All of lore.kernel.org
 help / color / mirror / Atom feed
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: Andi Kleen <ak@linux.intel.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>,
	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>,
	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, "Reshetova,
	Elena" <elena.reshetova@intel.com>
Subject: Re: [PATCH v2 2/6] driver core: Add common support to skip probe for un-authorized devices
Date: Thu, 30 Sep 2021 19:23:52 +0200	[thread overview]
Message-ID: <YVXyqBGa5Ix5MzmD@kroah.com> (raw)
In-Reply-To: <f4b5a269-843f-6911-24fe-ebffb2bd4f9e@linux.intel.com>

On Thu, Sep 30, 2021 at 10:17:09AM -0700, Andi Kleen wrote:
> 
> > > The "it" that I referred to is the claim that no driver should be
> > > touching hardware in their module init call. Andi seems to think
> > > such drivers are worth working around with a special remap API.
> > Andi is wrong.
> 
> While overall it's a small percentage of the total, there are still quite a
> few drivers that do touch hardware in init functions. Sometimes for good
> reasons -- they need to do some extra probing to discover something that is
> not enumerated -- sometimes just because it's very old legacy code that
> predates the modern driver model.

Are any of them in the kernel today?

PCI drivers should not be messing with this, we have had well over a
decade to fix that up.

> The legacy drivers could be fixed, but nobody really wants to touch them
> anymore and they're impossible to test.

Pointers to them?

> The drivers that probe something that is not enumerated in a standard way
> have no choice, it cannot be implemented in a different way.

PCI devices are not enumerated in a standard way???

> So instead we're using a "firewall" the prevents these drivers from doing
> bad things by not allowing ioremap access unless opted in, and also do some
> filtering on the IO ports The device filter is still the primary mechanism,
> the ioremap filtering is just belts and suspenders for those odd cases.

That's horrible, don't try to protect the kernel from itself.  Just fix
the drivers.

If you point me at them, I will be glad to have a look and throw some
interns on them.

But really, you all could have fixed them up by now if Intel really
cared about it :(

> If you want we can send an exact list, we did some analysis using a patched
> smatch tool.

Please do.

thanks,

greg k-h

WARNING: multiple messages have this Message-ID
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: Andi Kleen <ak@linux.intel.com>
Cc: Jonathan Corbet <corbet@lwn.net>,
	Kuppuswamy Sathyanarayanan
	<sathyanarayanan.kuppuswamy@linux.intel.com>,
	Kuppuswamy Sathyanarayanan <knsathya@kernel.org>,
	"Michael S. Tsirkin" <mst@redhat.com>,
	Michael Jamet <michael.jamet@intel.com>,
	linux-pci@vger.kernel.org, x86@kernel.org,
	virtualization@lists.linux-foundation.org,
	Yehezkel Bernat <YehezkelShB@gmail.com>,
	linux-kernel@vger.kernel.org,
	Andreas Noever <andreas.noever@gmail.com>,
	Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
	"Reshetova, Elena" <elena.reshetova@intel.com>,
	Bjorn Helgaas <bhelgaas@google.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	linux-usb@vger.kernel.org,
	Mika Westerberg <mika.westerberg@linux.intel.com>,
	Dan Williams <dan.j.williams@intel.com>,
	"Rafael J . Wysocki" <rafael@kernel.org>
Subject: Re: [PATCH v2 2/6] driver core: Add common support to skip probe for un-authorized devices
Date: Thu, 30 Sep 2021 19:23:52 +0200	[thread overview]
Message-ID: <YVXyqBGa5Ix5MzmD@kroah.com> (raw)
In-Reply-To: <f4b5a269-843f-6911-24fe-ebffb2bd4f9e@linux.intel.com>

On Thu, Sep 30, 2021 at 10:17:09AM -0700, Andi Kleen wrote:
> 
> > > The "it" that I referred to is the claim that no driver should be
> > > touching hardware in their module init call. Andi seems to think
> > > such drivers are worth working around with a special remap API.
> > Andi is wrong.
> 
> While overall it's a small percentage of the total, there are still quite a
> few drivers that do touch hardware in init functions. Sometimes for good
> reasons -- they need to do some extra probing to discover something that is
> not enumerated -- sometimes just because it's very old legacy code that
> predates the modern driver model.

Are any of them in the kernel today?

PCI drivers should not be messing with this, we have had well over a
decade to fix that up.

> The legacy drivers could be fixed, but nobody really wants to touch them
> anymore and they're impossible to test.

Pointers to them?

> The drivers that probe something that is not enumerated in a standard way
> have no choice, it cannot be implemented in a different way.

PCI devices are not enumerated in a standard way???

> So instead we're using a "firewall" the prevents these drivers from doing
> bad things by not allowing ioremap access unless opted in, and also do some
> filtering on the IO ports The device filter is still the primary mechanism,
> the ioremap filtering is just belts and suspenders for those odd cases.

That's horrible, don't try to protect the kernel from itself.  Just fix
the drivers.

If you point me at them, I will be glad to have a look and throw some
interns on them.

