From mboxrd@z Thu Jan 1 00:00:00 1970 From: will.deacon@arm.com (Will Deacon) Date: Fri, 15 Apr 2016 15:12:42 +0100 Subject: [PATCH 4/5] arm64: Verify CPU errata work arounds on hotplugged CPU In-Reply-To: <5710F653.5070301@arm.com> References: <1459941854-5190-1-git-send-email-suzuki.poulose@arm.com> <1459941854-5190-5-git-send-email-suzuki.poulose@arm.com> <20160414173948.GO4584@arm.com> <570FD817.5050704@arm.com> <5710F653.5070301@arm.com> Message-ID: <20160415141242.GM22906@arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Fri, Apr 15, 2016 at 03:10:27PM +0100, Suzuki K Poulose wrote: > On 14/04/16 18:49, Suzuki K Poulose wrote: > >On 14/04/16 18:39, Will Deacon wrote: > >>On Wed, Apr 06, 2016 at 12:24:13PM +0100, Suzuki K Poulose wrote: > >>>CPU Errata work arounds are detected and applied to the > >>>kernel code at boot time and the data is then freed up. > >>>If a new hotplugged CPU requires a work around which > >>>was not applied at boot time, there is nothing we can > >>>do but simply fail the booting. > >> > >>Hmm, wouldn't it be better not to free the alternative text for errata > >>workarounds instead? > > > >We could. I don't have a strong opinion. If there are no objections, I could > >adopt it. > > The alternatives have been merged to .init by : > > commit 9aa4ec1571da6236 ("arm64: mm: fold alternatives into .init") > > Mark, > > Do you have any concerns on applying alternatives for CPUs turned online later ? > We have to revert the patch above to get going Well, note that I'm only suggesting that we keep the alternatives for CPU errata workarounds. Will From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751375AbcDOOMq (ORCPT ); Fri, 15 Apr 2016 10:12:46 -0400 Received: from foss.arm.com ([217.140.101.70]:49877 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750914AbcDOOMo (ORCPT ); Fri, 15 Apr 2016 10:12:44 -0400 Date: Fri, 15 Apr 2016 15:12:42 +0100 From: Will Deacon To: Suzuki K Poulose Cc: mark.rutland@arm.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, marc.zyngier@arm.com, catalin.marinas@arm.com, Vadim.Lomovtsev@caviumnetworks.com, Andre Przywara Subject: Re: [PATCH 4/5] arm64: Verify CPU errata work arounds on hotplugged CPU Message-ID: <20160415141242.GM22906@arm.com> References: <1459941854-5190-1-git-send-email-suzuki.poulose@arm.com> <1459941854-5190-5-git-send-email-suzuki.poulose@arm.com> <20160414173948.GO4584@arm.com> <570FD817.5050704@arm.com> <5710F653.5070301@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <5710F653.5070301@arm.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Apr 15, 2016 at 03:10:27PM +0100, Suzuki K Poulose wrote: > On 14/04/16 18:49, Suzuki K Poulose wrote: > >On 14/04/16 18:39, Will Deacon wrote: > >>On Wed, Apr 06, 2016 at 12:24:13PM +0100, Suzuki K Poulose wrote: > >>>CPU Errata work arounds are detected and applied to the > >>>kernel code at boot time and the data is then freed up. > >>>If a new hotplugged CPU requires a work around which > >>>was not applied at boot time, there is nothing we can > >>>do but simply fail the booting. > >> > >>Hmm, wouldn't it be better not to free the alternative text for errata > >>workarounds instead? > > > >We could. I don't have a strong opinion. If there are no objections, I could > >adopt it. > > The alternatives have been merged to .init by : > > commit 9aa4ec1571da6236 ("arm64: mm: fold alternatives into .init") > > Mark, > > Do you have any concerns on applying alternatives for CPUs turned online later ? > We have to revert the patch above to get going Well, note that I'm only suggesting that we keep the alternatives for CPU errata workarounds. Will