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=-8.3 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, PLING_QUERY,SPF_PASS,URIBL_BLOCKED,USER_IN_DEF_DKIM_WL 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 2AE50C6369F for ; Sat, 19 Jan 2019 16:37:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id F03B92086D for ; Sat, 19 Jan 2019 16:37:19 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="VRuCmDfa" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728387AbfASQhP (ORCPT ); Sat, 19 Jan 2019 11:37:15 -0500 Received: from mail-it1-f196.google.com ([209.85.166.196]:50714 "EHLO mail-it1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726686AbfASQhP (ORCPT ); Sat, 19 Jan 2019 11:37:15 -0500 Received: by mail-it1-f196.google.com with SMTP id z7so11101194iti.0 for ; Sat, 19 Jan 2019 08:37:14 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=RsBVz+eHEl/3ZPefaxE4HYS9c25LyOrrYZKkuUrq3LE=; b=VRuCmDfaTMCcAaTkuAtHy5L/f8oa8NpJPHL5o3imhRAlBU/wHTVews6u25pj5+DRma Z/aR9MElKxfMU+eqzR4w6Z0sBc87XwdgRb73ZmsADaDhRvcInbwymFDudkMOkrFYUNBw MW9gCpcu49SLI38nSgBSRqxIxQTW/D0NR/EE4s2LcmkzqMcFdHPMce+P0ho6BGPhbv3N 1FNbfrqVQteSE7+x/FWX3as18USJJLBktU7QywyLwEhZqJRow1SDlH9ekSBcXwFFfnRQ GuHYG25zvH7kwnP+79E24sNwkN2n/X3jPcCm7irPjT+Q1bpyiEyulyxQAyHYHXkHbDQe 2anQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=RsBVz+eHEl/3ZPefaxE4HYS9c25LyOrrYZKkuUrq3LE=; b=Rf6ccDAz/hX9+XnzvXe0amEbtg+N/smZv+EDa57TDgBT8l8EF3KicH2NvoRGDgOxMF hBqkl7Ttzoz0Tcg61YibNCoBr4JYf3JawfU/fCm+lsS2yHQoh32ZwJpb9V2rkOw8oCMA /o7752QdO4gGPPQqr5kW41wEq13oWEFqK9nVtKlKCbkVNEbSRo2S31jx2v1BVEVQ7q/U 6gTwT3lA97GNg8/sSBCgDu0CjMEwIJDYzuUrzI1AHSH9pKsuUdnw/IWiznEDvQa8sqc/ vchx59IsGrvPaKnkaMC3/qiqlknYCCS4qyxefADhOSykaiHLTR5vIFyrD3bCiSMhW0LY N0LQ== X-Gm-Message-State: AJcUukc1/SQcKzieaYBLCnxHeaSy+Yr/DHuHaAzR68EQRWHrNLqzQUOw QBIba80Kz2xnwMywqng3kLx7dMB254qQvx6eugxFuw== X-Google-Smtp-Source: ALg8bN64b2RbPgi/+znltsNBBN3v1OsSGh1G8JKR5Z26PsOU/iMHmUA8UiDBM9pkiFhdG8EcB3e++7/KPYY7IsfuPCE= X-Received: by 2002:a05:660c:f94:: with SMTP id x20mr11871667itl.144.1547915833854; Sat, 19 Jan 2019 08:37:13 -0800 (PST) MIME-Version: 1.0 References: In-Reply-To: From: Dmitry Vyukov Date: Sat, 19 Jan 2019 17:37:02 +0100 Message-ID: Subject: Re: [RESEND BUG REPORT] System hung! Due to ftrace or KASAN? To: Zenghui Yu , Dave Hansen , Andy Lutomirski , Peter Zijlstra , Thomas Gleixner , Ingo Molnar , Borislav Petkov , "H. Peter Anvin" , "the arch/x86 maintainers" Cc: Steven Rostedt , linux-trace-devel@vger.kernel.org, kasan-dev , "open list:KERNEL BUILD + fi..." , LKML Content-Type: text/plain; charset="UTF-8" Sender: linux-trace-devel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-trace-devel@vger.kernel.org On Fri, Jan 18, 2019 at 6:45 PM Zenghui Yu wrote: > > Hi, All! > > I compiled the latest kernel and installed it on my old laptop (Hardware name: > Hewlett-Packard HP ProBook 440 G2/2247, BIOS M74 Ver. 01.02 06/17/2014). But > when I tried to enable function tracer via debugfs, the system went _hung_! > Compared with the last kernel compiling process, the only change I have made > is that I enabled KASAN configuration this time. > > Reproducing this issue is simple as below: > > 0. `uname -a` shows: > Linux ubuntuu 5.0.0-rc2+ #9 SMP Fri Jan 18 03:04:01 CST 2019 > x86_64 x86_64 x86_64 GNU/Linux > > 1. `make menuconfig` to enable KASAN configuration: > Kernel hacking ---> Memory Debugging ---> > KASAN: runtime memory debugger > > compile, install, reboot, then `dmesg | grep kasan` shows: > [ 0.342882] kasan: KernelAddressSanitizer