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Date:   Thu, 30 Sep 2021 11:35:09 -0400
From:   Alan Stern <stern@rowland.harvard.edu>
To:     "Michael S. Tsirkin" <mst@redhat.com>
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Kuppuswamy Sathyanarayanan 
        <sathyanarayanan.kuppuswamy@linux.intel.com>,
        Borislav Petkov <bp@alien8.de>, x86@kernel.org,
        Bjorn Helgaas <bhelgaas@google.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>,
        Andreas Noever <andreas.noever@gmail.com>,
        Michael Jamet <michael.jamet@intel.com>,
        Yehezkel Bernat <YehezkelShB@gmail.com>,
        "Rafael J . Wysocki" <rafael@kernel.org>,
        Mika Westerberg <mika.westerberg@linux.intel.com>,
        Jonathan Corbet <corbet@lwn.net>,
        Jason Wang <jasowang@redhat.com>,
        Dan Williams <dan.j.williams@intel.com>,
        Andi Kleen <ak@linux.intel.com>,
        Kuppuswamy Sathyanarayanan <knsathya@kernel.org>,
        linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org,
        linux-usb@vger.kernel.org,
        virtualization@lists.linux-foundation.org
Subject: Re: [PATCH v2 2/6] driver core: Add common support to skip probe for
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On Thu, Sep 30, 2021 at 10:58:07AM -0400, Michael S. Tsirkin wrote:
> On Thu, Sep 30, 2021 at 10:43:05AM -0400, Alan Stern wrote:
> > I don't see any point in talking about "untrusted drivers".  If a 
> > driver isn't trusted then it doesn't belong in your kernel.  Period.  
> > When you load a driver into your kernel, you are implicitly trusting 
> > it (aside from limitations imposed by security modules).
> 
> Trusting it to do what? Historically a ton of drivers did not
> validate input from devices they drive. Most still don't.

Trusting it to behave properly (i.e., not destroy your system, among 
other things).

The fact that many drivers haven't been trustworthy is beside the 
point.  By loading them into your kernel, you are trusting them 
regardless.  In the end, you may regret having done so.  :-(

Alan Stern