This is a note to let you know that I've just added the patch titled
mm/memory_hotplug: fix error handling in add_memory_resource()
to the 6.6-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
mm-memory_hotplug-fix-error-handling-in-add_memory_resource.patch
and it can be found in the queue-6.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From f42ce5f087eb69e47294ababd2e7e6f88a82d308 Mon Sep 17 00:00:00 2001
From: Sumanth Korikkar <sumanthk@xxxxxxxxxxxxx>
Date: Mon, 20 Nov 2023 15:53:53 +0100
Subject: mm/memory_hotplug: fix error handling in add_memory_resource()
From: Sumanth Korikkar <sumanthk@xxxxxxxxxxxxx>
commit f42ce5f087eb69e47294ababd2e7e6f88a82d308 upstream.
In add_memory_resource(), creation of memory block devices occurs after
successful call to arch_add_memory(). However, creation of memory block
devices could fail. In that case, arch_remove_memory() is called to
perform necessary cleanup.
Currently with or without altmap support, arch_remove_memory() is always
passed with altmap set to NULL during error handling. This leads to
freeing of struct pages using free_pages(), eventhough the allocation
might have been performed with altmap support via
altmap_alloc_block_buf().
Fix the error handling by passing altmap in arch_remove_memory(). This
ensures the following:
* When altmap is disabled, deallocation of the struct pages array occurs
via free_pages().
* When altmap is enabled, deallocation occurs via vmem_altmap_free().
Link: https://lkml.kernel.org/r/20231120145354.308999-3-sumanthk@xxxxxxxxxxxxx
Fixes: a08a2ae34613 ("mm,memory_hotplug: allocate memmap from the added memory range")
Signed-off-by: Sumanth Korikkar <sumanthk@xxxxxxxxxxxxx>
Reviewed-by: Gerald Schaefer <gerald.schaefer@xxxxxxxxxxxxx>
Acked-by: David Hildenbrand <david@xxxxxxxxxx>
Cc: Alexander Gordeev <agordeev@xxxxxxxxxxxxx>
Cc: Aneesh Kumar K.V <aneesh.kumar@xxxxxxxxxxxxx>
Cc: Anshuman Khandual <anshuman.khandual@xxxxxxx>
Cc: Heiko Carstens <hca@xxxxxxxxxxxxx>
Cc: kernel test robot <lkp@xxxxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxx>
Cc: Oscar Salvador <osalvador@xxxxxxx>
Cc: Vasily Gorbik <gor@xxxxxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx> [5.15+]
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
mm/memory_hotplug.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -1458,7 +1458,7 @@ int __ref add_memory_resource(int nid, s
/* create memory block devices after memory was added */
ret = create_memory_block_devices(start, size, params.altmap, group);
if (ret) {
- arch_remove_memory(start, size, NULL);
+ arch_remove_memory(start, size, params.altmap);
goto error_free;
}
Patches currently in stable-queue which might be from sumanthk@xxxxxxxxxxxxx are
queue-6.6/mm-memory_hotplug-add-missing-mem_hotplug_lock.patch
queue-6.6/mm-memory_hotplug-fix-error-handling-in-add_memory_resource.patch
