linux-kernel - Re: nr_cpu_ids incorrect on AMD Quad-Core Opteron 8380

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:	Tue, 2 Feb 2010 08:07:51 +0100
From:	Borislav Petkov <petkovbb@...glemail.com>
To:	zhiyi <zhuang@...otago.ac.nz>
Cc:	linux-kernel@...r.kernel.org, Zhiyi Huang <hzy@...otago.ac.nz>,
	jkmair@...otago.ac.nz
Subject: Re: nr_cpu_ids incorrect on AMD Quad-Core Opteron 8380

On Tue, Feb 02, 2010 at 01:49:06PM +1300, zhiyi wrote:
> The dmesg relevant to nr_cpu_ids of the quad socket is:
> 
> [    0.000000] NR_CPUS:64 nr_cpumask_bits:64 nr_cpu_ids:32 nr_node_ids:4
> 

No, this is not the relevant info. I was actually looking for the MADT ACPI
table and whether there are disabled entries like so:

[    0.000000] ACPI: LAPIC (acpi-id[0x03] lapic-id[0x02] enabled)
[    0.000000] ACPI: LAPIC (acpi-id[0x04] lapic-id[0x03] enabled)
[    0.000000] ACPI: LAPIC (acpi-id[0x05] lapic-id[0x84] disabled)
[    0.000000] ACPI: LAPIC (acpi-id[0x06] lapic-id[0x85] disabled)

because if there are, nr_cpu_ids will include those when you don't boot
with "possible_cpus=N".

Anyhow, you can read this for more info: http://www.pubbs.net/kernel/200912/64310/

-- 
Regards/Gruss,
    Boris.
--
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/