Re: [GIT PULL] perf fixes

[Linus Torvalds <torvalds@linux-foundation.org>]

On Mon, 22 Feb 2010, Ingo Molnar wrote:
> 
> The reason i'm sending them post -rc8 is the fix for the Wine breakage from 
> Frederic, which would be nice to see resolved in -final.

Umm. That commit seems to be crap.

Yes, it was wrong to not allow a NULL address breakpoint. But if you call 
kallsyms_lookup_name(), you should check the "I couldn't find it" end 
result for _that_ case, and 0 is the correct check there.

So the code _should_ do something like

	if (info->name) {
		info->address = kallsyms_lookup_name(info->name);
		if (!info->address)
			return -EINVAL;
	}

and that would correctly handle both the NULL original address _and_ the 
name lookup failure.

Also, note how I removed the totally bogus cast.

Anyway, I pulled, but I really wish somebody had thought through those 
cases. Somebody who knows the code better than I do (maybe there is an 
error check later for "if (info->name && !info->address)", but I didn't 
see one in a quick grep).

		Linus