On Thu, 3 Nov 2016 23:14:05 +0000
Peter Maydell <peter.mayd...@linaro.org> wrote:
> On 3 November 2016 at 17:30, Julian Brown <jul...@codesourcery.com>
> wrote:
> > In BE32 mode, sub-word size watchpoints can fail to trigger because
> > the address of the access is adjusted in the opcode helpers before
> > being compared with the watchpoint registers. This patch reversed
> > the address adjustment before performing the comparison.
> >
> > Signed-off-by: Julian Brown <jul...@codesourcery.com>
> > ---
> > exec.c | 13 +++++++++++++
> > 1 file changed, 13 insertions(+)
> >
> > diff --git a/exec.c b/exec.c
> > index 4c84389..eadab54 100644
> > --- a/exec.c
> > +++ b/exec.c
> > @@ -2047,6 +2047,19 @@ static void check_watchpoint(int offset, int
> > len, MemTxAttrs attrs, int flags) return;
> > }
> > vaddr = (cpu->mem_io_vaddr & TARGET_PAGE_MASK) + offset;
> > +#if defined(TARGET_ARM) && !defined(CONFIG_USER_ONLY)
> > + /* In BE32 system mode, target memory is stored byteswapped
> > (FIXME:
> > + relative to a little-endian host system), and by the time
> > we reach here
> > + (via an opcode helper) the addresses of subword accesses
> > have been
> > + adjusted to account for that, which means that watchpoints
> > will not
> > + match. Undo the adjustment here. */
> > + if (arm_sctlr_b(env)) {
> > + if (len == 1)
> > + vaddr ^= 3;
> > + else if (len == 2)
> > + vaddr ^= 2;
> > + }
> > +#endif
>
> No target-CPU specific code in exec.c, please...
Yeah, I'd imagine not. I struggled with this one. Any suggestions for a
better way to do this?
Thanks,
Julian
