public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Harvey Harrison <harvey.harrison@gmail.com>
To: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>,
	LKML <linux-kernel@vger.kernel.org>,
	Thomas Gleixner <tglx@linutronix.de>, Andi Kleen <ak@suse.de>
Subject: [PATCH] x86: Remove nx_enabled from fault.c
Date: Thu, 24 Jan 2008 20:41:08 -0800	[thread overview]
Message-ID: <1201236068.12822.7.camel@brick> (raw)

On !PAE 32-bit, _PAGE_NX will be 0, making is_prefetch always
return early.  The test is sufficient on PAE as __supported_pte_mask
is updated in the same places as nx_enabled in init_32.c which also
takes disable_nx into account.

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
---
 arch/x86/mm/fault.c |   13 ++++---------
 1 files changed, 4 insertions(+), 9 deletions(-)

diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
index bdf0282..32755eb 100644
--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -92,18 +92,13 @@ static int is_prefetch(struct pt_regs *regs, unsigned long addr,
 	unsigned char *max_instr;
 
 #ifdef CONFIG_X86_32
-# ifdef CONFIG_X86_PAE
-	/* If it was a exec fault on NX page, ignore */
-	if (nx_enabled && (error_code & PF_INSTR))
+	if (!(__supported_pte_mask & _PAGE_NX))
 		return 0;
-# else
-	return 0;
-# endif
-#else /* CONFIG_X86_64 */
+#endif
+
 	/* If it was a exec fault on NX page, ignore */
 	if (error_code & PF_INSTR)
 		return 0;
-#endif
 
 	instr = (unsigned char *)convert_ip_to_linear(current, regs);
 	max_instr = instr + 15;
@@ -468,7 +463,7 @@ static int vmalloc_fault(unsigned long address)
 	pmd_t *pmd, *pmd_ref;
 	pte_t *pte, *pte_ref;
 
-	if (address >= VMALLOC_START && address < VMALLOC_END)
+	if (!(address >= VMALLOC_START && address < VMALLOC_END))
 		return -1;
 
 	/* Copy kernel mappings over when needed. This can also
-- 
1.5.4.rc4.1142.gf5a97




             reply	other threads:[~2008-01-25  4:41 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-01-25  4:41 Harvey Harrison [this message]
2008-01-25 10:14 ` [PATCH] x86: Remove nx_enabled from fault.c Ingo Molnar

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1201236068.12822.7.camel@brick \
    --to=harvey.harrison@gmail.com \
    --cc=ak@suse.de \
    --cc=hpa@zytor.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@elte.hu \
    --cc=tglx@linutronix.de \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox