linux-kernel - Re: [PATCH 2/6] x86: apic

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: <20080816201235.GB7182@lenovo>
Date:	Sun, 17 Aug 2008 00:12:35 +0400
From:	Cyrill Gorcunov <gorcunov@...il.com>
To:	Arjan van de Ven <arjan@...radead.org>
Cc:	"Maciej W. Rozycki" <macro@...ux-mips.org>, mingo@...e.hu,
	hpa@...or.com, tglx@...utronix.de, linux-kernel@...r.kernel.org
Subject: Re: [PATCH 2/6] x86: apic - unify lapic_resume

[Arjan van de Ven - Sat, Aug 16, 2008 at 01:00:08PM -0700]
| On Sat, 16 Aug 2008 20:52:07 +0100 (BST)
| "Maciej W. Rozycki" <macro@...ux-mips.org> wrote:
| 
| > On Sat, 16 Aug 2008, Cyrill Gorcunov wrote:
| > 
| > > +#ifdef CONFIG_X86_64
| > > +	if (x2apic)
| > > +		enable_x2apic();
| > > +	else
| > > +#endif
| > 
| >  Hmm, x86-64 hardware can run a 32-bit kernel, so it might be a good
| > idea to take the opportunity of the merge and extend x2APIC support
| > to the 32-bit configuration too.  It should be mostly a mechanical
| > change.  Just a suggestion though -- feel free to ignore if you'd
| > rather not dive into it. ;)
| 
| it's not like you can/want to go over 128 cpus on a 32 bit kernel
| though..
| -- 
| If you want to reach me at my work email, use arjan@...ux.intel.com
| For development, discussion and tips for power savings, 
| visit http://www.lesswatts.org
| 

Arjan,

it seems this limit is not APIC related since iirc 82489DX allows
to address 2^14 bits, x2APIC - more then 128 entities too. So I suspect
it somehow cpu bitmap related. Am I wrong (I didn't _check_ the code)?

		- Cyrill -
--
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/