On Wed, 3 Oct 2007, Ingo Molnar wrote: > > hm, i just triggered the procfs crash below with -rc9 on a testbox.
You have a terminally buggy piece of shit compiler. Lookie here: - the bug happens on this: char c = *p++; - which has been compiled into 8b 3a mov (%edx),%edi which is a *word* access. - the pointer is at the end of a page (very much on purpose): edx: f2a3fffe - and as a result you get an exception on the *next* page: BUG: unable to handle kernel paging request at virtual address f2a40000 and btw, there is no question what-so-ever about whether your compiler might be doing a legal optimization - the compiler really is wrong, and is total shit. You need to make a gcc bug-report. Because this is not a question of "the standard is ambiguous", this is a question of "the compiler turned good code into code that could SIGSEGV in user space too, if 'malloc()' happened to return a pointer at the end of an allocation". Linus - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/