diff options
| author | Anthony Xu <anthony.xu@intel.com> | 2017-05-09 15:37:12 -0700 |
|---|---|---|
| committer | Stefan Hajnoczi <stefanha@redhat.com> | 2017-05-12 10:37:40 -0400 |
| commit | 5651743c908d8c3b1ff0192ce9543a502ec7a206 (patch) | |
| tree | 25af1e28f79426dab3f032483859ed7faef13c86 /qom | |
| parent | ecc1f5adeec4e3324d1b695a7c54e3967c526949 (diff) | |
trace: add sanity check
If trace backend is set to TRACE_NOP, trace_get_vcpu_event_count
returns 0, cause bitmap_new call abort.
The abort can be triggered as follows:
$ ./configure --enable-trace-backend=nop --target-list=x86_64-softmmu
$ gdb ./x86_64-softmmu/qemu-system-x86_64 -M q35,accel=kvm -m 1G
(gdb) bt
#0 0x00007ffff04e25f7 in raise () from /lib64/libc.so.6
#1 0x00007ffff04e3ce8 in abort () from /lib64/libc.so.6
#2 0x00005555559de905 in bitmap_new (nbits=<optimized out>)
at /home/root/git/qemu2.git/include/qemu/bitmap.h:96
#3 cpu_common_initfn (obj=0x555556621d30) at qom/cpu.c:399
#4 0x0000555555a11869 in object_init_with_type (obj=0x555556621d30, ti=0x55555656bbb0) at qom/object.c:341
#5 0x0000555555a11869 in object_init_with_type (obj=0x555556621d30, ti=0x55555656bd30) at qom/object.c:341
#6 0x0000555555a11efc in object_initialize_with_type (data=data@entry=0x555556621d30, size=76560,
type=type@entry=0x55555656bd30) at qom/object.c:376
#7 0x0000555555a12061 in object_new_with_type (type=0x55555656bd30) at qom/object.c:484
#8 0x0000555555a121c5 in object_new (typename=typename@entry=0x555556550340 "qemu64-x86_64-cpu")
at qom/object.c:494
#9 0x00005555557f6e3d in pc_new_cpu (typename=typename@entry=0x555556550340 "qemu64-x86_64-cpu", apic_id=0,
errp=errp@entry=0x5555565391b0 <error_fatal>) at /home/root/git/qemu2.git/hw/i386/pc.c:1101
#10 0x00005555557fa33e in pc_cpus_init (pcms=pcms@entry=0x5555565f9690)
at /home/root/git/qemu2.git/hw/i386/pc.c:1184
#11 0x00005555557fe0f6 in pc_q35_init (machine=0x5555565f9690) at /home/root/git/qemu2.git/hw/i386/pc_q35.c:121
#12 0x000055555574fbad in main (argc=<optimized out>, argv=<optimized out>, envp=<optimized out>) at vl.c:4562
Signed-off-by: Anthony Xu <anthony.xu@intel.com>
Message-id: 1494369432-15418-1-git-send-email-anthony.xu@intel.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Diffstat (limited to 'qom')
| -rw-r--r-- | qom/cpu.c | 6 |
1 files changed, 5 insertions, 1 deletions
@@ -382,6 +382,7 @@ static void cpu_common_unrealizefn(DeviceState *dev, Error **errp) static void cpu_common_initfn(Object *obj) { + uint32_t count; CPUState *cpu = CPU(obj); CPUClass *cc = CPU_GET_CLASS(obj); @@ -396,7 +397,10 @@ static void cpu_common_initfn(Object *obj) QTAILQ_INIT(&cpu->breakpoints); QTAILQ_INIT(&cpu->watchpoints); - cpu->trace_dstate = bitmap_new(trace_get_vcpu_event_count()); + count = trace_get_vcpu_event_count(); + if (count) { + cpu->trace_dstate = bitmap_new(count); + } cpu_exec_initfn(cpu); } |