1 files changed, 13 insertions, 5 deletions

diff --git a/drivers/hv/channel_mgmt.c b/drivers/hv/channel_mgmt.c
index b60f13481bdc..5b120402d405 100644
--- a/drivers/hv/channel_mgmt.c
+++ b/drivers/hv/channel_mgmt.c
@@ -21,6 +21,7 @@
 #include <linux/cpu.h>
 #include <linux/hyperv.h>
 #include <asm/mshyperv.h>
+#include <linux/sched/isolation.h>
 
 #include "hyperv_vmbus.h"
 
@@ -638,6 +639,7 @@ static void vmbus_process_offer(struct vmbus_channel *newchannel)
 		 */
 		if (newchannel->offermsg.offer.sub_channel_index == 0) {
 			mutex_unlock(&vmbus_connection.channel_mutex);
+			cpus_read_unlock();
 			/*
 			 * Don't call free_channel(), because newchannel->kobj
 			 * is not initialized yet.
@@ -728,16 +730,20 @@ static void init_vp_index(struct vmbus_channel *channel)
 	u32 i, ncpu = num_online_cpus();
 	cpumask_var_t available_mask;
 	struct cpumask *allocated_mask;
+	const struct cpumask *hk_mask = housekeeping_cpumask(HK_TYPE_MANAGED_IRQ);
 	u32 target_cpu;
 	int numa_node;
 
 	if (!perf_chn ||
-	    !alloc_cpumask_var(&available_mask, GFP_KERNEL)) {
+	    !alloc_cpumask_var(&available_mask, GFP_KERNEL) ||
+	    cpumask_empty(hk_mask)) {
 		/*
 		 * If the channel is not a performance critical
 		 * channel, bind it to VMBUS_CONNECT_CPU.
 		 * In case alloc_cpumask_var() fails, bind it to
 		 * VMBUS_CONNECT_CPU.
+		 * If all the cpus are isolated, bind it to
+		 * VMBUS_CONNECT_CPU.
 		 */
 		channel->target_cpu = VMBUS_CONNECT_CPU;
 		if (perf_chn)
@@ -758,17 +764,19 @@ static void init_vp_index(struct vmbus_channel *channel)
 		}
 		allocated_mask = &hv_context.hv_numa_map[numa_node];
 
-		if (cpumask_equal(allocated_mask, cpumask_of_node(numa_node))) {
+retry:
+		cpumask_xor(available_mask, allocated_mask, cpumask_of_node(numa_node));
+		cpumask_and(available_mask, available_mask, hk_mask);
+
+		if (cpumask_empty(available_mask)) {
 			/*
 			 * We have cycled through all the CPUs in the node;
 			 * reset the allocated map.
 			 */
 			cpumask_clear(allocated_mask);
+			goto retry;
 		}
 
-		cpumask_xor(available_mask, allocated_mask,
-			    cpumask_of_node(numa_node));
-
 		target_cpu = cpumask_first(available_mask);
 		cpumask_set_cpu(target_cpu, allocated_mask);