Re: [PATCH v4 16/16] cputlb: Pass retaddr to tb_check_watchpoint

["Alex Bennée" <alex.bennee@linaro.org>]

Richard Henderson <richard.henderson@linaro.org> writes:

> Fixes the previous TLB_WATCHPOINT patches because we are currently
> failing to set cpu->mem_io_pc with the call to cpu_check_watchpoint.
> Pass down the retaddr directly because it's readily available.
>
> Fixes: 50b107c5d61
> Reviewed-by: David Hildenbrand <david@redhat.com>
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>

> ---
>  accel/tcg/translate-all.h | 2 +-
>  accel/tcg/translate-all.c | 6 +++---
>  exec.c                    | 2 +-
>  3 files changed, 5 insertions(+), 5 deletions(-)
>
> diff --git a/accel/tcg/translate-all.h b/accel/tcg/translate-all.h
> index 135c1ea96a..a557b4e2bb 100644
> --- a/accel/tcg/translate-all.h
> +++ b/accel/tcg/translate-all.h
> @@ -30,7 +30,7 @@ void tb_invalidate_phys_page_fast(struct page_collection *pages,
>                                    tb_page_addr_t start, int len,
>                                    uintptr_t retaddr);
>  void tb_invalidate_phys_page_range(tb_page_addr_t start, tb_page_addr_t end);
> -void tb_check_watchpoint(CPUState *cpu);
> +void tb_check_watchpoint(CPUState *cpu, uintptr_t retaddr);
>
>  #ifdef CONFIG_USER_ONLY
>  int page_unprotect(target_ulong address, uintptr_t pc);
> diff --git a/accel/tcg/translate-all.c b/accel/tcg/translate-all.c
> index db77fb221b..66d4bc4341 100644
> --- a/accel/tcg/translate-all.c
> +++ b/accel/tcg/translate-all.c
> @@ -2142,16 +2142,16 @@ static bool tb_invalidate_phys_page(tb_page_addr_t addr, uintptr_t pc)
>  #endif
>
>  /* user-mode: call with mmap_lock held */
> -void tb_check_watchpoint(CPUState *cpu)
> +void tb_check_watchpoint(CPUState *cpu, uintptr_t retaddr)
>  {
>      TranslationBlock *tb;
>
>      assert_memory_lock();
>
> -    tb = tcg_tb_lookup(cpu->mem_io_pc);
> +    tb = tcg_tb_lookup(retaddr);
>      if (tb) {
>          /* We can use retranslation to find the PC.  */
> -        cpu_restore_state_from_tb(cpu, tb, cpu->mem_io_pc, true);
> +        cpu_restore_state_from_tb(cpu, tb, retaddr, true);
>          tb_phys_invalidate(tb, -1);
>      } else {
>          /* The exception probably happened in a helper.  The CPU state should
> diff --git a/exec.c b/exec.c
> index b3df826039..8a0a6613b1 100644
> --- a/exec.c
> +++ b/exec.c
> @@ -2758,7 +2758,7 @@ void cpu_check_watchpoint(CPUState *cpu, vaddr addr, vaddr len,
>                  cpu->watchpoint_hit = wp;
>
>                  mmap_lock();
> -                tb_check_watchpoint(cpu);
> +                tb_check_watchpoint(cpu, ra);
>                  if (wp->flags & BP_STOP_BEFORE_ACCESS) {
>                      cpu->exception_index = EXCP_DEBUG;
>                      mmap_unlock();


--
Alex Bennée