Re: [PATCH v4 17/28] linux-user: Remove dead code

[Laurent Vivier]

Le 03/03/2021 à 22:46, Philippe Mathieu-Daudé a écrit :
> We can not use watchpoints in user-mode emulation because we
> need the softmmu slow path to detect accesses to watchpointed
> memory. This code is expanded as empty stub in "hw/core/cpu.h"
> anyway, so we can drop it.
> 
> Reviewed-by: Laurent Vivier <laurent@vivier.eu>
> Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
> ---
>  linux-user/main.c | 5 -----
>  1 file changed, 5 deletions(-)
> 
> diff --git a/linux-user/main.c b/linux-user/main.c
> index 81f48ff54ed..d7af3ffbc22 100644
> --- a/linux-user/main.c
> +++ b/linux-user/main.c
> @@ -200,7 +200,6 @@ CPUArchState *cpu_copy(CPUArchState *env)
>      CPUState *new_cpu = cpu_create(cpu_type);
>      CPUArchState *new_env = new_cpu->env_ptr;
>      CPUBreakpoint *bp;
> -    CPUWatchpoint *wp;
>  
>      /* Reset non arch specific state */
>      cpu_reset(new_cpu);
> @@ -211,13 +210,9 @@ CPUArchState *cpu_copy(CPUArchState *env)
>         Note: Once we support ptrace with hw-debug register access, make sure
>         BP_CPU break/watchpoints are handled correctly on clone. */
>      QTAILQ_INIT(&new_cpu->breakpoints);
> -    QTAILQ_INIT(&new_cpu->watchpoints);
>      QTAILQ_FOREACH(bp, &cpu->breakpoints, entry) {
>          cpu_breakpoint_insert(new_cpu, bp->pc, bp->flags, NULL);
>      }
> -    QTAILQ_FOREACH(wp, &cpu->watchpoints, entry) {
> -        cpu_watchpoint_insert(new_cpu, wp->vaddr, wp->len, wp->flags, NULL);
> -    }
>  
>      return new_env;
>  }
> 

Applied to my linux-user-for-6.1 branch.

Thanks,
Laurent