[tip:WIP.sched/core 11/11] drivers/scsi/ufs/ufshcd.c:2413:17: warning: 'tag' may be used uninitialized in this function

[kbuild test robot]

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git WIP.sched/core
head:   b7c6a9d358c54f2d57d3df384d42083817e05028
commit: b7c6a9d358c54f2d57d3df384d42083817e05028 [11/11] sched/wait: Introduce new, more compact wait_event*() primitives
config: ia64-allmodconfig (attached as .config)
compiler: ia64-linux-gcc (GCC) 6.2.0
reproduce:
        wget https://git.kernel.org/cgit/linux/kernel/git/wfg/lkp-tests.git/plain/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        git checkout b7c6a9d358c54f2d57d3df384d42083817e05028
        # save the attached .config to linux build tree
        make.cross ARCH=ia64 

Note: it may well be a FALSE warning. FWIW you are at least aware of it now.
http://gcc.gnu.org/wiki/Better_Uninitialized_Warnings

All warnings (new ones prefixed by >>):

   drivers/scsi/ufs/ufshcd.c: In function 'ufshcd_exec_dev_cmd':
>> drivers/scsi/ufs/ufshcd.c:2413:17: warning: 'tag' may be used uninitialized in this function [-Wmaybe-uninitialized]
     lrbp->task_tag = tag;
     ~~~~~~~~~~~~~~~^~~~~
   drivers/scsi/ufs/ufshcd.c:2589:6: note: 'tag' was declared here
     int tag;
         ^~~
   drivers/scsi/ufs/ufshcd.c: In function 'ufshcd_issue_tm_cmd':
>> drivers/scsi/ufs/ufshcd.c:5404:11: warning: 'free_slot' may be used uninitialized in this function [-Wmaybe-uninitialized]
     task_tag = hba->nutrs + free_slot;
     ~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~

vim +/tag +2413 drivers/scsi/ufs/ufshcd.c

7a3e97b0 Santosh Yaraganavi 2012-02-29  2397  	spin_lock_irqsave(hba->host->host_lock, flags);
0e675efa Kiwoong Kim        2016-11-10  2398  	ufshcd_vops_setup_xfer_req(hba, tag, (lrbp->cmd ? true : false));
7a3e97b0 Santosh Yaraganavi 2012-02-29  2399  	ufshcd_send_command(hba, tag);
3441da7d Sujit Reddy Thumma 2014-05-26  2400  out_unlock:
7a3e97b0 Santosh Yaraganavi 2012-02-29  2401  	spin_unlock_irqrestore(hba->host->host_lock, flags);
7a3e97b0 Santosh Yaraganavi 2012-02-29  2402  out:
a3cd5ec5 Subhash Jadavani   2017-02-03  2403  	up_read(&hba->clk_scaling_lock);
7a3e97b0 Santosh Yaraganavi 2012-02-29  2404  	return err;
7a3e97b0 Santosh Yaraganavi 2012-02-29  2405  }
7a3e97b0 Santosh Yaraganavi 2012-02-29  2406  
5a0b0cb9 Sujit Reddy Thumma 2013-07-30  2407  static int ufshcd_compose_dev_cmd(struct ufs_hba *hba,
5a0b0cb9 Sujit Reddy Thumma 2013-07-30  2408  		struct ufshcd_lrb *lrbp, enum dev_cmd_type cmd_type, int tag)
5a0b0cb9 Sujit Reddy Thumma 2013-07-30  2409  {
5a0b0cb9 Sujit Reddy Thumma 2013-07-30  2410  	lrbp->cmd = NULL;
5a0b0cb9 Sujit Reddy Thumma 2013-07-30  2411  	lrbp->sense_bufflen = 0;
5a0b0cb9 Sujit Reddy Thumma 2013-07-30  2412  	lrbp->sense_buffer = NULL;
5a0b0cb9 Sujit Reddy Thumma 2013-07-30 @2413  	lrbp->task_tag = tag;
5a0b0cb9 Sujit Reddy Thumma 2013-07-30  2414  	lrbp->lun = 0; /* device management cmd is not specific to any LUN */
5a0b0cb9 Sujit Reddy Thumma 2013-07-30  2415  	lrbp->intr_cmd = true; /* No interrupt aggregation */
5a0b0cb9 Sujit Reddy Thumma 2013-07-30  2416  	hba->dev_cmd.type = cmd_type;
5a0b0cb9 Sujit Reddy Thumma 2013-07-30  2417  
300bb13f Joao Pinto         2016-05-11  2418  	return ufshcd_comp_devman_upiu(hba, lrbp);
5a0b0cb9 Sujit Reddy Thumma 2013-07-30  2419  }
5a0b0cb9 Sujit Reddy Thumma 2013-07-30  2420  
5a0b0cb9 Sujit Reddy Thumma 2013-07-30  2421  static int

:::::: The code at line 2413 was first introduced by commit
:::::: 5a0b0cb9bee767ef10ff9ce2fb4141af06416288 [SCSI] ufs: Add support for sending NOP OUT UPIU

:::::: TO: Sujit Reddy Thumma <sthumma@xxxxxxxxxxxxxx>
:::::: CC: James Bottomley <JBottomley@xxxxxxxxxxxxx>

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