Hi, These are debug patches only but represent how much I have narrowed down the problem so far. I've included Thomas' patch to fix the thread=single|multi option as that is currently broken upstream. So far it seems though the problem is unrelated to multi-threading.
As discussed in the other thread I found not returning to a tb_htable_lookup but adding it to the tb_jmp_cache made the problem go away. I also tried various printfs but they also seemed to un-wedge the hang I was seeing. It is not really a hang rather than a busy-spin that will eventually given enough time unwind. So added a new TB flag (is_magic) which if set would skip returning the code ptr and default to exiting the loop via the epilogue and set it for all DISAS_JUMP/DISAS_UPDATE paths that trigger lookup_and_goto_ptr. After selectively commenting them out I found the RET instruction is responsible for my particular fail case. I find this confusing because BL and BLR basically do the same thing and they seem to work fine. I have an uneasy feeling there is some subtle black magic in the interaction between cpu_get_tb_cpu_state(env, &pc, &cs_base, &flags), addr and the TCGv cpu_pc but I haven't nailed it down. I'm posting this for those that still have some Friday left in case it prompts any thoughts. Over to you, hopefully inspiration will strike before I return to the fray on Monday ;-) Cheers, Alex Bennée (2): tcg-runtime: light re-factor of lookup_tb_ptr translate-a64: fix lookup_tb_ptr hang (DEBUG!) Thomas Huth (1): vl: Fix broken thread=xxx option of the --accel parameter include/exec/exec-all.h | 2 ++ target/arm/translate-a64.c | 21 +++++++++++++++++---- target/arm/translate.h | 2 ++ tcg-runtime.c | 37 +++++++++++++++++++++---------------- vl.c | 13 +++++-------- 5 files changed, 47 insertions(+), 28 deletions(-) -- 2.13.0
