forked from Minki/linux
569d6557ab
When debug preempt is enabled, preempt_disable() can be traced by function and function graph tracing. There's a place in the function graph tracer that calls trace_clock() which eventually calls cycles_2_ns() outside of the recursion protection. When cycles_2_ns() calls preempt_disable() it gets traced and the graph tracer will go into a recursive loop causing a crash or worse, a triple fault. Simple fix is to use preempt_disable_notrace() in cycles_2_ns, which makes sense because the preempt_disable() tracing may use that code too, and it tracing it, even with recursion protection is rather pointless. Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/20140204141315.2a968a72@gandalf.local.home Signed-off-by: Ingo Molnar <mingo@kernel.org> |
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| boot | ||
| configs | ||
| crypto | ||
| ia32 | ||
| include | ||
| kernel | ||
| kvm | ||
| lguest | ||
| lib | ||
| math-emu | ||
| mm | ||
| net | ||
| oprofile | ||
| pci | ||
| platform | ||
| power | ||
| realmode | ||
| syscalls | ||
| tools | ||
| um | ||
| vdso | ||
| video | ||
| xen | ||
| .gitignore | ||
| Kbuild | ||
| Kconfig | ||
| Kconfig.cpu | ||
| Kconfig.debug | ||
| Makefile | ||
| Makefile_32.cpu | ||
| Makefile.um | ||