Hello Daisuke, I merged your patch with mine, and have things working relatively well. One other issue comes up -- when the percpu data areas are set up, they are done with a "for_each_possible_cpu(cpu)", so your new x86_64_per_cpu_init() function (may) return more cpus than are actually online. At least that's the case with Mike's vmcore -- it's running with 2 cpus online, but the percpu data area was set up for 4. Prior to 2.6.30, it appears that only online cpus initialized their x8664_pda structures. Anyway, I guess we'll just have to scale back the cpu count based upon the contents of the cpu_online_map. I changed the x86_64_verify_symbol() function to look like this so as to only collect the __per_cpu_start/end and per_cpu__xxx symbols: /* * Accept or reject a symbol from the kernel namelist. */ static int x86_64_verify_symbol(const char *name, ulong value, char type) { if (!name || !strlen(name)) return FALSE; if (!(machdep->flags & KSYMS_START)) { if (STREQ(name, "_text") || STREQ(name, "_stext")) { machdep->flags |= KSYMS_START; if (!st->first_ksymbol) st->first_ksymbol = value; return TRUE; } else if (STREQ(name, "__per_cpu_start")) { st->flags |= PERCPU_SYMS; return TRUE; } else if ((st->flags & PERCPU_SYMS) && (STRNEQ(name, "per_cpu") || STRNEQ(name, "__per_cpu"))) return TRUE; else return FALSE; } return TRUE; } where the PERCPU_SYMS flag is held in the global symbol_table_data flags field, and where it gets used like this in symbols.c:in_ksymbol_range(): /* * Determine whether an address falls within the kernel's, or any module's, * address space. */ int in_ksymbol_range(ulong value) { if ((value >= st->symtable[0].value) && (value <= st->symtable[st->symcnt-1].value)) { if ((st->flags & PERCPU_SYMS) && (value < st->first_ksymbol)) return FALSE; else return TRUE; } if (module_symbol(value, NULL, NULL, NULL, output_radix)) return TRUE; if (machdep->value_to_symbol(value, NULL)) return TRUE; return FALSE; } This seems to (so far) clear up the inadvertent dumping of "false" value-to-symbol translations in situations like "rd -s", but allows that usage of the per_cpu_xxx symbols are arguments to symbol_value(), symbol_exists(), symbol_search(), etc. Other than that, so far I've left the rest of your patch intact, and I wanted to thank you again for the contribution. Dave