exec: Relax range check in ram_block_discard_range()

We want to make use of ram_block_discard_range() in the RAM block resize
callback when growing a RAM block, *before* used_length is changed.
Let's relax the check. As RAM blocks always mmap the whole max_length area,
we cannot corrupt unrelated data.

Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210429112708.12291-6-david@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
This commit is contained in:
David Hildenbrand 2021-04-29 13:27:03 +02:00 committed by Dr. David Alan Gilbert
parent c7c0e72408
commit dcdc460767

View File

@ -3500,7 +3500,7 @@ int ram_block_discard_range(RAMBlock *rb, uint64_t start, size_t length)
goto err;
}
if ((start + length) <= rb->used_length) {
if ((start + length) <= rb->max_length) {
bool need_madvise, need_fallocate;
if (!QEMU_IS_ALIGNED(length, rb->page_size)) {
error_report("ram_block_discard_range: Unaligned length: %zx",
@ -3567,7 +3567,7 @@ int ram_block_discard_range(RAMBlock *rb, uint64_t start, size_t length)
} else {
error_report("ram_block_discard_range: Overrun block '%s' (%" PRIu64
"/%zx/" RAM_ADDR_FMT")",
rb->idstr, start, length, rb->used_length);
rb->idstr, start, length, rb->max_length);
}
err: