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| author | David S. Miller <davem@davemloft.net> | 2014-08-12 00:38:46 +0200 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2014-08-12 05:45:12 +0200 |
| commit | 8bccf5b313180faefce38e0d1140f76e0f327d28 (patch) | |
| tree | ed8d8f8c5696526f1ecf6fccd94680fe166427f4 /arch/sparc/kernel/smp_64.c | |
| parent | sparc64: Do not disable interrupts in nmi_cpu_busy() (diff) | |
| download | linux-8bccf5b313180faefce38e0d1140f76e0f327d28.tar.xz linux-8bccf5b313180faefce38e0d1140f76e0f327d28.zip | |
sparc64: Fix pcr_ops initialization and usage bugs.
Christopher reports that perf_event_print_debug() can crash in uniprocessor
builds. The crash is due to pcr_ops being NULL.
This happens because pcr_arch_init() is only invoked by smp_cpus_done() which
only executes in SMP builds.
init_hw_perf_events() is closely intertwined with pcr_ops being setup properly,
therefore:
1) Call pcr_arch_init() early on from init_hw_perf_events(), instead of
from smp_cpus_done().
2) Do not hook up a PMU type if pcr_ops is NULL after pcr_arch_init().
3) Move init_hw_perf_events to a later initcall so that it we will be
sure to invoke pcr_arch_init() after all cpus are brought up.
Finally, guard the one naked sequence of pcr_ops dereferences in
__global_pmu_self() with an appropriate NULL check.
Reported-by: Christopher Alexander Tobias Schulze <cat.schulze@alice-dsl.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to '')
| -rw-r--r-- | arch/sparc/kernel/smp_64.c | 1 |
1 files changed, 0 insertions, 1 deletions
diff --git a/arch/sparc/kernel/smp_64.c b/arch/sparc/kernel/smp_64.c index 41aa2478f3ca..f7ba87543e5f 100644 --- a/arch/sparc/kernel/smp_64.c +++ b/arch/sparc/kernel/smp_64.c @@ -1383,7 +1383,6 @@ void __cpu_die(unsigned int cpu) void __init smp_cpus_done(unsigned int max_cpus) { - pcr_arch_init(); } void smp_send_reschedule(int cpu) |