| Message ID | 155146875704.147873.10563808578795890265.stgit@bahia.lan |
|---|---|
| State | New |
| Headers | show |
| Series | spapr: Fix CPU unplug tests | expand |
Quoting Greg Kurz (2019-03-01 13:32:37) > The RTAS event hotplug code for machine types 2.8 and newer depends on > the CAS negotiated ov5 in order to work properly. However, there's no > CAS when running under qtest. There has been a tentative to trick the > code by faking the OV5_HP_EVT bit, but it turned out to break other > assumptions in the code and the change got reverted. > > Go for a more general approach and simulate a CAS when running under > qtest. For simplicity, this pseudo CAS simple simulates the case where > the guest supports the same features as the machine. It is done at > reset time, just before we reset the DRCs, which could potentially > exercise the unplug code. > > This allows to test unplug on spapr with both older and newer machine > types. > > Suggested-by: Michael Roth <mdroth@linux.vnet.ibm.com> > Signed-off-by: Greg Kurz <groug@kaod.org> Tested-by: Michael Roth <mdroth@linux.vnet.ibm.com> Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com> Thanks for sending this! Just now realizing we should probably apply the revert after this patch however, since the commit we're reverting fixes a `make check` test that is run by default, whereas this patch fixes one that only gets run if we run the tests with -m=slow specified. Maybe David can do that on his end? > --- > hw/ppc/spapr.c | 11 +++++++++++ > 1 file changed, 11 insertions(+) > > diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c > index b6a571b6f184..6da64ef7ee2b 100644 > --- a/hw/ppc/spapr.c > +++ b/hw/ppc/spapr.c > @@ -29,6 +29,7 @@ > #include "qapi/visitor.h" > #include "sysemu/sysemu.h" > #include "sysemu/numa.h" > +#include "sysemu/qtest.h" > #include "hw/hw.h" > #include "qemu/log.h" > #include "hw/fw-path-provider.h" > @@ -1711,6 +1712,16 @@ static void spapr_machine_reset(void) > */ > spapr_irq_reset(spapr, &error_fatal); > > + /* > + * There is no CAS under qtest. Simulate one to please the code that > + * depends on spapr->ov5_cas. This is especially needed to test device > + * unplug, so we do that before resetting the DRCs. > + */ > + if (qtest_enabled()) { > + spapr_ovec_cleanup(spapr->ov5_cas); > + spapr->ov5_cas = spapr_ovec_clone(spapr->ov5); > + } > + > /* DRC reset may cause a device to be unplugged. This will cause troubles > * if this device is used by another device (eg, a running vhost backend > * will crash QEMU if the DIMM holding the vring goes away). To avoid such >
On Fri, Mar 01, 2019 at 04:33:38PM -0600, Michael Roth wrote: > Quoting Greg Kurz (2019-03-01 13:32:37) > > The RTAS event hotplug code for machine types 2.8 and newer depends on > > the CAS negotiated ov5 in order to work properly. However, there's no > > CAS when running under qtest. There has been a tentative to trick the > > code by faking the OV5_HP_EVT bit, but it turned out to break other > > assumptions in the code and the change got reverted. > > > > Go for a more general approach and simulate a CAS when running under > > qtest. For simplicity, this pseudo CAS simple simulates the case where > > the guest supports the same features as the machine. It is done at > > reset time, just before we reset the DRCs, which could potentially > > exercise the unplug code. > > > > This allows to test unplug on spapr with both older and newer machine > > types. > > > > Suggested-by: Michael Roth <mdroth@linux.vnet.ibm.com> > > Signed-off-by: Greg Kurz <groug@kaod.org> > > Tested-by: Michael Roth <mdroth@linux.vnet.ibm.com> > Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com> > > Thanks for sending this! > > Just now realizing we should probably apply the revert after this patch > however, since the commit we're reverting fixes a `make check` test that > is run by default, whereas this patch fixes one that only gets run if we > run the tests with -m=slow specified. > > Maybe David can do that on his end? Applied in reverse order as suggested to ppc-for-4.0. Thanks. > > > --- > > hw/ppc/spapr.c | 11 +++++++++++ > > 1 file changed, 11 insertions(+) > > > > diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c > > index b6a571b6f184..6da64ef7ee2b 100644 > > --- a/hw/ppc/spapr.c > > +++ b/hw/ppc/spapr.c > > @@ -29,6 +29,7 @@ > > #include "qapi/visitor.h" > > #include "sysemu/sysemu.h" > > #include "sysemu/numa.h" > > +#include "sysemu/qtest.h" > > #include "hw/hw.h" > > #include "qemu/log.h" > > #include "hw/fw-path-provider.h" > > @@ -1711,6 +1712,16 @@ static void spapr_machine_reset(void) > > */ > > spapr_irq_reset(spapr, &error_fatal); > > > > + /* > > + * There is no CAS under qtest. Simulate one to please the code that > > + * depends on spapr->ov5_cas. This is especially needed to test device > > + * unplug, so we do that before resetting the DRCs. > > + */ > > + if (qtest_enabled()) { > > + spapr_ovec_cleanup(spapr->ov5_cas); > > + spapr->ov5_cas = spapr_ovec_clone(spapr->ov5); > > + } > > + > > /* DRC reset may cause a device to be unplugged. This will cause troubles > > * if this device is used by another device (eg, a running vhost backend > > * will crash QEMU if the DIMM holding the vring goes away). To avoid such > > >
diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c index b6a571b6f184..6da64ef7ee2b 100644 --- a/hw/ppc/spapr.c +++ b/hw/ppc/spapr.c @@ -29,6 +29,7 @@ #include "qapi/visitor.h" #include "sysemu/sysemu.h" #include "sysemu/numa.h" +#include "sysemu/qtest.h" #include "hw/hw.h" #include "qemu/log.h" #include "hw/fw-path-provider.h" @@ -1711,6 +1712,16 @@ static void spapr_machine_reset(void) */ spapr_irq_reset(spapr, &error_fatal); + /* + * There is no CAS under qtest. Simulate one to please the code that + * depends on spapr->ov5_cas. This is especially needed to test device + * unplug, so we do that before resetting the DRCs. + */ + if (qtest_enabled()) { + spapr_ovec_cleanup(spapr->ov5_cas); + spapr->ov5_cas = spapr_ovec_clone(spapr->ov5); + } + /* DRC reset may cause a device to be unplugged. This will cause troubles * if this device is used by another device (eg, a running vhost backend * will crash QEMU if the DIMM holding the vring goes away). To avoid such
The RTAS event hotplug code for machine types 2.8 and newer depends on the CAS negotiated ov5 in order to work properly. However, there's no CAS when running under qtest. There has been a tentative to trick the code by faking the OV5_HP_EVT bit, but it turned out to break other assumptions in the code and the change got reverted. Go for a more general approach and simulate a CAS when running under qtest. For simplicity, this pseudo CAS simple simulates the case where the guest supports the same features as the machine. It is done at reset time, just before we reset the DRCs, which could potentially exercise the unplug code. This allows to test unplug on spapr with both older and newer machine types. Suggested-by: Michael Roth <mdroth@linux.vnet.ibm.com> Signed-off-by: Greg Kurz <groug@kaod.org> --- hw/ppc/spapr.c | 11 +++++++++++ 1 file changed, 11 insertions(+)