Re: [PATCH v3 2/8] accel/tcg: suppress IRQ check for special TBs

[Richard Henderson <richard.henderson@linaro.org>]

On 11/29/21 3:09 PM, Alex Bennée wrote:
> When we set cpu->cflags_next_tb it is because we want to carefully
> control the execution of the next TB. Currently there is a race that
> causes the second stage of watchpoint handling to get ignored if an
> IRQ is processed before we finish executing the instruction that
> triggers the watchpoint. Use the new CF_NOIRQ facility to avoid the
> race.
> 
> We also suppress IRQs when handling precise self modifying code to
> avoid unnecessary bouncing.
> 
> Signed-off-by: Alex Bennée<alex.bennee@linaro.org>
> Cc: Pavel Dovgalyuk<pavel.dovgalyuk@ispras.ru>
> Fixes:https://gitlab.com/qemu-project/qemu/-/issues/245
> 
> ---
> v2
>    - split the CF_NOIRQ implementation
>    - only apply CF_NOIRQ for watchpoints/SMC handling
>    - minor reword of commit
> v3
>    - add additional two cases of | CF_NOIRQ
> ---
>   accel/tcg/cpu-exec.c      | 9 +++++++++
>   accel/tcg/translate-all.c | 4 ++--
>   softmmu/physmem.c         | 4 ++--
>   3 files changed, 13 insertions(+), 4 deletions(-)

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

r~