linux-kernel - Re: [Bugfix v2 4/5] x86/irq: Fix a race condition between vector assigning and cleanup

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:	Wed, 30 Dec 2015 23:50:40 +0100 (CET)
From:	Thomas Gleixner <tglx@...utronix.de>
To:	Jiang Liu <jiang.liu@...ux.intel.com>
cc:	Joe Lawrence <joe.lawrence@...atus.com>,
	Ingo Molnar <mingo@...hat.com>,
	"H. Peter Anvin" <hpa@...or.com>, x86@...nel.org,
	Jeremiah Mahler <jmmahler@...il.com>,
	Borislav Petkov <bp@...en8.de>, andy.shevchenko@...il.com,
	Guenter Roeck <linux@...ck-us.net>,
	linux-kernel@...r.kernel.org
Subject: Re: [Bugfix v2 4/5] x86/irq: Fix a race condition between vector
 assigning and cleanup

On Wed, 23 Dec 2015, Jiang Liu wrote:
>  		/*
> -		 * Check if the irq migration is in progress. If so, we
> -		 * haven't received the cleanup request yet for this irq.
> +		 * Nothing to cleanup if this cpu is not set
> +		 * in the old_domain mask.
>  		 */
> -		if (data->move_in_progress)
> -			goto unlock;
> -
> -		if (vector == data->cfg.vector &&
> -		    cpumask_test_cpu(me, data->domain))

Actually we cannot remove this check either. If the vector changed from 100 to
80, then we cleanup vector 80 which is the active vector and the old one
remains stale. Not pretty, right?

I'll send out a fine granular series tomorrow when my brain is more awake.

Thanks,

	tglx
--
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/