linux-stable.git/drivers/hv, branch v5.7.7

Drivers: hv: vmbus: Always handle the VMBus messages on CPU0

2020-06-22T07:32:32+00:00

[ Upstream commit 8a857c55420f29da4fc131adc22b12d474c48f4c ]

A Linux guest have to pick a "connect CPU" to communicate with the
Hyper-V host.  This CPU can not be taken offline because Hyper-V does
not provide a way to change that CPU assignment.

Current code sets the connect CPU to whatever CPU ends up running the
function vmbus_negotiate_version(), and this will generate problems if
that CPU is taken offine.

Establish CPU0 as the connect CPU, and add logics to prevents the
connect CPU from being taken offline.   We could pick some other CPU,
and we could pick that "other CPU" dynamically if there was a reason to
do so at some point in the future.  But for now, #defining the connect
CPU to 0 is the most straightforward and least complex solution.

While on this, add inline comments explaining "why" offer and rescind
messages should not be handled by a same serialized work queue.

Suggested-by: Dexuan Cui 
Signed-off-by: Andrea Parri (Microsoft) 
Reviewed-by: Vitaly Kuznetsov 
Link: https://lore.kernel.org/r/20200406001514.19876-2-parri.andrea@gmail.com
Reviewed-by: Michael Kelley 
Signed-off-by: Wei Liu 
Signed-off-by: Sasha Levin

Merge tag 'hyperv-fixes-signed' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux

2020-04-27T20:28:27+00:00

Pull Hyper-V fixes from Wei Liu:

 - Two patches from Dexuan fixing suspension bugs

 - Three cleanup patches from Andy and Michael

* tag 'hyperv-fixes-signed' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux:
  hyper-v: Remove internal types from UAPI header
  hyper-v: Use UUID API for exporting the GUID
  x86/hyperv: Suspend/resume the VP assist page for hibernation
  Drivers: hv: Move AEOI determination to architecture dependent code
  Drivers: hv: vmbus: Fix Suspend-to-Idle for Generation-2 VM

hyper-v: Use UUID API for exporting the GUID

2020-04-22T13:40:02+00:00

There is export_guid() function which exports guid_t to the u8 array.
Use it instead of open coding variant.

This allows to hide the uuid_t internals.

Signed-off-by: Andy Shevchenko 
Link: https://lore.kernel.org/r/20200422125937.38355-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Wei Liu

Drivers: hv: Move AEOI determination to architecture dependent code

2020-04-21T09:02:38+00:00

Hyper-V on ARM64 doesn't provide a flag for the AEOI recommendation
in ms_hyperv.hints, so having the test in architecture independent
code doesn't work. Resolve this by moving the check of the flag
to an architecture dependent helper function. No functionality is
changed.

Signed-off-by: Michael Kelley 
Link: https://lore.kernel.org/r/20200420164926.24471-1-mikelley@microsoft.com
Signed-off-by: Wei Liu

Drivers: hv: vmbus: Fix Suspend-to-Idle for Generation-2 VM

2020-04-14T20:16:35+00:00

Before the hibernation patchset (e.g. f53335e3289f), in a Generation-2
Linux VM on Hyper-V, the user can run "echo freeze > /sys/power/state" to
freeze the system, i.e. Suspend-to-Idle. The user can press the keyboard
or move the mouse to wake up the VM.

With the hibernation patchset, Linux VM on Hyper-V can hibernate to disk,
but Suspend-to-Idle is broken: when the synthetic keyboard/mouse are
suspended, there is no way to wake up the VM.

Fix the issue by not suspending and resuming the vmbus devices upon
Suspend-to-Idle.

