Re: [bug] ata subsystem related crash with latest -git

Linus Torvalds
2007-10-18T04:21:22Z

On Thu, 18 Oct 2007, Mark Lord wrote:
>
> Oh.. so this bug is supposed to only bite with DEBUG_PAGEALLOC=y ??

Yeah, this particular one really should only bite you with
DEBUG_PAGEALLOC.

The SG code potentially _derefences_ a field past the end of the SG array,
but it should be a read, and the result should never be used (it's used to
calculate the pointer to past the end of the queue, so if it's used,
there's another bug lurking).

> Then something else is broken, perhaps. I just saw a long traceback
> scroll off the top of the screen, with lots of bio_* functions in the
> list and assumed it was the same bug.
>
> Mmm.. I'll get out the camera and try it again now..

Please do. I wouldn't be surprised if it's also related to the SG changes,
but I don't think it's the exact particular bug that Ingo saw.

Linus