linux-kernel - Re: [PATCH 3/4] AHCI: Conserve interrupts with pci_enable_msi_block

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: <20130903182731.GA27092@mtj.dyndns.org>
Date:	Tue, 3 Sep 2013 14:27:31 -0400
From:	Tejun Heo <tj@...nel.org>
To:	Alexander Gordeev <agordeev@...hat.com>
Cc:	linux-kernel@...r.kernel.org, x86@...nel.org,
	linux-pci@...r.kernel.org, linux-ide@...r.kernel.org,
	Ingo Molnar <mingo@...nel.org>, Joerg Roedel <joro@...tes.org>,
	Jan Beulich <JBeulich@...e.com>,
	Bjorn Helgaas <bhelgaas@...gle.com>
Subject: Re: [PATCH 3/4] AHCI: Conserve interrupts with
 pci_enable_msi_block_part() interface

Hello,

On Tue, Sep 03, 2013 at 06:19:06PM +0200, Alexander Gordeev wrote:
> We must enable maximum possible number of MSIs - the one reported in
> Multiple Message Capable register. Otherwise ICH device will fallback
> to MRSM. IOW, if the result of roundup_pow_of_two(n_ports) is not what
> in Multiple Message Capable register (i.e. as roundup_pow_of_two(6) vs 16)
> ICH will enforce MRSM mode.

Hmmm... I think the interface in general is pretty messy.  Wouldn't it
be much cleaner to have a separate function to query MSICAP and let
the function just return success / failure?

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/