lkml.org 
[lkml]   [2001]   [Sep]   [20]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: pre12 VM doubts and patch

On Thu, 20 Sep 2001, Andrea Arcangeli wrote:
>
> when the page is exclusive we definitely can write to it

NO!

If it is a read-only mapping, we must NOT mark it writable.

The fact is, the page may have been written to earlier, marked read-only
with mprotect(), and the page is dirty but read-only, and swapping it in
MUST NOT markt it writable even if it is our last exclusive copy.

Which we've gotten wrong for a long time, actually. But you #if 0'ed the
fix that happened fairly recently.

Linus

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

\
 
 \ /
  Last update: 2005-03-22 13:03    [W:0.109 / U:2.780 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site