ARC: Call trace_hardirqs_on() before enabling irqs
trace_hardirqs_on_caller() in lockdep.c expects to be called before, not after interrupts are actually enabled. The following comment in kernel/locking/lockdep.c substantiates this claim: " /* * We're enabling irqs and according to our state above irqs weren't * already enabled, yet we find the hardware thinks they are in fact * enabled.. someone messed up their IRQ state tracing. */ " An example can be found in include/linux/irqflags.h: do { trace_hardirqs_on(); raw_local_irq_enable(); } while (0) Without this change, we hit the following DEBUG_LOCKS_WARN_ON. [ 7.760000] ------------[ cut here ]------------ [ 7.760000] WARNING: CPU: 0 PID: 1 at kernel/locking/lockdep.c:2711 resume_user_mode_begin+0x48/0xf0 [ 7.770000] DEBUG_LOCKS_WARN_ON(!irqs_disabled()) [ 7.780000] Modules linked in: [ 7.780000] CPU: 0 PID: 1 Comm: init Not tainted 4.7.0-00003-gc668bb9-dirty #366 [ 7.790000] [ 7.790000] Stack Trace: [ 7.790000] arc_unwind_core.constprop.1+0xa4/0x118 [ 7.800000] warn_slowpath_fmt+0x72/0x158 [ 7.800000] resume_user_mode_begin+0x48/0xf0 [ 7.810000] ---[ end trace 6f6a7a8fae20d2f0 ]--- Signed-off-by: Daniel Mentz <danielmentz@google.com> Cc: <stable@vger.kernel.org> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Showing
Please register or sign in to comment