[PATCH v2 7/8] powerpc/mm: remove linear mapping if __add_pages() fails in arch_add_memory()

From: David Hildenbrand
Date: Wed Nov 11 2020 - 09:54:06 EST


Let's revert what we did in case seomthing goes wrong and we return an
error - as already done on arm64 and s390x.

Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxx>
Cc: Rashmica Gupta <rashmica.g@xxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Mike Rapoport <rppt@xxxxxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxx>
Cc: Oscar Salvador <osalvador@xxxxxxx>
Cc: Wei Yang <richard.weiyang@xxxxxxxxxxxxxxxxx>
Signed-off-by: David Hildenbrand <david@xxxxxxxxxx>
---
arch/powerpc/mm/mem.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
index c5755b9efb64..8b946ec68d1b 100644
--- a/arch/powerpc/mm/mem.c
+++ b/arch/powerpc/mm/mem.c
@@ -170,7 +170,10 @@ int __ref arch_add_memory(int nid, u64 start, u64 size,
rc = arch_create_linear_mapping(nid, start, size, params);
if (rc)
return rc;
- return __add_pages(nid, start_pfn, nr_pages, params);
+ rc = __add_pages(nid, start_pfn, nr_pages, params);
+ if (rc)
+ arch_remove_linear_mapping(start, size);
+ return rc;
}

void __ref arch_remove_memory(int nid, u64 start, u64 size,
--
2.26.2