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=-10.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 EA377C433C1 for ; Sun, 21 Mar 2021 08:35:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AF2CE61931 for ; Sun, 21 Mar 2021 08:35:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229894AbhCUHrb (ORCPT ); Sun, 21 Mar 2021 03:47:31 -0400 Received: from mout.gmx.net ([212.227.17.21]:35115 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229784AbhCUHr2 (ORCPT ); Sun, 21 Mar 2021 03:47:28 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gmx.net; s=badeba3b8450; t=1616312818; bh=SuG/TA7sCK4l9pQ8LvndcMV7fjeqGSpXtyAJ9CMDF7c=; h=X-UI-Sender-Class:Subject:From:To:Cc:Date:In-Reply-To:References; b=ijIdDW684lpym5a2OHjhc3OlaF78IlxT20Ix+Wk74scJM8Xl2A76bH8lW8cd3uDz5 E9ndUmNjLGGAhtMO8IjP0ntWPEySeAmXueNvVPUCqg1tCceSHMRYrnjzqNzXXdktRW BCbF2ydeluR3X2WomTHLByNpmGCavYjn3vc9m5co= X-UI-Sender-Class: 01bb95c1-4bf8-414a-932a-4f6e2808ef9c Received: from homer.fritz.box ([185.221.151.199]) by mail.gmx.net (mrgmx105 [212.227.17.168]) with ESMTPSA (Nemesis) id 1Mt757-1lhjw3076v-00tVKq; Sun, 21 Mar 2021 08:46:58 +0100 Message-ID: Subject: Re: [ANNOUNCE] v5.12-rc3-rt3 From: Mike Galbraith To: Sebastian Andrzej Siewior , Thomas Gleixner Cc: LKML , linux-rt-users , Steven Rostedt Date: Sun, 21 Mar 2021 08:46:56 +0100 In-Reply-To: <1f63f1fcea10fc179881384cd838b1c9e5207b82.camel@gmx.de> References: <20210319223357.uknv2t5uvxvzb46x@linutronix.de> <1f63f1fcea10fc179881384cd838b1c9e5207b82.camel@gmx.de> Content-Type: text/plain; charset="ISO-8859-15" User-Agent: Evolution 3.34.4 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Provags-ID: V03:K1:5WpsyfvFngwZ4W11hzRr4dl+GGSxMLC9KVKOmzLjq9jB68TrDDg TwRzucfzOCRwjb3DCDU7XL0Xkz6HBesfz4VKu7l3wjotqKkYH4E/TNPmwUv5GJT7K+iZ5G/ tD9G02hMQuwuoDl3fxtNVYrLVl3yasDWVDSzM/lDFnxsrkfcydkOMlWuLbLWRTt4H7yV70T 2su/poxBiQ1MS15Nd/GrQ== X-UI-Out-Filterresults: notjunk:1;V03:K0:j2ayHTvOodI=:wxmEyrNzqEay9q3FQO+xxX NVefhFnx0ZwUNix1MIFxtEt4TRSbhkmqeFnSvH4GXtBjfG0zK+sWJJz6ozvk0lwoS6CvCQYE3 jN7Qrzt9fct1Ao0Ehi/gC9m382Al90I4Jqafx1lOLZX98OPGO2CdWCean5uoZhTFDMyg6oKi7 MtByerOg1lKa1WVeW9Cua1UWAht+pUc+EhM8jj84yKSWVIkKsTlU80qNUdHiXtti3QBGgoVbN zT+krvnU4e2Jzeu19sf8LHVpO21LZDkwKfRmPjX81I3fH3YkNA8kqhDV9Cu2VKRtB8AaxVs+X NPE19jXPCgoAtPfr4KFZ7z0cYKGCkBJSZIDIdW1OpaWzS07IQHSR4Yfz6bcDtvwrTHXAE+DIs rlNBk4IGaSkZzv36VdkhljCTHZoQTdTktl2pzIKqD3Oxl3hJVU6BpKuvNSOR5udo9kMDBhyXL 5N1AoEcWTaFh+5aziAAmFbFpILYVJc7ZvOJlp2+SWjqawL5LsgrlO7R4IsI7w+PWkG9DoOsgw +eI/xWs/268ytlLIKh3DLPuRTrRRpyNhC7OiGzYgiKV0g6Gyx7KIIoy2ikHP/ENGJM0/N5kEZ G/CN0URHzuaFlSp1Nhec2rMjgVXLBuhDQtDpL8V428byY/HnjqqNHCoURMv1ZEtJCRjNUEume U1C7zin1b/bLsmjM3DM82jsWFr64D8MeC+nyNXUImYmnQZ9XHa/3CrW+dOrx7wnGta+JEcUtA Sz8Bu/J5myXI83iulMgrLFt3uP6ZnlwfE2nABVTMV7FbPukTJofocvcOCeIP2kOF+bf/l+E1E gxCp6byEr8PHb8Zu0G3lyBfvQ2qdEdxhzhb2eOIyfxtwyyRfEZJbC39Zyj88rSr7vugJYKnb6 V7rvGpZ8JbUBL/YkU4EA== Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, 2021-03-20 at 09:18 +0100, Mike Galbraith wrote: > On Fri, 2021-03-19 at 23:33 +0100, Sebastian Andrzej Siewior wrote: > > Dear RT folks! > > > > I'm pleased