linux-kernel - Re: [PATCH 58/76] idle, x86: Allow off-lined CPU to enter deeper C states

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:	Mon, 2 Apr 2012 14:10:50 -0400
From:	Boris Ostrovsky <boris.ostrovsky@....com>
To:	Tony Luck <tony.luck@...il.com>
CC:	Len Brown <lenb@...nel.org>, <linux-acpi@...r.kernel.org>,
	<linux-pm@...ts.linux-foundation.org>,
	<linux-kernel@...r.kernel.org>, Len Brown <len.brown@...el.com>
Subject: Re: [PATCH 58/76] idle, x86: Allow off-lined CPU to enter deeper
 C states

On 04/02/12 14:02, Tony Luck wrote:
>> x86 halt() causes processor to go to C1 state (which is often not the
>> deepest). But other than that it seems similar to what you are describing.
>
> OK - then Konrad's suggestion of using "safe_halt()" here rather than
> "halt()" would work for ia64.

I originally didn't want to use safe_halt() because the CPU will wake up 
on an unmasked HW interrupt unlike halt(). But I guess we are not 
supposed to get any such interrupts when we are off-lining a CPU so 
safe_halt() should be OK.

Thanks.
-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/