Re: [Crash-utility] crash: cannot resolve "init_task_union"

Dave Anderson wrote: > On a RHEL5 x86: > > crash> sym -q __per_cpu | grep -e start -e end > c03100a0 (A) __per_cpu_start > c0315ae4 (A) __per_cpu_end > crash> > > But on your RHEL5 ppc64 kernel: > > # nm -Bn vmlinux | grep __per_cpu > c000000000430100 D __per_cpu_start > c0000000004356f0 D __per_cpu_end > # > > So if you remove the two "type == 'A'" qualifiers > from the if statement above, does it work OK? > Dave , thanks for the hint. Yes these symbols are of type D on PPC64 machine. Infact after checking on latest RHEL5 kernels [ with relocatable support ] this is the case with even other archs also. [root@llm19 boot]# cat System.map-2.6.18-1.2767.el5 | grep __per_cpu_ c065dd2c r __ksymtab___per_cpu_offset c0663c64 r __kcrctab___per_cpu_offset c0666c12 r __kstrtab___per_cpu_offset c06e6b80 D __per_cpu_offset c077d100 D __per_cpu_start c0781de4 D __per_cpu_end [root@llm19 boot]# uname -i i386 [root@llm19 boot]#

So this probably can be a generic problem affecting other arch's also. Thanks for the help. Attached here is a patch to fix this problem. Let me know if it's ok. Thanks -Sachin

* On a UP machine running SMP kernel, crash fails while reading idle tasks * from per cpu data. Signed-off-by : Sachin Sant <sachinp(a)in.ibm.com&gt; --- ------------------------------------------------------------------------------------------------------------------------ * On a UP machine running SMP kernel, crash fails while reading idle tasks * from per cpu data. Signed-off-by : Sachin Sant <sachinp(a)in.ibm.com&gt; --- diff -Naurp crash-4.0-3.16/kernel.c crash-4.0-3.16-new/kernel.c --- crash-4.0-3.16/kernel.c 2006-12-22 01:24:11.000000000 +0530 +++ crash-4.0-3.16-new/kernel.c 2007-01-05 10:49:39.000000000 +0530 @@ -114,7 +114,8 @@ kernel_init() if ((sp1 = symbol_search("__per_cpu_start")) && (sp2 = symbol_search("__per_cpu_end")) && - (sp1->type == 'A') && (sp2->type == 'A') && + (sp1->type == 'A' || sp1->type == 'D') && + (sp2->type == 'A' || sp2->type == 'D') && (sp2->value > sp1->value)) kt->flags |= SMP|PER_CPU_OFF;