The driver may sleep under a spin lock, the function call path is:
isdn_ppp_mp_receive (acquire the lock)
isdn_ppp_mp_reassembly
isdn_ppp_push_higher
isdn_ppp_decompress
isdn_ppp_ccp_reset_trans
isdn_ppp_ccp_reset_alloc_state
kzalloc(GFP_KERNEL) --> may sleep
To fixed it, the "GFP_KERNEL" is replaced with "GFP_ATOMIC".
Signed-off-by: Jia-Ju Bai <baijiaju1990@163.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
e8f4ae8543