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  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:	Thu, 07 Aug 2014 08:13:24 +0200
From:	Paolo Bonzini <pbonzini@...hat.com>
To:	"Zhang, Yang Z" <yang.z.zhang@...el.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

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? :)

Paolo
--
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/

Powered by blists - more mailing lists