From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-17.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7A814C07E98 for ; Mon, 5 Jul 2021 07:24:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 62A1F613D1 for ; Mon, 5 Jul 2021 07:24:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230011AbhGEH0g (ORCPT ); Mon, 5 Jul 2021 03:26:36 -0400 Received: from mail.kernel.org ([198.145.29.99]:59884 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229817AbhGEH0g (ORCPT ); Mon, 5 Jul 2021 03:26:36 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 4B629613CB; Mon, 5 Jul 2021 07:23:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1625469839; bh=7ruKeasU5fOpWnr71pr/Ny2Pl3C4Lo8Nw8CkUVL+Mn8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=QH5elm0xYGqW6xDbji9vo7lo9gAVrcpsek3gDbTnjn2JyjeV+eeUxaHZpIYWW8yy7 J46TjkLfJYUO7/wTvtXTuAR5BCh/aRPBHdbaKMSZYMRGdZp/sWUxts29ockCB1Zo7H YJC0LyQKWpupcxUYvJ3soAXIi9bb6tt+xyGwG67GB5kaF0/vBaWrHR4NROsQtox89A B4g2XH2VFTe/a+OvUA73KsyUAxarHCegQ0FYwjOiQ3AfZYi8Cl7ViO8M+BxKDMNa+v 3LIk0qR+xW7znu+jFlIXLrY+jH8wBWTQY7NH6coT5axhvspN60Cvj32Jq4z8QTU7ER mx1lJhDE9fgXQ== Date: Mon, 5 Jul 2021 10:23:52 +0300 From: Mike Rapoport To: Guenter Roeck Cc: linux-arm-kernel@lists.infradead.org, Andrew Morton , Kefeng Wang , Mike Rapoport , Russell King , Tony Lindgren , linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH v3 4/4] arm: extend pfn_valid to take into account freed memory map alignment Message-ID: References: <20210630071211.21011-1-rppt@kernel.org> <20210630071211.21011-5-rppt@kernel.org> <20210705042236.GA1463419@roeck-us.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210705042236.GA1463419@roeck-us.net> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Guenter, On Sun, Jul 04, 2021 at 09:22:36PM -0700, Guenter Roeck wrote: > On Wed, Jun 30, 2021 at 10:12:11AM +0300, Mike Rapoport wrote: > > From: Mike Rapoport > > > > When unused memory map is freed the preserved part of the memory map is > > extended to match pageblock boundaries because lots of core mm > > functionality relies on homogeneity of the memory map within pageblock > > boundaries. > > > > Since pfn_valid() is used to check whether there is a valid memory map > > entry for a PFN, make it return true also for PFNs that have memory map > > entries even if there is no actual memory populated there. > > > > Signed-off-by: Mike Rapoport > > Tested-by: Kefeng Wang > > With this patch in place, the romulus-bmc emulation in qemu gets the > following traceback: > > [ 2.863406] WARNING: CPU: 0 PID: 1 at arch/arm/mm/ioremap.c:287 __arm_ioremap_pfn_caller+0xf0/0x1dc ... > [ 2.876683] ---[ end trace b2f74b8536829970 ]--- > [ 2.876911] fsi-master-acf gpio-fsi: ioremap failed for resource [mem 0x9ef00000-0x9effffff] > [ 2.877492] fsi-master-acf gpio-fsi: Error -12 mapping coldfire memory > [ 2.877689] fsi-master-acf: probe of gpio-fsi failed with error -12 > > Reverting it fixes the problem. Also, the