerpc/mm/slb.c > @@ -193,16 +193,25 @@ void switch_slb(struct task_struct *tsk, struct mm_struct *mm) > return; > slb_allocate(pc); > > - if (GET_ESID(pc) == GET_ESID(stack)) > - return; > + if (cpu_has_feature(CPU_FTR_1T_SEGMENT)) { > + if (GET_ESID_1T(pc) == GET_ESID_1T(stack)) > + return; > + } else > + if (GET_ESID(pc) == GET_ESID(stack)) > + return; > > if (is_kernel_addr(stack)) > return; > slb_allocate(stack); > > - if ((GET_ESID(pc) == GET_ESID(unmapped_base)) > - || (GET_ESID(stack) == GET_ESID(unmapped_base))) > - return; > + if (cpu_has_feature(CPU_FTR_1T_SEGMENT)) { > + if ((GET_ESID_1T(pc) == GET_ESID_1T(unmapped_base)) > + || (GET_ESID_1T(stack) == GET_ESID_1T(unmapped_base))) > + return; > + } else > + if ((GET_ESID(pc) == GET_ESID(unmapped_base)) > + || (GET_ESID(stack) == GET_ESID(unmapped_base))) > + return; > > if (is_kernel_addr(unmapped_base)) > return; > > > _______________________________________________ > Linuxppc-dev mailing list > Linuxppc-dev@ozlabs.org > https://ozlabs.org/mailman/listinfo/linuxppc-dev