Re: [Qemu-devel] qemu physical address

[Blue Swirl]

On Wed, Apr 18, 2012 at 01:28, Xin Tong <address@hidden> wrote:
> I am reading how qemu refill TLB working.
>
> target-i386/helper.c
>
>    pte = pte & env->a20_mask;
>
>    /* Even if 4MB pages, we map only one 4KB page in the cache to
>       avoid filling it too fast */
>    page_offset = (addr & TARGET_PAGE_MASK) & (page_size - 1);
>    paddr = (pte & TARGET_PAGE_MASK) + page_offset;
>    vaddr = virt_addr + page_offset;
>
>
> How can the paddr be bigger than 4G even though i gave the machine
> 4096 MB of memory ( i.e. qemu -m 4096 ...). should not paddr be within
> 0 - 4G-1 ?

No. There's PAE and the same code is used by both i386 and x86_64.

>
> Thanks
>
> Xin
>