From: Esther Shimanovich <eshimanovich@chromium.org>
To: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>,
Mario Limonciello <mario.limonciello@amd.com>,
Lukas Wunner <lukas@wunner.de>,
Bjorn Helgaas <bhelgaas@google.com>,
linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org,
Rajat Jain <rajatja@google.com>
Subject: Re: [PATCH v4] PCI: Relabel JHL6540 on Lenovo X1 Carbon 7,8
Date: Fri, 19 Jan 2024 11:03:18 -0500 [thread overview]
Message-ID: <CA+Y6NJHhTaroqJKEvOebRvbTdgkxW8tqFvq5MrOVE9swmwmtOw@mail.gmail.com> (raw)
In-Reply-To: <20240119102258.GE2543524@black.fi.intel.com>
On Thu, Jan 18, 2024 at 1:01 AM Mika Westerberg
<mika.westerberg@linux.intel.com> wrote:
>
> Well that's pretty much all Intel Titan Ridge and Maple Ridge based
> systems. Some early ones did not use IOMMU but all the rest do.
...
> Before Intel Ice Lake it was all discrete and it is still discrete with
> the Barlow Ridge controller who will have exact same ExternalFacing port
> as the previous models.
Next week I'll try those devices in our inventory to see if I can find
another one with this bug. I'll get back to you on that!
On Fri, Jan 19, 2024 at 2:58 AM Mika Westerberg
<mika.westerberg@linux.intel.com> wrote:
>
> Now if I understand the reason behind this patch is actually not about
> "removability" that much than about identifying a trusted vs. untrusted
> device and attaching a driver to those. I was under impression that
> there is already a solution to this in ChromeOS kernel. It has an
> allowlist of drivers that are allowed to attach these devices and that
> includes the PCIe port drivers, xhci_hcd and the thunderbolt driver,
> possibly something else too. Is this not working for your case?
This device shouldn’t be treated as a removable thunderbolt device
that is enabled by policy because it is an internal device that should
be trusted in the first place.
Even so, while learning about this problem I tried modifying the
ChromeOS policy but it ended up not fixing the issue because it seems
like there is an expectation for it to see an existing “fixed”
thunderbolt port before it loads anything else. But the fixed
thunderbolt port is prevented from enumerating during bootup, before
the policy has a chance to work.
On Fri, Jan 19, 2024 at 5:23 AM Mika Westerberg
<mika.westerberg@linux.intel.com> wrote:
>
> The below "might" work:
>
> 1. A device that is directly behind a PCIe root or downstream port that
> has ->external_facing == 1.
>
> 2. It is a PCIe endpoint.
>
> 3. It is a sibling to or has any of the below PCI IDs (see
> drivers/thunderbolt/nhi.h for the definitions):
External pci devices seem to have the same kinds of chips in them. So
this wouldn’t distinguish the “fixed but discrete” embedded pci
devices from the “removable” pcie through usb devices. My monitor with
thunderbolt capabilities has the JHL7540 chip in it. From the kernel's
perspective, I have only found that the subsystem id is what
distinguishes these devices.
That is, unless I am missing something in your proposal that would
distinguish a fixed JHL6540 chip from an external JHL6540 chip. Please
correct me on any assumptions I get wrong!
next prev parent reply other threads:[~2024-01-19 16:03 UTC|newest]
Thread overview: 52+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-12-21 20:53 [PATCH v4] PCI: Relabel JHL6540 on Lenovo X1 Carbon 7,8 Esther Shimanovich
2023-12-21 23:15 ` Dmitry Torokhov
2023-12-27 0:15 ` Bjorn Helgaas
2023-12-28 13:25 ` Lukas Wunner
2023-12-28 13:39 ` Mika Westerberg
2024-01-17 21:21 ` Esther Shimanovich
2024-01-18 6:00 ` Mika Westerberg
2024-01-18 15:47 ` Mario Limonciello
2024-01-18 16:12 ` Dmitry Torokhov
2024-01-18 16:21 ` Dmitry Torokhov
2024-01-19 5:37 ` Mika Westerberg
2024-01-19 7:48 ` Mika Westerberg
2024-01-19 10:22 ` Mika Westerberg
2024-01-19 16:03 ` Esther Shimanovich [this message]
2024-01-22 6:10 ` Mika Westerberg
2024-01-22 23:50 ` Mario Limonciello
2024-01-23 6:18 ` Mika Westerberg
2024-01-25 23:45 ` Esther Shimanovich
2024-04-15 22:34 ` Esther Shimanovich
2024-04-16 5:03 ` Mika Westerberg
2024-04-18 19:43 ` Esther Shimanovich
2024-04-19 4:49 ` Mika Westerberg
2024-04-22 19:17 ` Esther Shimanovich
2024-04-22 19:21 ` Mario Limonciello
2024-04-23 5:33 ` Mika Westerberg
2024-04-23 8:31 ` Lukas Wunner
2024-04-23 8:40 ` Mika Westerberg
2024-04-23 16:59 ` Mario Limonciello
2024-04-24 8:56 ` Mika Westerberg
2024-04-25 21:16 ` Esther Shimanovich
2024-04-26 4:52 ` Mika Westerberg
2024-04-26 15:58 ` Esther Shimanovich
2024-04-27 5:35 ` Lukas Wunner
2024-04-27 7:41 ` Mika Westerberg
2024-04-27 7:08 ` Lukas Wunner
2024-04-27 15:09 ` Lukas Wunner
2024-05-01 22:23 ` Esther Shimanovich
2024-05-02 4:38 ` Mika Westerberg
2024-05-02 9:54 ` Mario Limonciello
2024-05-02 10:07 ` Mika Westerberg
2024-05-08 5:14 ` Lukas Wunner
2024-05-10 5:26 ` Mika Westerberg
2024-05-10 15:44 ` Esther Shimanovich
2024-05-11 4:38 ` Mika Westerberg
2024-05-11 5:43 ` Mika Westerberg
2024-05-15 18:53 ` Esther Shimanovich
2024-05-15 20:35 ` Lukas Wunner
2024-05-15 20:51 ` Lukas Wunner
2024-05-15 21:44 ` Esther Shimanovich
2024-05-16 8:30 ` Mika Westerberg
2024-05-16 10:03 ` Mika Westerberg
2024-05-16 9:16 ` Mika Westerberg
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=CA+Y6NJHhTaroqJKEvOebRvbTdgkxW8tqFvq5MrOVE9swmwmtOw@mail.gmail.com \
--to=eshimanovich@chromium.org \
--cc=bhelgaas@google.com \
--cc=dmitry.torokhov@gmail.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-pci@vger.kernel.org \
--cc=lukas@wunner.de \
--cc=mario.limonciello@amd.com \
--cc=mika.westerberg@linux.intel.com \
--cc=rajatja@google.com \
/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
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).