Drivers: hv: vmbus: fix init_vp_index() for reloading hv_netvsc

This fixes the recent commit 3b71107d73:
Drivers: hv: vmbus: Further improve CPU affiliation logic

Without the fix, reloading hv_netvsc hangs the guest.

Signed-off-by: Dexuan Cui <decui@microsoft.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Dexuan Cui 2015-08-13 17:07:03 -07:00 committed by Greg Kroah-Hartman
parent 5964db0876
commit ca1c4b7457

View File

@ -204,6 +204,8 @@ void hv_process_channel_removal(struct vmbus_channel *channel, u32 relid)
spin_lock_irqsave(&vmbus_connection.channel_lock, flags);
list_del(&channel->listentry);
spin_unlock_irqrestore(&vmbus_connection.channel_lock, flags);
primary_channel = channel;
} else {
primary_channel = channel->primary_channel;
spin_lock_irqsave(&primary_channel->lock, flags);
@ -211,6 +213,14 @@ void hv_process_channel_removal(struct vmbus_channel *channel, u32 relid)
primary_channel->num_sc--;
spin_unlock_irqrestore(&primary_channel->lock, flags);
}
/*
* We need to free the bit for init_vp_index() to work in the case
* of sub-channel, when we reload drivers like hv_netvsc.
*/
cpumask_clear_cpu(channel->target_cpu,
&primary_channel->alloced_cpus_in_node);
free_channel(channel);
}
@ -458,6 +468,13 @@ static void init_vp_index(struct vmbus_channel *channel, const uuid_le *type_gui
continue;
}
/*
* NOTE: in the case of sub-channel, we clear the sub-channel
* related bit(s) in primary->alloced_cpus_in_node in
* hv_process_channel_removal(), so when we reload drivers
* like hv_netvsc in SMP guest, here we're able to re-allocate
* bit from primary->alloced_cpus_in_node.
*/
if (!cpumask_test_cpu(cur_cpu,
&primary->alloced_cpus_in_node)) {
cpumask_set_cpu(cur_cpu,