linux-kernel - Re: PATCH: (v3) Allow over-ride of smp_found

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]

Message-ID: <498C9D1C.2060302@candelatech.com>
Date:	Fri, 06 Feb 2009 12:27:08 -0800
From:	Ben Greear <greearb@...delatech.com>
To:	Yinghai Lu <yinghai@...nel.org>
CC:	Randy Dunlap <randy.dunlap@...cle.com>,
	Ingo Molnar <mingo@...e.hu>, "H. Peter Anvin" <hpa@...or.com>,
	Thomas Gleixner <tglx@...utronix.de>,
	"Maciej W. Rozycki" <macro@...ux-mips.org>,
	linux-kernel <linux-kernel@...r.kernel.org>, len.brown@...el.com
Subject: Re: PATCH:  (v3) Allow over-ride of smp_found_cfg with kernel cmd-line
 option.

Yinghai Lu wrote:

>>> +                "WARNING: No ACPI-table found in the MADT\n");
>> 		                APIC table
>>
> 
> APIC-table == MADT
> 
> could just use
> 
> WARNING: No APIC-table found

Ok, here's another attempt.  NOTE:  With another patch that Len sent me,
this work-around seems no longer required for *my* system.  This patch may
still help others, however...


An updated patch is attached.  It's also inline below, but I'm sure the
inline version is white-space corrupted.

Do not disable mptable parsing just because there is no ACPI table
in the MADT table.  This effectively backs out changeset
7b37b5fd9ba32c0c5afc3537eed7e7466f2173e2

Signed-Off-By:  Ben Greear<greearb@...delatech.com>

diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c
index d37593c..6940fb2 100644
--- a/arch/x86/kernel/acpi/boot.c
+++ b/arch/x86/kernel/acpi/boot.c
@@ -1379,12 +1379,14 @@ static void __init acpi_process_madt(void)
   		 * ACPI found no MADT, and so ACPI wants UP PIC mode.
   		 * In the event an MPS table was found, forget it.
   		 * Boot with "acpi=off" to use MPS on such a system.
+		 *
+		 * NOTE:  This assumption seems wrong in at least some cases, perhaps
+		 *  when ACPI is off in the BIOS.  Changing to a warning without
+		 *  setting smp_found_config to zero.
   		 */
-		if (smp_found_config) {
+		if (smp_found_config)
  			printk(KERN_WARNING PREFIX
-				"No APIC-table, disabling MPS\n");
-			smp_found_config = 0;
-		}
+			       "WARNING: No APIC-table found.\n");
  	}

  	/*


-- 
Ben Greear <greearb@...delatech.com>
Candela Technologies Inc  http://www.candelatech.com


View attachment "madt_patch2.txt" of type "text/plain" (815 bytes)