4.19-stable review patch. If anyone has any objections, please let me know.
------------------
From: Naman Jain <namjain@xxxxxxxxxxxxxxxxxxx>
commit 6fd28941447bf2c8ca0f26fda612a1cabc41663f upstream.
Rescind offer handling relies on rescind callbacks for some of the
resources cleanup, if they are registered. It does not unregister
vmbus device for the primary channel closure, when callback is
registered. Without it, next onoffer does not come, rescind flag
remains set and device goes to unusable state.
Add logic to unregister vmbus for the primary channel in rescind callback
to ensure channel removal and relid release, and to ensure that next
onoffer can be received and handled properly.
Cc: stable@xxxxxxxxxxxxxxx
Fixes: ca3cda6fcf1e ("uio_hv_generic: add rescind support")
Signed-off-by: Naman Jain <namjain@xxxxxxxxxxxxxxxxxxx>
Reviewed-by: Saurabh Sengar <ssengar@xxxxxxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20240829071312.1595-3-namjain@xxxxxxxxxxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/hv/vmbus_drv.c | 1 +
drivers/uio/uio_hv_generic.c | 8 ++++++++
2 files changed, 9 insertions(+)
--- a/drivers/hv/vmbus_drv.c
+++ b/drivers/hv/vmbus_drv.c
@@ -1973,6 +1973,7 @@ acpi_walk_err:
vmbus_acpi_remove(device);
return ret_val;
}
+EXPORT_SYMBOL_GPL(vmbus_device_unregister);
static const struct acpi_device_id vmbus_acpi_device_ids[] = {
{"VMBUS", 0},
--- a/drivers/uio/uio_hv_generic.c
+++ b/drivers/uio/uio_hv_generic.c
@@ -119,6 +119,14 @@ static void hv_uio_rescind(struct vmbus_
/* Wake up reader */
uio_event_notify(&pdata->info);
+
+ /*
+ * With rescind callback registered, rescind path will not unregister the device
+ * from vmbus when the primary channel is rescinded.
+ * Without it, rescind handling is incomplete and next onoffer msg does not come.
+ * Unregister the device from vmbus here.
+ */
+ vmbus_device_unregister(channel->device_obj);
}
/* Sysfs API to allow mmap of the ring buffers
