2018-07-23 09:13:32

by Jia-Ju Bai

[permalink] [raw]
Subject: [PATCH] firmware: memmap: Replace GFP_ATOMIC with GFP_KERNEL in firmware_map_add_hotplug()

firmware_map_add_hotplug() is only called by add_memory_resource(),
which is never called in atomic context.

firmware_map_add_hotplug() calls kzalloc() with GFP_ATOMIC,
which is not necessary.
GFP_ATOMIC can be replaced with GFP_KERNEL.

This is found by a static analysis tool named DCNS written by myself.
I also manually check the kernel code before reporting it.

Signed-off-by: Jia-Ju Bai <[email protected]>
---
drivers/firmware/memmap.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/firmware/memmap.c b/drivers/firmware/memmap.c
index 5de3ed29282c..598eb0511097 100644
--- a/drivers/firmware/memmap.c
+++ b/drivers/firmware/memmap.c
@@ -297,7 +297,7 @@ int __meminit firmware_map_add_hotplug(u64 start, u64 end, const char *type)

entry = firmware_map_find_entry_bootmem(start, end - 1, type);
if (!entry) {
- entry = kzalloc(sizeof(struct firmware_map_entry), GFP_ATOMIC);
+ entry = kzalloc(sizeof(struct firmware_map_entry), GFP_KERNEL);
if (!entry)
return -ENOMEM;
} else {
--
2.17.0