Re: [PATCH bpf-next] bpf: use kvmalloc in map_lookup_elem

Use kvmalloc/kvfree for temporary value when looking up a map.
kmalloc might not be sufficient for percpu maps where the value is big.

Can be reproduced with netcnt test on qemu with "-smp 255".

Signed-off-by: Stanislav Fomichev <redacted>
---
  kernel/bpf/syscall.c | 4 ++--
  1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 9a2068e39d23..ae0b1c1c8ece 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c

@@ -1076,7 +1076,7 @@ static int map_lookup_elem(union bpf_attr *attr)
  	value_size = bpf_map_value_size(map);
  
  	err = -ENOMEM;
-	value = kmalloc(value_size, GFP_USER | __GFP_NOWARN);
+	value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN);
  	if (!value)
  		goto free_key;