linux-kernel - Re: [patch] x86_64, irq: check remote IRR bit before migrating level triggered irq

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: <m11whe0zal.fsf@ebiederm.dsl.xmission.com>
Date:	Fri, 18 May 2007 12:20:02 -0600
From:	ebiederm@...ssion.com (Eric W. Biederman)
To:	"Yinghai Lu" <yhlu.kernel@...il.com>
Cc:	"Siddha, Suresh B" <suresh.b.siddha@...el.com>, mingo@...e.hu,
	ak@...e.de, akpm@...ux-foundation.org,
	linux-kernel@...r.kernel.org, "Zou, Nanhai" <nanhai.zou@...el.com>,
	"Mallick, Asit K" <asit.k.mallick@...el.com>,
	"Packard, Keith" <keith.packard@...el.com>
Subject: Re: [patch] x86_64, irq: check remote IRR bit before migrating level triggered irq

"Yinghai Lu" <yhlu.kernel@...il.com> writes:

> On 5/18/07, Eric W. Biederman <ebiederm@...ssion.com> wrote:
>> We can solve the problem without doing that, and keeping the same
>> vector number during migration keeps x86 from scaling.
>
> I mean ioapic level irq couls be limited. new device could use MSI or
> HT irq directly and less irq routing problem.

Possibly.  It really doesn't buy us anything until most irqs are MSI
which they are not yet.

>> Personally I would prefer to disallow irq migration.
> ? typo?
> For amd platform with different hypertransport chain on different
> nodes, irq migration is needed.

irqs not on cpu0 are needed.  irq migration is less necessary, and I periodically
think we are insane for supporting it.

Eric
-
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/