From mboxrd@z Thu Jan 1 00:00:00 1970 From: Catalin Marinas Subject: Re: [PATH V2 5/6] arm64: mm: Enable HAVE_RCU_TABLE_FREE logic Date: Wed, 27 Aug 2014 11:48:41 +0100 Message-ID: <20140827104840.GH6968@arm.com> References: <1408635812-31584-1-git-send-email-steve.capper@linaro.org> <1408635812-31584-6-git-send-email-steve.capper@linaro.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <1408635812-31584-6-git-send-email-steve.capper@linaro.org> Sender: owner-linux-mm@kvack.org To: Steve Capper Cc: "linux-arm-kernel@lists.infradead.org" , "linux@arm.linux.org.uk" , "linux-arch@vger.kernel.org" , "linux-mm@kvack.org" , Will Deacon , "gary.robertson@linaro.org" , "christoffer.dall@linaro.org" , "peterz@infradead.org" , "anders.roxell@linaro.org" , "akpm@linux-foundation.org" , "dann.frazier@canonical.com" , Mark Rutland , "mgorman@suse.de" List-Id: linux-arch.vger.kernel.org On Thu, Aug 21, 2014 at 04:43:31PM +0100, Steve Capper wrote: > In order to implement fast_get_user_pages we need to ensure that the > page table walker is protected from page table pages being freed from > under it. > > This patch enables HAVE_RCU_TABLE_FREE, any page table pages belonging > to address spaces with multiple users will be call_rcu_sched freed. > Meaning that disabling interrupts will block the free and protect the > fast gup page walker. > > Signed-off-by: Steve Capper I'm happy to take this patch independently of this series. But if the whole series goes in via some other tree (mm): Acked-by: Catalin Marinas -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from fw-tnat.austin.arm.com ([217.140.110.23]:42222 "EHLO collaborate-mta1.arm.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S932539AbaH0KtP (ORCPT ); Wed, 27 Aug 2014 06:49:15 -0400 Date: Wed, 27 Aug 2014 11:48:41 +0100 From: Catalin Marinas Subject: Re: [PATH V2 5/6] arm64: mm: Enable HAVE_RCU_TABLE_FREE logic Message-ID: <20140827104840.GH6968@arm.com> References: <1408635812-31584-1-git-send-email-steve.capper@linaro.org> <1408635812-31584-6-git-send-email-steve.capper@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1408635812-31584-6-git-send-email-steve.capper@linaro.org> Sender: linux-arch-owner@vger.kernel.org List-ID: To: Steve Capper Cc: "linux-arm-kernel@lists.infradead.org" , "linux@arm.linux.org.uk" , "linux-arch@vger.kernel.org" , "linux-mm@kvack.org" , Will Deacon , "gary.robertson@linaro.org" , "christoffer.dall@linaro.org" , "peterz@infradead.org" , "anders.roxell@linaro.org" , "akpm@linux-foundation.org" , "dann.frazier@canonical.com" , Mark Rutland , "mgorman@suse.de" Message-ID: <20140827104841.6zPwE95uHA6V2P7eC0PJlwUG-HxLVE8OR_Onw3TsZPE@z> On Thu, Aug 21, 2014 at 04:43:31PM +0100, Steve Capper wrote: > In order to implement fast_get_user_pages we need to ensure that the > page table walker is protected from page table pages being freed from > under it. > > This patch enables HAVE_RCU_TABLE_FREE, any page table pages belonging > to address spaces with multiple users will be call_rcu_sched freed. > Meaning that disabling interrupts will block the free and protect the > fast gup page walker. > > Signed-off-by: Steve Capper I'm happy to take this patch independently of this series. But if the whole series goes in via some other tree (mm): Acked-by: Catalin Marinas From mboxrd@z Thu Jan 1 00:00:00 1970 From: catalin.marinas@arm.com (Catalin Marinas) Date: Wed, 27 Aug 2014 11:48:41 +0100 Subject: [PATH V2 5/6] arm64: mm: Enable HAVE_RCU_TABLE_FREE logic In-Reply-To: <1408635812-31584-6-git-send-email-steve.capper@linaro.org> References: <1408635812-31584-1-git-send-email-steve.capper@linaro.org> <1408635812-31584-6-git-send-email-steve.capper@linaro.org> Message-ID: <20140827104840.GH6968@arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Thu, Aug 21, 2014 at 04:43:31PM +0100, Steve Capper wrote: > In order to implement fast_get_user_pages we need to ensure that the > page table walker is protected from page table pages being freed from > under it. > > This patch enables HAVE_RCU_TABLE_FREE, any page table pages belonging > to address spaces with multiple users will be call_rcu_sched freed. > Meaning that disabling interrupts will block the free and protect the > fast gup page walker. > > Signed-off-by: Steve Capper I'm happy to take this patch independently of this series. But if the whole series goes in via some other tree (mm): Acked-by: Catalin Marinas