[PATCH 1/1] drivers/hv: cleanup synic msrs if vmbus connect failed

[PATCH 1/1] drivers/hv: cleanup synic msrs if vmbus connect failed

[Denis V. Lunev]

From: Andrey Smetanin <asmetanin@virtuozzo.com>

Before vmbus_connect() synic is setup per vcpu - this means
hypervisor receives writes at synic msr's and probably allocate
hypervisor resources per synic setup.

If vmbus_connect() failed for some reason it's neccessary to cleanup
synic setup by call hv_synic_cleanup() at each vcpu to get a chance
to free allocated resources by hypervisor per synic.

This patch does appropriate cleanup in case of vmbus_connect() failure.

Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: "K. Y. Srinivasan" <kys@microsoft.com>
CC: Haiyang Zhang <haiyangz@microsoft.com>
CC: Vitaly Kuznetsov <vkuznets@redhat.com>
---
 drivers/hv/vmbus_drv.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
index f19b6f7..3297731 100644
--- a/drivers/hv/vmbus_drv.c
+++ b/drivers/hv/vmbus_drv.c
@@ -867,7 +867,7 @@ static int vmbus_bus_init(int irq)
 	on_each_cpu(hv_synic_init, NULL, 1);
 	ret = vmbus_connect();
 	if (ret)
-		goto err_alloc;
+		goto err_connect;
 
 	if (vmbus_proto_version > VERSION_WIN7)
 		cpu_hotplug_disable();
@@ -885,6 +885,8 @@ static int vmbus_bus_init(int irq)
 
 	return 0;
 
+err_connect:
+	on_each_cpu(hv_synic_cleanup, NULL, 1);
 err_alloc:
 	hv_synic_free();
 	hv_remove_vmbus_irq();
-- 
2.1.4

Re: [PATCH 1/1] drivers/hv: cleanup synic msrs if vmbus connect failed

[Vitaly Kuznetsov]

"Denis V. Lunev" <den@openvz.org> writes:

> From: Andrey Smetanin <asmetanin@virtuozzo.com>
>
> Before vmbus_connect() synic is setup per vcpu - this means
> hypervisor receives writes at synic msr's and probably allocate
> hypervisor resources per synic setup.
>
> If vmbus_connect() failed for some reason it's neccessary to cleanup
> synic setup by call hv_synic_cleanup() at each vcpu to get a chance
> to free allocated resources by hypervisor per synic.

"to make sure it is safe to free previously allocated resources" (as we
can free them anyway)?

>
> This patch does appropriate cleanup in case of vmbus_connect() failure.
>
> Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com>
> Signed-off-by: Denis V. Lunev <den@openvz.org>
> CC: "K. Y. Srinivasan" <kys@microsoft.com>
> CC: Haiyang Zhang <haiyangz@microsoft.com>
> CC: Vitaly Kuznetsov <vkuznets@redhat.com>

Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>

> ---
>  drivers/hv/vmbus_drv.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
> index f19b6f7..3297731 100644
> --- a/drivers/hv/vmbus_drv.c
> +++ b/drivers/hv/vmbus_drv.c
> @@ -867,7 +867,7 @@ static int vmbus_bus_init(int irq)
>  	on_each_cpu(hv_synic_init, NULL, 1);
>  	ret = vmbus_connect();
>  	if (ret)
> -		goto err_alloc;
> +		goto err_connect;
>
>  	if (vmbus_proto_version > VERSION_WIN7)
>  		cpu_hotplug_disable();
> @@ -885,6 +885,8 @@ static int vmbus_bus_init(int irq)
>
>  	return 0;
>
> +err_connect:
> +	on_each_cpu(hv_synic_cleanup, NULL, 1);
>  err_alloc:
>  	hv_synic_free();
>  	hv_remove_vmbus_irq();

-- 
  Vitaly