* [PATCH V2 2/5] Drivers: hv: vmbus: unregister panic notifier on module unload
2015-04-23 4:31 ` [PATCH V2 1/5] Drivers: hv: vmbus: introduce vmbus_acpi_remove K. Y. Srinivasan
@ 2015-04-23 4:31 ` K. Y. Srinivasan
2015-04-23 4:31 ` [PATCH V2 3/5] hv: vmbus_free_channels(): remove the redundant free_channel() K. Y. Srinivasan
` (2 subsequent siblings)
3 siblings, 0 replies; 6+ messages in thread
From: K. Y. Srinivasan @ 2015-04-23 4:31 UTC (permalink / raw)
To: gregkh, linux-kernel, devel, olaf, apw, vkuznets, jasowang
Cc: K. Y. Srinivasan
From: Vitaly Kuznetsov <vkuznets@redhat.com>
Commit 96c1d0581d00f7abe033350edb021a9d947d8d81 ("Drivers: hv: vmbus: Add
support for VMBus panic notifier handler") introduced
atomic_notifier_chain_register() call on module load. We also need to call
atomic_notifier_chain_unregister() on module unload as otherwise the following
crash is observed when we bring hv_vmbus back:
[ 39.788877] BUG: unable to handle kernel paging request at ffffffffa00078a8
[ 39.788877] IP: [<ffffffff8109d63f>] notifier_call_chain+0x3f/0x80
...
[ 39.788877] Call Trace:
[ 39.788877] [<ffffffff8109de7d>] __atomic_notifier_call_chain+0x5d/0x90
...
[ 39.788877] [<ffffffff8109d788>] ? atomic_notifier_chain_register+0x38/0x70
[ 39.788877] [<ffffffff8109d767>] ? atomic_notifier_chain_register+0x17/0x70
[ 39.788877] [<ffffffffa002814f>] hv_acpi_init+0x14f/0x1000 [hv_vmbus]
[ 39.788877] [<ffffffff81002144>] do_one_initcall+0xd4/0x210
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
---
drivers/hv/vmbus_drv.c | 4 ++++
1 files changed, 4 insertions(+), 0 deletions(-)
diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
index 0d8d1d7..7870a90 100644
--- a/drivers/hv/vmbus_drv.c
+++ b/drivers/hv/vmbus_drv.c
@@ -1108,6 +1108,10 @@ static void __exit vmbus_exit(void)
hv_synic_clockevents_cleanup();
hv_remove_vmbus_irq();
vmbus_free_channels();
+ if (ms_hyperv.features & HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE) {
+ atomic_notifier_chain_unregister(&panic_notifier_list,
+ &hyperv_panic_block);
+ }
bus_unregister(&hv_bus);
hv_cleanup();
for_each_online_cpu(cpu)
--
1.7.4.1
^ permalink raw reply [flat|nested] 6+ messages in thread* [PATCH V2 3/5] hv: vmbus_free_channels(): remove the redundant free_channel()
2015-04-23 4:31 ` [PATCH V2 1/5] Drivers: hv: vmbus: introduce vmbus_acpi_remove K. Y. Srinivasan
2015-04-23 4:31 ` [PATCH V2 2/5] Drivers: hv: vmbus: unregister panic notifier on module unload K. Y. Srinivasan
@ 2015-04-23 4:31 ` K. Y. Srinivasan
2015-04-23 4:31 ` [PATCH V2 4/5] drivers: hv: vmbus: Get rid of some unused definitions K. Y. Srinivasan
2015-04-23 4:31 ` [PATCH V2 5/5] Drivers: hv: vmbus: Implement the protocol for tearing down vmbus state K. Y. Srinivasan
3 siblings, 0 replies; 6+ messages in thread
From: K. Y. Srinivasan @ 2015-04-23 4:31 UTC (permalink / raw)
To: gregkh, linux-kernel, devel, olaf, apw, vkuznets, jasowang
Cc: Dexuan Cui, K. Y. Srinivasan
From: Dexuan Cui <decui@microsoft.com>
free_channel() has been invoked in
vmbus_remove() -> hv_process_channel_removal(), or vmbus_remove() ->
... -> vmbus_close_internal() -> hv_process_channel_removal().
We also change to use list_for_each_entry_safe(), because the entry
is removed in hv_process_channel_removal().
This patch fixes a bug in the vmbus unload path.
Thank Dan Carpenter for finding the issue!
