linux-kernel - RE: [PATCH] KVM: x86: always exit on EOIs for interrupts listed in the IOAPIC redir table

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] [day] [month] [year] [list]

Message-ID: <A9667DDFB95DB7438FA9D7D576C3D87E0AB52909@SHSMSX104.ccr.corp.intel.com>
Date:	Thu, 7 Aug 2014 06:17:53 +0000
From:	"Zhang, Yang Z" <yang.z.zhang@...el.com>
To:	Paolo Bonzini <pbonzini@...hat.com>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
CC:	"alex.williamson@...hat.com" <alex.williamson@...hat.com>,
	"kvm@...r.kernel.org" <kvm@...r.kernel.org>,
	"stable@...r.kernel.org" <stable@...r.kernel.org>
Subject: RE: [PATCH] KVM: x86: always exit on EOIs for interrupts listed in
 the IOAPIC redir table

Paolo Bonzini wrote on 2014-08-07:
> Il 07/08/2014 03:31, Zhang, Yang Z ha scritto:
>> Let me give an example to see whether my concern is a real problem:
>> Guest allocates a vector and set it in IOAPIC entry to deliver
>> interrupt. Later it masks the IOAPIC entry(means stop the
>> corresponding device) and assign this vector to a MSI device. With
>> this patch, even the vector is not used by IOAPIC, but it still set
>> eoi exit bitmap unconditionally. The subsequent EOIs to MSI device
>> will force vmexit. Could this happen?
> 
> Yes, I guess it could.  I'm not sure whether it could on Linux or Windows.
> 
>> I think the right fixing is to check the ISR plus TMR to construct
>> the eoi exit bitmap.
> 
> Do you care enough to propose a patch? :)
> 

Sure. I will do it.

> Paolo


Best regards,
Yang

--
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/