Re: udev problem (and fix) for /dev/mtdblock*

[David Brownell <david-b@pacbell.net>]

On Monday 23 March 2009, Kay Sievers wrote:
> On Mon, Mar 23, 2009 at 21:39, David Brownell <david-b@pacbell.net> wrote:
> > On Monday 23 March 2009, Kay Sievers wrote:
> >> > OTP data in lot of the NAND chips I have here exceeds the sysfs 4KB
> >> > binary file limit; 20KB commonly, 128KB for OneNand.
> >>
> >> There is no such limit for binary sysfs files. We have many large file
> >> there, which map such sizes.
> >
> > Odd, just the other day I created one with actual size of 8KB.
> > But "ls -l" showed 4K.
> 
> There are larger files:

Could be.  But still ... I set the size of the attribute to 8K,
but "ls" reported only 4K.


> > Something seems odd with binary sysfs files in general.  I've
> > observed something zapping size down to zero after userspace
> > did some oddball reads ... of the "past EOF" variety, ISTR.
> 
> Hmm, never seen such a thing, but the logic is implemented per-file,
> so it might be something that should be fixed in the driver that
> created the file.

All those drivers do is respond to read/write calls, and set
the size statically.


I've seen both those failures in multiple drivers, FWIW.

- Dave