From 7d20e6815bf5ab678a55673224340b39218be510 Mon Sep 17 00:00:00 2001 From: Philippe Mathieu-Daudé Date: Tue, 23 Jun 2020 11:06:22 +0200 Subject: target/arm: Check supported KVM features globally (not per vCPU) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Since commit d70c996df23f, when enabling the PMU we get: $ qemu-system-aarch64 -cpu host,pmu=on -M virt,accel=kvm,gic-version=3 Segmentation fault (core dumped) Thread 1 "qemu-system-aar" received signal SIGSEGV, Segmentation fault. 0x0000aaaaaae356d0 in kvm_ioctl (s=0x0, type=44547) at accel/kvm/kvm-all.c:2588 2588 ret = ioctl(s->fd, type, arg); (gdb) bt #0 0x0000aaaaaae356d0 in kvm_ioctl (s=0x0, type=44547) at accel/kvm/kvm-all.c:2588 #1 0x0000aaaaaae31568 in kvm_check_extension (s=0x0, extension=126) at accel/kvm/kvm-all.c:916 #2 0x0000aaaaaafce254 in kvm_arm_pmu_supported (cpu=0xaaaaac214ab0) at target/arm/kvm.c:213 #3 0x0000aaaaaafc0f94 in arm_set_pmu (obj=0xaaaaac214ab0, value=true, errp=0xffffffffe438) at target/arm/cpu.c:1111 #4 0x0000aaaaab5533ac in property_set_bool (obj=0xaaaaac214ab0, v=0xaaaaac223a80, name=0xaaaaac11a970 "pmu", opaque=0xaaaaac222730, errp=0xffffffffe438) at qom/object.c:2170 #5 0x0000aaaaab5512f0 in object_property_set (obj=0xaaaaac214ab0, v=0xaaaaac223a80, name=0xaaaaac11a970 "pmu", errp=0xffffffffe438) at qom/object.c:1328 #6 0x0000aaaaab551e10 in object_property_parse (obj=0xaaaaac214ab0, string=0xaaaaac11b4c0 "on", name=0xaaaaac11a970 "pmu", errp=0xffffffffe438) at qom/object.c:1561 #7 0x0000aaaaab54ee8c in object_apply_global_props (obj=0xaaaaac214ab0, props=0xaaaaac018e20, errp=0xaaaaabd6fd88 ) at qom/object.c:407 #8 0x0000aaaaab1dd5a4 in qdev_prop_set_globals (dev=0xaaaaac214ab0) at hw/core/qdev-properties.c:1218 #9 0x0000aaaaab1d9fac in device_post_init (obj=0xaaaaac214ab0) at hw/core/qdev.c:1050 ... #15 0x0000aaaaab54f310 in object_initialize_with_type (obj=0xaaaaac214ab0, size=52208, type=0xaaaaabe237f0) at qom/object.c:512 #16 0x0000aaaaab54fa24 in object_new_with_type (type=0xaaaaabe237f0) at qom/object.c:687 #17 0x0000aaaaab54fa80 in object_new (typename=0xaaaaabe23970 "host-arm-cpu") at qom/object.c:702 #18 0x0000aaaaaaf04a74 in machvirt_init (machine=0xaaaaac0a8550) at hw/arm/virt.c:1770 #19 0x0000aaaaab1e8720 in machine_run_board_init (machine=0xaaaaac0a8550) at hw/core/machine.c:1138 #20 0x0000aaaaaaf95394 in qemu_init (argc=5, argv=0xffffffffea58, envp=0xffffffffea88) at softmmu/vl.c:4348 #21 0x0000aaaaaada3f74 in main (argc=, argv=, envp=) at softmmu/main.c:48 This is because in frame #2, cpu->kvm_state is still NULL (the vCPU is not yet realized). KVM has a hard requirement of all cores supporting the same feature set. We only need to check if the accelerator supports a feature, not each vCPU individually. Fix by removing the 'CPUState *cpu' argument from the kvm_arm__supported() functions. Fixes: d70c996df23f ('Use CPUState::kvm_state in kvm_arm_pmu_supported') Reported-by: Haibo Xu Reviewed-by: Andrew Jones Acked-by: Paolo Bonzini Signed-off-by: Philippe Mathieu-Daudé Suggested-by: Paolo Bonzini Signed-off-by: Philippe Mathieu-Daudé Signed-off-by: Peter Maydell --- target/arm/cpu.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'target/arm/cpu.c') diff --git a/target/arm/cpu.c b/target/arm/cpu.c index 5b7a36b5d7..e44e18062c 100644 --- a/target/arm/cpu.c +++ b/target/arm/cpu.c @@ -1108,7 +1108,7 @@ static void arm_set_pmu(Object *obj, bool value, Error **errp) ARMCPU *cpu = ARM_CPU(obj); if (value) { - if (kvm_enabled() && !kvm_arm_pmu_supported(CPU(cpu))) { + if (kvm_enabled() && !kvm_arm_pmu_supported()) { error_setg(errp, "'pmu' feature not supported by KVM on this host"); return; } -- cgit 1.4.1