[BUG] mtdinfo -a: Tries to open NULL pointer for NOR with Eraseblock Regions

[Brian Norris]

On Thu, Aug 4, 2011 at 3:41 PM, Mike Frysinger <vapier at gentoo.org> wrote:
> On Thu, Aug 4, 2011 at 10:46, Brian Norris wrote:
>> On Tue, Jul 26, 2011 at 12:21 AM, Brian Foster wrote:
>>>> It seems that the basic issue we need to solve is how to find the
>>>> correct file devfs/udev path  [...]
>>>
>>>  As an FYI, in our current embedded systems (plural),
>>>  a static /dev is used (no udev, mdev, &tc).  Hence,
>>>  udev (and I assume also, devfs) path may not work
>>>  in such an environment?
>>
>> Now that I think about it, this doesn't seem like a very reliable
>> solution. Too much user-space variability.
>
> when extending mtdinfo, we decided to only support device paths which
> the user gave us.  hence the -m option going away.  libmtd itself has
> /dev/mtd# hardcoded (and imo, that's the only path we should support
> "automatically"), so if we're going to keep the all option, we'll want
> to continue with that (by using the func that libmtd provides rather
> than mtdinfo constructing the string itself).

Hmm, where exactly in mtd-utils/libmtd is the /dev/mtd# hardcoded?
Sorry, but I'm not finding it...

>>>> Also, is "region_info" a potential candidate for exporting via sysfs?
>>>> That would make this support easier to include in libmtd.
>>>
>>>  I don't know if it is exportable or not, but I concur
>>>  this seems like a possible/plausible solution.
>>
>> Even if we do this (which seems like a lot of info), it would only
>> apply to the newest kernels, where mtd-utils are *supposed* to be
>> backwards-compatible if possible, where they can fall back to old
>> methods if needed...
>
> i posted this question recently, and iirc the answer was that it isnt
> currently exported via sysfs, but shouldnt be hard to extend.  just
> have to find someone who wants to do it ;).

"someone who wants to do it" - that's the key for everything, isn't it?

>> Anyway, since I don't have these types of flash readily available, I
>> don't even use these options :) And apparently, one of the biggest
>> contributors for mtd-utils, Mike Frysinger, doesn't use region_info
>> either...
>
> i dont think any of the flashes (parallel nor, spi nor, nand, etc...)
> included region_info.  that's why the func print_region_info() sets up
> a dummy region_info struct that describes the entire flash before
> calling print_region_map().

I don't know much about this, but what's the feature for if no one uses it?

Brian