On Tue, Apr 23, 2024 at 09:13:08AM +0000, Masato Imai wrote: > When the KVM acceleration parameter is not set, executing calc_dirty_rate > with the -r or -b option results in a segmentation fault due to accessing > a null kvm_state pointer in the kvm_dirty_ring_enabled function. > This commit adds a check for kvm_enabled to prevent segmentation faults. > > Signed-off-by: Masato Imai <m...@sfc.wide.ad.jp> > --- > migration/dirtyrate.c | 7 +++++++ > 1 file changed, 7 insertions(+) > > diff --git a/migration/dirtyrate.c b/migration/dirtyrate.c > index 1d2e85746f..2a7df52519 100644 > --- a/migration/dirtyrate.c > +++ b/migration/dirtyrate.c > @@ -799,6 +799,13 @@ void qmp_calc_dirty_rate(int64_t calc_time, > * dirty ring mode only works when kvm dirty ring is enabled. > * on the contrary, dirty bitmap mode is not. > */ > + if (!kvm_enabled() && > + (mode == DIRTY_RATE_MEASURE_MODE_DIRTY_RING || > + mode == DIRTY_RATE_MEASURE_MODE_DIRTY_BITMAP)) { > + error_setg(errp, "mode %s requires kvm to be enabled.", > + DirtyRateMeasureMode_str(mode)); > + return; > + }
Logically dirty bitmap should work with tcg. So the other option is to let kvm_dirty_ring_enabled() check kvm_state too and return false if kvm_state==NULL? > if (((mode == DIRTY_RATE_MEASURE_MODE_DIRTY_RING) && > !kvm_dirty_ring_enabled()) || > ((mode == DIRTY_RATE_MEASURE_MODE_DIRTY_BITMAP) && > -- > 2.34.1 > -- Peter Xu