[Crash-utility] [PATCH 0/4] To support module percpu symbol
Hi,
The crash utility could not get module percpu symbols.
Since percpu symbols are not included in kallsyms nor module_core area,
they were not found out in module_init().
However, symbols are existing in module object file
.data..percpu (legacy kernel revision .data.percpu) section,
load_module_symbols() can find and resolve them.
(percpu symbols exist in mod_load_symtable, not in mod_ext_symtable)
'p' command is also updated to be made redundant legacy per_cpu__ prefix.
Note:
I have not tested these paches enough over any arch or kernel revisions,
also any distros.
Just have been tested x86 (64bit) with linux-2.6.10 and linux-2.6.35.
This is my first post to crash utility.
I don't understand well the manner of this mailing list.
(I'm sorry if there's anything wrong)
Thanks,
Toshi.
-----------------------------------------------------------------------------
CHANGES: module percpu symbols are resolved while module object loading.
cmd_p() can read percpu syombols without prefix in legacy environs.
SRPM: crash-5.0.9-0.src.rpm
TEST#1: Result on linux-2.6.10 x86(64) SMP(4 CPUs) * with test module
[before]
crash> sym -m test | grep abc
crash> p abc
p: gdb request failed: p abc
[after]
crash> sym -m test | grep abc
ffffffff80871928 (d) per_cpu__abc
crash> sym abc
symbol not found: abc
possible alternatives:
ffffffff80871928 (d) per_cpu__abc
crash> p abc
PER-CPU DATA TYPE:
int per_cpu__abc;
PER-CPU ADDRESSES:
[0]: 10008af0888
[1]: 10008b00888
[2]: 10008b10888
[3]: 10008b20888
TEST#2: Result on linux-2.6.35 x86(64) SMP (8 CPUs) * with KVM modules
crash> mod | grep kvm
ffffffffa0035c40 kvm_intel 39368
/lib/modules/2.6.35/kernel/arch/x86/kvm/kvm-intel.ko
ffffffffa008dba0 kvm 175160 /lib/modules/2.6.35/kernel/arch/x86/kvm/kvm.ko
[before]
crash> sym -m kvm_intel | grep vcpus_on_cpu
crash> p vcpus_on_cpu
p: gdb request failed: p vcpus_on_cpu
[after]
crash> sym -m kvm_intel | grep vcpus_on_cpu
12a40 (d) vcpus_on_cpu
crash> p vcpus_on_cpu
PER-CPU DATA TYPE:
struct list_head vcpus_on_cpu;
PER-CPU ADDRESSES:
[0]: ffff880001812a40
[1]: ffff880001852a40
[2]: ffff880001892a40
[3]: ffff8800018d2a40
[4]: ffff880001912a40
[5]: ffff880001952a40
[6]: ffff880001992a40
[7]: ffff8800019d2a40
Toshikazu Nakayama (4):
Add percpu member.
module's percpu basic procedure.
expand percpu area.
update cmd_p().
defs.h | 2 ++
kernel.c | 1 +
symbols.c | 50 +++++++++++++++++++++++++++++++++++++++++++++-----
3 files changed, 48 insertions(+), 5 deletions(-)
--
1.7.3.2.161.g3089c