ioremap failure is no longer seen > after reverting this patch. I believe this should fix it: >From e2213b7e804daf0d31d47502379916f0542398bb Mon Sep 17 00:00:00 2001 From: Mike Rapoport Date: Mon, 5 Jul 2021 08:43:10 +0300 Subject: [PATCH] arm: ioremap: don't abuse pfn_valid() to check if pfn is in RAM The semantics of pfn_valid() is to check presence of the memory map for a PFN and not whether a PFN is in RAM. The memory map may be present for a hole in the physical memory and if such hole corresponds to an MMIO range, __arm_ioremap_pfn_caller() will produce a WARN() and fail: [ 2.863406] WARNING: CPU: 0 PID: 1 at arch/arm/mm/ioremap.c:287 __arm_ioremap_pfn_caller+0xf0/0x1dc [ 2.864812] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.13.0-09882-ga180bd1d7e16 #1 [ 2.865263] Hardware name: Generic DT based system [ 2.865711] Backtrace: [ 2.866063] [<80b07e58>] (dump_backtrace) from [<80b080ac>] (show_stack+0x20/0x24) [ 2.866633] r7:00000009 r6:0000011f r5:60000153 r4:80ddd1c0 [ 2.866922] [<80b0808c>] (show_stack) from [<80b18df0>] (dump_stack_lvl+0x58/0x74) [ 2.867117] [<80b18d98>] (dump_stack_lvl) from [<80b18e20>] (dump_stack+0x14/0x1c) [ 2.867309] r5:80118cac r4:80dc6774 [ 2.867404] [<80b18e0c>] (dump_stack) from [<80122fcc>] (__warn+0xe4/0x150) [ 2.867583] [<80122ee8>] (__warn) from [<80b08850>] (warn_slowpath_fmt+0x88/0xc0) [ 2.867774] r7:0000011f r6:80dc6774 r5:00000000 r4:814c4000 [ 2.867917] [<80b087cc>] (warn_slowpath_fmt) from [<80118cac>] (__arm_ioremap_pfn_caller+0xf0/0x1dc) [ 2.868158] r9:00000001 r8:9ef00000 r7:80e8b0d4 r6:0009ef00 r5:00000000 r4:00100000 [ 2.868346] [<80118bbc>] (__arm_ioremap_pfn_caller) from [<80118df8>] (__arm_ioremap_caller+0x60/0x68) [ 2.868581] r9:9ef00000 r8:821b6dc0 r7:00100000 r6:00000000 r5:815d1010 r4:80118d98 [ 2.868761] [<80118d98>] (__arm_ioremap_caller) from [<80118fcc>] (ioremap+0x28/0x30) [ 2.868958] [<80118fa4>] (ioremap) from [<8062871c>] (__devm_ioremap_resource+0x154/0x1c8) [ 2.869169] r5:815d1010 r4:814c5d2c [ 2.869263] [<806285c8>] (__devm_ioremap_resource) from [<8062899c>] (devm_ioremap_resource+0x14/0x18) [ 2.869495] r9:9e9f57a0 r8:814c4000 r7:815d1000 r6:815d1010 r5:8177c078 r4:815cf400 [ 2.869676] [<80628988>] (devm_ioremap_resource) from [<8091c6e4>] (fsi_master_acf_probe+0x1a8/0x5d8) [ 2.869909] [<8091c53c>] (fsi_master_acf_probe) from [<80723dbc>] (platform_probe+0x68/0xc8) [ 2.870124] r9:80e9dadc r8:00000000 r7:815d1010 r6:810c1000 r5:815d1010 r4:00000000 [ 2.870306] [<80723d54>] (platform_probe) from [<80721208>] (really_probe+0x1cc/0x470) [ 2.870512] r7:815d1010 r6:810c1000 r5:00000000 r4:815d1010 [ 2.870651] [<8072103c>] (really_probe) from [<807215cc>] (__driver_probe_device+0x120/0x1fc) [ 2.870872] r7:815d1010 r6:810c1000 r5:810c1000 r4:815d1010 [ 2.871013] [<807214ac>] (__driver_probe_device) from [<807216e8>] (driver_probe_device+0x40/0xd8) [ 2.871244] r9:80e9dadc r8:00000000 r7:815d1010 r6:810c1000 r5:812feaa0 