----- Original Message ----- > > Hi, > > On 08/19/2015 12:02 PM, Baoquan He wrote: > > On 08/19/15 at 09:21am, Nikolay Borisov wrote: > >> Hello, > >> > >> I've recently noticed that when creating crashdumps the dmesg is not > >> being saved. The error reported is this: "Missing the struct log size > >> export". I've tested with both kernel 4.1.1 and 3.12.28. My version of > >> kexec tools is : kexec-tools 2.0.9 released 04 June 2015. The kernel has > >> been compiled with debugging info so the respective symbol should be > >> exported but apparently it is not. Any ideas how to debug that? > > > > That would be more helpful if you can attach the 1st kernel and kdump > > kernel console log. > > I just tested with 4.1.6 with the same result. I'm sending you a link to > the bzImage in question > http://georgi.unixsol.org/cruft/tmp/bzImage-4.1.6-clouder1 ( I assume > you meant the bzImage, if you need I can provide the vmlinux as well). > Unfortunately, I couldn't figure how to obtain the log of kdump in > textual format (and didn't want to send pictures). Here are the 3 > relevant lines (from memory): > > Saving vmcore-dmesg.txt > Missing the struct log size export > Error saving vmcore-dmesg.txt. > > Yet, when I load the crashdump inside the 'crash' utility and invoke the > 'log' command the dmesg log is there. Whereas the vmcore-dmesg-incomplete.txt is empty. FYI -- the crash utility doesn't use the vmcoreinfo data for its "log" command, but you can dump the vmcore's header contents, including the vmcoreinfo strings, with the "help -n" command. For example: crash> help -n ... [ cut ] ... OSRELEASE=3.18.0-0.rc2.git2.1.slub1.fc21.x86_64 PAGESIZE=4096 SYMBOL(init_uts_ns)=ffffffff81e1b300 SYMBOL(node_online_map)=ffffffff81fe8980 SYMBOL(swapper_pg_dir)=ffffffff81e14000 SYMBOL(_stext)=ffffffff810001c8 SYMBOL(vmap_area_list)=ffffffff81efce50 SYMBOL(mem_section)=ffffffff832eb180 LENGTH(mem_section)=4096 SIZE(mem_section)=32 OFFSET(mem_section.section_mem_map)=0 SIZE(page)=64 SIZE(pglist_data)=156928 SIZE(zone)=1984 SIZE(free_area)=88 SIZE(list_head)=16 SIZE(nodemask_t)=128 OFFSET(page.flags)=0 OFFSET(page._count)=28 OFFSET(page.mapping)=8 OFFSET(page.lru)=32 OFFSET(page._mapcount)=24 OFFSET(page.private)=48 OFFSET(pglist_data.node_zones)=0 OFFSET(pglist_data.nr_zones)=156480 OFFSET(pglist_data.node_start_pfn)=156560 OFFSET(pglist_data.node_spanned_pages)=156576 OFFSET(pglist_data.node_id)=156584 OFFSET(zone.free_area)=392 OFFSET(zone.vm_stat)=1664 OFFSET(zone.spanned_pages)=120 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)=48 LENGTH(zone.free_area)=11 SYMBOL(log_buf)=ffffffff81e5f0c0 SYMBOL(log_buf_len)=ffffffff81e5f0bc SYMBOL(log_first_idx)=ffffffff831bee88 SYMBOL(log_next_idx)=ffffffff831bee78 SIZE(printk_log)=16 OFFSET(printk_log.ts_nsec)=0 OFFSET(printk_log.len)=8 OFFSET(printk_log.text_len)=10 OFFSET(printk_log.dict_len)=12 LENGTH(free_area.free_list)=5 NUMBER(NR_FREE_PAGES)=0 NUMBER(PG_lru)=5 NUMBER(PG_private)=11 NUMBER(PG_swapcache)=16 NUMBER(PG_slab)=7 NUMBER(PG_hwpoison)=23 NUMBER(PG_head_mask)=16384 NUMBER(PAGE_BUDDY_MAPCOUNT_VALUE)=-128 SYMBOL(free_huge_page)=ffffffff81239430 SYMBOL(phys_base)=ffffffff81e1b010 SYMBOL(init_level4_pgt)=ffffffff81e14000 SYMBOL(node_data)=ffffffff81fe2d40 LENGTH(node_data)=1024 KERNELOFFSET=0 CRASHTIME=141512763 ... Dave
