linux-stable.git/drivers/hv, branch v5.12.2

mm/memory_hotplug: MEMHP_MERGE_RESOURCE -> MHP_MERGE_RESOURCE

2021-02-26T17:41:00+00:00

Let's make "MEMHP_MERGE_RESOURCE" consistent with "MHP_NONE", "mhp_t" and
"mhp_flags".  As discussed recently [1], "mhp" is our internal acronym for
memory hotplug now.

[1] https://lore.kernel.org/linux-mm/c37de2d0-28a1-4f7d-f944-cfd7d81c334d@redhat.com/

Link: https://lkml.kernel.org/r/20210126115829.10909-1-david@redhat.com
Signed-off-by: David Hildenbrand 
Reviewed-by: Miaohe Lin 
Acked-by: Michael S. Tsirkin 
Reviewed-by: Oscar Salvador 
Acked-by: Wei Liu 
Reviewed-by: Pankaj Gupta 
Cc: "K. Y. Srinivasan" 
Cc: Haiyang Zhang 
Cc: Stephen Hemminger 
Cc: Jason Wang 
Cc: Boris Ostrovsky 
Cc: Juergen Gross 
Cc: Stefano Stabellini 
Cc: Michal Hocko 
Cc: Anshuman Khandual 
Cc: Wei Yang 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Revert "Drivers: hv: vmbus: Copy packets sent by Hyper-V out of the ring buffer"

2021-02-15T10:49:11+00:00

This reverts commit a8c3209998afb5c4941b49e35b513cea9050cb4a.

It is reported that the said commit caused regression in netvsc.

Reported-by: Andrea Parri (Microsoft) 
Signed-off-by: Wei Liu

Drivers: hv: vmbus: skip VMBus initialization if Linux is root

2021-02-11T08:47:06+00:00

There is no VMBus and the other infrastructures initialized in
hv_acpi_init when Linux is running as the root partition.

Signed-off-by: Wei Liu 
Reviewed-by: Pavel Tatashin 
Reviewed-by: Michael Kelley 
Link: https://lore.kernel.org/r/20210203150435.27941-4-wei.liu@kernel.org

Drivers: hv: vmbus: Enforce 'VMBus version >= 5.2' on isolated guests

2021-02-11T08:47:05+00:00

Restrict the protocol version(s) that will be negotiated with the host
to be 5.2 or greater if the guest is running isolated.  This reduces the
footprint of the code that will be exercised by Confidential VMs and
hence the exposure to bugs and vulnerabilities.

Signed-off-by: Andrea Parri (Microsoft) 
Reviewed-by: Michael Kelley 
Link: https://lore.kernel.org/r/20210201144814.2701-4-parri.andrea@gmail.com
Signed-off-by: Wei Liu

Drivers: hv: vmbus: Restrict vmbus_devices on isolated guests

2021-02-11T08:47:05+00:00

Only the VSCs or ICs that have been hardened and that are critical for
the successful adoption of Confidential VMs should be allowed if the
guest is running isolated.  This change reduces the footprint of the
code that will be exercised by Confidential VMs and hence the exposure
to bugs and vulnerabilities.

Signed-off-by: Andrea Parri (Microsoft) 
Reviewed-by: Michael Kelley 
Link: https://lore.kernel.org/r/20210201144814.2701-3-parri.andrea@gmail.com
Signed-off-by: Wei Liu

hv_utils: Fix spelling mistake "Hearbeat" -> "Heartbeat"

2021-02-11T08:47:05+00:00

There is a spelling mistake in an error message. Fix it.

Signed-off-by: Colin Ian King 
Link: https://lore.kernel.org/r/20210127233136.623465-1-colin.king@canonical.com
Signed-off-by: Wei Liu

Drivers: hv: vmbus: Add /sys/bus/vmbus/hibernation

2021-02-11T08:47:05+00:00

When a Linux VM runs on Hyper-V, if the host toolstack doesn't support
hibernation for the VM (this happens on old Hyper-V hosts like Windows
Server 2016, or new Hyper-V hosts if the admin or user doesn't declare
the hibernation intent for the VM), the VM is discouraged from trying
hibernation (because the host doesn't guarantee that the VM's virtual
hardware configuration will remain exactly the same across hibernation),
i.e. the VM should not try to set up the swap partition/file for
hibernation, etc.

x86 Hyper-V uses the presence of the virtual ACPI S4 state as the
indication of the host toolstack support for a VM. Currently there is
no easy and reliable way for the userspace to detect the presence of
the state (see https://lkml.org/lkml/2020/12/11/1097).  Add
/sys/bus/vmbus/hibernation for this purpose.

Signed-off-by: Dexuan Cui 
Reviewed-by: Michael Kelley 
Link: https://lore.kernel.org/r/20210107014552.14234-1-decui@microsoft.com
Signed-off-by: Wei Liu

Drivers: hv: vmbus: Resolve race condition in vmbus_onoffer_rescind()

2021-02-05T09:55:42+00:00

An erroneous or malicious host could send multiple rescind messages for
a same channel.  In vmbus_onoffer_rescind(), the guest maps the channel
ID to obtain a pointer to the channel object and it eventually releases
such object and associated data.  The host could time rescind messages
and lead to an use-after-free.  Add a new flag to the channel structure
to make sure that only one instance of vmbus_onoffer_rescind() can get
the reference to the channel object.

Reported-by: Juan Vazquez 
Signed-off-by: Andrea Parri (Microsoft) 
Reviewed-by: Michael Kelley 
Link: https://lore.kernel.org/r/20201209070827.29335-6-parri.andrea@gmail.com
Signed-off-by: Wei Liu

Drivers: hv: vmbus: Avoid use-after-free in vmbus_onoffer_rescind()

2021-02-05T09:55:42+00:00

When channel->device_obj is non-NULL, vmbus_onoffer_rescind() could
invoke put_device(), that will eventually release the device and free
the channel object (cf. vmbus_device_release()).  However, a pointer
to the object is dereferenced again later to load the primary_channel.
The use-after-free can be avoided by noticing that this load/check is
redundant if device_obj is non-NULL: primary_channel must be NULL if
device_obj is non-NULL, cf. vmbus_add_channel_work().

Fixes: 54a66265d6754b ("Drivers: hv: vmbus: Fix rescind handling")
Reported-by: Juan Vazquez 
Signed-off-by: Andrea Parri (Microsoft) 
Reviewed-by: Michael Kelley 
Link: https://lore.kernel.org/r/20201209070827.29335-5-parri.andrea@gmail.com
Signed-off-by: Wei Liu

Drivers: hv: vmbus: Copy the hv_message in vmbus_on_msg_dpc()

2021-02-05T09:55:42+00:00

Since the message is in memory shared with the host, an erroneous or a
malicious Hyper-V could 'corrupt' the message while vmbus_on_msg_dpc()
or individual message handlers are executing.  To prevent it, copy the
message into private memory.

Reported-by: Juan Vazquez 
Signed-off-by: Andrea Parri (Microsoft) 
Reviewed-by: Michael Kelley 
Link: https://lore.kernel.org/r/20201209070827.29335-4-parri.andrea@gmail.com
Signed-off-by: Wei Liu