On Tue, Sep 24, 2024 at 03:26:14AM +0000, Srivatsa S. Bhat wrote: > Hi Vennela, > > [+linux-pm, Rafael, Pavel, Len] > > Let's CC the linux-pm mailing list for discussions related to power > management features (such as suspend/resume and hibernation). > > On Thu, Sep 12, 2024 at 02:27:47PM -0700, Erni Sri Satya Vennela wrote: > > It has been reported that Hyper-V VM users can unintentionally abort > > hibernation by mouse or keyboard movements. To address this issue, > > we have decided to remove the wakeup events for the Hyper-V keyboard > > and mouse driver. > > >From the description of the problem, it doesn't occur to me that this > is specific to Hyper-V. I was wondering if VMs on other hypervisor > platforms wouldn't face the same issue? I'd like to recommend > exploring how this problem has been solved for other platforms, so > that we can reuse the same approach here. (If it turns out that > removing keyboard and mouse wakeup events is the way to go, then > great; otherwise, we can learn and apply the recommended solution). > This is how the keyboard and mouse devices can be disabled manually and is the proper way to address this issue. >echo disabled > /sys/bus/vmbus/drivers/hid_hyperv/$HV_MOUSE/power/wakeup >echo disabled > >/sys/bus/vmbus/drivers/hyperv_keyboard/$HV_KEYBOARD/power/wakeup >systemctl hibernate But based on customer feedback we are totally eliminating them as wakeup events. Initially, they were registered as wakeup events to wakeup from Suspend-to-Idle state. Since there is no real user of this operation, we are disabling them to ensure they do not interfere with hibernation process. > > However, this change introduces another problem: > > Suspend-to-Idle brings the system down with no method to wake it back up. > > > > Given that there are no real users of Suspend-to-Idle in Hyper-V, > > we have decided to disable this feature for VMBus. This results in: > > > > $echo freeze > /sys/power/state > > > bash: echo: write error: Operation not supported > > > > The keyboard and mouse were previously registered as wakeup sources to > > interrupt the freeze operation in a VM. Since the freeze operation itself > > is no longer supported, we are disabling them as wakeup events. > > > > This patchset ensures that the system remains stable and prevents > > unintended interruptions during hibernation. > > > > Erni Sri Satya Vennela (3): > > Drivers: hv: vmbus: Disable Suspend-to-Idle for VMBus > > Revert "Input: hyperv-keyboard - register as a wakeup source" > > Revert "HID: hyperv: register as a wakeup source" > > > > drivers/hid/hid-hyperv.c | 6 ------ > > drivers/hv/vmbus_drv.c | 15 ++++++++++++++- > > drivers/input/serio/hyperv-keyboard.c | 12 ------------ > > 3 files changed, 14 insertions(+), 19 deletions(-) > > > > -- > > 2.34.1 > > > > > > Regards, > Srivatsa > Microsoft Linux Systems Group