initialized > > 2. enable function tracer > `echo function > /sys/kernel/debug/tracing/current_tracer` > (then my poor laptop was locked and didn't respond to me ...) > > What's more, enabling function graph tracer will suffer from the same problem. > I have no idea about what wrong thing had happened inside kernel -- > about ftrace, > or about KASAN? So I report it to you and waiting for your solution! > > I have provided my *.config* file as attachment for those who're interested in > this issue. But sorry for that I can't provide any useful call trace > because the > system went down so quickly. > > P.S. I'm a newcomer for KASAN. If any mis-configuration or > mis-understand, please > fix me up and let me know :). Hi Zenghui, I've tried to reproduce this, but kernel crashes during boot with this config for me. I am commit 2339e91d0e6609e17943a0ab3c3c8c4044760c05, the config is basically yours but updated for newer compiler and with builtin modules: https://gist.githubusercontent.com/dvyukov/9af234617749aa4eada67ba8c2e4f46c/raw/d0e09ddf255962313a82bb552c3fc0d832fa6844/gistfile1.txt TITLE: WARNING in note_page MAINTAINERS: [dave.hansen@linux.intel.com luto@kernel.org peterz@infradead.org tglx@linutronix.de mingo@redhat.com bp@alien8.de hpa@zytor.com x86@kernel.org linux-kernel@vger.kernel.org] ------------[ cut here ]------------ x86/mm: Found insecure W+X mapping at address native_usergs_sysret64+0x0/0x10 WARNING: CPU: 3 PID: 1 at arch/x86/mm/dump_pagetables.c:263 note_wx arch/x86/mm/dump_pagetables.c:262 [inline] WARNING: CPU: 3 PID: 1 at arch/x86/mm/dump_pagetables.c:263 note_page+0x800/0xaf0 arch/x86/mm/dump_pagetables.c:302 Kernel panic - not syncing: panic_on_warn set ... CPU: 3 PID: 1 Comm: swapper/0 Not tainted 5.0.0-rc2+ #16 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x7b/0xb5 lib/dump_stack.c:113 panic+0x18e/0x351 kernel/panic.c:214 __warn+0x13c/0x140 kernel/panic.c:571 report_bug+0xd7/0x140 lib/bug.c:186 fixup_bug.part.11+0x2d/0x60 arch/x86/kernel/traps.c:178 fixup_bug arch/x86/include/asm/paravirt.h:776 [inline] do_error_trap+0xb6/0xc0 arch/x86/kernel/traps.c:271 do_invalid_op+0x3b/0x50 arch/x86/kernel/traps.c:290 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:973 RIP: 0010:note_wx arch/x86/mm/dump_pagetables.c:262 [inline] RIP: 0010:note_page+0x800/0xaf0 arch/x86/mm/dump_pagetables.c:302 Code: 4d 32 00 4c 89 7b 28 48 c7 43 30 00 00 00 00 e9 46 fc ff ff 4c 89 ee 48 c7 c7 a0 35 c5 ae c6 05 02 81 1e 02 01 e8 50 93 01 00 <0f> 0b 48 8b 7d 90 e8 75 4c 32 00 48 8b 43 20 48 89 45 c8 e9 72 f9 RSP: 0000:ffff88805d5c7d18 EFLAGS: 00010286 RAX: 0000000000000000 RBX: ffff88805d5c7e58 RCX: ffffffffae7f11db RDX: 0000000000000001 RSI: 0000000000000004 RDI: 0000000000000246 RBP: ffff88805d5c7da0 R08: ffffed100bab8f5c R09: ffffed100bab8f5c R10: 0000000000000002 R11: ffffed100bab8f5c R12: 0000000000000000 R13: ffffffffae800000 R14: 0000000000000004 R15: 0000000000000000 walk_pmd_level arch/x86/mm/dump_pagetables.c:428 [inline] walk_pud_level arch/x86/mm/dump_pagetables.c:459 [inline] walk_p4d_level arch/x86/mm/dump_pagetables.c:484 [inline] ptdump_walk_pgd_level_core+0x566/0x6e0 arch/x86/mm/dump_pagetables.c:552 ptdump_walk_user_pgd_level_checkwx+0x4e/0x50 arch/x86/mm/dump_pagetables.c:600 pti_finalize+0x27/0xaf arch/x86/mm/pti.c:682 kernel_init+0x3e/0x130 init/main.c:1066 ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:352 Kernel Offset: 0x2c800000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff) Rebooting in 86400 seconds..