Re: [Qemu-devel] [PATCH] exec.c: fix setting 1-byte-long watchpoints

[Peter Maydell]

On 17 September 2014 22:03, Max Filippov <address@hidden> wrote:
> With commit 05068c0dfb5b 'exec.c: Relax restrictions on watchpoint length
> and alignment' it's no longer possible to set 1-byte-long watchpoint
> because of incorrect address range check.
> Fix that by changing condition that checks for address wraparound.
>
> Signed-off-by: Max Filippov <address@hidden>
> ---
>  exec.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/exec.c b/exec.c
> index 2b24651..759055d 100644
> --- a/exec.c
> +++ b/exec.c
> @@ -595,7 +595,7 @@ int cpu_watchpoint_insert(CPUState *cpu, vaddr addr, 
> vaddr len,
>      CPUWatchpoint *wp;
>
>      /* forbid ranges which are empty or run off the end of the address space 
> */
> -    if (len == 0 || (addr + len - 1) <= addr) {
> +    if (len == 0 || (addr + len - 1) < addr) {
>          error_report("tried to set invalid watchpoint at %"
>                       VADDR_PRIx ", len=%" VADDR_PRIu, addr, len);
>          return -EINVAL;

Reviewed-by: Peter Maydell <address@hidden>

and sorry for the breakage; I'll apply this to master in a bit.

thanks
-- PMM