[Crash-utility] Re: crash: seek error: kernel virtual address: ffffffff8292c360 type: "page_offset_base"

Hi Tao, Thanks for your reply, 1) Try to drop the "-S" of crash cmdline to see if it works. I have tried without -S, it was broken by another issue, the crash reported an error : _note_9: st_name: 1692 st_value: ffffffffc04d747c st_shndx: 22 st_info: ? __this_module: st_name: 1700 st_value: ffffffffc04d8380 st_shndx: 29 st_info: ? cleanup_module: st_name: 1714 st_value: ffffffffc04d6c48 st_shndx: 7 st_info: T FREEBUF(1) FREEBUF(0) <readmem: ffffffffab2df068, KVADDR, "nr_threads", 4, (FOE), 55f06caa495c> <read_proc_kcore: addr: ffffffffab2df068 paddr: 11cedf068 cnt: 4> crash: per_cpu_symbol_search(per_cpu__runqueues): NULL crash: cannot determine idle task addresses from init_tasks[] or runqueues[] crash: cannot resolve "init_task_union" 2) If not, then please try to disable the kernel kaslr at bootup by appending "nokaslr" to kernel cmdline, and invoke crash as your original way. After append the "nokaslr" to kernel command line, the crash without -S still report "crash: cannot resolve "init_task_union" But with "-S" parameter, crash can enter the CLI as normal. So, regarding the behavior, when without -S, the crash report "crash: cannot resolve "init_task_union"", this should not related to kaslr, right? If so, is that means missing kernel configuration/patch or gdb needs a special version? The current kernel is 6.1 stable, gdb version is 10.2.

Thanks, Br, Xiangyu 在 2024年12月12日 星期四 上午07:46:05 [GMT+8]， Tao Liu&lt;ltao(a)redhat.com&gt; 寫道： Hi xiangyu, On Fri, Dec 6, 2024 at 9:25 PM <xiangyu.chen(a)aol.com&gt; wrote: > > Hi Crash-utility folks, > > Recently, I am using crash to debug a live system. > When I execute the crash, it cannot enter the crash cmd shell, it was broken by crash seek error. > My kernel turned on the CONFIG_RANDOMIZE_BASE, and I added the kaslr=auto parameter to crash. > If I disable the CONFIG_RANDOMIZE_BASE, the issue has gone. > Could you please help to check if any config/parameter I was missing? Thanks. > > The following is my system information: > crash version: 8.0.6 > kernel version: 6.1.118 > Host system: qemux86-64 > > Here is the full log with -d: > root@intel-x86-64:/boot# crash -S /boot/vmlinux-6.1.118-yocto-standard /proc/kcore -d10 --kaslr=auto > 1) Try to drop the "-S" of crash cmdline to see if it works. 2) If not, then please try to disable the kernel kaslr at bootup by appending "nokaslr" to kernel cmdline, and invoke crash as your original way. Hope this helps. Thanks, Tao Liu > crash 8.0.6 > Copyright (C) 2002-2025 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, 2020-2024 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. > > get_live_memory_source: /proc/kcore > proc_kcore_data: > flags: 500 (KCORE_LOCAL|KCORE_ELF64) > segments: 10 > elf_header: 56471f1eb9c0 > header_size: 12324 > notes64: 56471f1eba00 > load64: 56471f1eba38 > notes32: 0 > load32: 0 > vmcoreinfo: 0 > size_vmcoreinfo: 0 > > Elf64_Phdr: > p_type: 4 (PT_NOTE) > p_flags: 0 > p_offset: 2a8 > p_vaddr: 0 > p_paddr: 0 > p_filesz: 11644 > p_memsz: 0 > p_align: 0 > > Elf64_Phdr: > p_type: 1 (PT_LOAD) > p_flags: 7 > p_offset: 7fffaa404000 > p_vaddr: ffffffffaa400000 > p_paddr: b8600000 > p_filesz: 33751040 > p_memsz: 33751040 > p_align: 4096 > > Elf64_Phdr: > p_type: 1 (PT_LOAD) > p_flags: 7 > p_offset: 286600004000 > p_vaddr: ffffa86600000000 > p_paddr: ffffffffffffffff > p_filesz: 35184372088831 > p_memsz: 35184372088831 > p_align: 4096 > > Elf64_Phdr: > p_type: 1 (PT_LOAD) > p_flags: 7 > p_offset: 7fffc0004000 > p_vaddr: ffffffffc0000000 > p_paddr: ffffffffffffffff > p_filesz: 1056964608 > p_memsz: 1056964608 > p_align: 4096 > > Elf64_Phdr: > p_type: 1 (PT_LOAD) > p_flags: 7 > p_offset: 126ac0005000 > p_vaddr: ffff926ac0001000 > p_paddr: 1000 > p_filesz: 647168 > p_memsz: 647168 > p_align: 4096 > > Elf64_Phdr: > p_type: 1 (PT_LOAD) > p_flags: 7 > p_offset: 4d8880004000 > p_vaddr: ffffcd8880000000 > p_paddr: ffffffffffffffff > p_filesz: 12288 > p_memsz: 12288 > p_align: 4096 > > Elf64_Phdr: > p_type: 1 (PT_LOAD) > p_flags: 7 > p_offset: 126ac0104000 > p_vaddr: ffff926ac0100000 > p_paddr: 100000 > p_filesz: 12902400 > p_memsz: 12902400 > p_align: 4096 > > Elf64_Phdr: > p_type: 1 (PT_LOAD) > p_flags: 7 > p_offset: 4d8880008000 > p_vaddr: ffffcd8880004000 > p_paddr: ffffffffffffffff > p_filesz: 204800 > p_memsz: 204800 > p_align: 4096 > > Elf64_Phdr: > p_type: 1 (PT_LOAD) > p_flags: 7 > p_offset: 126ac0d53000 > p_vaddr: ffff926ac0d4f000 > p_paddr: d4f000 > p_filesz: 3207118848 > p_memsz: 3207118848 > p_align: 4096 > > Elf64_Phdr: > p_type: 1 (PT_LOAD) > p_flags: 7 > p_offset: 126bc0004000 > p_vaddr: ffff926bc0000000 > p_paddr: 100000000 > p_filesz: 4294967296 > p_memsz: 4294967296 > p_align: 4096 > > Elf64_Phdr: > p_type: 1 (PT_LOAD) > p_flags: 7 > p_offset: 4d8884004000 > p_vaddr: ffffcd8884000000 > p_paddr: ffffffffffffffff > p_filesz: 67108864 > p_memsz: 67108864 > p_align: 4096 > > Elf64_Nhdr: > n_namesz: 5 ("CORE") > n_descsz: 336 > n_type: 1 (NT_PRSTATUS) > > Elf64_Nhdr: > n_namesz: 5 ("CORE") > n_descsz: 136 > n_type: 3 (NT_PRPSINFO) > > Elf64_Nhdr: > n_namesz: 5 ("CORE") > n_descsz: 7808 > n_type: 4 (NT_TASKSTRUCT) > > Elf64_Nhdr: > n_namesz: 11 ("VMCOREINFO") > n_descsz: 3279 > n_type: 0 (unknown) > > OSRELEASE=6.1.118-yocto-standard > BUILD-ID=1400000003000000474e5500a343709706409b9c > PAGESIZE=4096 > SYMBOL(init_uts_ns)=ffffffffac037a80 > OFFSET(uts_namespace.name)=0 > SYMBOL(node_online_map)=ffffffffac06d3e8 > SYMBOL(swapper_pg_dir)=ffffffffabe0a000 > SYMBOL(_stext)=ffffffffaa400000 > SYMBOL(vmap_area_list)=ffffffffabf12fb0 > SYMBOL(mem_section)=ffff926cbfff5000 > LENGTH(mem_section)=2048 > SIZE(mem_section)=16 > OFFSET(mem_section.section_mem_map)=0 > NUMBER(SECTION_SIZE_BITS)=27 > NUMBER(MAX_PHYSMEM_BITS)=46 > SIZE(page)=64 > SIZE(pglist_data)=15616 > SIZE(zone)=1600 > SIZE(free_area)=104 > SIZE(list_head)=16 > SIZE(nodemask_t)=8 > OFFSET(page.flags)=0 > OFFSET(page._refcount)=52 > OFFSET(page.mapping)=24 > OFFSET(page.lru)=8 > OFFSET(page._mapcount)=48 > OFFSET(page.private)=40 > OFFSET(page.compound_dtor)=16 > OFFSET(page.compound_order)=17 > OFFSET(page.compound_head)=8 > OFFSET(pglist_data.node_zones)=0 > OFFSET(pglist_data.nr_zones)=14624 > OFFSET(pglist_data.node_start_pfn)=14632 > OFFSET(pglist_data.node_spanned_pages)=14648 > OFFSET(pglist_data.node_id)=14656 > OFFSET(zone.free_area)=192 > OFFSET(zone.vm_stat)=1472 > OFFSET(zone.spanned_pages)=136 > OFFSET(free_area.free_list)=0 > OFFSET(list_head.next)=0 > OFFSET(list_head.prev)=8 > OFFSET(vmap_area.va_start)=0 > OFFSET(vmap_area.list)=40 > LENGTH(zone.free_area)=11 > SYMBOL(prb)=ffffffffabe647d8 > SYMBOL(printk_rb_static)=ffffffffabe647e0 > SYMBOL(clear_seq)=ffffffffac307f20 > SIZE(printk_ringbuffer)=88 > OFFSET(printk_ringbuffer.desc_ring)=0 > OFFSET(printk_ringbuffer.text_data_ring)=48 > OFFSET(printk_ringbuffer.fail)=80 > SIZE(prb_desc_ring)=48 > OFFSET(prb_desc_ring.count_bits)=0 > OFFSET(prb_desc_ring.descs)=8 > OFFSET(prb_desc_ring.infos)=16 > OFFSET(prb_desc_ring.head_id)=24 > OFFSET(prb_desc_ring.tail_id)=32 > SIZE(prb_desc)=24 > OFFSET(prb_desc.state_var)=0 > OFFSET(prb_desc.text_blk_lpos)=8 > SIZE(prb_data_blk_lpos)=16 > OFFSET(prb_data_blk_lpos.begin)=0 > OFFSET(prb_data_blk_lpos.next)=8 > SIZE(printk_info)=88 > OFFSET(printk_info.seq)=0 > OFFSET(printk_info.ts_nsec)=8 > OFFSET(printk_info.text_len)=16 > OFFSET(printk_info.caller_id)=20 > OFFSET(printk_info.dev_info)=24 > SIZE(dev_printk_info)=64 > OFFSET(dev_printk_info.subsystem)=0 > LENGTH(printk_info_subsystem)=16 > OFFSET(dev_printk_info.device)=16 > LENGTH(printk_info_device)=48 > SIZE(prb_data_ring)=32 > OFFSET(prb_data_ring.size_bits)=0 > OFFSET(prb_data_ring.data)=8 > OFFSET(prb_data_ring.head_lpos)=16 > OFFSET(prb_data_ring.tail_lpos)=24 > SIZE(atomic_long_t)=8 > OFFSET(atomic_long_t.counter)=0 > SIZE(latched_seq)=24 > OFFSET(latched_seq.val)=8 > LENGTH(free_area.free_list)=6 > NUMBER(NR_FREE_PAGES)=0 > NUMBER(PG_lru)=4 > NUMBER(PG_private)=13 > NUMBER(PG_swapcache)=10 > NUMBER(PG_swapbacked)=19 > NUMBER(PG_slab)=9 > NUMBER(PG_hwpoison)=23 > NUMBER(PG_head_mask)=65536 > NUMBER(PAGE_BUDDY_MAPCOUNT_VALUE)=-129 > NUMBER(HUGETLB_PAGE_DTOR)=2 > NUMBER(PAGE_OFFLINE_MAPCOUNT_VALUE)=-257 > SYMBOL(kallsyms_names)=ffffffffaba0f7d8 > SYMBOL(kallsyms_num_syms)=ffffffffaba0f7d0 > SYMBOL(kallsyms_token_table)=ffffffffabbf5400 > SYMBOL(kallsyms_token_index)=ffffffffabbf5788 > SYMBOL(kallsyms_offsets)=ffffffffab9984f8 > SYMBOL(kallsyms_relative_base)=ffffffffaba0f7c8 > NUMBER(phys_base)=2384461824 > SYMBOL(init_top_pgt)=ffffffffabe0a000 > NUMBER(pgtable_l5_enabled)=0 > SYMBOL(node_data)=ffffffffac06c3a0 > LENGTH(node_data)=64 > KERNELOFFSET=29400000 > NUMBER(KERNEL_IMAGE_SIZE)=1073741824 > NUMBER(sme_mask)=0 > > readmem: read_proc_kcore() -> /proc/kcore > VMCOREINFO: NUMBER(phys_base): 2384461824 -> 8e200000 > gdb /boot/vmlinux-6.1.118-yocto-standard > GNU gdb (GDB) 10.2 > Copyright (C) 2021 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 "x86_64-wrs-linux". > Type "show configuration" for configuration details. > Find the GDB manual and other documentation resources online at: > <http://www.gnu.org/software/gdb/documentation/>;. > > For help, type "help". > Type "apropos word" to search for commands related to "word"... > GETBUF(344 -> 0) > GETBUF(1500 -> 1) > > FREEBUF(1) > FREEBUF(0) > <readmem: ffffffff8292c360, KVADDR, "page_offset_base", 8, (FOE|Q), 56471ef799c8> > <read_proc_kcore: addr: ffffffff8292c360 paddr: 90b2c360 cnt: 8> > crash: seek error: kernel virtual address: ffffffff8292c360 type: "page_offset_base" > -- > Crash-utility mailing list -- devel(a)lists.crash-utility.osci.io > To unsubscribe send an email to devel-leave(a)lists.crash-utility.osci.io > https://${domain_name}/admin/lists/devel.lists.crash-utility.osci.io/ > Contribution Guidelines: https://github.com/crash-utility/crash/wiki