So that we pass a same-page range to tb_invalidate_phys_page_range,
instead of always passing an end address that could be on a different
page.
As discussed with Peter Maydell on the list, tb_invalidate_phys_page_range
doesn't actually do much with 'end', which explains why we have never
hit a bug despite going against what the comment on top of
tb_invalidate_phys_page_range requires:
> * Invalidate all TBs which intersect with the target physical address range
> * [start;end[. NOTE: start and end must refer to the *same* physical page.
The appended honours the comment, which avoids confusion.
While at it, rework the loop into a for loop, which is less error prone
(e.g. "continue" won't result in an infinite loop).
Signed-off-by: Emilio G. Cota <c...@braap.org>
---
accel/tcg/translate-all.c | 12 ++++++++----
1 file changed, 8 insertions(+), 4 deletions(-)
diff --git a/accel/tcg/translate-all.c b/accel/tcg/translate-all.c
index 64d099b..e8f663f 100644
--- a/accel/tcg/translate-all.c
+++ b/accel/tcg/translate-all.c
@@ -1372,10 +1372,14 @@ TranslationBlock *tb_gen_code(CPUState *cpu,
*/
static void tb_invalidate_phys_range_1(tb_page_addr_t start, tb_page_addr_t
end)
{
- while (start < end) {
- tb_invalidate_phys_page_range(start, end, 0);
- start &= TARGET_PAGE_MASK;
- start += TARGET_PAGE_SIZE;
+ tb_page_addr_t next;
+
+ for (next = (start & TARGET_PAGE_MASK) + TARGET_PAGE_SIZE;
+ start < end;
+ start = next, next += TARGET_PAGE_SIZE) {
+ tb_page_addr_t bound = MIN(next, end);
+
+ tb_invalidate_phys_page_range(start, bound, 0);
}
}
--
2.7.4
