migration/ram: Rely on used_length for uffd_change_protection()
ram_mig_ram_block_resized() will abort migration (including background snapshots) when resizing a RAMBlock. ram_block_populate_read() will only populate RAM up to used_length, so at least for anonymous memory protecting everything between used_length and max_length won't actually be protected and is just a NOP. So let's only protect everything up to used_length. Note: it still makes sense to register uffd-wp for max_length, such that RAM_UF_WRITEPROTECT is independent of a changing used_length. Reviewed-by: Peter Xu <peterx@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: David Hildenbrand <david@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
This commit is contained in:
parent
7cc8e9e0fa
commit
59bcc049c1
|
@ -1901,7 +1901,7 @@ int ram_write_tracking_start(void)
|
||||||
|
|
||||||
/* Apply UFFD write protection to the block memory range */
|
/* Apply UFFD write protection to the block memory range */
|
||||||
if (uffd_change_protection(rs->uffdio_fd, block->host,
|
if (uffd_change_protection(rs->uffdio_fd, block->host,
|
||||||
block->max_length, true, false)) {
|
block->used_length, true, false)) {
|
||||||
goto fail;
|
goto fail;
|
||||||
}
|
}
|
||||||
|
|
||||||
|
|
Loading…
Reference in New Issue