aboutsummaryrefslogtreecommitdiff
path: root/migration
diff options
context:
space:
mode:
authorDavid Hildenbrand <david@redhat.com>2023-01-05 13:45:25 +0100
committerJuan Quintela <quintela@redhat.com>2023-02-06 19:22:56 +0100
commit72ef3a370836aa07261ad7aaeea27ed5cbcee342 (patch)
treeac29b9ef11fa628301ba6d0c0583e8997dec8e5e /migration
parent5f19a4491941fdc5c5b50ce4ade6ffffe0f591b4 (diff)
downloadqemu-72ef3a370836aa07261ad7aaeea27ed5cbcee342.zip
qemu-72ef3a370836aa07261ad7aaeea27ed5cbcee342.tar.gz
qemu-72ef3a370836aa07261ad7aaeea27ed5cbcee342.tar.bz2
migration/ram: Fix error handling in ram_write_tracking_start()
If something goes wrong during uffd_change_protection(), we would miss to unregister uffd-wp and not release our reference. Fix it by performing the uffd_change_protection(true) last. Note that a uffd_change_protection(false) on the recovery path without a prior uffd_change_protection(false) is fine. Fixes: 278e2f551a09 ("migration: support UFFD write fault processing in ram_save_iterate()") Cc: qemu-stable@nongnu.org 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>
Diffstat (limited to 'migration')
-rw-r--r--migration/ram.c5
1 files changed, 3 insertions, 2 deletions
diff --git a/migration/ram.c b/migration/ram.c
index ba228ee..73e5ca9 100644
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -1896,13 +1896,14 @@ int ram_write_tracking_start(void)
block->max_length, UFFDIO_REGISTER_MODE_WP, NULL)) {
goto fail;
}
+ block->flags |= RAM_UF_WRITEPROTECT;
+ memory_region_ref(block->mr);
+
/* Apply UFFD write protection to the block memory range */
if (uffd_change_protection(rs->uffdio_fd, block->host,
block->max_length, true, false)) {
goto fail;
}
- block->flags |= RAM_UF_WRITEPROTECT;
- memory_region_ref(block->mr);
trace_ram_write_tracking_ramblock_start(block->idstr, block->page_size,
block->host, block->max_length);