From e96c6b8f212a510c9b22362de519f6e1d7920de5 Mon Sep 17 00:00:00 2001
From: Song Shuai <songshuaishuai@tinylab.org>
Date: Sat, 24 Jun 2023 11:26:07 +0800
Subject: [PATCH] memblock: report failures when memblock_can_resize is not set
The callers of memblock_reserve() do not check the return value
presuming that memblock_reserve() always succeeds, but there are
cases where it may fail.
Having numerous memblock reservations at early boot where
memblock_can_resize is unset may exhaust the INIT_MEMBLOCK_REGIONS sized
memblock.reserved regions array and an attempt to double this array via
memblock_double_array() will fail and will return -1 to the caller.
When this happens the system crashes anyway, but it's hard to identify
the reason for the crash.
Add a panic message to memblock_double_array() to aid debugging of the
cases when too many regions are reserved before memblock can resize
memblock.reserved array.
Link: https://lore.kernel.org/linux-kernel/20230614131746.3670303-1-songshuaishuai@tinylab.org/
Signed-off-by: Song Shuai <songshuaishuai@tinylab.org>
Link: https://lore.kernel.org/r/20230624032607.921173-1-songshuaishuai@tinylab.org
Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org>
---
mm/memblock.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/mm/memblock.c b/mm/memblock.c
index 913b2520a9a0..0863222af4a4 100644
--- a/mm/memblock.c
+++ b/mm/memblock.c
@@ -424,7 +424,7 @@ static int __init_memblock memblock_double_array(struct memblock_type *type,
* of memory that aren't suitable for allocation
*/
if (!memblock_can_resize)
- return -1;
+ panic("memblock: cannot resize %s array\n", type->name);
/* Calculate new doubled size */
old_size = type->max * sizeof(struct memblock_region);
--
2.42.0