Re: [PATCH v3 3/3] drivers/base/node.c: use bin_attribute to avoid buff overflow

[tiantao (H)]

在 2021/6/3 17:53, Andy Shevchenko 写道:
> On Thu, Jun 03, 2021 at 05:22:42PM +0800, Tian Tao wrote:
> > Reading sys/devices/system/cpu/cpuX/nodeX/ returns cpumap and cpulist.
> > However, the size of this file is limited to PAGE_SIZE because of the
> > limitation for sysfs attribute. so we use bin_attribute instead of
> > attribute to avoid NR_CPUS too big to cause buff overflow.
> ...
>
> >   }
> >   
> > -static DEVICE_ATTR_RO(cpumap);
> >   
> > -static inline ssize_t cpulist_show(struct device *dev,
> > -				   struct device_attribute *attr,
> > -				   char *buf)
> > +static BIN_ATTR_RO(cpumap, 0);
> So, you will have 2 blank lines in a row after this. Why one is not enough?
> Same question for other similar cases, if any.

 I can delete the line 55. this is the only problem, are there any 
other problems?

47 static inline ssize_t cpumap_read(struct file *file, struct kobject 
*kobj,

  48                                   struct bin_attribute *attr, char 
*buf,
  49                                   loff_t off, size_t count)
  50 {
  51         struct device *dev = kobj_to_dev(kobj);
  52
  53         return node_read_cpumap(dev, false, buf, off, count);
  54 }
  55
  56
  57 static BIN_ATTR_RO(cpumap, 0);
  58
  59 static inline ssize_t cpulist_read(struct file *file, struct 
kobject *kobj,
  60                                    struct bin_attribute *attr, 
char *buf,
  61                                    loff_t off, size_t count)
  62 {
  63         struct device *dev = kobj_to_dev(kobj);
  64
  65         return node_read_cpumap(dev, true, buf, off, count);
  66 }
  67
  68 static BIN_ATTR_RO(cpulist, 0);

>