Sender: Guenter Roeck <groeck7@gmail.com>
Subject: Re: Linux 5.16-rc3
To:     Bjorn Helgaas <helgaas@kernel.org>,
        Sergio Paracuellos <sergio.paracuellos@gmail.com>
Cc:     Randy Dunlap <rdunlap@infradead.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>,
        Bjorn Helgaas <bhelgaas@google.com>, linux-pci@vger.kernel.org
References: <20211201203822.GA2840039@bhelgaas>
From:   Guenter Roeck <linux@roeck-us.net>
Message-ID: <542e38c7-afed-ebf5-5254-8aa6ee22b01a@roeck-us.net>
Date:   Wed, 1 Dec 2021 12:50:02 -0800
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On 12/1/21 12:38 PM, Bjorn Helgaas wrote:
> [+cc linux-pci]
> 
> On Mon, Nov 29, 2021 at 01:18:12PM +0100, Sergio Paracuellos wrote:
>> On Mon, Nov 29, 2021 at 5:17 AM Guenter Roeck <linux@roeck-us.net> wrote:
>>> On 11/28/21 7:07 PM, Randy Dunlap wrote:
>>>> On 11/28/21 17:59, Guenter Roeck wrote:
>>>>> ...
>>>>> Build results:
>>>>>      total: 153 pass: 152 fail: 1
>>>>> Failed builds:
>>>>>      mips:allmodconfig
>>>>> Qemu test results:
>>>>>      total: 482 pass: 482 fail: 0
>>>>>
>>>>> Building mips:allmodconfig ... failed
>>>>> --------------
>>>>> Error log:
>>>>> ERROR: modpost: missing MODULE_LICENSE() in drivers/pci/controller/pcie-mt7621.o
>>>>> ERROR: modpost: "mips_cm_unlock_other" [drivers/pci/controller/pcie-mt7621.ko] undefined!
>>>>> ERROR: modpost: "mips_cpc_base" [drivers/pci/controller/pcie-mt7621.ko] undefined!
>>>>> ERROR: modpost: "mips_cm_lock_other" [drivers/pci/controller/pcie-mt7621.ko] undefined!
>>>>> ERROR: modpost: "mips_cm_is64" [drivers/pci/controller/pcie-mt7621.ko] undefined!
>>>>> ERROR: modpost: "mips_gcr_base" [drivers/pci/controller/pcie-mt7621.ko] undefined!
>>>>>
>>>>> There is still no fix for the mips:allmodconfig build problem as far
>>>>> as I can see. It is a bit odd, because the fix would be as simple as
>>>>>
>>>>>    config PCIE_MT7621
>>>>> -    tristate "MediaTek MT7621 PCIe Controller"
>>>>> -    depends on (RALINK && SOC_MT7621) || (MIPS && COMPILE_TEST)
>>>>> +    bool "MediaTek MT7621 PCIe Controller"
>>>>> +    depends on SOC_MT7621 || (MIPS && COMPILE_TEST)
>>>>>        select PHY_MT7621_PCI
>>>>>        default SOC_MT7621
>>>>>        help
>>>>>
>>>>> Context: tristate doesn't make sense here because both RALINK and
>>>>> SOC_MT7621 are bool. Also, RALINK is redundant because SOC_MT7621
>>>>> already depends on it. The compile failure is due to missing exported
>>>>> symbols, and it is only seen if PCIE_MT7621=m - which is only possible
>>>>> if COMPILE_TEST=y. In other words, the dependencies above are set such
>>>>> that test builds, and only test builds, fail.
>>>>>
>>>>> The problem was introduced with commit 2bdd5238e756 ("PCI: mt7621:
>>>>> Add MediaTek MT7621 PCIe host controller driver"). Copying some of
>>>>> those responsible to see if we can expect a solution sometime soon.
> 
> Can we do a minimal patch along the lines of the above for v5.16?
> 

I would suggest to either do that or, if module support is mandatory,
revert the patch and re-apply it if and when it can be built as module.

Guenter