But really, you all could have fixed them up by now if Intel really
cared about it :(

> If you want we can send an exact list, we did some analysis using a patched
> smatch tool.

Please do.

thanks,

greg k-h
_______________________________________________
Virtualization mailing list
Virtualization@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/virtualization

  reply	other threads:[~2021-09-30 17:23 UTC|newest]

Thread overview: 132+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-09-30  1:05 [PATCH v2 0/6] Add device filter support Kuppuswamy Sathyanarayanan
2021-09-30  1:05 ` [PATCH v2 1/6] driver core: Move the "authorized" attribute from USB/Thunderbolt to core Kuppuswamy Sathyanarayanan
2021-09-30  1:42   ` Alan Stern
2021-09-30  1:42     ` Alan Stern
2021-09-30  1:55     ` Dan Williams
2021-09-30  1:55       ` Dan Williams
2021-09-30  2:38       ` Kuppuswamy, Sathyanarayanan
2021-09-30  4:59         ` Dan Williams
2021-09-30  4:59           ` Dan Williams
2021-09-30  9:05           ` Rafael J. Wysocki
2021-09-30  9:05             ` Rafael J. Wysocki
2021-09-30 14:59       ` Alan Stern
2021-09-30 14:59         ` Alan Stern
2021-09-30 15:25         ` Dan Williams
2021-09-30 15:25           ` Dan Williams
2021-09-30 11:19   ` Yehezkel Bernat
2021-09-30 15:28     ` Dan Williams
2021-09-30 15:28       ` Dan Williams
2021-09-30 18:25       ` Yehezkel Bernat
2021-09-30 19:04         ` Dan Williams
2021-09-30 19:04           ` Dan Williams
2021-09-30 19:50           ` Kuppuswamy, Sathyanarayanan
2021-09-30 20:23             ` Dan Williams
2021-09-30 20:23               ` Dan Williams
2021-09-30  1:05 ` [PATCH v2 2/6] driver core: Add common support to skip probe for un-authorized devices Kuppuswamy Sathyanarayanan
2021-09-30 10:59   ` Michael S. Tsirkin
2021-09-30 10:59     ` Michael S. Tsirkin
2021-09-30 13:52     ` Greg Kroah-Hartman
2021-09-30 13:52       ` Greg Kroah-Hartman
2021-09-30 14:38       ` Michael S. Tsirkin
2021-09-30 14:38         ` Michael S. Tsirkin
2021-09-30 14:49         ` Greg Kroah-Hartman
2021-09-30 14:49           ` Greg Kroah-Hartman
2021-09-30 15:00           ` Michael S. Tsirkin
2021-09-30 15:00             ` Michael S. Tsirkin
2021-09-30 15:22             ` Greg Kroah-Hartman
2021-09-30 15:22               ` Greg Kroah-Hartman
2021-09-30 17:17               ` Andi Kleen
2021-09-30 17:17                 ` Andi Kleen
2021-09-30 17:23                 ` Greg Kroah-Hartman [this message]
2021-09-30 17:23                   ` Greg Kroah-Hartman
2021-09-30 19:15                   ` Andi Kleen
2021-09-30 19:15                     ` Andi Kleen
2021-10-01  6:29                     ` Greg Kroah-Hartman
2021-10-01  6:29                       ` Greg Kroah-Hartman
2021-10-01 15:51                       ` Alan Stern
2021-10-01 15:51                         ` Alan Stern
2021-10-01 15:56                         ` Andi Kleen
2021-10-01 15:56                           ` Andi Kleen
2021-09-30 14:43       ` Alan Stern
2021-09-30 14:43         ` Alan Stern
2021-09-30 14:48         ` Michael S. Tsirkin
2021-09-30 14:48           ` Michael S. Tsirkin
2021-09-30 15:32           ` Alan Stern
2021-09-30 15:32             ` Alan Stern
2021-09-30 15:52             ` Michael S. Tsirkin
2021-09-30 15:52               ` Michael S. Tsirkin
2021-09-30 14:58         ` Michael S. Tsirkin
2021-09-30 14:58           ` Michael S. Tsirkin
2021-09-30 15:35           ` Alan Stern
2021-09-30 15:35             ` Alan Stern
2021-09-30 15:59             ` Michael S. Tsirkin
2021-09-30 15:59               ` Michael S. Tsirkin
2021-09-30 19:23               ` Andi Kleen
2021-09-30 19:23                 ` Andi Kleen
2021-09-30 20:44                 ` Alan Stern
2021-09-30 20:44                   ` Alan Stern
2021-09-30 20:52                   ` Dan Williams
2021-09-30 20:52                     ` Dan Williams
2021-10-01  1:41                     ` Alan Stern
2021-10-01  1:41                       ` Alan Stern
2021-10-01  2:20                       ` Dan Williams
2021-10-01  2:20                         ` Dan Williams
2021-09-30 21:12                   ` Andi Kleen
2021-09-30 21:12                     ` Andi Kleen
