H. Peter Anvin wrote: > Sticking kernel mode values in those fields would add no value, except > as a poison (since %ss == KERNEL_DS and would cause a #GP(0) if it ever > reached IRET.) If anything, those fields should be pushed as zero or > some other poison bits. That would be slightly better than what's there > now, which is whatever garbage happens to be on the stack. Pushing the > kernel SS:ESP is just plain wrong (not to mention that the way you do it > doesn't even produce the right value for ESP -- you'd have to save away > ESP before you push SS.)
That's true. The xss and esp fields of the pt_regs struct always contain either garbage (for interrupts occuring while in kernel mode) or user-mode values (for interrupts occuring while in user mode). So, filling these fields with kernel-mode values indeed doesn't make much sense. Allocating space on the stack and poisoning those values would make sense, though, so I will modify the patch accordingly and resend it. Thank you for your feedback! - Philipp Kohlbecher - 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/
