On 22.12.10 20:32:57, Robert Richter wrote: > On 21.12.10 18:44:44, [email protected] wrote:
> > Subject: arch/x86/oprofile/op_model_amd.c: perform initialisation on a > > single CPU > > From: Andrew Morton <[email protected]> > > > > [ 7.034377] BUG: using smp_processor_id() in preemptible [00000000] code: > > modprobe/483 > > [ 7.034385] caller is setup_APIC_eilvt+0x155/0x180 > > [ 7.034389] Pid: 483, comm: modprobe Not tainted 2.6.37-rc1-20101110+ #1 > > [ 7.034392] Call Trace: > > [ 7.034400] [<ffffffff812a2b72>] debug_smp_processor_id+0xd2/0xf0 > > [ 7.034404] [<ffffffff8101e985>] setup_APIC_eilvt+0x155/0x180 > > [ 7.034413] [<ffffffffa002e168>] op_amd_init+0x88/0x2b0 [oprofile] > > [ 7.034420] [<ffffffffa0043000>] ? oprofile_init+0x0/0x42 [oprofile] > > [ 7.034425] [<ffffffffa0043315>] op_nmi_init+0x249/0x2af [oprofile] > > [ 7.034431] [<ffffffffa00430b4>] oprofile_arch_init+0x11/0x29 [oprofile] > > [ 7.034437] [<ffffffffa0043010>] oprofile_init+0x10/0x42 [oprofile] > > [ 7.034441] [<ffffffff810001e3>] do_one_initcall+0x43/0x170 > > [ 7.034445] [<ffffffff8108a52a>] sys_init_module+0xba/0x200 > > [ 7.034449] [<ffffffff8100285b>] system_call_fastpath+0x16/0x1b > > > > Not sure if it fixes a real bug - presumably not, if all CPUs are the same. > > The IBS init code checks some MSR and APIC register settings which > should be the same on all CPUs. However, smp_processor_id() is used > for diagnostics reasons to report the cpu number in case of errors. > It is better to disable preemption here to avoid switching between > cpus while running we init code, though it should be save anyway. > > The code that enables and sets up IBS on each cpu uses hotplug > notifiers and on_each_cpu() protected with get_/put_online_cpus() > which should be ok. > > > > > Addresses https://bugzilla.kernel.org/show_bug.cgi?id=22812 > > > > Reported-by: <[email protected]> > > Cc: "Rafael J. Wysocki" <[email protected]> > > Cc: Dan Carpenter <[email protected]> > > Cc: Robert Richter <[email protected]> > > Cc: Ingo Molnar <[email protected]> > > Cc: <[email protected]> [2.6.37.x] > > Signed-off-by: Andrew Morton <[email protected]> > > --- > > > > arch/x86/oprofile/op_model_amd.c | 6 ++++++ > > 1 file changed, 6 insertions(+) Patch applied to git://git.kernel.org/pub/scm/linux/kernel/git/rric/oprofile.git urgent Thanks Andrew, -Robert -- Advanced Micro Devices, Inc. Operating System Research Center _______________________________________________ stable mailing list [email protected] http://linux.kernel.org/mailman/listinfo/stable
