RE: [PATCH] mei: make hdcp and pxp depend on X86 && PCI

From: Winkler, Tomas
Date: Wed Apr 26 2023 - 14:11:43 EST


>
> On Tue, Apr 25, 2023, at 16:27, Adam Borowski wrote:
> > On Tue, Apr 25, 2023 at 03:40:10PM +0200, Greg Kroah-Hartman wrote:
> >> On Tue, Apr 25, 2023 at 01:52:10PM +0200, Adam Borowski wrote:
> >> > On Tue, Apr 25, 2023 at 04:39:23AM +0000, Winkler, Tomas wrote:
> >> > > What is the exact issue you are experiencing, can you add the error
> message this fixes?
> >> >
> >> > The problem doesn't trigger in mainline
> >>
> >> Then it's nothing we need to worry about in mainline. If/when other
> >> changes ever happen to need it here in mainline, we will gladly take
> >> the change.
> >>
> >> For obvious reasons, we can't take patches for issues outside of our
> >> codebase. Nor do you want us to, as that way lies madness and an
> >> unmaintainable mess.
> >
> > The problem in mainline is inconsistency: out of 6 config items, 4
> > repeat the "depends on X86 && PCI" line, the other 2 do not. There's
> > indeed no immediate functional issue, but I'd argue that a dormant bug is
> still a bug.

The MEI protocol (CONFIG_INTEL_MEI) is not PCI or X86 dependent.
INTEL_MEI_GSC is PCI dependent but not X86. (Hope I correct also on implementation side)
They HW layers are currently X86 dependent.

> >
> > So we can fix the cosmetic (currently) issue on its own, or as part of
> > the large patchset -- the latter having a side effect of stuffing your
> > mailboxes more than needed (neither Greg, Arnd, nor Tomas are involved
> in other bits).
> >
> > But do the selects really require so much duplication? Perhaps I'm
> > trying to fix the underlying issue wrong?
>
> I think something along these lines would do (untested):
>
> diff --git a/drivers/misc/mei/Kconfig b/drivers/misc/mei/Kconfig index
> d21486d69df2..8e5d79cff80b 100644
> --- a/drivers/misc/mei/Kconfig
> +++ b/drivers/misc/mei/Kconfig
> @@ -1,6 +1,6 @@
> # SPDX-License-Identifier: GPL-2.0
> # Copyright (c) 2003-2019, Intel Corporation. All rights reserved.
> -config INTEL_MEI
> +menuconfig INTEL_MEI
> tristate "Intel Management Engine Interface"
> depends on X86 && PCI
> help
> @@ -13,8 +13,6 @@ config INTEL_MEI
>
> config INTEL_MEI_ME
> tristate "ME Enabled Intel Chipsets"
> - select INTEL_MEI
> - depends on X86 && PCI
> help
> MEI support for ME Enabled Intel chipsets.
>
> @@ -38,8 +36,6 @@ config INTEL_MEI_ME
>
> config INTEL_MEI_TXE
> tristate "Intel Trusted Execution Environment with ME Interface"
> - select INTEL_MEI
> - depends on X86 && PCI
> help
> MEI Support for Trusted Execution Environment device on Intel SoCs
>
> @@ -48,9 +44,7 @@ config INTEL_MEI_TXE
>
> config INTEL_MEI_GSC
> tristate "Intel MEI GSC embedded device"
> - depends on INTEL_MEI
> depends on INTEL_MEI_ME
> - depends on X86 && PCI
> depends on DRM_I915
> help
> Intel auxiliary driver for GSC devices embedded in Intel graphics devices.
> @@ -63,3 +57,4 @@ config INTEL_MEI_GSC
> source "drivers/misc/mei/hdcp/Kconfig"
> source "drivers/misc/mei/pxp/Kconfig"
>
> +endmenu