>My test is a 1 TiB dump of a Linux system that has set mem=1G. > >With makedumpfile 1.5.3 I see the following stack backtrace: > >(gdb) bt >#0 vtop_s390x (vaddr=2251803034918936) at ./arch/s390x.c:236 >#1 0x000000008001de44 in vaddr_to_paddr_s390x (vaddr=2251803034918936) > at ./arch/s390x.c:300 >#2 0x000000008001fb50 in readmem (type_addr=0, addr=2251803034918936, > bufptr=0x3ffffff6cf0, size=32768) at makedumpfile.c:349 >#3 0x0000000080034cf2 in __exclude_unnecessary_pages ( > mem_map=2251803034918936, pfn_start=16777216, pfn_end=16842752) > at makedumpfile.c:4189 >#4 0x0000000080035716 in exclude_unnecessary_pages_cyclic () > at makedumpfile.c:4349 >#5 0x00000000800358e4 in update_cyclic_region (pfn=0) at makedumpfile.c:4380 >#6 0x00000000800384e0 in get_num_dumpable_cyclic () at makedumpfile.c:5060 >#7 0x0000000080036850 in create_dump_bitmap () at makedumpfile.c:4585 >#8 0x00000000800429c8 in create_dumpfile () at makedumpfile.c:7533 >#9 0x00000000800490fc in main (argc=5, argv=0x3fffffff3d8) > at makedumpfile.c:8651 > >Looks like makdumpfile wants to read a virtual address 2251803034918936 >(hex 0x80000C0002018) which can't be resolved by the three level kernel >page table (max is 4 TiB here). > >In the __exclude_unnecessary_pages() function the variables have the >following values: > >(gdb) print pfn_end >$1 = 16842752 >(gdb) print pfn >$2 = 16777216 >(gdb) print pfn_start >$3 = 16777216 >(gdb) print mem_map >$4 = 2251803034918936 > > I would appreciate any hints! What were these values when you didn't specify mem=1G ? The mem_map information can be shown with -D option like below: $ makedumpfile -D -cd31 vmcore dumpfile ... Memory type : SPARSEMEM mem_map (0) mem_map : f6d7f000 pfn_start : 0 pfn_end : 20000 mem_map (1) mem_map : f697f000 pfn_start : 20000 pfn_end : 40000 ... Could you show me both log of mem=1G and log of no mem= option ? The difference may help us. BTW, is the command below the actual command line you used ? makedumpfile -c -d 31 vmcore dump.kdump If yes, the dumpfile must have VMOCREINFO since you didn't specify neither -x nor -i option, i.e. the s390 dump tool generates a PT_NOTE entry as VMCOREINFO, really ? Thanks Atsushi Kumagai