2021-09-30  1:05 ` [PATCH v2 3/6] driver core: Allow arch to initialize the authorized attribute Kuppuswamy Sathyanarayanan
2021-09-30  1:05 ` [PATCH v2 4/6] virtio: Initialize authorized attribute for confidential guest Kuppuswamy Sathyanarayanan
2021-09-30 11:03   ` Michael S. Tsirkin
2021-09-30 11:03     ` Michael S. Tsirkin
2021-09-30 13:36     ` Dan Williams
2021-09-30 13:36       ` Dan Williams
2021-09-30 13:49       ` Greg Kroah-Hartman
2021-09-30 13:49         ` Greg Kroah-Hartman
2021-09-30 15:18       ` Kuppuswamy, Sathyanarayanan
2021-09-30 15:20         ` Michael S. Tsirkin
2021-09-30 15:20           ` Michael S. Tsirkin
2021-09-30 15:23           ` Kuppuswamy, Sathyanarayanan
2021-09-30 15:23         ` Greg Kroah-Hartman
2021-09-30 15:23           ` Greg Kroah-Hartman
2021-09-30 19:04           ` Kuppuswamy, Sathyanarayanan
2021-09-30 19:16             ` Kuppuswamy, Sathyanarayanan
2021-09-30 19:30             ` Andi Kleen
2021-09-30 19:30               ` Andi Kleen
2021-09-30 19:40               ` Kuppuswamy, Sathyanarayanan
2021-10-01  7:03             ` Greg Kroah-Hartman
2021-10-01  7:03               ` Greg Kroah-Hartman
2021-10-01 15:49               ` Andi Kleen
2021-10-01 15:49                 ` Andi Kleen
2021-10-02 11:04                 ` Michael S. Tsirkin
2021-10-02 11:04                   ` Michael S. Tsirkin
2021-10-02 11:14                   ` Greg Kroah-Hartman
2021-10-02 11:14                     ` Greg Kroah-Hartman
2021-10-02 14:20                     ` Andi Kleen
2021-10-02 14:20                       ` Andi Kleen
2021-10-02 14:44                       ` Greg Kroah-Hartman
2021-10-02 14:44                         ` Greg Kroah-Hartman
2021-10-02 18:40                       ` Michael S. Tsirkin
2021-10-02 18:40                         ` Michael S. Tsirkin
2021-10-03  6:40                         ` Greg Kroah-Hartman
2021-10-03  6:40                           ` Greg Kroah-Hartman
2021-10-04 21:04                       ` Dan Williams
2021-10-04 21:04                         ` Dan Williams
2021-10-01 16:13               ` Dan Williams
2021-10-01 16:13                 ` Dan Williams
2021-10-01 16:45                 ` Alan Stern
2021-10-01 16:45                   ` Alan Stern
2021-10-01 18:09                   ` Dan Williams
2021-10-01 18:09                     ` Dan Williams
2021-10-01 19:00                     ` Alan Stern
2021-10-01 19:00                       ` Alan Stern
2021-10-01 19:45                       ` Kuppuswamy, Sathyanarayanan
2021-10-01 19:57                       ` Dan Williams
2021-10-01 19:57                         ` Dan Williams
2021-10-04  5:16                         ` Mika Westerberg
2021-10-05 22:33                           ` Dan Williams
2021-10-05 22:33                             ` Dan Williams
2021-10-06  5:45                             ` Greg Kroah-Hartman
2021-10-06  5:45                               ` Greg Kroah-Hartman
2021-09-30 19:25         ` Andi Kleen
2021-09-30 19:25           ` Andi Kleen
2021-09-30  1:05 ` [PATCH v2 5/6] x86/tdx: Add device filter support for x86 TDX guest platform Kuppuswamy Sathyanarayanan
2021-09-30  1:05 ` [PATCH v2 6/6] PCI: Initialize authorized attribute for confidential guest Kuppuswamy Sathyanarayanan

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=YVXyqBGa5Ix5MzmD@kroah.com \
    --to=gregkh@linuxfoundation.org \
    --cc=YehezkelShB@gmail.com \
    --cc=ak@linux.intel.com \
    --cc=andreas.noever@gmail.com \
    --cc=bhelgaas@google.com \
    --cc=bp@alien8.de \
    --cc=corbet@lwn.net \
    --cc=dan.j.williams@intel.com \
    --cc=elena.reshetova@intel.com \
    --cc=jasowang@redhat.com \
    --cc=knsathya@kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-pci@vger.kernel.org \
    --cc=linux-usb@vger.kernel.org \
    --cc=michael.jamet@intel.com \
    --cc=mika.westerberg@linux.intel.com \
    --cc=mingo@redhat.com \
    --cc=mst@redhat.com \
    --cc=rafael@kernel.org \
    --cc=sathyanarayanan.kuppuswamy@linux.intel.com \
    --cc=tglx@linutronix.de \
    --cc=virtualization@lists.linux-foundation.org \
    --cc=x86@kernel.org \
    --subject='Re: [PATCH v2 2/6] driver core: Add common support to skip probe for un-authorized devices' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.