[170/227] drivers/base/memory: add memory block to memory group after registration succeeded

Commit Message

Andrew Morton March 22, 2022, 9:47 p.m. UTC

From: David Hildenbrand <[e-mail]>
Subject: drivers/base/memory: add memory block to memory group after registration succeeded

If register_memory() fails, we freed the memory block but already added
the memory block to the group list, not good.  Let's defer adding the
block to the memory group to after registering the memory block device.

We do handle it properly during unregister_memory(), but that's not
called when the registration fails.

Link: https://lkml.kernel.org/r/[e-mail]
Fixes: 028fc57a1c36 ("drivers/base/memory: introduce "memory groups" to logically group memory blocks")
Signed-off-by: David Hildenbrand <[e-mail]>
Reviewed-by: Oscar Salvador <[e-mail]>
Acked-by: Michal Hocko <[e-mail]>
Cc: Greg Kroah-Hartman <[e-mail]>
Cc: "Rafael J. Wysocki" <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
---

 drivers/base/memory.c |    8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

Patch

--- a/drivers/base/memory.c~drivers-base-memory-add-memory-block-to-memory-group-after-registration-succeeded
+++ a/drivers/base/memory.c
@@ -665,14 +665,16 @@  static int init_memory_block(unsigned lo
 	mem->nr_vmemmap_pages = nr_vmemmap_pages;
 	INIT_LIST_HEAD(&mem->group_next);
 
+	ret = register_memory(mem);
+	if (ret)
+		return ret;
+
 	if (group) {
 		mem->group = group;
 		list_add(&mem->group_next, &group->memory_blocks);
 	}
 
-	ret = register_memory(mem);
-
-	return ret;
+	return 0;
 }
 
 static int add_memory_block(unsigned long base_section_nr)