Merge tag 'powerpc-4.3-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc fixes from Michael Ellerman:

 - Revert "Use the POWER8 Micro Partition Prefetch Engine in KVM HV on
   POWER8" from Paul
 - Handle irq_happened flag correctly in off-line loop from Paul
 - Validate rtas.entry before calling enter_rtas() from Vasant

* tag 'powerpc-4.3-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/rtas: Validate rtas.entry before calling enter_rtas()
  powerpc/powernv: Handle irq_happened flag correctly in off-line loop
  powerpc: Revert "Use the POWER8 Micro Partition Prefetch Engine in KVM HV on POWER8"

1 files changed, 24 insertions, 5 deletions

diff --git a/arch/powerpc/platforms/powernv/smp.c b/arch/powerpc/platforms/powernv/smp.c
index 8f70ba681a78..ca264833ee64 100644
--- a/arch/powerpc/platforms/powernv/smp.c
+++ b/arch/powerpc/platforms/powernv/smp.c
@@ -171,7 +171,26 @@ static void pnv_smp_cpu_kill_self(void)
 	 * so clear LPCR:PECE1. We keep PECE2 enabled.
 	 */
 	mtspr(SPRN_LPCR, mfspr(SPRN_LPCR) & ~(u64)LPCR_PECE1);
+
+	/*
+	 * Hard-disable interrupts, and then clear irq_happened flags
+	 * that we can safely ignore while off-line, since they
+	 * are for things for which we do no processing when off-line
+	 * (or in the case of HMI, all the processing we need to do
+	 * is done in lower-level real-mode code).
+	 */
+	hard_irq_disable();
+	local_paca->irq_happened &= ~(PACA_IRQ_DEC | PACA_IRQ_HMI);
+
 	while (!generic_check_cpu_restart(cpu)) {
+		/*
+		 * Clear IPI flag, since we don't handle IPIs while
+		 * offline, except for those when changing micro-threading
+		 * mode, which are handled explicitly below, and those
+		 * for coming online, which are handled via
+		 * generic_check_cpu_restart() calls.
+		 */
+		kvmppc_set_host_ipi(cpu, 0);
 
 		ppc64_runlatch_off();
 
@@ -196,20 +215,20 @@ static void pnv_smp_cpu_kill_self(void)
 		 * having finished executing in a KVM guest, then srr1
 		 * contains 0.
 		 */
-		if ((srr1 & wmask) == SRR1_WAKEEE) {
+		if (((srr1 & wmask) == SRR1_WAKEEE) ||
+		    (local_paca->irq_happened & PACA_IRQ_EE)) {
 			icp_native_flush_interrupt();
-			local_paca->irq_happened &= PACA_IRQ_HARD_DIS;
-			smp_mb();
 		} else if ((srr1 & wmask) == SRR1_WAKEHDBELL) {
 			unsigned long msg = PPC_DBELL_TYPE(PPC_DBELL_SERVER);
 			asm volatile(PPC_MSGCLR(%0) : : "r" (msg));
-			kvmppc_set_host_ipi(cpu, 0);
 		}
+		local_paca->irq_happened &= ~(PACA_IRQ_EE | PACA_IRQ_DBELL);
+		smp_mb();
 
 		if (cpu_core_split_required())
 			continue;
 
-		if (!generic_check_cpu_restart(cpu))
+		if (srr1 && !generic_check_cpu_restart(cpu))
 			DBG("CPU%d Unexpected exit while offline !\n", cpu);
 	}
 	mtspr(SPRN_LPCR, mfspr(SPRN_LPCR) | LPCR_PECE1);