From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752251AbbLCSPn (ORCPT ); Thu, 3 Dec 2015 13:15:43 -0500 Received: from mail-bn1bon0088.outbound.protection.outlook.com ([157.56.111.88]:4043 "EHLO na01-bn1-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751763AbbLCSPm (ORCPT ); Thu, 3 Dec 2015 13:15:42 -0500 Authentication-Results: spf=none (sender IP is ) smtp.mailfrom=Yuri.Norov@caviumnetworks.com; Date: Thu, 3 Dec 2015 21:14:41 +0300 From: Yury Norov To: Catalin Marinas CC: Arnd Bergmann , , , , , , , , , , , , , , , , Subject: Re: [PATCH v6 14/19] arm64:ilp32: add sys_ilp32.c and a separate table (in entry.S) to use it Message-ID: <20151203181441.GA16808@yury-N73SV> References: <1447795019-30176-1-git-send-email-ynorov@caviumnetworks.com> <1447795019-30176-15-git-send-email-ynorov@caviumnetworks.com> <3754277.KmO9Nk3XLD@wuerfel> <20151201212904.GA14442@yury-N73SV> <20151203174708.GO10747@e104818-lin.cambridge.arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <20151203174708.GO10747@e104818-lin.cambridge.arm.com> User-Agent: Mutt/1.5.23 (2014-03-12) X-Originating-IP: [95.143.213.120] X-ClientProxiedBy: VI1PR06CA0006.eurprd06.prod.outlook.com (25.162.116.144) To CO2PR07MB618.namprd07.prod.outlook.com (10.141.228.149) X-Microsoft-Exchange-Diagnostics: 1;CO2PR07MB618;2:BxDNf1VC1PFp9W9xKxHVns+aPBARue3DOehdhqiPh3Uc0vdU6Fn0Y7XNGXr3N8CdYUZXtkeC6IGbbcUlw2ms9ZNtWZ4FB/yE+Xg8WK91/GbSRrscueMZevwIboEk338t2QlMqzZxvvaE54I1a9KZ7g==;3:oVZQCIqAI+TyFJ7T+PBERfrBLCpJvWv76QuFeuN1YXdoJsegfyEjFLrLDdRVEUT02Yq7UMECCGkLreBcw0gSU9o/vSf6LvMsr3t8tgFN7e+a5hGvg2TC4oXBLqj9znqM;25:A/d3MB3/ZPB82/4mVuMI+zvCZxTjqamQHwGHv6cA8vmBXY68eGnH7Dz9pSbHVBIBCXzDXys5J+VPL8uZ4sfCuTIstkm+gI/IFCaO/yGidNhjCY85UcWJrDQZeqogjaXb+B61024aqvyTHPEg7zI8BqVS7cNHXSdi/fPGnRSYHXtgg+Hw35Z70I1GhE6zfvueZ4w5L6Ta7ug7JZMRUKi24MQLgqpLv2+kmLJA/DnbJt5vcmiHuHHvmfVXoHO5efJ49JJQIm6HNF5vFmyry9ROVA== X-Microsoft-Antispam: UriScan:;BCL:0;PCL:0;RULEID:;SRVR:CO2PR07MB618; X-Microsoft-Exchange-Diagnostics: 1;CO2PR07MB618;20: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 X-Microsoft-Antispam-PRVS: X-Exchange-Antispam-Report-Test: UriScan:; X-Exchange-Antispam-Report-CFA-Test: BCL:0;PCL:0;RULEID:(601004)(2401047)(5005006)(8121501046)(520078)(10201501046)(3002001);SRVR:CO2PR07MB618;BCL:0;PCL:0;RULEID:;SRVR:CO2PR07MB618; X-Microsoft-Exchange-Diagnostics: 1;CO2PR07MB618;4:qWG5ahAdzhTykD7beaYDX7i99LnW4Q/+5RZsh4V5VMFuTrbLvUhT9kOHBh3lhZ3yj6vzjUDgO+VAdwg+EBLPiCUxnCCrA3YGPYuwGzIIbdoPAiXWKl55E3ncYcWnDbBKObzXCqpWQR2lPK914IpDcA13EpNE2sfnzQ9at/HzAHADjbas/aZJaWWHmFyG7gnOBP9bWWVV560u261O1bQNOv7GnDk3GGdI4P/GZw3e9cw09bVmoR8JFTYne/SbKIk2Bt0w7rA9vC9TABjgWD/zy4s01rX5hPLZXiwYv4CIloZvji8Ymj4r7qs4WrOiYyM2qtLemF3MBYzdwrhSE/Husre+8K/VNrkBNbJlbwvC4jUyykhj41TmdzajIjo7slrI X-Forefront-PRVS: 077929D941 X-Forefront-Antispam-Report: SFV:NSPM;SFS:(10009020)(6009001)(6069001)(199003)(24454002)(189002)(83506001)(97736004)(4001350100001)(122386002)(81156007)(93886004)(87976001)(40100003)(42186005)(5008740100001)(66066001)(47776003)(105586002)(46406003)(5001960100002)(110136002)(106356001)(189998001)(76506005)(50466002)(101416001)(76176999)(1096002)(19580395003)(97756001)(54356999)(1076002)(6116002)(3846002)(586003)(92566002)(23726003)(33716001)(5004730100002)(33656002)(50986999)(2950100001)(77096005)(5890100001)(15975445007);DIR:OUT;SFP:1101;SCL:1;SRVR:CO2PR07MB618;H:localhost;FPR:;SPF:None;PTR:InfoNoRecords;A:1;MX:1;LANG:en; X-Microsoft-Exchange-Diagnostics: =?us-ascii?Q?1;CO2PR07MB618;23:nDmXU8iDaDcxQGUairyyWKarBUifIFO2kWP8iEuEmL?= =?us-ascii?Q?poNrZeRf0I2sy2AI9u8HxsZ9zmMRil/Ni7QNgKFVqrG3NNmuuvojM5+4GGRx?= =?us-ascii?Q?tEas90tTog9J8s8hUg3lYjNM73m2xrrTeVsmex8/uXqt5XPPl9Dgr+TojNZc?= =?us-ascii?Q?fZIIt57PToynpaopzaYJ0+erj9upCoUcDI7L6GYTGfxmMIMj0LyKDtIDwL0p?= =?us-ascii?Q?uIQmhZg5bgufJgiGAbGVE76NMqxST9lcy5ZniIw8ccIWZjXuA/YN7oxYl4FP?= =?us-ascii?Q?LqYctq8NliKfBV2A9wEaTAJn5Sf8WAuPqD1QObz65JtKsRekSHAO+npjQncN?= =?us-ascii?Q?+gT5Hn91o1NxTNfHMU9kIdgGsYDcDzNcV5jQm8KZaXcrDonkZ/9w6Lw941vb?= =?us-ascii?Q?sn282iB9L3Q3G1xh9W5sg+jaSkoP4SYIPduLX/XWmsLuStgJnOX2vwT3VWIo?= =?us-ascii?Q?pS7Lxqneu8bAXNbuihWkfVkDPwL9gn5H6RLGw1b9gBpkch/7CJzUOJtad8FF?= =?us-ascii?Q?IgTkHU58fnUbhq9thxPX4nkt4gUPHiMjKeGhV7uFJpmX5z66VwoV3oT32C0Z?= =?us-ascii?Q?8ZzLi2EPhg/leILWA4Bhk7BM1klHfsnkCtzwr2O10mb/Az+WtXRS9M5QKE96?= =?us-ascii?Q?2N6IL30P3l1WoLNg+FXSC3ehgTlsdaMH6jq4T9fhUy18KCh4gFnCWJcDvnaL?= =?us-ascii?Q?Vx3pnh+gzq4hy/xoumSIWyaXNAbNLIadpxQ2FWle3KVELIR+luY8m8W9Pvs2?= =?us-ascii?Q?7WriruL9EEi3MBgSaJJKb6vJknVUH9v0bIc7R4Wc456qEuLig4mPhzJbLX6c?= =?us-ascii?Q?GHFeg780+V2Guf35Gxy2deAav3hcOzKlN+imglq4pDiXe+osAFjzjjt6ZSRN?= =?us-ascii?Q?1X992T38pkufNqswSpM5DxcCijUAt2EmxyQBMIqCC62Y0O1FiCnzj6PfBdow?= =?us-ascii?Q?sSkZcc9fz+29Py9WWKyDcVQSHVAfFfrCComNYCAuNhYE8I2yvlbJ1+0iskS1?= =?us-ascii?Q?UIVVqooNECQzqTd+Zshc7BJf9z9BRKPPtddGydje1mN/VVEIUSC0RfJSqv1w?= =?us-ascii?Q?yVp4EdpTxe5CjnPrR+JUMW4JiwmnvGW8iM1kcQUYIljV3R6bliZnqY+e2IRS?= =?us-ascii?Q?EPIieesUG2VQOetE5LyKwYOZhAA8lafneptFCPU0hfTTpzcmpljV7Eq4sxZr?= =?us-ascii?Q?fay0L/RsQryEg=3D?= X-Microsoft-Exchange-Diagnostics: 1;CO2PR07MB618;5:CxORFT/UTQBxgVLgOy5fgMSJThEooeiJXks7wWds3gOiPHHNaXaoVYmmzYrmB4PMEOtCmJo1yQ/CDnpD8XbZin9EcrRfaEuHotmC2YvdANkis+xp5wFoiiuuPvbA43A5xuw7XJ9dkXKb0r4GzR/1mA==;24:aYfFJIJuqa2O5eedsrN+XHakPvUkCmtynFuzAkxwzgpLrpRzZSZFhE7m+B1xMrMvhRWytSz2o/zaN5GwPpuM+VIoe6uO3OF1NU+N3bH+IIw= SpamDiagnosticOutput: 1:23 SpamDiagnosticMetadata: NSPM X-OriginatorOrg: caviumnetworks.