From: David Daney <david.daney@xxxxxxxxxx> As noted by Thomas Gleixner: commit cdbedc61c8 (mips: Use generic idle loop) broke MIPS as I did not realize that MIPS wants to invoke the wait instructions with interrupts enabled. Instead of enabling interrupts in arch_cpu_idle() as Thomas' initial patch does, we follow Linus' suggestion of doing it in the assembly code to prevent the compiler from rearranging things. Signed-off-by: David Daney <david.daney@xxxxxxxxxx> Reported-by: EunBong Song <eunb.song@xxxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Jonas Gorski <jogo@xxxxxxxxxxx> --- This is only very lightly tested, we need more testing before declaring it the definitive fix. arch/mips/kernel/genex.S | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/arch/mips/kernel/genex.S b/arch/mips/kernel/genex.S index ecb347c..57cda9a 100644 --- a/arch/mips/kernel/genex.S +++ b/arch/mips/kernel/genex.S @@ -132,12 +132,13 @@ LEAF(r4k_wait) .set noreorder /* start of rollback region */ LONG_L t0, TI_FLAGS($28) - nop andi t0, _TIF_NEED_RESCHED bnez t0, 1f nop - nop - nop + /* Enable interrupts so WAIT will complete */ + mfc0 t0, CP0_STATUS + ori t0, ST0_IE + mtc0 t0, CP0_STATUS .set mips3 wait /* end of rollback region (the region size must be power of two) */ -- 1.7.11.7
