linux-toradex.git/drivers/hv, branch v5.11

x86/hyperv: Fix kexec panic/hang issues

2021-01-05T17:52:04+00:00

Currently the kexec kernel can panic or hang due to 2 causes:

1) hv_cpu_die() is not called upon kexec, so the hypervisor corrupts the
old VP Assist Pages when the kexec kernel runs. The same issue is fixed
for hibernation in commit 421f090c819d ("x86/hyperv: Suspend/resume the
VP assist page for hibernation"). Now fix it for kexec.

2) hyperv_cleanup() is called too early. In the kexec path, the other CPUs
are stopped in hv_machine_shutdown() -> native_machine_shutdown(), so
between hv_kexec_handler() and native_machine_shutdown(), the other CPUs
can still try to access the hypercall page and cause panic. The workaround
"hv_hypercall_pg = NULL;" in hyperv_cleanup() is unreliabe. Move
hyperv_cleanup() to a better place.

Signed-off-by: Dexuan Cui 
Reviewed-by: Michael Kelley 
Link: https://lore.kernel.org/r/20201222065541.24312-1-decui@microsoft.com
Signed-off-by: Wei Liu

Merge tag 'hyperv-next-signed-20201214' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux

2020-12-16T19:49:46+00:00

Pull Hyper-V updates from Wei Liu:

 - harden VMBus (Andres Beltran)

 - clean up VMBus driver (Matheus Castello)

 - fix hv_balloon reporting (Vitaly Kuznetsov)

 - fix a potential OOB issue (Andrea Parri)

 - remove an obsolete TODO item (Stefan Eschenbacher)

* tag 'hyperv-next-signed-20201214' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux:
  hv_balloon: do adjust_managed_page_count() when ballooning/un-ballooning
  hv_balloon: simplify math in alloc_balloon_pages()
  drivers/hv: remove obsolete TODO and fix misleading typo in comment
  drivers: hv: vmbus: Fix checkpatch SPLIT_STRING
  hv_netvsc: Validate number of allocated sub-channels
  drivers: hv: vmbus: Fix call msleep using < 20ms
  drivers: hv: vmbus: Fix checkpatch LINE_SPACING
  drivers: hv: vmbus: Replace symbolic permissions by octal permissions
  drivers: hv: Fix hyperv_record_panic_msg path on comment
  hv_netvsc: Use vmbus_requestor to generate transaction IDs for VMBus hardening
  scsi: storvsc: Use vmbus_requestor to generate transaction IDs for VMBus hardening
  Drivers: hv: vmbus: Add vmbus_requestor data structure for VMBus hardening

hv_balloon: do adjust_managed_page_count() when ballooning/un-ballooning

2020-12-13T15:06:10+00:00

Unlike virtio_balloon/virtio_mem/xen balloon drivers, Hyper-V balloon driver
does not adjust managed pages count when ballooning/un-ballooning and this leads
to incorrect stats being reported, e.g. unexpected 'free' output.

Note, the calculation in post_status() seems to remain correct: ballooned out
pages are never 'available' and we manually add dm->num_pages_ballooned to
'commited'.

Suggested-by: David Hildenbrand 
Signed-off-by: Vitaly Kuznetsov 
Reviewed-by: David Hildenbrand 
Link: https://lore.kernel.org/r/20201202161245.2406143-3-vkuznets@redhat.com
Signed-off-by: Wei Liu

hv_balloon: simplify math in alloc_balloon_pages()

2020-12-13T15:06:05+00:00

'alloc_unit' in alloc_balloon_pages() is either '512' for 2M allocations or
'1' for 4k allocations. So

1 << get_order(alloc_unit << PAGE_SHIFT)

equals to 'alloc_unit' and the for loop basically sets all them offline.
Simplify the math to improve the readability.

Signed-off-by: Vitaly Kuznetsov 
Reviewed-by: David Hildenbrand 
Link: https://lore.kernel.org/r/20201202161245.2406143-2-vkuznets@redhat.com
Signed-off-by: Wei Liu

drivers/hv: remove obsolete TODO and fix misleading typo in comment

2020-12-07T11:24:08+00:00

Removes an obsolete TODO in the VMBus module and fixes a misleading typo
in the comment for the macro MAX_NUM_CHANNELS, where two digits have been
twisted.

Signed-off-by: Stefan Eschenbacher 
Co-developed-by: Max Stolze 
Signed-off-by: Max Stolze 
Link: https://lore.kernel.org/r/20201206104850.24843-1-stefan.eschenbacher@fau.de
Signed-off-by: Wei Liu

drivers: hv: vmbus: Fix checkpatch SPLIT_STRING

2020-12-02T11:54:19+00:00

Checkpatch emits WARNING: quoted string split across lines.
To keep the code clean and with the 80 column length indentation the
check and registration code for kmsg_dump_register has been transferred
to a new function hv_kmsg_dump_register.

Signed-off-by: Matheus Castello 
Reviewed-by: Michael Kelley 
Link: https://lore.kernel.org/r/20201125032926.17002-1-matheus@castello.eng.br
Signed-off-by: Wei Liu

drivers: hv: vmbus: Fix call msleep using < 20ms

2020-11-17T10:56:48+00:00

Fixed checkpatch warning: MSLEEP: msleep < 20ms can sleep for up to
20ms; see Documentation/timers/timers-howto.rst

Signed-off-by: Matheus Castello 
Reviewed-by: Michael Kelley 
Link: https://lore.kernel.org/r/20201115195734.8338-7-matheus@castello.eng.br
Signed-off-by: Wei Liu

drivers: hv: vmbus: Fix checkpatch LINE_SPACING

2020-11-17T10:56:44+00:00

Fixed checkpatch warning: Missing a blank line after declarations
checkpatch(LINE_SPACING)

Signed-off-by: Matheus Castello 
Reviewed-by: Michael Kelley 
Link: https://lore.kernel.org/r/20201115195734.8338-4-matheus@castello.eng.br
Signed-off-by: Wei Liu

drivers: hv: vmbus: Replace symbolic permissions by octal permissions

2020-11-17T10:56:39+00:00

This fixed the below checkpatch issue:
WARNING: Symbolic permissions 'S_IRUGO' are not preferred.
Consider using octal permissions '0444'.

Signed-off-by: Matheus Castello 
Reviewed-by: Michael Kelley 
Link: https://lore.kernel.org/r/20201115195734.8338-3-matheus@castello.eng.br
Signed-off-by: Wei Liu

drivers: hv: Fix hyperv_record_panic_msg path on comment

2020-11-17T10:56:24+00:00

Fix the kernel parameter path in the comment, in the documentation the
parameter is correct but if someone who is studying the code and see
this first can get confused and try to access the wrong path/parameter

Signed-off-by: Matheus Castello 
Reviewed-by: Michael Kelley 
Link: https://lore.kernel.org/r/20201115195734.8338-2-matheus@castello.eng.br
Signed-off-by: Wei Liu