lkml.org 
[lkml]   [2000]   [Oct]   [26]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: Kernel OOPS on boot
"Richard B. Johnson" wrote:
> Stand-alone, it can't do anything useful. However, if it generates
> a page-fault due to the read or write, the page-fault handler could
> do "something". Currently, the fault it fatal, probably because
> the passed pointer is invalid.

The write-protect test code is a red herring. This was caused by GCC
2.7.x trashing kernel_module, causing the page fault handler to fail
when trying to find an exception handler. This code is intentionally
trying to generate a page fault, to test if the processor allows writes
to a write-protected page while in ring 0. Some 386's and 486's won't
generate a page fault in this case, and we need to work around this or
else security problems arise.

--

Brian Gerst
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 12:45    [W:0.056 / U:0.064 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site