Often when a guest is stopped from the qemu console, it will report spurious soft lockup warnings on resume. There are kernel patches being discussed that will give the host the ability to tell the guest that it is being stopped and should ignore the soft lockup warning that generates. This patch uses the qemu Notifier system to tell the guest it is about to be stopped.
Signed-off-by: Eric B Munson <[email protected]> Cc: Avi Kivity <[email protected]> Cc: Marcelo Tosatti <[email protected]> Cc: Jan Kiszka <[email protected]> Cc: [email protected] Cc: [email protected] Cc: [email protected] --- Changes from V4: Test if the guest paused capability is available before use Changes from V3: Collapse new state change notification function into existsing function. Correct whitespace issues Change ioctl name to KVMCLOCK_GUEST_PAUSED Use for loop to iterate vpcu's Changes from V2: Move ioctl into hw/kvmclock.c so as other arches can use it as it is implemented Changes from V1: Remove unnecessary encapsulating function hw/kvmclock.c | 20 ++++++++++++++++++++ 1 files changed, 20 insertions(+), 0 deletions(-) diff --git a/hw/kvmclock.c b/hw/kvmclock.c index 5388bc4..d071d61 100644 --- a/hw/kvmclock.c +++ b/hw/kvmclock.c @@ -16,6 +16,7 @@ #include "sysbus.h" #include "kvm.h" #include "kvmclock.h" +#include "cpu-all.h" #include <linux/kvm.h> #include <linux/kvm_para.h> @@ -62,10 +63,29 @@ static int kvmclock_post_load(void *opaque, int version_id) static void kvmclock_vm_state_change(void *opaque, int running, RunState state) { + int ret; + CPUState *penv = first_cpu; KVMClockState *s = opaque; + int cap_guest_paused = kvm_check_extension(kvm_state, KVM_CAP_GUEST_PAUSED); if (running) { s->clock_valid = false; + + if (!cap_guest_paused) { + return; + } + + for (penv = first_cpu; penv != NULL; penv = penv->next_cpu) { + ret = kvm_vcpu_ioctl(penv, KVMCLOCK_GUEST_PAUSED, 0); + if (ret) { + if (ret != -EINVAL) { + fprintf(stderr, + "kvmclock_vm_state_change: %s\n", + strerror(-ret)); + } + return; + } + } } } -- 1.7.5.4 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
