Re: [Qemu-ppc] qemu-ppc crashing on x86

[Alexander Graf]

On 03.02.2014, at 23:31, Cedric Le Goater <address@hidden> wrote:

> Hi,
> 
> The "latest" qemu-ppc is crashing when running a ppc guest on x86. I was 
> using a 
> relatively old version until recently, when Tom Musta's patches were merged a 
> few 
> days ago. 
> 
> Anyhow, here are some info on the crash. 
> 
> qemu-system-ppc64: /home/legoater/work/linux/qemu-agraf.git/tcg/tcg.c:515: 
> tcg_temp_new_internal: Assertion `ts->base_type == type' failed.
> Aborted (core dumped)
> 
> and the core stack trace :
> 
> #0  0xb7173424 in __kernel_vsyscall ()
> #1  0xb6d73941 in raise () from /lib/i386-linux-gnu/i686/cmov/libc.so.6
> #2  0xb6d76d72 in abort () from /lib/i386-linux-gnu/i686/cmov/libc.so.6
> #3  0xb6d6cb58 in __assert_fail () from 
> /lib/i386-linux-gnu/i686/cmov/libc.so.6
> #4  0xb75c4a4a in tcg_temp_new_internal (type=TCG_TYPE_I32, temp_local=0)
>    at /home/legoater/work/linux/qemu-agraf.git/tcg/tcg.c:515
> #5  0xb75c4c70 in tcg_temp_new_internal_i32 (temp_local=0)
>    at /home/legoater/work/linux/qemu-agraf.git/tcg/tcg.c:559
> #6  0xb75beb03 in tcg_temp_new_i32 () at 
> /home/legoater/work/linux/qemu-agraf.git/tcg/tcg.h:569
> #7  0xb75c4efb in tcg_const_i32 (val=25) at 
> /home/legoater/work/linux/qemu-agraf.git/tcg/tcg.c:606
> #8  0xb75bf0a4 in tcg_gen_shli_i32 (ret=..., arg1=..., arg2=25)
>    at /home/legoater/work/linux/qemu-agraf.git/tcg/tcg-op.h:612
> #9  0xb75c5517 in tcg_gen_shifti_i64 (ret=..., arg1=..., c=7, right=1, 
> arith=0)
>    at /home/legoater/work/linux/qemu-agraf.git/tcg/tcg.c:790
> #10 0xb7543d21 in tcg_gen_shri_i64 (ret=..., arg1=..., arg2=7)
>    at /home/legoater/work/linux/qemu-agraf.git/tcg/tcg-op.h:985
> #11 0xb755ff4f in gen_rlwinm (ctx=0x9c7c9e3c)
>    at /home/legoater/work/linux/qemu-agraf.git/target-ppc/translate.c:1636
> #12 0xb75ba884 in gen_intermediate_code_internal (cpu=0xb964e210, 
> tb=0x9d5065b4, search_pc=false)
>    at /home/legoater/work/linux/qemu-agraf.git/target-ppc/translate.c:11001
> #13 0xb75bac50 in gen_intermediate_code (env=0xb964e2cc, tb=0x9d5065b4)
>    at /home/legoater/work/linux/qemu-agraf.git/target-ppc/translate.c:11058
> #14 0xb75caec3 in cpu_ppc_gen_code (env=0xb964e2cc, tb=0x9d5065b4, 
> gen_code_size_ptr=0x9c7c9f7c)
>    at /home/legoater/work/linux/qemu-agraf.git/translate-all.c:159
> #15 0xb75cc28b in tb_gen_code (env=0xb964e2cc, pc=19524, cs_base=0, flags=0, 
> cflags=0)
>    at /home/legoater/work/linux/qemu-agraf.git/translate-all.c:967
> #16 0xb7431fa4 in tb_find_slow (env=0xb964e2cc, pc=19524, cs_base=0, flags=0)
>    at /home/legoater/work/linux/qemu-agraf.git/cpu-exec.c:163
> #17 0xb743219d in tb_find_fast (env=0xb964e2cc) at 
> /home/legoater/work/linux/qemu-agraf.git/cpu-exec.c:190
> #18 0xb74325cf in cpu_ppc_exec (env=0xb964e2cc) at 
> /home/legoater/work/linux/qemu-agraf.git/cpu-exec.c:604
> #19 0xb7435bb8 in tcg_cpu_exec (env=0xb964e2cc) at 
> /home/legoater/work/linux/qemu-agraf.git/cpus.c:1255
> #20 0xb7435cfc in tcg_exec_all () at 
> /home/legoater/work/linux/qemu-agraf.git/cpus.c:1288
> #21 0xb7435061 in qemu_tcg_cpu_thread_fn (arg=0xb964e210) at 
> /home/legoater/work/linux/qemu-agraf.git/cpus.c:954
> #22 0xb6eb1c39 in start_thread () from 
> /lib/i386-linux-gnu/i686/cmov/libpthread.so.0
> #23 0xb6e1e78e in clone () from /lib/i386-linux-gnu/i686/cmov/libc.so.6
> (gdb) up
> #1  0xb6d73941 in raise () from /lib/i386-linux-gnu/i686/cmov/libc.so.6
> (gdb) up
> #2  0xb6d76d72 in abort () from /lib/i386-linux-gnu/i686/cmov/libc.so.6
> (gdb) up
> #3  0xb6d6cb58 in __assert_fail () from 
> /lib/i386-linux-gnu/i686/cmov/libc.so.6
> (gdb) up
> #4  0xb75c4a4a in tcg_temp_new_internal (type=TCG_TYPE_I32, temp_local=0)
>    at /home/legoater/work/linux/qemu-agraf.git/tcg/tcg.c:515
> 515           assert(ts->base_type == type);
> (gdb) p type
> $1 = TCG_TYPE_I32
> (gdb) p *ts
> $2 = {base_type = TCG_TYPE_I64, type = TCG_TYPE_I32, val_type = 0, reg = 6, 
> val = 0, mem_reg = 4, 
>  mem_offset = 128, fixed_reg = 0, mem_coherent = 0, mem_allocated = 0, 
> temp_local = 0, temp_allocated = 1, 
>  name = 0x0}
> 
> 
> It might be related to commit 0ec9eabc7f6020418e1f3b3273d1dd701f7f87f9
> (tcg: Use bitmaps for free temporaries). I tried a few possible fixes 
> but I did not have much success. Any idea ? 

You're running on a 32bit host (which is a pretty bad idea when running 
qemu-system-ppc64 since it'll split all 64bit registers into two 32bit ones) 
OS. There was a bug with TCG there which I fixed a while ago (TCG: Fix 
I64-on-32bit-host temporaries).

I just rebased my tree against current upstream and checked - the fix is 
definitely in now. So you should be able to get a working system through a more 
recent checkout. Except for the VGA problem discussed earlier on this list of 
course.


Alex