Signed-off-by: Dexuan Cui <decui@microsoft.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: K. Y. Srinivasan <kys@microsoft.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
---
drivers/hv/channel_mgmt.c | 11 ++++++++---
1 files changed, 8 insertions(+), 3 deletions(-)
diff --git a/drivers/hv/channel_mgmt.c b/drivers/hv/channel_mgmt.c
index 0eeb1b3..865a3af 100644
--- a/drivers/hv/channel_mgmt.c
+++ b/drivers/hv/channel_mgmt.c
@@ -212,11 +212,16 @@ void hv_process_channel_removal(struct vmbus_channel *channel, u32 relid)
void vmbus_free_channels(void)
{
- struct vmbus_channel *channel;
+ struct vmbus_channel *channel, *tmp;
+
+ list_for_each_entry_safe(channel, tmp, &vmbus_connection.chn_list,
+ listentry) {
+ /* if we don't set rescind to true, vmbus_close_internal()
+ * won't invoke hv_process_channel_removal().
+ */
+ channel->rescind = true;
- list_for_each_entry(channel, &vmbus_connection.chn_list, listentry) {
vmbus_device_unregister(channel->device_obj);
- free_channel(channel);
}
}
--
1.7.4.1
^ permalink raw reply [flat|nested] 6+ messages in thread* [PATCH V2 4/5] drivers: hv: vmbus: Get rid of some unused definitions
2015-04-23 4:31 ` [PATCH V2 1/5] Drivers: hv: vmbus: introduce vmbus_acpi_remove K. Y. Srinivasan
2015-04-23 4:31 ` [PATCH V2 2/5] Drivers: hv: vmbus: unregister panic notifier on module unload K. Y. Srinivasan
2015-04-23 4:31 ` [PATCH V2 3/5] hv: vmbus_free_channels(): remove the redundant free_channel() K. Y. Srinivasan
@ 2015-04-23 4:31 ` K. Y. Srinivasan
2015-04-23 4:31 ` [PATCH V2 5/5] Drivers: hv: vmbus: Implement the protocol for tearing down vmbus state K. Y. Srinivasan
3 siblings, 0 replies; 6+ messages in thread
From: K. Y. Srinivasan @ 2015-04-23 4:31 UTC (permalink / raw)
To: gregkh, linux-kernel, devel, olaf, apw, vkuznets, jasowang
Cc: K. Y. Srinivasan
Get rid of some unused definitions.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
---
include/linux/hyperv.h | 19 -------------------
1 files changed, 0 insertions(+), 19 deletions(-)
diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h
index 1744148..e29ccdd 100644
--- a/include/linux/hyperv.h
+++ b/include/linux/hyperv.h
@@ -389,10 +389,6 @@ enum vmbus_channel_message_type {
CHANNELMSG_INITIATE_CONTACT = 14,
CHANNELMSG_VERSION_RESPONSE = 15,
CHANNELMSG_UNLOAD = 16,
-#ifdef VMBUS_FEATURE_PARENT_OR_PEER_MEMORY_MAPPED_INTO_A_CHILD
- CHANNELMSG_VIEWRANGE_ADD = 17,
- CHANNELMSG_VIEWRANGE_REMOVE = 18,
-#endif
CHANNELMSG_COUNT
};
@@ -549,21 +545,6 @@ struct vmbus_channel_gpadl_torndown {
u32 gpadl;
} __packed;
-#ifdef VMBUS_FEATURE_PARENT_OR_PEER_MEMORY_MAPPED_INTO_A_CHILD
-struct vmbus_channel_view_range_add {
- struct vmbus_channel_message_header header;
- PHYSICAL_ADDRESS viewrange_base;
- u64 viewrange_length;
- u32 child_relid;
-} __packed;
-
-struct vmbus_channel_view_range_remove {
- struct vmbus_channel_message_header header;
- PHYSICAL_ADDRESS viewrange_base;
- u32 child_relid;
-} __packed;
-#endif
-
struct vmbus_channel_relid_released {
struct vmbus_channel_message_header header;
u32 child_relid;
--
1.7.4.1
^ permalink raw reply [flat|nested] 6+ messages in thread* [PATCH V2 5/5] Drivers: hv: vmbus: Implement the protocol for tearing down vmbus state
2015-04-23 4:31 ` [PATCH V2 1/5] Drivers: hv: vmbus: introduce vmbus_acpi_remove K. Y. Srinivasan
` (2 preceding siblings ...)
2015-04-23 4:31 ` [PATCH V2 4/5] drivers: hv: vmbus: Get rid of some unused definitions K. Y. Srinivasan
@ 2015-04-23 4:31 ` K. Y. Srinivasan
3 siblings, 0 replies; 6+ messages in thread
From: K. Y. Srinivasan @ 2015-04-23 4:31 UTC (permalink / raw)
To: gregkh, linux-kernel, devel, olaf, apw, vkuznets, jasowang
Cc: K. Y. Srinivasan
Implement the protocol for tearing down the monitor state established with
the host.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Tested-by: Vitaly Kuznetsov <vkuznets@redhat.com>
---
Changes in V2: Call vmbus_disconnect earlier - Vitaly Kuznetsov <vkuznets@redhat.com>
drivers/hv/channel_mgmt.c | 25 +++++++++++++++++++++++++
drivers/hv/connection.c | 5 +++++
drivers/hv/hyperv_vmbus.h | 2 ++
drivers/hv/vmbus_drv.c | 2 +-
include/linux/hyperv.h | 1 +
5 files changed, 34 insertions(+), 1 deletions(-)
diff --git a/drivers/hv/channel_mgmt.c b/drivers/hv/channel_mgmt.c
index 865a3af..4b9d89a 100644
--- a/drivers/hv/channel_mgmt.c
+++ b/drivers/hv/channel_mgmt.c
@@ -422,6 +422,30 @@ static void init_vp_index(struct vmbus_channel *channel, const uuid_le *type_gui
}
/*
+ * vmbus_unload_response - Handler for the unload response.
