| Message ID | 20240604050940.859909-2-mhklinux@outlook.com (mailing list archive) |
|---|---|
| State | Not Applicable |
| Headers | show |
| Series | Hyper-V guests use Linux IRQs for channel interrupts | expand |
On Mon, Jun 03, 2024 at 10:09:29PM -0700, mhkelley58@gmail.com wrote: > From: Michael Kelley <mhklinux@outlook.com> > > Because Hyper-V doesn't know ahead-of-time what operating system will be > running in a guest VM, it may offer to Linux guests VMBus devices that are > intended for use only in Windows guests. Currently in Linux, VMBus > channels are created for these devices, and they are processed by > vmbus_device_register(). While nothing further happens because no matching > driver is found, the channel continues to exist. > > To avoid having the spurious channel, drop such devices immediately in > vmbus_onoffer(), based on identifying the device in the > vmbus_unsupported_devs table. If Hyper-V should issue a rescind request > for the device, no matching channel will be found and the rescind will > also be ignored. > > Since unsupported devices are dropped early, the check for unsupported > devices in hv_get_dev_type() is redundant. Remove it. > > Signed-off-by: Michael Kelley <mhklinux@outlook.com> Acked-by: Wei Liu <wei.liu@kernel.org>
diff --git a/drivers/hv/channel_mgmt.c b/drivers/hv/channel_mgmt.c index 3c6011a48dab..a216a0aede73 100644 --- a/drivers/hv/channel_mgmt.c +++ b/drivers/hv/channel_mgmt.c @@ -203,7 +203,7 @@ static u16 hv_get_dev_type(const struct vmbus_channel *channel) const guid_t *guid = &channel->offermsg.offer.if_type; u16 i; - if (is_hvsock_channel(channel) || is_unsupported_vmbus_devs(guid)) + if (is_hvsock_channel(channel)) return HV_UNKNOWN; for (i = HV_IDE; i < HV_UNKNOWN; i++) { @@ -1036,6 +1036,16 @@ static void vmbus_onoffer(struct vmbus_channel_message_header *hdr) trace_vmbus_onoffer(offer); + /* + * Hyper-V may offer pseudo-devices with functionality intended for + * Windows guests. Silently ignore them. There's no value in + * cluttering dmesg with error messages. + */ + if (is_unsupported_vmbus_devs(&offer->offer.if_type)) { + atomic_dec(&vmbus_connection.offer_in_progress); + return; + } + if (!vmbus_is_valid_offer(offer)) { pr_err_ratelimited("Invalid offer %d from the host supporting isolation\n", offer->child_relid);