diff options
author | David S. Miller <davem@davemloft.net> | 2010-04-11 02:44:30 -0700 |
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committer | David S. Miller <davem@davemloft.net> | 2010-04-11 02:44:30 -0700 |
commit | 4a1032faac94ebbf647460ae3e06fc21146eb280 (patch) | |
tree | 7f31b97beb0406faa1523e619289ad0ab07c9787 /kernel/trace/trace_event_perf.c | |
parent | ae4e8d63b5619d4d95f1d2bfa2b836caa6e62d06 (diff) | |
parent | 0eddb519b9127c73d53db4bf3ec1d45b13f844d1 (diff) |
Merge branch 'master' of /home/davem/src/GIT/linux-2.6/
Diffstat (limited to 'kernel/trace/trace_event_perf.c')
-rw-r--r-- | kernel/trace/trace_event_perf.c | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/kernel/trace/trace_event_perf.c b/kernel/trace/trace_event_perf.c index 81f691eb3a3..0565bb42566 100644 --- a/kernel/trace/trace_event_perf.c +++ b/kernel/trace/trace_event_perf.c @@ -17,7 +17,12 @@ EXPORT_SYMBOL_GPL(perf_arch_fetch_caller_regs); static char *perf_trace_buf; static char *perf_trace_buf_nmi; -typedef typeof(char [PERF_MAX_TRACE_SIZE]) perf_trace_t ; +/* + * Force it to be aligned to unsigned long to avoid misaligned accesses + * suprises + */ +typedef typeof(unsigned long [PERF_MAX_TRACE_SIZE / sizeof(unsigned long)]) + perf_trace_t; /* Count the events in use (per event id, not per instance) */ static int total_ref_count; @@ -130,6 +135,8 @@ __kprobes void *perf_trace_buf_prepare(int size, unsigned short type, char *trace_buf, *raw_data; int pc, cpu; + BUILD_BUG_ON(PERF_MAX_TRACE_SIZE % sizeof(unsigned long)); + pc = preempt_count(); /* Protect the per cpu buffer, begin the rcu read side */ @@ -152,7 +159,7 @@ __kprobes void *perf_trace_buf_prepare(int size, unsigned short type, raw_data = per_cpu_ptr(trace_buf, cpu); /* zero the dead bytes from align to not leak stack to user */ - *(u64 *)(&raw_data[size - sizeof(u64)]) = 0ULL; + memset(&raw_data[size - sizeof(u64)], 0, sizeof(u64)); entry = (struct trace_entry *)raw_data; tracing_generic_entry_update(entry, *irq_flags, pc); |