linux-kernel - Re: [PATCH 7/9] virtio-pci: harden INTX interrupts

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: <20210913175428-mutt-send-email-mst@kernel.org>
Date:   Mon, 13 Sep 2021 18:01:04 -0400
From:   "Michael S. Tsirkin" <mst@...hat.com>
To:     Thomas Gleixner <tglx@...utronix.de>
Cc:     Jason Wang <jasowang@...hat.com>,
        virtualization@...ts.linux-foundation.org,
        linux-kernel@...r.kernel.org, f.hetzelt@...berlin.de,
        david.kaplan@....com, konrad.wilk@...cle.com,
        Peter Zijlstra <peterz@...radead.org>,
        Will Deacon <will@...nel.org>,
        Boqun Feng <boqun.feng@...il.com>,
        "Paul E. McKenney" <paulmck@...nel.org>
Subject: Re: [PATCH 7/9] virtio-pci: harden INTX interrupts

On Mon, Sep 13, 2021 at 11:36:24PM +0200, Thomas Gleixner wrote:
> >From the interrupt perspective the sequence:
> 
>         disable_irq();
>         vp_dev->intx_soft_enabled = true;
>         enable_irq();
> 
> is perfectly fine as well. Any interrupt arriving during the disabled
> section will be reraised on enable_irq() in hardware because it's a
> level interrupt. Any resulting failure is either a hardware or a
> hypervisor bug.

yes but it's a shared interrupt. what happens if multiple callers do
this in parallel?