qemu i386-softmmu segfaults on i386 while testing kdbg hardware interrupts

[Sven Eckelmann]

I tried to boot a kernel with enabled kgdb and kgdb self checks with qemu emulating i386. It works with amd64, but crashes with i386. Tests were done with 19e65b47f60c68d7e8c96aa0a36223c5a0d3422b and qemu 0.11.1-1 on Debian sid.

Backtrace of i386-softmmu/qemu (19e65b47f60c68d7e8c96aa0a36223c5a0d3422b)

[ 15.398435] kgdbts:RUN singlestep [900/1000]
[ 15.683097] kgdbts:RUN hw breakpoint test

Program received signal SIGSEGV, Segmentation fault.
raise_interrupt (intno=1, is_int=0, error_code=0, next_eip_addend=0) at /home/sven/tmp/qemu/target-i386/op_helper.c:1335
1335 env->exception_index = intno;
(gdb) bt
#0 raise_interrupt (intno=1, is_int=0, error_code=0, next_eip_addend=0) at /home/sven/tmp/qemu/target-i386/op_helper.c:1335
#1 0x08182347 in raise_exception (exception_index=1) at /home/sven/tmp/qemu/target-i386/op_helper.c:1351
#2 0x08191e9a in breakpoint_handler (env=0x8467fa8) at /home/sven/tmp/qemu/target-i386/helper.c:1530
#3 0x08125e84 in cpu_handle_debug_exception (env1=0x8467fa8) at /home/sven/tmp/qemu/cpu-exec.c:209
#4 cpu_x86_exec (env1=0x8467fa8) at /home/sven/tmp/qemu/cpu-exec.c:274
#5 0x08052680 in qemu_cpu_exec (argc=0, argv=0x0, envp=0x6461) at /home/sven/tmp/qemu/vl.c:4021
#6 tcg_cpu_exec (argc=0, argv=0x0, envp=0x6461) at /home/sven/tmp/qemu/vl.c:4052
#7 main_loop (argc=0, argv=0x0, envp=0x6461) at /home/sven/tmp/qemu/vl.c:4167
#8 main (argc=0, argv=0x0, envp=0x6461) at /home/sven/tmp/qemu/vl.c:6124

It was run with `/home/sven/tmp/qemu/i386-softmmu/qemu -m 1024 -kernel linux-2.6.32.qemu -drive file=root.cow3,if=virtio -net nic,macaddr=02:ca:ff:ee:ba:43,model=virtio,vlan=3 -net tap,ifname=tap3,vlan=3,script=no -nographic`

[Sven Eckelmann (sven-eckelmann)]

Seems to be fixed in qemu 0.12.5 (Debian 0.12.5+dfsg-2).

[Sven Eckelmann (sven-eckelmann)]

My fault. it is still their... did my test wrong

[Sven Eckelmann (sven-eckelmann)]

Works with 0.13.0 (Debian 0.13.0+dfsg-2). Probably 63a54736f31f9e11da6fb52319bba26e7d24f571 was the fix