Subject: [net-next:master 226/269] drivers/net/wwan/iosm/iosm_ipc_mux_codec.c:833:21: sparse: sparse: Using plain integer as NULL pointer

From: kernel test robot <[email-masked]>
Date: Fri, 18 Jun 2021 15:26:18 +0800

Hi Loic,

First bad commit (maybe != root cause):

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git master
head:   8fe088bd4fd12f4c8899b51d5bc3daad98767d49
commit: 89212e160b81e778f829b89743570665810e3b13 [226/269] net: wwan: Fix WWAN config symbols
config: i386-allmodconfig (attached as .config)
compiler: gcc-9 (Debian 9.3.0-22) 9.3.0
reproduce:
        # apt-get install sparse
        # sparse version: v0.6.3-341-g8af24329-dirty
        # https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git/commit/?id=89212e160b81e778f829b89743570665810e3b13
        git remote add net-next https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git
        git fetch --no-tags net-next master
        git checkout 89212e160b81e778f829b89743570665810e3b13
        # save the attached .config to linux build tree
        make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' W=1 ARCH=i386 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <[email-masked]>

sparse warnings: (new ones prefixed by >>)
>> drivers/net/wwan/iosm/iosm_ipc_mux_codec.c:833:21: sparse: sparse: Using plain integer as NULL pointer

vim +833 drivers/net/wwan/iosm/iosm_ipc_mux_codec.c

9413491e20e1ab M Chetan Kumar 2021-06-13  814  
9413491e20e1ab M Chetan Kumar 2021-06-13  815  void ipc_mux_ul_encoded_process(struct iosm_mux *ipc_mux, struct sk_buff *skb)
9413491e20e1ab M Chetan Kumar 2021-06-13  816  {
9413491e20e1ab M Chetan Kumar 2021-06-13  817  	struct mux_adgh *adgh;
9413491e20e1ab M Chetan Kumar 2021-06-13  818  	u16 adgh_len;
9413491e20e1ab M Chetan Kumar 2021-06-13  819  
9413491e20e1ab M Chetan Kumar 2021-06-13  820  	adgh = (struct mux_adgh *)skb->data;
9413491e20e1ab M Chetan Kumar 2021-06-13  821  	adgh_len = le16_to_cpu(adgh->length);
9413491e20e1ab M Chetan Kumar 2021-06-13  822  
9413491e20e1ab M Chetan Kumar 2021-06-13  823  	if (adgh->signature == cpu_to_le32(MUX_SIG_ADGH) &&
9413491e20e1ab M Chetan Kumar 2021-06-13  824  	    ipc_mux->ul_flow == MUX_UL)
9413491e20e1ab M Chetan Kumar 2021-06-13  825  		ipc_mux->ul_data_pend_bytes = ipc_mux->ul_data_pend_bytes -
9413491e20e1ab M Chetan Kumar 2021-06-13  826  					      adgh_len;
9413491e20e1ab M Chetan Kumar 2021-06-13  827  
9413491e20e1ab M Chetan Kumar 2021-06-13  828  	if (ipc_mux->ul_flow == MUX_UL)
9413491e20e1ab M Chetan Kumar 2021-06-13  829  		dev_dbg(ipc_mux->dev, "ul_data_pend_bytes: %lld",
9413491e20e1ab M Chetan Kumar 2021-06-13  830  			ipc_mux->ul_data_pend_bytes);
9413491e20e1ab M Chetan Kumar 2021-06-13  831  
9413491e20e1ab M Chetan Kumar 2021-06-13  832  	/* Reset the skb settings. */
9413491e20e1ab M Chetan Kumar 2021-06-13 @833  	skb->tail = 0;
9413491e20e1ab M Chetan Kumar 2021-06-13  834  	skb->len = 0;
9413491e20e1ab M Chetan Kumar 2021-06-13  835  
9413491e20e1ab M Chetan Kumar 2021-06-13  836  	/* Add the consumed ADB to the free list. */
9413491e20e1ab M Chetan Kumar 2021-06-13  837  	skb_queue_tail((&ipc_mux->ul_adb.free_list), skb);
9413491e20e1ab M Chetan Kumar 2021-06-13  838  }
9413491e20e1ab M Chetan Kumar 2021-06-13  839  

:::::: The code at line 833 was first introduced by commit
:::::: 9413491e20e1aba6e471d90c19cc43e523216a4d net: iosm: encode or decode datagram

:::::: TO: M Chetan Kumar <[email-masked]>
:::::: CC: David S. Miller <[email-masked]>

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/[email-masked]