linux-kernel - Re: [PATCH 1/1] ahci: Do not receive interrupts sent by dummy ports

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: <20140417170641.GR15326@htj.dyndns.org>
Date:	Thu, 17 Apr 2014 13:06:41 -0400
From:	Tejun Heo <tj@...nel.org>
To:	Alexander Gordeev <agordeev@...hat.com>
Cc:	linux-kernel@...r.kernel.org, David Milburn <dmilburn@...hat.com>,
	linux-ide@...r.kernel.org
Subject: Re: [PATCH 1/1] ahci: Do not receive interrupts sent by dummy ports

On Thu, Apr 17, 2014 at 06:06:15PM +0200, Alexander Gordeev wrote:
> In multiple MSI mode all AHCI ports (including dummy) get
> assigned separate MSI vectors and (as result of execution
> pci_enable_msi_exact() function) separate IRQ numbers,
> (mapped to the MSI vectors).
> 
> Therefore, although interrupts from dummy ports are not
> desired they are still enabled. We do not request IRQs
> for dummy ports, but that only means we do not assign
> AHCI-specific ISRs to corresponding IRQ numbers.
> 
> As result, dummy port interrupts still could come and
> traverse all the way from the PCI device to the kernel,
> causing unnecessary overhead.
> 
> This update disables IRQs for dummy ports and prevents
> the described issue.
> 
> Signed-off-by: Alexander Gordeev <agordeev@...hat.com>
> Cc: Tejun Heo <tj@...nel.org>
> Cc: David Milburn <dmilburn@...hat.com>
> Cc: linux-ide@...r.kernel.org

David, can you please test the patch?

Thanks.

-- 
tejun
--
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/