Re: [Crash-utility] [PATCH v2] arm64: fix kernel memory map handling for kaslr-enabled kernel

vmcoreinfo_append_str("NUMBER(kimage_voffset)=%llx\n", kimage_voffset);

On 24/05/2016:01:59:06 PM, Dave Anderson wrote: > > > ----- Original Message ----- > > Yet some issues, but ... > > > > Hi Takahiro, > > Here are my general comments on my testing of the v2 patch, followed > by a few comments in the patch itself. > > First, the combination of the new memory map layout and KASLR is somewhat > confusing. I am testing your patch on a 4.6.0-0.rc7.git2.1.fc25 kernel > that has this configuration: > > config-arm64:# CONFIG_RANDOMIZE_BASE is not set > > So KASLR doesn't really enter into the picture. But when bringing > up the crash session, it shows the "kaslr kernel" WARNING: > > # ./crash > > crash 7.1.5++ > Copyright (C) 2002-2016 Red Hat, Inc. > Copyright (C) 2004, 2005, 2006, 2010 IBM Corporation > Copyright (C) 1999-2006 Hewlett-Packard Co > Copyright (C) 2005, 2006, 2011, 2012 Fujitsu Limited > Copyright (C) 2006, 2007 VA Linux Systems Japan K.K. > Copyright (C) 2005, 2011 NEC Corporation > Copyright (C) 1999, 2002, 2007 Silicon Graphics, Inc. > Copyright (C) 1999, 2000, 2001, 2002 Mission Critical Linux, Inc. > This program is free software, covered by the GNU General Public License, > and you are welcome to change it and/or distribute copies of it under > certain conditions. Enter "help copying" to see the conditions. > This program has absolutely no warranty. Enter "help warranty" for details. > > WARNING: kimage_voffset not identified for kaslr kernel > GNU gdb (GDB) 7.6 > Copyright (C) 2013 Free Software Foundation, Inc. > License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html> > This is free software: you are free to change and redistribute it. > There is NO WARRANTY, to the extent permitted by law. Type "show copying" > and "show warranty" for details. > This GDB was configured as "aarch64-unknown-linux-gnu"... > > KERNEL: /usr/lib/debug/lib/modules/4.6.0-0.rc7.git2.1.fc25.aarch64/vmlinux > DUMPFILE: /dev/crash > CPUS: 8 > DATE: Tue May 24 10:08:08 2016 > UPTIME: 11 days, 18:32:41 > LOAD AVERAGE: 0.17, 0.09, 0.12 > TASKS: 197 > NODENAME: apm-mustang-ev3-36.khw.lab.eng.bos.redhat.com > RELEASE: 4.6.0-0.rc7.git2.1.fc25.aarch64 > VERSION: #1 SMP Thu May 12 13:28:43 UTC 2016 > MACHINE: aarch64 (unknown Mhz) > MEMORY: 16 GB > PID: 7556 > COMMAND: "crash" > TASK: fffffe00beb45400 [THREAD_INFO: fffffe00beb98000] > CPU: 7 > STATE: TASK_RUNNING (ACTIVE) > > crash> Do not know whats missing, I am yet not able to reach "crash>" prompt. I have crash utility having this patch on top of "commit 8ceb1ac628bf6a0a7f0bbfff030ec93081bca4cd" [1]. I have kernel code v4.6+kexec-v15 [2]. In my .config: # CONFIG_KASAN is not set # CONFIG_RANDOMIZE_BASE is not set This is what I get: [root@dhcppc15 crash]# ./crash /lib/modules/4.6.0+/build/vmlinux /var/crash/127.0.0.1-2016-05-26-09\:40\:05/vmcore crash 7.1.5++ Copyright (C) 2002-2016 Red Hat, Inc. Copyright (C) 2004, 2005, 2006, 2010 IBM Corporation Copyright (C) 1999-2006 Hewlett-Packard Co Copyright (C) 2005, 2006, 2011, 2012 Fujitsu Limited Copyright (C) 2006, 2007 VA Linux Systems Japan K.K. Copyright (C) 2005, 2011 NEC Corporation Copyright (C) 1999, 2002, 2007 Silicon Graphics, Inc. Copyright (C) 1999, 2000, 2001, 2002 Mission Critical Linux, Inc. This program is free software, covered by the GNU General Public License, and you are welcome to change it and/or distribute copies of it under certain conditions. Enter "help copying" to see the conditions. This program has absolutely no warranty. Enter "help warranty" for details. GNU gdb (GDB) 7.6 Copyright (C) 2013 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html> This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. Type "show copying" and "show warranty" for details. This GDB was configured as "aarch64-unknown-linux-gnu"... crash: read error: kernel virtual address: fffffc0008b80fd8 type: "possible" WARNING: cannot read cpu_possible_map crash: read error: kernel virtual address: fffffc0008b80dd8 type: "present" WARNING: cannot read cpu_present_map crash: read error: kernel virtual address: fffffc0008b80bd8 type: "online" WARNING: cannot read cpu_online_map crash: read error: kernel virtual address: fffffc0008b811d8 type: "active" WARNING: cannot read cpu_active_map crash: read error: kernel virtual address: fffffc00091f6c78 type: "shadow_timekeeper xtime_sec" crash: read error: kernel virtual address: fffffc0008b9223c type: "init_uts_ns" crash: /lib/modules/4.6.0+/build/vmlinux and /var/crash/127.0.0.1-2016-05-26-09:40:05/vmcore do not match! Usage: crash [OPTION]... NAMELIST MEMORY-IMAGE[@ADDRESS] (dumpfile form) crash [OPTION]... [NAMELIST] (live system form) Enter "crash -h" for details. ~Pratyush [1] https://github.com/pratyushanand/crash/commits/master [2] https://github.com/pratyushanand/linux/commits/upstream_arm64_devel_test