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=-2.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no 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 8E88CC74A21 for ; Wed, 10 Jul 2019 13:27:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5B2EC2064B for ; Wed, 10 Jul 2019 13:27:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1562765250; bh=DYFIWwQJQxK/aOVUf88sxLGFW7Cu4ptjJEnA2QgLruQ=; h=Date:From:To:cc:Subject:In-Reply-To:References:List-ID:From; b=gyLJfTnjSAOqsOPBgAZemnjzfww8lKlHUrRWe9+lQxos0YxlTuLn2yusR5lcDu3NI WWG+Wx2jSz1YciSCNjFSoT5HjhItPIRzYTpmDojzVDm74ldcPYJ9xvoOn7niwEQcF+ t0G5loqoN7ohWX8YjYsTAK7573jBOO/fZ3aGU9zo= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727363AbfGJN13 (ORCPT ); Wed, 10 Jul 2019 09:27:29 -0400 Received: from mail.kernel.org ([198.145.29.99]:47606 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725994AbfGJN13 (ORCPT ); Wed, 10 Jul 2019 09:27:29 -0400 Received: from pobox.suse.cz (prg-ext-pat.suse.com [213.151.95.130]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id B26F620861; Wed, 10 Jul 2019 13:27:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1562765247; bh=DYFIWwQJQxK/aOVUf88sxLGFW7Cu4ptjJEnA2QgLruQ=; h=Date:From:To:cc:Subject:In-Reply-To:References:From; b=cc+jznRp8oLOBE7fHjwCUfW4DYkKh/sKMOSScXyBLT2mxx456dv5XKtJotUq9+3hG HHTZhkgWp7g/SVdptOvkndTADQH4t4Uk0xYb4WXIU4mEmZoP2UnZ3023jcIF2HOE3K O7P3cVRDLj5IUn/UbSm0LR29k7ftdV9MWu/Ps6/Y= Date: Wed, 10 Jul 2019 15:27:18 +0200 (CEST) From: Jiri Kosina To: Peter Zijlstra cc: Thomas Gleixner , Xi Ruoyao , Kees Cook , Linus Torvalds , Ingo Molnar , Linux List Kernel Mailing , Borislav Petkov , Len Brown , Andrew Morton , "Rafael J. Wysocki" , Tony Luck , Bob Moore , Erik Schmauss , Josh Poimboeuf , Daniel Bristot de Oliveira , Nadav Amit Subject: Re: [GIT PULL] x86/topology changes for v5.3 In-Reply-To: <20190710132144.GM3402@hirez.programming.kicks-ass.net> Message-ID: References: <201907091727.91CC6C72D8@keescook> <1ad2de95e694a29909801d022fe2d556df9a4bd5.camel@mengyan1223.wang> <20190710132144.GM3402@hirez.programming.kicks-ass.net> User-Agent: Alpine 2.21 (LSU 202 2017-01-01) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 10 Jul 2019, Peter Zijlstra wrote: > > > BUG: unable to handle page fault for address: ffffffff9edc1598 > > > #PF: supervisor write access in kernel mode > > > #PF: error_code(0x0003) - permissions violation > > > PGD 1a20c067 P4D 1a20c067 PUD 1a20d063 PMD 8000000019e000e1 > > > Oops: 0003 [#1] SMP PTI > > > 2 PID: 151 Comm: systemd-udevd Not tainted 5.2.0+ #54 > > > Hardware name: LENOVO 20175/INVALID, BIOS 66CN54WW 01/21/2013 > > > RIP: 0010:static_key_set_mod.isra.0+0x10/0x30 > > > Code: 48 8b 37 83 e6 03 48 09 c6 48 89 37 c3 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f0 a8 03 75 0d 48 8b 37 83 e6 03 48 09 c6 <48> 89 37 c3 0f 0b 48 8b 37 83 e6 03 48 09 c6 48 89 37 c3 66 66 2e > > > RSP: 0000:ffffa606c032bc98 EFLAGS: 00010286 > > > RAX: ffff9981ddce30a0 RBX: ffffffff9edc1590 RCX: 0000000000000000 > > > RDX: 0000000000000020 RSI: ffff9981ddce30a0 RDI: ffffffff9edc1598 > > > RBP: ffffffffc06f4000 R08: ffff9981e6003980 R09: ffff9981ddce30a0 > > > R10: 0000000000000000 R11: 0000000000028b56 R12: ffffffffc06f8880 > > > R13: ffff9981ddce3080 R14: ffffffffc06f4008 R15: ffffffffc06f6dc0 > > > FS: 00007f992dd9a680(0000) GS:ffff9981e7080000(0000) knlGS:0000000000000000 > > > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > > > CR2: ffffffff9edc1598 CR3: 00000002233aa001 CR4: 00000000001606e0 > > > Call Trace: > > > jump_label_module_notify+0x1e7/0x2b0 > > > notifier_call_chain+0x44/0x70 > > > blocking_notifier_call_chain+0x43/0x60 > > > load_module+0x1bcb/0x2490 > > > ? vfs_read+0x11f/0x150 > > > ? __do_sys_finit_module+0xbf/0xe0 > > > __do_sys_finit_module+0xbf/0xe0 > > > do_syscall_64+0x43/0x110 > > > entry_SYSCALL_64_after_hwframe+0x44/0xa9 > > > > > > Josh, didn't you mention that yesterday or so? > > > > That's what Tony yesterday indicated on IRC that his system is suffering > > from as well. > > > > Adding Daniel to check whether this couldn't be some fallout of jumplabel > > batching. > > AFAICT this is _before_ we get to patching. The function that explodes > is static_key_set_mod(), as called from jump_label_add_module(). > > What that function does is for all patch sites in the module, find the > corresponding key; if that key is not also in that module, allocate a > static_key_mod structure and link the module entries to the key. Such > that we can find all instances from a given key. > > I don't think anything here has changed in a while. Hm, and it seems to explode on dereferencing the static_key* in %rsi 21: 48 8b 37 mov (%rdi),%rsi 24: 83 e6 03 and $0x3,%esi 27: 48 09 c6 or %rax,%rsi 2a:* 48 89 37 mov %rsi,(%rdi) <-- trapping instruction which looks odd, as it derefenced it successfully just 3 instructions ago. -- Jiri Kosina SUSE Labs