Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Merge tag 'trace-v5.16-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fixes from Steven Rostedt:
"Two locking fixes:
- Add mutex protection to ring_buffer_reset()
- Fix deadlock in modify_ftrace_direct_multi()"
* tag 'trace-v5.16-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
ftrace/direct: Fix lockup in modify_ftrace_direct_multi
ring-buffer: Protect ring_buffer_reset() from reentrancy
+7
-1
+2
-1
kernel/trace/ftrace.c
+2
-1
kernel/trace/ftrace.c
···
5602
5602
}
5603
5603
}
5604
5604
5605
+
mutex_unlock(&ftrace_lock);
5606
+
5605
5607
/* Removing the tmp_ops will add the updated direct callers to the functions */
5606
5608
unregister_ftrace_function(&tmp_ops);
5607
5609
5608
-
mutex_unlock(&ftrace_lock);
5609
5610
out_direct:
5610
5611
mutex_unlock(&direct_mutex);
5611
5612
return err;
+5
kernel/trace/ring_buffer.c
+5
kernel/trace/ring_buffer.c
···
5228
5228
struct ring_buffer_per_cpu *cpu_buffer;
5229
5229
int cpu;
5230
5230
5231
+
/* prevent another thread from changing buffer sizes */
5232
+
mutex_lock(&buffer->mutex);
5233
+
5231
5234
for_each_buffer_cpu(buffer, cpu) {
5232
5235
cpu_buffer = buffer->buffers[cpu];
5233
5236
···
5249
5246
atomic_dec(&cpu_buffer->record_disabled);
5250
5247
atomic_dec(&cpu_buffer->resize_disabled);
5251
5248
}
5249
+
5250
+
mutex_unlock(&buffer->mutex);
5252
5251
}
5253
5252
EXPORT_SYMBOL_GPL(ring_buffer_reset);
5254
5253