Hi,all
Here's some explanation for this patch
Without patch:
Consider the following scenario
->arm64_init(PRE_GDB)
case PRE_GDB:
...
292 } else if (ms->VA_BITS_ACTUAL) {
293 ms->modules_vaddr =
(st->_stext_vmlinux & TEXT_OFFSET_MASK) -
ARM64_MODULES_VSIZE;-->//ms->modules_vaddr=0xfffffffff8000000
294 ms->modules_end =
ms->modules_vaddr + ARM64_MODULES_VSIZE
-1;--->//ms->modules_end=0xffffffffffffffff
295 ms->vmalloc_start_addr =
ms->modules_end + 1;--->//ms->vmalloc_start_addr=0
296 } else {
....
}
arm64_calc_kimage_voffset();
.....
Since arm64_calc_kimage_voffset() depends on vmalloc_start_addr,
kimage_voffset cannot be calculated correctly.
st->_stext_vmlinux can be initialized in numeric_forward(),just set
st->_stext_vmlinux to UNINITIALIZED.
============
log as below:
$ ~/crash/crash/crash vmlinux DDRCS0.bin@0x80000000 --machdep vabits_actual=48
crash 8.0.1++
Copyright (C) 2002-2022 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, 2020-2022 NEC Corporation
Copyright (C) 1999, 2002, 2007 Silicon Graphics, Inc.
Copyright (C) 1999, 2000, 2001, 2002 Mission Critical Linux, Inc.
Copyright (C) 2015, 2021 VMware, 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.
NOTE: setting vabits_actual to: 48
WARNING: kimage_voffset cannot be determined from the dumpfile.
Try using the command line option: --machdep kimage_voffset=<addr>
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--target=aarch64-elf-linux".
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crash: read error: kernel virtual address: ffff80001083d4a0 type:
"kernel_config_data"
WARNING: cannot read kernel_config_data
crash: read error: kernel virtual address: ffff80001170e798 type: "possible"
WARNING: cannot read cpu_possible_map
crash: read error: kernel virtual address: ffff80001170e7a8 type: "present"
WARNING: cannot read cpu_present_map
crash: read error: kernel virtual address: ffff80001170e788 type: "online"
WARNING: cannot read cpu_online_map
crash: read error: kernel virtual address: ffff80001170e7c0 type: "active"
WARNING: cannot read cpu_active_map
crash: read error: kernel virtual address: ffff8000122e00f0 type:
"shadow_timekeeper xtime_sec"
crash: read error: kernel virtual address: ffff80001171dc04 type: "init_uts_ns"
crash: vmlinux and /var/tmp/ramdump_elf_m2ivkg do not match!
Usage:
crash [OPTION]... NAMELIST MEMORY-IMAGE[@ADDRESS] (dumpfile form)
crash [OPTION]... [NAMELIST] (live system form)
Enter "crash -h" for details.
Qianli Zhao <zhaoqianligood@xxxxxxxxx> 于2022年6月24日周五 00:14写道：
>
> From: Qianli Zhao <qianli.zhao@xxxxxxxxxx>
>
> Setting st->_stext_vmlinux to UNINITIALIZED to search for "_stext" from the vmlinux
> Without the patch, if we do not enable kaslr, will get the wrong
> MODULES/VMALLOC ranges, cause parsing dump failure
>
> Signed-off-by: Qianli Zhao <qianli.zhao@xxxxxxxxxx>
> ---
> arm64.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/arm64.c b/arm64.c
> index 0f615cf..4458a66 100644
> --- a/arm64.c
> +++ b/arm64.c
> @@ -149,6 +149,9 @@ arm64_init(int when)
>
> ms = machdep->machspec;
>
> + if (ms->VA_BITS_ACTUAL)
> + st->_stext_vmlinux = UNINITIALIZED;
> +
> if (!ms->kimage_voffset && STREQ(pc->live_memsrc, "/dev/crash"))
> ioctl(pc->mfd, DEV_CRASH_ARCH_DATA, &ms->kimage_voffset);
>
> --
> 2.17.1
>
--
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