linux-kernel - [PATCH 7/8] x86/mrst: add nop functions to x86

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Fri, 14 May 2010 14:41:20 -0700
From:	Jacob Pan <jacob.jun.pan@...ux.intel.com>
To:	LKML <linux-kernel@...r.kernel.org>,
	"H. Peter Anvin" <hpa@...or.com>, Ingo Molnar <mingo@...e.hu>,
	Thomas Gleixner <tglx@...utronix.de>,
	Alan Cox <alan@...ux.intel.com>,
	Arjan van de Ven <arjan@...ux.intel.com>
Cc:	Jacob Pan <jacob.jun.pan@...ux.intel.com>
Subject: [PATCH 7/8] x86/mrst: add nop functions to x86_init mpparse functions

Moorestown does not have BIOS provided MP tables, we can save some time
by avoiding scaning of these tables. e.g.
[    0.000000] Scan SMP from c0000000 for 1024 bytes.
[    0.000000] Scan SMP from c009fc00 for 1024 bytes.
[    0.000000] Scan SMP from c00f0000 for 65536 bytes.
[    0.000000] Scan SMP from c00bfff0 for 1024 bytes.

Searching EBDA with the base at 0x40E will also result in random pointer
deferencing within 1MB. This can be a problem in Lincroft if the pointer
hits VGA area and VGA mode is not enabled.

Signed-off-by: Jacob Pan <jacob.jun.pan@...ux.intel.com>
---
 arch/x86/kernel/mrst.c |    5 +++++
 1 files changed, 5 insertions(+), 0 deletions(-)

diff --git a/arch/x86/kernel/mrst.c b/arch/x86/kernel/mrst.c
index 83c23d6..9b62d32 100644
--- a/arch/x86/kernel/mrst.c
+++ b/arch/x86/kernel/mrst.c
@@ -311,4 +311,9 @@ void __init x86_mrst_early_setup(void)
 	x86_init.pci.fixup_irqs = x86_init_noop;
 
 	legacy_pic = &null_legacy_pic;
+
+	/* Avoid searching for BIOS MP tables */
+	x86_init.mpparse.find_smp_config = x86_init_noop;
+	x86_init.mpparse.get_smp_config = x86_init_uint_noop;
+
 }
-- 
1.6.3.3

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