+ */
+static void vmbus_unload_response(struct vmbus_channel_message_header *hdr)
+{
+ /*
+ * This is a global event; just wakeup the waiting thread.
+ * Once we successfully unload, we can cleanup the monitor state.
+ */
+ complete(&vmbus_connection.unload_event);
+}
+
+void vmbus_initiate_unload(void)
+{
+ struct vmbus_channel_message_header hdr;
+
+ init_completion(&vmbus_connection.unload_event);
+ memset(&hdr, 0, sizeof(struct vmbus_channel_message_header));
+ hdr.msgtype = CHANNELMSG_UNLOAD;
+ vmbus_post_msg(&hdr, sizeof(struct vmbus_channel_message_header));
+
+ wait_for_completion(&vmbus_connection.unload_event);
+}
+
+/*
* vmbus_onoffer - Handler for channel offers from vmbus in parent partition.
*
*/
@@ -717,6 +741,7 @@ struct vmbus_channel_message_table_entry
{CHANNELMSG_INITIATE_CONTACT, 0, NULL},
{CHANNELMSG_VERSION_RESPONSE, 1, vmbus_onversion_response},
{CHANNELMSG_UNLOAD, 0, NULL},
+ {CHANNELMSG_UNLOAD_RESPONSE, 1, vmbus_unload_response},
};
/*
diff --git a/drivers/hv/connection.c b/drivers/hv/connection.c
index b27220a..acd50e9 100644
--- a/drivers/hv/connection.c
+++ b/drivers/hv/connection.c
@@ -227,6 +227,11 @@ cleanup:
void vmbus_disconnect(void)
{
+ /*
+ * First send the unload request to the host.
+ */
+ vmbus_initiate_unload();
+
if (vmbus_connection.work_queue) {
drain_workqueue(vmbus_connection.work_queue);
destroy_workqueue(vmbus_connection.work_queue);
diff --git a/drivers/hv/hyperv_vmbus.h b/drivers/hv/hyperv_vmbus.h
index 138d663..cddc0c9 100644
--- a/drivers/hv/hyperv_vmbus.h
+++ b/drivers/hv/hyperv_vmbus.h
@@ -647,6 +647,7 @@ struct vmbus_connection {
atomic_t next_gpadl_handle;
+ struct completion unload_event;
/*
* Represents channel interrupts. Each bit position represents a
* channel. When a channel sends an interrupt via VMBUS, it finds its
@@ -741,6 +742,7 @@ void hv_vss_onchannelcallback(void *);
int hv_fcopy_init(struct hv_util_service *);
void hv_fcopy_deinit(void);
void hv_fcopy_onchannelcallback(void *);
+void vmbus_initiate_unload(void);
static inline void hv_poll_channel(struct vmbus_channel *channel,
void (*cb)(void *))
diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
index 7870a90..2b56260 100644
--- a/drivers/hv/vmbus_drv.c
+++ b/drivers/hv/vmbus_drv.c
@@ -1106,6 +1106,7 @@ static void __exit vmbus_exit(void)
vmbus_connection.conn_state = DISCONNECTED;
hv_synic_clockevents_cleanup();
+ vmbus_disconnect();
hv_remove_vmbus_irq();
vmbus_free_channels();
if (ms_hyperv.features & HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE) {
@@ -1118,7 +1119,6 @@ static void __exit vmbus_exit(void)
smp_call_function_single(cpu, hv_synic_cleanup, NULL, 1);
acpi_bus_unregister_driver(&vmbus_acpi_driver);
hv_cpu_hotplug_quirk(false);
- vmbus_disconnect();
}
diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h
index e29ccdd..ea93486 100644
--- a/include/linux/hyperv.h
+++ b/include/linux/hyperv.h
@@ -389,6 +389,7 @@ enum vmbus_channel_message_type {
CHANNELMSG_INITIATE_CONTACT = 14,
CHANNELMSG_VERSION_RESPONSE = 15,
CHANNELMSG_UNLOAD = 16,
+ CHANNELMSG_UNLOAD_RESPONSE = 17,
CHANNELMSG_COUNT
};
--
1.7.4.1
^ permalink raw reply [flat|nested] 6+ messages in thread