FAILED: patch "[PATCH] mm/memory_hotplug: fix error handling in" failed to apply to 6.1-stable tree

The patch below does not apply to the 6.1-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y
git checkout FETCH_HEAD
git cherry-pick -x f42ce5f087eb69e47294ababd2e7e6f88a82d308
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2023120918-qualify-refutable-6c2a@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^..

Possible dependencies:

f42ce5f087eb ("mm/memory_hotplug: fix error handling in add_memory_resource()") 1a8c64e11043 ("mm/memory_hotplug: embed vmem_altmap details in memory block") 2d1f649c7c08 ("mm/memory_hotplug: support memmap_on_memory when memmap is not aligned to pageblocks") 85a2b4b08f20 ("mm/memory_hotplug: allow architecture to override memmap on memory support check") e3c2bfdd33a3 ("mm/memory_hotplug: allow memmap on memory hotplug request to fallback")

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From f42ce5f087eb69e47294ababd2e7e6f88a82d308 Mon Sep 17 00:00:00 2001
From: Sumanth Korikkar <[email protected]>
Date: Mon, 20 Nov 2023 15:53:53 +0100
Subject: [PATCH] mm/memory_hotplug: fix error handling in
add_memory_resource()

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().

index bb908289679e..7a5fc89a8652 100644
@@ -1458,7 +1458,7 @@ int __ref add_memory_resource(int nid, struct resource *res, mhp_t mhp_flags)
 	/* 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;
 	}