I have upgraded my Sun Blade 100 to latest mainline, and when it booted I hit an oops. Relevant bits from the oops: Mount-cache hash table entries: 512 Performance events: perf (null) <<<<<<<<<<<<<<<<<<< Unable to handle kernel NULL pointer dereference tsk->{mm,active_mm}->context = 0000000000000000 tsk->{mm,active_mm}->pgd = fffff800003e4634 \|/ ____ \|/ "@'/ .. \`@" /_| \__/ |_\ \__U_/ swapper(1): Oops [#1] TSTATE: 0000004480001606 TPC: 000000000055c180 TNPC: 000000000055c184 Y: 00000000 Not tainted TPC: <strcmp+0x0/0x40> g0: fffff8000f03f800 g1: 00000000007df800 g2: 000000000078f918 g3: 0000000000799168 g4: fffff8000f0358c0 g5: fffff80000c22000 g6: fffff8000f038000 g7: 0000000000000001 o0: 0000000000000000 o1: 000000000073b050 o2: 0000000000000001 o3: 0000000000000001 o4: fffff8000f0356c8 o5: 0000000000000000 sp: fffff8000f03b531 ret_pc: 00000000007b9e30 RPC: <init_hw_perf_events+0x30/0x168> l0: 0000000000000000 l1: 00000000007e0a80 l2: 00000000007e2140 l3: 0000000000000001 l4: 0000000000000000 l5: 0000000000000000 l6: 0000000000000000 l7: 0000000000777b78 i0: fffff80001402a80 i1: 0000000000000000 i2: 0000000000000001 i3: 0000000000000001 i4: 0000000000000000 i5: 0000000000000005 i6: fffff8000f03b5e1 i7: 00000000007b41c8 I7: <do_one_initcall+0x68/0x140> The line mared "<<<<<<<<<<<<<" is added by my printf debugging. It shows that sparc_pmu_type is NULL. sparc_pmu_type is set in cpu_type_probe(void) which is: arch_initcall(cpu_type_probe); But init_hw_perf_events() is: early_initcall(init_hw_perf_events); So we end up calling init_hw_perf_events() before we call cpu_type_probe(), and sparc_pmu_type is not set. This was introduced by: "perf, arch: Cleanup perf-pmu init vs lockup-detector" - 004417a6d468e24399e383645c068b498eed84ad I did not see any obvious fix. (To avoid it is simple - I can disable it in my config). Sam -- To unsubscribe from this list: send the line "unsubscribe sparclinux" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html