On Sat, Apr 23, 2022 at 08:51:16AM +0200, Greg Kroah-Hartman wrote: > On Fri, Apr 22, 2022 at 02:19:48PM +0000, Sebastian Ene wrote: > > This adds a mechanism to detect stalls on the guest vCPUS by creating a > > per CPU hrtimer which periodically 'pets' the host backend driver. > > > > This device driver acts as a soft lockup detector by relying on the host > > backend driver to measure the elapesed time between subsequent 'pet' events. > > If the elapsed time doesn't match an expected value, the backend driver > > decides that the guest vCPU is locked and resets the guest. The host > > backend driver takes into account the time that the guest is not > > running. The communication with the backend driver is done through MMIO > > and the register layout of the virtual watchdog is described as part of > > the backend driver changes. > > > > The host backend driver is implemented as part of: > > https://chromium-review.googlesource.com/c/chromiumos/platform/crosvm/+/3548817 > > > > Changelog v2: > > - move the driver to misc as this does not cope with watchdog core > > subsystem Hello Greg, > > Wait, why does it not cope with it? That's not documented anywhere in > your patch that adds the driver. In fact, most of the text here needs > to be in the changelog for the driver submission, not thrown away in the > 00/XX email that will never end up in the kernel tree. > > thanks, > > greg k-h
