Re: [Qemu-devel] [PULL 09/10] Revert "target/aarch64: optimize indirect branches" - Philippe Mathieu-Daudé

From: "Philippe Mathieu-Daudé" <f4bug@amsat.org>
To: Richard Henderson <rth@twiddle.net>, qemu-devel@nongnu.org
Cc: peter.maydell@linaro.org
Subject: Re: [Qemu-devel] [PULL 09/10] Revert "target/aarch64: optimize indirect branches"
Date: Wed, 14 Jun 2017 11:27:52 -0300	[thread overview]
Message-ID: <7bcb68c3-e1d3-40bf-6db8-85b7e8a4aa14@amsat.org> (raw)
In-Reply-To: <20170614052311.13785-10-rth@twiddle.net>

Can this pull wait you test last series sent by Alex Bennée with the 
following patch?

I dont have Alpha images to test on.

"tcg-runtime: short-circuit lookup_tb_ptr on IRQs"

On 06/14/2017 02:23 AM, Richard Henderson wrote:
> This reverts commit e75449a346bf558296966a44277bfd93412c6da6.
>
> This patch appears to induce lockups, or maybe livelocks, while
> booting a Linux kernel.  The assumption is that there is a bug
> elsewhere within QEMU, but reverting the patch allows normal work
> to continue in the meantime.
>
> Signed-off-by: Richard Henderson <rth@twiddle.net>
> ---
>  target/arm/translate-a64.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/target/arm/translate-a64.c b/target/arm/translate-a64.c
> index 860e279..ab61d96 100644
> --- a/target/arm/translate-a64.c
> +++ b/target/arm/translate-a64.c
> @@ -11367,7 +11367,8 @@ void gen_intermediate_code_a64(ARMCPU *cpu, TranslationBlock *tb)
>              gen_a64_set_pc_im(dc->pc);
>              /* fall through */
>          case DISAS_JUMP:
> -            tcg_gen_lookup_and_goto_ptr(cpu_pc);
> +            /* indicate that the hash table must be used to find the next TB */
> +            tcg_gen_exit_tb(0);
>              break;
>          case DISAS_TB_JUMP:
>          case DISAS_EXC:
>