linux-kernel - [PATCH] Make Intel 8-way Xeons boot again

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-next>] [day] [month] [year] [list]

Message-ID: <20100109101038.GA17555@in.ibm.com>
Date:	Sat, 9 Jan 2010 15:40:38 +0530
From:	Ananth N Mavinakayanahalli <ananth@...ibm.com>
To:	suresh.b.siddha@...el.com,
	Linus Torvalds <torvalds@...ux-foundation.org>
Cc:	yinghai@...nel.org, Ingo Molnar <mingo@...e.hu>,
	lkml <linux-kernel@...r.kernel.org>, stable@...nel.org
Subject: [PATCH] Make Intel 8-way Xeons boot again

On an 8-way system with Intel Xeon X7350 CPUs, booting 2.6.32 or newer
kernels fails at:

...
CPU0: Intel(R) Xeon(R) CPU           X7350  @ 2.93GHz stepping 0b
Booting Node   0, Processors  #1 #2 #3 #4 #5 #6 #7 Ok.
Brought up 8 CPUs
Total of 8 processors activated (46906.05 BogoMIPS).

Git bisect showed 2fbd07a5f as the offending commit.

With the patch below, I am able to boot the latest Linus' git tree on
the machine. If this patch is correct, it needs to get into the stable
tree too.

Signed-off-by: Ananth N Mavinakayanahalli <ananth@...ibm.com>
---
Index: linux-2.6/arch/x86/kernel/apic/probe_64.c
===================================================================
--- linux-2.6.orig/arch/x86/kernel/apic/probe_64.c	2010-01-09 14:54:29.000000000 +0530
+++ linux-2.6/arch/x86/kernel/apic/probe_64.c	2010-01-09 14:57:53.000000000 +0530
@@ -70,7 +70,7 @@
 	if (apic == &apic_flat) {
 		switch (boot_cpu_data.x86_vendor) {
 		case X86_VENDOR_INTEL:
-			if (num_processors > 8)
+			if (num_processors >= 8)
 				apic = &apic_physflat;
 			break;
 		case X86_VENDOR_AMD:
--
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/