linux-kernel - Re: [PATCH/RFC] PCI prepare/activate instead of enable to avoid IRQ storm and rogue DMA access

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, 14 Mar 2007 21:56:06 +0000
From:	Russell King <rmk+lkml@....linux.org.uk>
To:	Tejun Heo <htejun@...il.com>
Cc:	gregkh@...e.de, Jeff Garzik <jeff@...zik.org>,
	linux-kernel@...r.kernel.org, linux-pci@...ey.karlin.mff.cuni.cz,
	michal.k.k.piotrowski@...il.com, linux-ide@...r.kernel.org,
	tglx@...utronix.de, shemminger@...ux-foundation.org,
	mlord@...ox.com, linux-pm@...ts.osdl.org
Subject: Re: [PATCH/RFC] PCI prepare/activate instead of enable to avoid IRQ storm and rogue DMA access

On Thu, Mar 15, 2007 at 12:23:02AM +0900, Tejun Heo wrote:
> The problem is that a PCI device can be in any arbitrary when it gets
> enabled and the device has to be enabled for its driver to
> initialize/reset it.  The most common case this causes headache is as
> follows.
> 
> Let's assume there's a device which shares its INTX IRQ line with
> another device and the other one is already initialized.

pci_enable_device() doesn't deal with this; in most PCI setups I've
seen, there is no control at PCI level over whether a device generates
an interrupt on the bus.  Certainly the memory and io command enables
have no effect on the ability of the device to cause an interrupt.

In most cases, only the driver of the device knows how to disable
interrupts on any particular device.

-- 
Russell King
 Linux kernel    2.6 ARM Linux   - http://www.arm.linux.org.uk/
 maintainer of:
-
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/