The hv_sleep_notifiers_register() and hv_machine_power_off() functions are
only called and declared on x86, but cause a warning on arm64:
drivers/hv/mshv_common.c:210:6: error: no previous prototype for 'hv_sleep_notifiers_register' [-Werror=missing-prototypes]
210 | void hv_sleep_notifiers_register(void)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/hv/mshv_common.c:224:6: error: no previous prototype for 'hv_machine_power_off' [-Werror=missing-prototypes]
224 | void hv_machine_power_off(void)
| ^~~~~~~~~~~~~~~~~~~~
Hide both inside of an #ifdef block.
Fixes: f0be2600ac ("mshv: Use reboot notifier to configure sleep state")
Fixes: 615a6e7d83 ("mshv: Cleanly shutdown root partition with MSHV")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Root partitions running on MSHV currently attempt ACPI power-off, which
MSHV intercepts and triggers a Machine Check Exception (MCE), leading
to a kernel panic.
Root partitions panic with a trace similar to:
[ 81.306348] reboot: Power down
[ 81.314709] mce: [Hardware Error]: CPU 0: Machine Check Exception: 4 Bank 0: b2000000c0060001
[ 81.314711] mce: [Hardware Error]: TSC 3b8cb60a66 PPIN 11d98332458e4ea9
[ 81.314713] mce: [Hardware Error]: PROCESSOR 0:606a6 TIME 1759339405 SOCKET 0 APIC 0 microcode ffffffff
[ 81.314715] mce: [Hardware Error]: Run the above through 'mcelog --ascii'
[ 81.314716] mce: [Hardware Error]: Machine check: Processor context corrupt
[ 81.314717] Kernel panic - not syncing: Fatal machine check
To avoid this, configure the sleep state in the hypervisor and invoke
the HVCALL_ENTER_SLEEP_STATE hypercall as the final step in the shutdown
sequence. This ensures a clean and safe shutdown of the root partition.
Signed-off-by: Praveen K Paladugu <prapal@linux.microsoft.com>
Co-developed-by: Anatol Belski <anbelski@linux.microsoft.com>
Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
Reviewed-by: Easwar Hariharan <easwar.hariharan@linux.microsoft.com>
Acked-by: Stanislav Kinsburskii <skinsburskii@linux.microsoft.com>
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Configure sleep state information from ACPI in MSHV hypervisor using
a reboot notifier. This data allows the hypervisor to correctly power
off the host during shutdown.
Signed-off-by: Praveen K Paladugu <prapal@linux.microsoft.com>
Co-developed-by: Anatol Belski <anbelski@linux.microsoft.com>
Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
Reviewed-by: Easwar Hariharan <easwar.hariharan@linux.microsoft.com>
Reviewed-by: Stansialv Kinsburskii <skinsburskii@linux.miscrosoft.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Nuno Das Neves <nunodasneves@linux.microsoft.com>
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Use the kernel's common "entry virt" APIs to handle pending work prior to
(re)entering guest mode, now that the virt APIs don't have a superfluous
dependency on KVM.
No functional change intended.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Tested-by: Nuno Das Neves <nunodasneves@linux.microsoft.com>
Reviewed-by: Nuno Das Neves <nunodasneves@linux.microsoft.com>
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Check for NEED_RESCHED_LAZY, not just NEED_RESCHED, prior to transferring
control to a guest. Failure to check for lazy resched can unnecessarily
delay rescheduling until the next tick when using a lazy preemption model.
Note, ideally both the checking and processing of TIF bits would be handled
in common code, to avoid having to keep three separate paths synchronized,
but defer such cleanups to the future to keep the fix as standalone as
possible.
Cc: Nuno Das Neves <nunodasneves@linux.microsoft.com>
Cc: Mukesh R <mrathor@linux.microsoft.com>
Fixes: 621191d709 ("Drivers: hv: Introduce mshv_root module to expose /dev/mshv to VMMs")
Signed-off-by: Sean Christopherson <seanjc@google.com>
Tested-by: Nuno Das Neves <nunodasneves@linux.microsoft.com>
Reviewed-by: Nuno Das Neves <nunodasneves@linux.microsoft.com>
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Fix below warning in Hyper-V drivers that comes when kernel is compiled
with W=1 option. Include export.h in driver files to fix it.
* warning: EXPORT_SYMBOL() is used, but #include <linux/export.h>
is missing
Signed-off-by: Naman Jain <namjain@linux.microsoft.com>
Reviewed-by: Nuno Das Neves <nunodasneves@linux.microsoft.com>
Reviewed-by: Saurabh Sengar <ssengar@linux.microsoft.com>
Link: https://lore.kernel.org/r/20250611100459.92900-2-namjain@linux.microsoft.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Message-ID: <20250611100459.92900-2-namjain@linux.microsoft.com>
Provide a set of IOCTLs for creating and managing child partitions when
running as root partition on Hyper-V. The new driver is enabled via
CONFIG_MSHV_ROOT.
A brief overview of the interface:
MSHV_CREATE_PARTITION is the entry point, returning a file descriptor
representing a child partition. IOCTLs on this fd can be used to map
memory, create VPs, etc.
Creating a VP returns another file descriptor representing that VP which
in turn has another set of corresponding IOCTLs for running the VP,
getting/setting state, etc.
MSHV_ROOT_HVCALL is a generic "passthrough" hypercall IOCTL which can be
used for a number of partition or VP hypercalls. This is for hypercalls
that do not affect any state in the kernel driver, such as getting and
setting VP registers and partition properties, translating addresses,
etc. It is "passthrough" because the binary input and output for the
hypercall is only interpreted by the VMM - the kernel driver does
nothing but insert the VP and partition id where necessary (which are
always in the same place), and execute the hypercall.
Co-developed-by: Anirudh Rayabharam <anrayabh@linux.microsoft.com>
Signed-off-by: Anirudh Rayabharam <anrayabh@linux.microsoft.com>
Co-developed-by: Jinank Jain <jinankjain@microsoft.com>
Signed-off-by: Jinank Jain <jinankjain@microsoft.com>
Co-developed-by: Mukesh Rathor <mrathor@linux.microsoft.com>
Signed-off-by: Mukesh Rathor <mrathor@linux.microsoft.com>
Co-developed-by: Muminul Islam <muislam@microsoft.com>
Signed-off-by: Muminul Islam <muislam@microsoft.com>
Co-developed-by: Praveen K Paladugu <prapal@linux.microsoft.com>
Signed-off-by: Praveen K Paladugu <prapal@linux.microsoft.com>
Co-developed-by: Stanislav Kinsburskii <skinsburskii@linux.microsoft.com>
Signed-off-by: Stanislav Kinsburskii <skinsburskii@linux.microsoft.com>
Co-developed-by: Wei Liu <wei.liu@kernel.org>
Signed-off-by: Nuno Das Neves <nunodasneves@linux.microsoft.com>
Reviewed-by: Roman Kisel <romank@linux.microsoft.com>
Link: https://lore.kernel.org/r/1741980536-3865-11-git-send-email-nunodasneves@linux.microsoft.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Message-ID: <1741980536-3865-11-git-send-email-nunodasneves@linux.microsoft.com>