On Sun, 8 Dec 2019 00:14:00 +1100 Gavin Shan <gs...@redhat.com> wrote:
> On 12/7/19 3:50 AM, Greg Kurz wrote: > > On Fri, 6 Dec 2019 17:36:42 +1100 > > Gavin Shan <gs...@redhat.com> wrote: > > > >> object_dynamic_cast() should return machine (or GPIO) state instad of NMI > >> state in do_nmi(). So it's wrong to convert it to NMI state > >> unconditionally. > >> > > > > object_dynamic_cast() returns either its first argument if it can be cast > > to the given typename or NULL. Since the x86, ccw and spapr machines and > > the PowerMac GPIO implement the NMI interface, nothing is wrong here. > > > > The do_nmi() function is called for all objects in the QOM tree and simply > > filters out the ones that don't implement the NMI interface. > > > > I do agree that this isn't super obvious though. It would be clearer to > > do the filtering in the foreach() function. Something like: > > > > https://patchwork.ozlabs.org/patch/1182232/ > > > > Greg, Thanks for the review and comments. I think we're talking about > different issues. I do agree it's worthy to simplify the code with the > object_child_foreach_type(), but later. > > When we have below parameters to qemu, object_dynamic_cast(o, TYPE_NMI) > returns object of "pc-q35-4.2-machine", which is passed to the subquent > NMIClass::nmi_monitor_handler(). However, the function expects a NMIState > from its prototype as below. This patch changes the prototype to fill the > gap. > > void (*nmi_monitor_handler)(NMIState *n, int cpu_index, Error **errp); > Hmm... the "pc-q35-4.2-machine" type inherits from the TYPE_PC_MACHINE, which in turns inherits from TYPE_X86_MACHINE, which implements the TYPE_NMI interface. It thus seems okay to pass this object to x86_nmi(). What are you trying to fix here ? > Changed to: > > void (*nmi_monitor_handler)(Object *parent, int cpu_index, Error **errp); > > ~/sandbox/src/qemu/qemu.main.x86/x86_64-softmmu/qemu-system-x86_64 > \ > --enable-kvm -machine type=q35,accel=kvm,kernel-irqchip=on -cpu host -smp > 2 -m 1G \ > -monitor none -serial mon:stdio -nographic -s > \ > -bios ~/sandbox/src/firmware/seabios/out/bios.bin > \ > -kernel ~/sandbox/src/linux/linux.main.x86/arch/x86/boot/bzImage > \ > -initrd ~/sandbox/src/util/buildroot/output/images/rootfs.cpio.xz > \ > -append "earlyprintk=ttyS0 console=ttyS0 debug" > \ > -device virtio-net-pci,netdev=unet,mac=52:54:00:f1:26:a6 > \ > -netdev user,id=unet,hostfwd=tcp::50959-:22 > \ > -drive file=~/sandbox/images/vm.img,if=none,format=raw,id=nvme0 > \ > -device nvme,drive=nvme0,serial=foo > \ > -drive file=~/sandbox/images/vm1.img,if=none,format=raw,id=nvme1 > \ > -device nvme,drive=nvme1,serial=foo1 > > >> This changes the prototype of NMIClass::nmi_monitor_handler() to accept > >> the parent object of NMI state instead of itself. With this, he parent > >> object > >> is passed to the function, to avoid potential data corruption. > >> > >> Signed-off-by: Gavin Shan <gs...