Michael Kelley <mikelley@xxxxxxxxxxxxx> writes: > The crash handler calls hv_synic_cleanup() to shutdown the > Hyper-V synthetic interrupt controller. But if the CPU > that calls hv_synic_cleanup() has a VMbus channel interrupt > assigned to it (which is likely the case in smaller VM sizes), > hv_synic_cleanup() returns an error and the synthetic > interrupt controller isn't shutdown. While the lack of > being shutdown hasn't caused a known problem, it still > should be fixed for highest reliability. > > So directly call hv_synic_disable_regs() instead of > hv_synic_cleanup(), which ensures that the synic is always > shutdown. Generally, when performing kdump doing as little work as possible is always preferred and hv_synic_cleanup() does too much: taking mutex, walking through channel list,... Also, hv_synic_cleanup() was calling hv_stimer_cleanup() and we have a second redundant invocation in hv_crash_handler(). > > Signed-off-by: Michael Kelley <mikelley@xxxxxxxxxxxxx> > --- > drivers/hv/vmbus_drv.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c > index 664a415..665920d 100644 > --- a/drivers/hv/vmbus_drv.c > +++ b/drivers/hv/vmbus_drv.c > @@ -2305,7 +2305,7 @@ static void hv_crash_handler(struct pt_regs *regs) > vmbus_connection.conn_state = DISCONNECTED; > cpu = smp_processor_id(); > hv_stimer_cleanup(cpu); > - hv_synic_cleanup(cpu); > + hv_synic_disable_regs(cpu); > hyperv_cleanup(); > }; Reviewed-by: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx> -- Vitaly
