6.1-stable review patch. If anyone has any objections, please let me know.
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From: Sumanth Korikkar sumanthk@linux.ibm.com
[ Upstream commit f42ce5f087eb69e47294ababd2e7e6f88a82d308 ]
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@linux.ibm.com Fixes: a08a2ae34613 ("mm,memory_hotplug: allocate memmap from the added memory range") Signed-off-by: Sumanth Korikkar sumanthk@linux.ibm.com Reviewed-by: Gerald Schaefer gerald.schaefer@linux.ibm.com Acked-by: David Hildenbrand david@redhat.com Cc: Alexander Gordeev agordeev@linux.ibm.com Cc: Aneesh Kumar K.V aneesh.kumar@linux.ibm.com Cc: Anshuman Khandual anshuman.khandual@arm.com Cc: Heiko Carstens hca@linux.ibm.com Cc: kernel test robot lkp@intel.com Cc: Michal Hocko mhocko@suse.com Cc: Oscar Salvador osalvador@suse.de Cc: Vasily Gorbik gor@linux.ibm.com Cc: stable@vger.kernel.org [5.15+] Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- mm/memory_hotplug.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index d02722bbfcf33..3b9d3a4b43869 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -1382,7 +1382,7 @@ int __ref add_memory_resource(int nid, struct resource *res, mhp_t mhp_flags) ret = create_memory_block_devices(start, size, mhp_altmap.alloc, group); if (ret) { - arch_remove_memory(start, size, NULL); + arch_remove_memory(start, size, params.altmap); goto error; }