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, 28 Jul 2008 21:53:24 +0200
From:	Andi Kleen <andi@...stfloor.org>
To:	Thomas Gleixner <tglx@...utronix.de>
Cc:	Andi Kleen <andi@...stfloor.org>,
	Linus Torvalds <torvalds@...ux-foundation.org>,
	Andrew Morton <akpm@...ux-foundation.org>,
	LKML <linux-kernel@...r.kernel.org>, Ingo Molnar <mingo@...e.hu>,
	Dhaval Giani <dhaval@...ux.vnet.ibm.com>,
	Venkatesch Pallipadi <venkatesh.pallipadi@...el.com>,
	Len Brown <lenb@...nel.org>
Subject: Re: [PATCH] ACPI/CPUIDLE: prevent setting pm_idle to NULL

> The problem here is that the acpi/cpuidle code can be in a state where
> the _save/old variables _ARE_ NULL because they had not been
> initialized with the original pm_idle before the module is removed or
> the cst state changes. So all we have to do is to prevent pm_idle to
> be set to NULL.

It still seems wrong to me to fall back to the cpuidle idle function
instead of the earlier idle function just because cpuidle was loaded
in a weird way. 

But yes mwait_idle could be set up later after the saving state.
I suggested default_idle because it is safe, but yes it is probably
not the optimal choice.

Perhaps to solve this cleanly we really need to go to a hierarchy
of idle functions registered with priority instead of this fragile
pointer saving/restoring. 

-Andi
--
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/

Powered by blists - more mailing lists