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 03 Dec 2015 18:15:39.2783 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-Transport-CrossTenantHeadersStamped: CO2PR07MB618 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Dec 03, 2015 at 05:47:08PM +0000, Catalin Marinas wrote: > On Wed, Dec 02, 2015 at 12:29:04AM +0300, Yury Norov wrote: > > My question. Why aarch64 defines COMPAT_SHMLBA as 0x4000? > > This was done to match the arch/arm value of 4 * 4K. The historical > 32-bit reason for 4 pages is to cope with aliasing VIPT caches (see > https://git.kernel.org/cgit/linux/kernel/git/tglx/history.git/commit?id=4197692eef113eeb8e3e413cc70993a5e667e5b8) > > > If there's > > no specific reason for it, it looks like a bug, and we should > > define it like in arch/arm: > > #define SHMLBA (4 * PAGE_SIZE) /* attach addr a multiple of this */ > > I guess you meant COMPAT_SHMLBA. I citated arm code here. In aarch64 it's COMPAT_SHMLBA, of course. > I'm not sure there is much value in > keeping 4*PAGE_SIZE for larger page sizes but I agree that the current > 16K value doesn't work well with 64K pages. Arnd told there will be a workaround for arm v6 caches. Than this header will not be needed at all. Until that, this is simpliest fix as it doesn't affect userspace. > > -- > Catalin From mboxrd@z Thu Jan 1 00:00:00 1970 From: ynorov@caviumnetworks.com (Yury Norov) Date: Thu, 3 Dec 2015 21:14:41 +0300 Subject: [PATCH v6 14/19] arm64:ilp32: add sys_ilp32.c and a separate table (in entry.S) to use it In-Reply-To: <20151203174708.GO10747@e104818-lin.cambridge.arm.com> References: <1447795019-30176-1-git-send-email-ynorov@caviumnetworks.com> <1447795019-30176-15-git-send-email-ynorov@caviumnetworks.com> <3754277.KmO9Nk3XLD@wuerfel> <20151201212904.GA14442@yury-N73SV> <20151203174708.GO10747@e104818-lin.cambridge.arm.com> Message-ID: <20151203181441.GA16808@yury-N73SV> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Thu, Dec 03, 2015 at 05:47:08PM +0000, Catalin Marinas wrote: > On Wed, Dec 02, 2015 at 12:29:04AM +0300, Yury Norov wrote: > > My question. Why aarch64 defines COMPAT_SHMLBA as 0x4000? > > This was done to match the arch/arm value of 4 * 4K. The historical > 32-bit reason for 4 pages is to cope with aliasing VIPT caches (see > https://git.kernel.org/cgit/linux/kernel/git/tglx/history.git/commit?id=4197692eef113eeb8e3e413cc70993a5e667e5b8) > > > If there's > > no specific reason for it, it looks like a bug, and we should > > define it like in arch/arm: > > #define SHMLBA (4 * PAGE_SIZE) /* attach addr a multiple of this */ > > I guess you meant COMPAT_SHMLBA. I citated arm code here. In aarch64 it's COMPAT_SHMLBA, of course. > I'm not sure there is much value in > keeping 4*PAGE_SIZE for larger page sizes but I agree that the current > 16K value doesn't work well with 64K pages. Arnd told there will be a workaround for arm v6 caches. Than this header will not be needed at all. Until that, this is simpliest fix as it doesn't affect userspace. > > -- > Catalin