Re: [Qemu-devel] Xtensa misuse of tb_invalidate_phys_page_range()?

[Avi Kivity <avi@redhat.com>]

On 03/19/2012 03:51 PM, Max Filippov wrote:
> > void HELPER(wsr_ibreaka)(uint32_t i, uint32_t v)
> > {
> >    if (env->sregs[IBREAKENABLE] & (1 << i) && env->sregs[IBREAKA + i]
> > != v) {
> >        tb_invalidate_phys_page_range(
> >                env->sregs[IBREAKA + i], env->sregs[IBREAKA + i] + 1, 0);
> >        tb_invalidate_phys_page_range(v, v + 1, 0);
> >    }
> >    env->sregs[IBREAKA + i] = v;
> > }
> >
> > tb_invalidate_phys_page_range() expects a virtual address in user mode,
> > and a ram_addr_t in system mode.  I'm guessing that v is a virtual address?
>
> Yes, it's a virtual address here, as well as in wsr_lbeg/wsr_lend helpers.
> I made a test for it and it actually fails. I wonder how could it stay unnoticed
> that long :()

There are many silent breakages like that, don't worry.

> > This needs to be fixed for system mode if so (and in any case - even if
> > it's a physical address, it needs to be translated to a ram_addr_t).
>
> Sure. Will try to fix it, though it's completely unclear to me now
> how to do it efficiently.

Since I'm rewriting this area, don't worry about efficiency.  Let's get
it correct and after the rewrite we can reexamine efficiency.

I imagine you'll need something like breakpoint_invalidate().

-- 
error compiling committee.c: too many arguments to function