Re: [PATCH v3 1/1] arm64: ptrace: fix hw_break_set() to set addr and ctrl together

[kernel test robot <lkp@intel.com>]

Hi Bill,

kernel test robot noticed the following build warnings:

[auto build test WARNING on arm64/for-next/core]
[also build test WARNING on linus/master v6.18-rc1 next-20251017]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Bill-Tsui/arm64-ptrace-fix-hw_break_set-to-set-addr-and-ctrl-together/20251016-235711
base:   https://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-next/core
patch link:    https://lore.kernel.org/r/20251016154401.35799-2-b10902118%40ntu.edu.tw
patch subject: [PATCH v3 1/1] arm64: ptrace: fix hw_break_set() to set addr and ctrl together
config: arm64-randconfig-r113-20251018 (https://download.01.org/0day-ci/archive/20251018/202510181547.dI5kyPuT-lkp@intel.com/config)
compiler: aarch64-linux-gcc (GCC) 8.5.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20251018/202510181547.dI5kyPuT-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202510181547.dI5kyPuT-lkp@intel.com/

All warnings (new ones prefixed by >>):

>> arch/arm64/kernel/ptrace.c:449:12: warning: 'ptrace_hbp_set_addr' defined but not used [-Wunused-function]
    static int ptrace_hbp_set_addr(unsigned int note_type,
               ^~~~~~~~~~~~~~~~~~~
>> arch/arm64/kernel/ptrace.c:424:12: warning: 'ptrace_hbp_set_ctrl' defined but not used [-Wunused-function]
    static int ptrace_hbp_set_ctrl(unsigned int note_type,
               ^~~~~~~~~~~~~~~~~~~


vim +/ptrace_hbp_set_addr +449 arch/arm64/kernel/ptrace.c

478fcb2cdb2351 Will Deacon 2012-03-05  423  
478fcb2cdb2351 Will Deacon 2012-03-05 @424  static int ptrace_hbp_set_ctrl(unsigned int note_type,
478fcb2cdb2351 Will Deacon 2012-03-05  425  			       struct task_struct *tsk,
478fcb2cdb2351 Will Deacon 2012-03-05  426  			       unsigned long idx,
478fcb2cdb2351 Will Deacon 2012-03-05  427  			       u32 uctrl)
478fcb2cdb2351 Will Deacon 2012-03-05  428  {
478fcb2cdb2351 Will Deacon 2012-03-05  429  	int err;
478fcb2cdb2351 Will Deacon 2012-03-05  430  	struct perf_event *bp;
478fcb2cdb2351 Will Deacon 2012-03-05  431  	struct perf_event_attr attr;
478fcb2cdb2351 Will Deacon 2012-03-05  432  	struct arch_hw_breakpoint_ctrl ctrl;
478fcb2cdb2351 Will Deacon 2012-03-05  433  
478fcb2cdb2351 Will Deacon 2012-03-05  434  	bp = ptrace_hbp_get_initialised_bp(note_type, tsk, idx);
478fcb2cdb2351 Will Deacon 2012-03-05  435  	if (IS_ERR(bp)) {
478fcb2cdb2351 Will Deacon 2012-03-05  436  		err = PTR_ERR(bp);
478fcb2cdb2351 Will Deacon 2012-03-05  437  		return err;
478fcb2cdb2351 Will Deacon 2012-03-05  438  	}
478fcb2cdb2351 Will Deacon 2012-03-05  439  
478fcb2cdb2351 Will Deacon 2012-03-05  440  	attr = bp->attr;
478fcb2cdb2351 Will Deacon 2012-03-05  441  	decode_ctrl_reg(uctrl, &ctrl);
478fcb2cdb2351 Will Deacon 2012-03-05  442  	err = ptrace_hbp_fill_attr_ctrl(note_type, ctrl, &attr);
478fcb2cdb2351 Will Deacon 2012-03-05  443  	if (err)
478fcb2cdb2351 Will Deacon 2012-03-05  444  		return err;
478fcb2cdb2351 Will Deacon 2012-03-05  445  
478fcb2cdb2351 Will Deacon 2012-03-05  446  	return modify_user_hw_breakpoint(bp, &attr);
478fcb2cdb2351 Will Deacon 2012-03-05  447  }
478fcb2cdb2351 Will Deacon 2012-03-05  448  
478fcb2cdb2351 Will Deacon 2012-03-05 @449  static int ptrace_hbp_set_addr(unsigned int note_type,
478fcb2cdb2351 Will Deacon 2012-03-05  450  			       struct task_struct *tsk,
478fcb2cdb2351 Will Deacon 2012-03-05  451  			       unsigned long idx,
478fcb2cdb2351 Will Deacon 2012-03-05  452  			       u64 addr)
478fcb2cdb2351 Will Deacon 2012-03-05  453  {
478fcb2cdb2351 Will Deacon 2012-03-05  454  	int err;
478fcb2cdb2351 Will Deacon 2012-03-05  455  	struct perf_event *bp;
478fcb2cdb2351 Will Deacon 2012-03-05  456  	struct perf_event_attr attr;
478fcb2cdb2351 Will Deacon 2012-03-05  457  
478fcb2cdb2351 Will Deacon 2012-03-05  458  	bp = ptrace_hbp_get_initialised_bp(note_type, tsk, idx);
478fcb2cdb2351 Will Deacon 2012-03-05  459  	if (IS_ERR(bp)) {
478fcb2cdb2351 Will Deacon 2012-03-05  460  		err = PTR_ERR(bp);
478fcb2cdb2351 Will Deacon 2012-03-05  461  		return err;
478fcb2cdb2351 Will Deacon 2012-03-05  462  	}
478fcb2cdb2351 Will Deacon 2012-03-05  463  
478fcb2cdb2351 Will Deacon 2012-03-05  464  	attr = bp->attr;
478fcb2cdb2351 Will Deacon 2012-03-05  465  	attr.bp_addr = addr;
478fcb2cdb2351 Will Deacon 2012-03-05  466  	err = modify_user_hw_breakpoint(bp, &attr);
478fcb2cdb2351 Will Deacon 2012-03-05  467  	return err;
478fcb2cdb2351 Will Deacon 2012-03-05  468  }
478fcb2cdb2351 Will Deacon 2012-03-05  469  

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