r4:812fe994 [ 2.871428] [<807216a8>] (driver_probe_device) from [<80721a58>] (__driver_attach+0xa8/0x1d4) [ 2.871647] r9:80e9dadc r8:00000000 r7:00000000 r6:810c1000 r5:815d1054 r4:815d1010 [ 2.871830] [<807219b0>] (__driver_attach) from [<8071ee8c>] (bus_for_each_dev+0x88/0xc8) [ 2.872040] r7:00000000 r6:814c4000 r5:807219b0 r4:810c1000 [ 2.872194] [<8071ee04>] (bus_for_each_dev) from [<80722208>] (driver_attach+0x28/0x30) [ 2.872418] r7:810a2aa0 r6:00000000 r5:821b6000 r4:810c1000 [ 2.872570] [<807221e0>] (driver_attach) from [<8071f80c>] (bus_add_driver+0x114/0x200) [ 2.872788] [<8071f6f8>] (bus_add_driver) from [<80722ec4>] (driver_register+0x98/0x128) [ 2.873011] r7:81011d0c r6:814c4000 r5:00000000 r4:810c1000 [ 2.873167] [<80722e2c>] (driver_register) from [<80725240>] (__platform_driver_register+0x2c/0x34) [ 2.873408] r5:814dcb80 r4:80f2a764 [ 2.873513] [<80725214>] (__platform_driver_register) from [<80f2a784>] (fsi_master_acf_init+0x20/0x28) [ 2.873766] [<80f2a764>] (fsi_master_acf_init) from [<80f014a8>] (do_one_initcall+0x108/0x290) [ 2.874007] [<80f013a0>] (do_one_initcall) from [<80f01840>] (kernel_init_freeable+0x1ac/0x230) [ 2.874248] r9:80e9dadc r8:80f3987c r7:80f3985c r6:00000007 r5:814dcb80 r4:80f627a4 [ 2.874456] [<80f01694>] (kernel_init_freeable) from [<80b19f44>] (kernel_init+0x20/0x138) [ 2.874691] r10:00000000 r9:00000000 r8:00000000 r7:00000000 r6:00000000 r5:80b19f24 [ 2.874894] r4:00000000 [ 2.874977] [<80b19f24>] (kernel_init) from [<80100170>] (ret_from_fork+0x14/0x24) [ 2.875231] Exception stack(0x814c5fb0 to 0x814c5ff8) [ 2.875535] 5fa0: 00000000 00000000 00000000 00000000 [ 2.875849] 5fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 [ 2.876133] 5fe0: 00000000 00000000 00000000 00000000 00000013 00000000 [ 2.876363] r5:80b19f24 r4:00000000 [ 2.876683] ---[ end trace b2f74b8536829970 ]--- [ 2.876911] fsi-master-acf gpio-fsi: ioremap failed for resource [mem 0x9ef00000-0x9effffff] [ 2.877492] fsi-master-acf gpio-fsi: Error -12 mapping coldfire memory [ 2.877689] fsi-master-acf: probe of gpio-fsi failed with error -12 Use memblock_is_map_memory() instead of pfn_valid() to check if a PFN is in RAM or not. Reported-by: Guenter Roeck Signed-off-by: Mike Rapoport --- arch/arm/mm/ioremap.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/arch/arm/mm/ioremap.c b/arch/arm/mm/ioremap.c index 000e8210000b..80fb5a4a5c05 100644 --- a/arch/arm/mm/ioremap.c +++ b/arch/arm/mm/ioremap.c @@ -27,6 +27,7 @@ #include #include #include +#include #include #include @@ -284,7 +285,8 @@ static void __iomem * __arm_ioremap_pfn_caller(unsigned long pfn, * Don't allow RAM to be mapped with mismatched attributes - this * causes problems with ARMv6+ */ - if (WARN_ON(pfn_valid(pfn) && mtype != MT_MEMORY_RW)) + if (WARN_ON(memblock_is_map_memory(PFN_PHYS(pfn)) && + mtype != MT_MEMORY_RW)) return NULL; area = get_vm_area_caller(size, VM_IOREMAP, caller); -- 2.28.0 -- Sincerely yours, Mike.