to announce the v5.12-rc3-rt3 patch set. > > My little rpi4b is fairly unhappy with 5.12-rt, whereas 5.11-rt works > fine on it. The below spew is endless, making boot endless. I turned > it into a WARN_ON_ONCE to see if the thing would finish boot, and > surprisingly, it seems perfectly fine with that bad idea. Having not > the foggiest clue what I'm doing down in arm arch-land, bug is in no > immediate danger :) Actually, it looks like a defenseless little buglet, and this gripe simply wants to be disabled for RT. arm64: disable arch_faults_on_old_pte() preemptible() warning for RT arch_faults_on_old_pte() was never called in < 5.12-rt, but 5.12 added arch_wants_old_prefaulted_pte(), which is a wrapper thereof, and thus finish_fault() -> do_set_pte() -> arch_wants_old_prefaulted_pte() now calls it, in preemptible context, and a flood of complaints ensues. Kill it for RT. Signed-off-by: Mike Galbraith =2D-- arch/arm64/include/asm/pgtable.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) =2D-- a/arch/arm64/include/asm/pgtable.h +++ b/arch/arm64/include/asm/pgtable.h @@ -979,7 +979,7 @@ static inline void update_mmu_cache(stru */ static inline bool arch_faults_on_old_pte(void) { - WARN_ON(preemptible()); + WARN_ON(!IS_ENABLED(CONFIG_PREEMPT_RT) && preemptible()); return !cpu_has_hw_af(); } > > [ 2.216913] WARNING: CPU: 0 PID: 1 at arch/arm64/include/asm/pgtable.= h:982 do_set_pte+0x1cc/0x1d4 > [ 2.216949] Modules linked in: > [ 2.216961] CPU: 0 PID: 1 Comm: init Not tainted 5.12.0.g425ed5a-v8-r= t #33 > [ 2.216973] Hardware name: Raspberry Pi 4 Model B Rev 1.4 (DT) > [ 2.216979] pstate: 20000005 (nzCv daif -PAN -UAO -TCO BTYPE=3D--) > [ 2.216990] pc : do_set_pte+0x1cc/0x1d4 > [ 2.217004] lr : filemap_map_pages+0x178/0x380 > [ 2.217016] sp : ffffffc01153bbb0 > [ 2.217020] x29: ffffffc01153bbb0 x28: fffffffe07d93080 > [ 2.217033] x27: 0000000000000000 x26: ffffff8101c9e000 > [ 2.217044] x25: ffffff8101b40fd8 x24: 0000000000000000 > [ 2.217054] x23: ffffff8101674170 x22: 0000007fb1b4b000 > [ 2.217064] x21: fffffffe07d93080 x20: ffffffc01153bcf0 > [ 2.217073] x19: 00200001f64c2fc3 x18: 0000000000000000 > [ 2.217082] x17: 0000000000000000 x16: 0000000000000000 > [ 2.217091] x15: 0000000000000000 x14: 0000000000000000 > [ 2.217100] x13: 0000000000000000 x12: 0000000000000000 > [ 2.217108] x11: 0000000000000000 x10: 0000000000000000 > [ 2.217117] x9 : ffffffc010209068 x8 : 000000000000000f > [ 2.217126] x7 : ffffff8101e87c68 x6 : fffffffe00000000 > [ 2.217135] x5 : 0000000000101e8b x4 : ffffff8101e880a8 > [ 2.217144] x3 : 0020000000000fc3 x2 : 0000000000000000 > [ 2.217153] x1 : 0000000000000000 x0 : 0000000000000000 > [ 2.217162] Call trace: > [ 2.217166] do_set_pte+0x1cc/0x1d4 > [ 2.217181] filemap_map_pages+0x178/0x380 > [ 2.217189] __handle_mm_fault+0x75c/0x930 > [ 2.217202] handle_mm_fault+0x178/0x25c > [ 2.217214] do_page_fault+0x16c/0x470 > [ 2.217233] do_translation_fault+0xbc/0xd8 > [ 2.217244] do_mem_abort+0x4c/0xbc > [ 2.217259] el0_ia+0x68/0xcc > [ 2.217272] el0_sync_handler+0x180/0x1b0 > [ 2.217284] el0_sync+0x170/0x180