Fixes: f53335e3289f ("Drivers: hv: vmbus: Suspend/resume the vmbus itself for hibernation")
Cc: stable@vger.kernel.org
Reviewed-by: Michael Kelley 
Signed-off-by: Dexuan Cui 
Link: https://lore.kernel.org/r/1586663435-36243-1-git-send-email-decui@microsoft.com
Signed-off-by: Wei Liu

Merge tag 'hyperv-fixes-signed' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux

2020-04-14T18:58:04+00:00

Pull hyperv fixes from Wei Liu:

 - a series from Tianyu Lan to fix crash reporting on Hyper-V

 - three miscellaneous cleanup patches

* tag 'hyperv-fixes-signed' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux:
  x86/Hyper-V: Report crash data in die() when panic_on_oops is set
  x86/Hyper-V: Report crash register data when sysctl_record_panic_msg is not set
  x86/Hyper-V: Report crash register data or kmsg before running crash kernel
  x86/Hyper-V: Trigger crash enlightenment only once during system crash.
  x86/Hyper-V: Free hv_panic_page when fail to register kmsg dump
  x86/Hyper-V: Unload vmbus channel in hv panic callback
  x86: hyperv: report value of misc_features
  hv_debugfs: Make hv_debug_root static
  hv: hyperv_vmbus.h: Replace zero-length array with flexible-array member

x86/Hyper-V: Report crash data in die() when panic_on_oops is set

2020-04-11T16:19:07+00:00

When oops happens with panic_on_oops unset, the oops
thread is killed by die() and system continues to run.
In such case, guest should not report crash register
data to host since system still runs. Check panic_on_oops
and return directly in hyperv_report_panic() when the function
is called in the die() and panic_on_oops is unset. Fix it.

Fixes: 7ed4325a44ea ("Drivers: hv: vmbus: Make panic reporting to be more useful")
Signed-off-by: Tianyu Lan 
Reviewed-by: Michael Kelley 
Link: https://lore.kernel.org/r/20200406155331.2105-7-Tianyu.Lan@microsoft.com
Signed-off-by: Wei Liu

x86/Hyper-V: Report crash register data when sysctl_record_panic_msg is not set

2020-04-11T16:19:06+00:00

When sysctl_record_panic_msg is not set, the panic will
not be reported to Hyper-V via hyperv_report_panic_msg().
So the crash should be reported via hyperv_report_panic().

Fixes: 81b18bce48af ("Drivers: HV: Send one page worth of kmsg dump over Hyper-V during panic")
Reviewed-by: Michael Kelley 
Signed-off-by: Tianyu Lan 
Link: https://lore.kernel.org/r/20200406155331.2105-6-Tianyu.Lan@microsoft.com
Signed-off-by: Wei Liu

x86/Hyper-V: Trigger crash enlightenment only once during system crash.

2020-04-11T16:18:22+00:00

When a guest VM panics, Hyper-V should be notified only once via the
crash synthetic MSRs.  Current Linux code might write these crash MSRs
twice during a system panic:
1) hyperv_panic/die_event() calling hyperv_report_panic()
2) hv_kmsg_dump() calling hyperv_report_panic_msg()

Fix this by not calling hyperv_report_panic() if a kmsg dump has been
successfully registered.  The notification will happen later via
hyperv_report_panic_msg().

Fixes: 7ed4325a44ea ("Drivers: hv: vmbus: Make panic reporting to be more useful")
Reviewed-by: Michael Kelley 
Signed-off-by: Tianyu Lan 
Link: https://lore.kernel.org/r/20200406155331.2105-4-Tianyu.Lan@microsoft.com
Signed-off-by: Wei Liu

x86/Hyper-V: Free hv_panic_page when fail to register kmsg dump

2020-04-10T14:29:00+00:00

If kmsg_dump_register() fails, hv_panic_page will not be used
anywhere.  So free and reset it.

Fixes: 81b18bce48af ("Drivers: HV: Send one page worth of kmsg dump over Hyper-V during panic")
Reviewed-by: Michael Kelley 
Signed-off-by: Tianyu Lan 
Link: https://lore.kernel.org/r/20200406155331.2105-3-Tianyu.Lan@microsoft.com
Signed-off-by: Wei Liu