[Qemu-devel] BUG: commit 50a2c6e breaks KVM/ARM (reset/init vcpu order)

[Christoffer Dall <christoffer.dall@linaro.org>]

Hi,

I noticed that commit 50a2c6e55fa2ce5a2916a2c206bad2c6b0e06df1 broke
KVM/ARM, because the realize function (arm_cpu_realizefn()) now calls
cpu_reset() before qemu_init_vcpu(), which causes kvm_arm_reset_cpu() to
segfault because it dereferences cpu->cpreg_reset_values, which is not
allocated before kvm_arch_init_vcpu().

Simply changing the order of the reset/init calls (see the tiny patch
below) seems to fix it, but I'm not completely sure this is a clean and
correct fix:


diff --git a/target-arm/cpu.c b/target-arm/cpu.c
index 6c6f2b3..794dcb9 100644
--- a/target-arm/cpu.c
+++ b/target-arm/cpu.c
@@ -370,8 +370,8 @@ static void arm_cpu_realizefn(DeviceState *dev, Error **errp)
 
     init_cpreg_list(cpu);
 
-    cpu_reset(cs);
     qemu_init_vcpu(cs);
+    cpu_reset(cs);
 
     acc->parent_realize(dev, errp);
 }



Please adivce :)

Thanks,
-Christoffer