linux-kernel - RE: [PATCH] fix x2apic defect that Linux kernel doesn't mask 8259A interrupt during the time window between changing VT-d table base address and initializing these VT-d entries(smpboot.c and apic.c )

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, 10 Oct 2012 17:07:19 -0700
From:	Suresh Siddha <suresh.b.siddha@...el.com>
To:	"Zhang, Lin-Bao (Linux Kernel R&D)" <linbao.zhang@...com>
Cc:	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	"alan@...rguk.ukuu.org.uk" <alan@...rguk.ukuu.org.uk>,
	"mingo@...hat.com" <mingo@...hat.com>,
	"Croxon, Nigel" <nigel.croxon@...com>,
	"tglx@...utronix.de" <tglx@...utronix.de>,
	"hpa@...or.com" <hpa@...or.com>, "x86@...nel.org" <x86@...nel.org>,
	"a.p.zijlstra@...llo.nl" <a.p.zijlstra@...llo.nl>,
	"Sakkinen, Jarkko" <jarkko.sakkinen@...el.com>,
	"joerg.roedel@....com" <joerg.roedel@....com>,
	"agordeev@...hat.com" <agordeev@...hat.com>,
	"yinghai@...nel.org" <yinghai@...nel.org>,
	"stable@...nel.org" <stable@...nel.org>
Subject: RE: [PATCH] fix x2apic defect that Linux kernel doesn't mask 8259A
 interrupt during the time window between changing VT-d table base address
 and initializing these VT-d entries(smpboot.c and apic.c )

On Wed, 2012-10-10 at 00:26 +0000, Zhang, Lin-Bao (Linux Kernel R&D)
wrote:

> So , we can think ,as your patch , during the window , IO-apic is
> useless or we can think IO-APIC doesn't exist ? 
> Could you mind please sharing your design details ? thanks very much! 

Between the window of interrupt-remapping enabled and the masked IO-APIC
RTE's are configured properly, linux kernel doesn't wait/depend on any
external interrupts.

> > Can you please apply the appended patch to 2.6.32 kernel and see if the issue
> > you mentioned gets fixed? If so, we can ask the -stable and OSV's teams to
> > pick up this fix.
> Yes , it can resolve current issue. 

Thanks for testing it out.

I will add the appropriate changelog and send the patch out (to 2.6.32
stable and OSV kernels) with your "Tested-by:" if you are ok.

thanks,
suresh

--
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/