diff options
| author | H. Peter Anvin <hpa@zytor.com> | 2009-11-13 15:28:16 -0800 |
|---|---|---|
| committer | H. Peter Anvin <hpa@zytor.com> | 2009-11-16 13:44:59 -0800 |
| commit | 4763ed4d45522b876c97e1f7f4b659d211f75571 (patch) | |
| tree | ae053500de9f1c374e4b7f34d8f21d45a5b961d2 /arch/x86/mm/init.c | |
| parent | 583140afb989f24d115e80be5c91e503b58ccfc0 (diff) | |
x86, mm: Clean up and simplify NX enablement
The 32- and 64-bit code used very different mechanisms for enabling
NX, but even the 32-bit code was enabling NX in head_32.S if it is
available. Furthermore, we had a bewildering collection of tests for
the available of NX.
This patch:
a) merges the 32-bit set_nx() and the 64-bit check_efer() function
into a single x86_configure_nx() function. EFER control is left
to the head code.
b) eliminates the nx_enabled variable entirely. Things that need to
test for NX enablement can verify __supported_pte_mask directly,
and cpu_has_nx gives the supported status of NX.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Vegard Nossum <vegardno@ifi.uio.no>
Cc: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Chris Wright <chrisw@sous-sol.org>
LKML-Reference: <1258154897-6770-5-git-send-email-hpa@zytor.com>
Acked-by: Kees Cook <kees.cook@canonical.com>
Diffstat (limited to 'arch/x86/mm/init.c')
| -rw-r--r-- | arch/x86/mm/init.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c index 73ffd5536f6..27ec2c23fd4 100644 --- a/arch/x86/mm/init.c +++ b/arch/x86/mm/init.c @@ -146,8 +146,8 @@ unsigned long __init_refok init_memory_mapping(unsigned long start, use_gbpages = direct_gbpages; #endif - set_nx(); - if (nx_enabled) + /* XXX: replace this with Kees' improved messages */ + if (__supported_pte_mask & _PAGE_NX) printk(KERN_INFO "NX (Execute Disable) protection: active\n"); /* Enable PSE if available */ |