@redhat.com> > >> --- > >> hw/core/nmi.c | 8 ++++---- > >> hw/i386/x86.c | 2 +- > >> hw/misc/macio/gpio.c | 6 +++--- > >> hw/ppc/spapr.c | 2 +- > >> hw/s390x/s390-virtio-ccw.c | 2 +- > >> include/hw/nmi.h | 2 +- > >> 6 files changed, 11 insertions(+), 11 deletions(-) > >> > >> diff --git a/hw/core/nmi.c b/hw/core/nmi.c > >> index 481c4b3c7e..554708d0db 100644 > >> --- a/hw/core/nmi.c > >> +++ b/hw/core/nmi.c > >> @@ -37,13 +37,13 @@ static void nmi_children(Object *o, struct do_nmi_s > >> *ns); > >> static int do_nmi(Object *o, void *opaque) > >> { > >> struct do_nmi_s *ns = opaque; > >> - NMIState *n = (NMIState *) object_dynamic_cast(o, TYPE_NMI); > >> + Object *parent = object_dynamic_cast(o, TYPE_NMI); > >> > >> - if (n) { > >> - NMIClass *nc = NMI_GET_CLASS(n); > >> + if (parent) { > >> + NMIClass *nc = NMI_GET_CLASS(parent); > >> > >> ns->handled = true; > >> - nc->nmi_monitor_handler(n, ns->cpu_index, &ns->err); > >> + nc->nmi_monitor_handler(parent, ns->cpu_index, &ns->err); > >> if (ns->err) { > >> return -1; > >> } > >> diff --git a/hw/i386/x86.c b/hw/i386/x86.c > >> index 394edc2f72..b98204f104 100644 > >> --- a/hw/i386/x86.c > >> +++ b/hw/i386/x86.c > >> @@ -190,7 +190,7 @@ const CPUArchIdList > >> *x86_possible_cpu_arch_ids(MachineState *ms) > >> return ms->possible_cpus; > >> } > >> > >> -static void x86_nmi(NMIState *n, int cpu_index, Error **errp) > >> +static void x86_nmi(Object *parent, int cpu_index, Error **errp) > >> { > >> /* cpu index isn't used */ > >> CPUState *cs; > >> diff --git a/hw/misc/macio/gpio.c b/hw/misc/macio/gpio.c > >> index 6cca6b27d6..6b4dfcc188 100644 > >> --- a/hw/misc/macio/gpio.c > >> +++ b/hw/misc/macio/gpio.c > >> @@ -196,10 +196,10 @@ static void macio_gpio_reset(DeviceState *dev) > >> macio_set_gpio(s, 1, true); > >> } > >> > >> -static void macio_gpio_nmi(NMIState *n, int cpu_index, Error **errp) > >> +static void macio_gpio_nmi(Object *parent, int cpu_index, Error **errp) > >> { > >> - macio_set_gpio(MACIO_GPIO(n), 9, true); > >> - macio_set_gpio(MACIO_GPIO(n), 9, false); > >> + macio_set_gpio(MACIO_GPIO(parent), 9, true); > >> + macio_set_gpio(MACIO_GPIO(parent), 9, false); > >> } > >> > >> static void macio_gpio_class_init(ObjectClass *oc, void *data) > >> diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c > >> index e076f6023c..3b92e4013d 100644 > >> --- a/hw/ppc/spapr.c > >> +++ b/hw/ppc/spapr.c > >> @@ -3377,7 +3377,7 @@ void spapr_do_system_reset_on_cpu(CPUState *cs, > >> run_on_cpu_data arg) > >> ppc_cpu_do_system_reset(cs); > >> } > >> > >> -static void spapr_nmi(NMIState *n, int cpu_index, Error **errp) > >> +static void spapr_nmi(Object *parent, int cpu_index, Error **errp) > >> { > >> CPUState *cs; > >> > >> diff --git a/hw/s390x/s390-virtio-ccw.c b/hw/s390x/s390-virtio-ccw.c > >> index d3edeef0ad..a49952a8b9 100644 > >> --- a/hw/s390x/s390-virtio-ccw.c > >> +++ b/hw/s390x/s390-virtio-ccw.c > >> @@ -431,7 +431,7 @@ static void s390_hot_add_cpu(MachineState *machine, > >> s390x_new_cpu(object_class_get_name(oc), id, errp); > >> } > >> > >> -static void s390_nmi(NMIState *n, int cpu_index, Error **errp) > >> +static void s390_nmi(Object *parent, int cpu_index, Error **errp) > >> { > >> CPUState *cs = qemu_get_cpu(cpu_index); > >> > >> diff --git a/include/hw/nmi.h b/include/hw/nmi.h > >> index a1e128724e..75afa67790 100644 > >> --- a/include/hw/nmi.h > >> +++ b/include/hw/nmi.h > >> @@ -38,7 +38,7 @@ typedef struct NMIState NMIState; > >> typedef struct NMIClass { > >> InterfaceClass parent_class; > >> > >> - void (*nmi_monitor_handler)(NMIState *n, int cpu_index, Error **errp); > >> + void (*nmi_monitor_handler)(Object *parent, int cpu_index, Error > >> **errp); > >> } NMIClass; > >> > >> void nmi_monitor_handle(int cpu_index, Error **errp); > > > > Regards, > Gavin >
