From: Andrew Morton <[email protected]>
Date: Sun, 12 Feb 2006 18:13:12 -0800
> We have a page which has no ->mapping, but lo, it's mmapped by userspace
> and can be MAP_SHARED between different CPUs and processes.
>
> Yes, I suspect it'll do the wrong thing in unpleasantly subtle ways.
>
> (cc's davem and runs away).
The ->mapping check is there essentially to hit user mapped pages that
would be modified by the kernel using kernel space memory accesses
other than those done by copy_user_page() and clear_user_page() (and
their brothers copy_user_highpage() and clear_user_highpage() which
just call the former directly on a non-HIGHPAGE platform like
sparc64).
Hugepages actually have no D-cache aliasing issues by definition on
sparc64 because the smallest possible hugepage size is 64K which is
larger than the D-cache aliasing factor (which is 16K).
-
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/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
