On Tue, Apr 5, 2022 at 1:34 AM Ralf Ramsauer
<ralf.ramsa...@oth-regensburg.de> wrote:
>
> Two non-subsequent PTEs can be mapped to subsequent paddrs. In this
> case, walk_pte will erroneously merge them.
>
> Enforce the split up, by tracking the virtual base address.
>
> Let's say we have the mapping:
> 0x81200000 -> 0x89623000 (4K)
> 0x8120f000 -> 0x89624000 (4K)
>
> Before, walk_pte would have shown:
>
> vaddr paddr size attr
> ---------------- ---------------- ---------------- -------
> 0000000081200000 0000000089623000 0000000000002000 rwxu-ad
>
> as it only checks for subsequent paddrs. With this patch, it becomes:
>
> vaddr paddr size attr
> ---------------- ---------------- ---------------- -------
> 0000000081200000 0000000089623000 0000000000001000 rwxu-ad
> 000000008120f000 0000000089624000 0000000000001000 rwxu-ad
>
> Signed-off-by: Ralf Ramsauer <ralf.ramsa...@oth-regensburg.de>
> ---
> target/riscv/monitor.c | 5 ++++-
> 1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/target/riscv/monitor.c b/target/riscv/monitor.c
> index 7efb4b62c1..9dc4cb1156 100644
> --- a/target/riscv/monitor.c
> +++ b/target/riscv/monitor.c
> @@ -84,6 +84,7 @@ static void walk_pte(Monitor *mon, hwaddr base,
> target_ulong start,
> {
> hwaddr pte_addr;
> hwaddr paddr;
> + target_ulong last_start = -1;
> target_ulong pgsize;
> target_ulong pte;
> int ptshift;
> @@ -116,7 +117,8 @@ static void walk_pte(Monitor *mon, hwaddr base,
> target_ulong start,
> * contiguous mapped block details.
> */
Please also update the comments above to mention the new case you added here.
> if ((*last_attr != attr) ||
> - (*last_paddr + *last_size != paddr)) {
> + (*last_paddr + *last_size != paddr) ||
> + (last_start + *last_size != start)) {
> print_pte(mon, va_bits, *vbase, *pbase,
> *last_paddr + *last_size - *pbase, *last_attr);
>
> @@ -125,6 +127,7 @@ static void walk_pte(Monitor *mon, hwaddr base,
> target_ulong start,
> *last_attr = attr;
> }
>
> + last_start = start;
> *last_paddr = paddr;
> *last_size = pgsize;
> } else {
> --
Regards,
Bin
