Received-SPF: pass (google.com: domain of linux-wireless+bounces-2288-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:40f1:3f00::1 as permitted sender) client-ip=2604:1380:40f1:3f00::1;
From: Arend Van Spriel <arend.vanspriel@broadcom.com>
To: Bjorn Helgaas <helgaas@kernel.org>, Dmitry Antipov <dmantipov@yandex.ru>
CC: Hante Meuleman <hante.meuleman@broadcom.com>, <brcm80211-dev-list.pdl@broadcom.com>, <linux-wireless@vger.kernel.org>, Kalle Valo <kvalo@kernel.org>, <lvc-project@linuxtesting.org>
Date: Sat, 20 Jan 2024 13:08:07 +0100
Message-ID: <18d26c56458.279b.9b12b7fc0a3841636cfb5e919b41b954@broadcom.com>
In-Reply-To: <20240119212402.GA186344@bhelgaas>
References: <20240119212402.GA186344@bhelgaas>
User-Agent: AquaMail/1.49.1 (build: 104901407)
Subject: Re: [PATCH 2/2] [v2] wifi: brcmfmac: handle possible MSI enabling error
Precedence: bulk
MIME-Version: 1.0
Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-256;
	boundary="0000000000006afb93060f5f7363"

--0000000000006afb93060f5f7363
Content-Type: text/plain; format=flowed; charset="us-ascii"
Content-Transfer-Encoding: 8bit

On January 19, 2024 10:24:07 PM Bjorn Helgaas <helgaas@kernel.org> wrote:

> On Wed, Jun 14, 2023 at 10:58:48AM +0300, Dmitry Antipov wrote:
>> Handle possible 'pci_enable_msi()' error in
>> 'brcmf_pcie_request_irq()', adjust related code.
>>
>> Found by Linux Verification Center (linuxtesting.org) with SVACE.
>>
>> Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru>
>> ---
>> v2: rebase against wireless-next tree
>> ---
>> .../net/wireless/broadcom/brcm80211/brcmfmac/pcie.c  | 12 ++++++++----
>> 1 file changed, 8 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/pcie.c 
>> b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/pcie.c
>> index 80220685f5e4..f7d9f2cbd60b 100644
>> --- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/pcie.c
>> +++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/pcie.c
>> @@ -965,6 +965,7 @@ static irqreturn_t brcmf_pcie_isr_thread(int irq, void 
>> *arg)
>>
>> static int brcmf_pcie_request_irq(struct brcmf_pciedev_info *devinfo)
>> {
>> + int ret;
>> struct pci_dev *pdev = devinfo->pdev;
>> struct brcmf_bus *bus = dev_get_drvdata(&pdev->dev);
>>
>> @@ -972,16 +973,19 @@ static int brcmf_pcie_request_irq(struct 
>> brcmf_pciedev_info *devinfo)
>>
>> brcmf_dbg(PCIE, "Enter\n");
>>
>> - pci_enable_msi(pdev);
>> + ret = pci_enable_msi(pdev);
>> + if (ret)
>> + return ret;
>
> If the device supports INTx and MSI is disabled for some reason
> (booted with "pci=nomsi", ACPI_FADT_NO_MSI is set, etc), this change
> means the driver would no longer be able to fall back to using INTx.

Thanks, Bjorn

This was indeed my concern.

> If you want to go to the trouble of changing this code, you could
> consider using the new APIs:

I saw this mentioned in pci_enable_msi() kerneldoc, but didn't bring it up yet.

>
>  ret = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_ALL_TYPES);
>  if (ret < 0)
>    return ret;
>
>  if (request_threaded_irq(pdev->irq, ...)) {
>    pci_free_irq_vectors(pdev);
>    return -EIO;
>  }
>
> plus the appropriate pci_free_irq_vectors() calls in other failure and
> remove paths.
>
> See 
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/PCI/msi-howto.rst?v6.7#n93
>
>> if (request_threaded_irq(pdev->irq, brcmf_pcie_quick_check_isr,
>> brcmf_pcie_isr_thread, IRQF_SHARED,
>> "brcmf_pcie_intr", devinfo)) {
>> pci_disable_msi(pdev);
>> brcmf_err(bus, "Failed to request IRQ %d\n", pdev->irq);
>> - return -EIO;
>> + ret = -EIO;
>
> IMHO this part ("ret = -EIO" and "return ret" below) makes the code
> harder to read for no benefit.  The existing code returns -EIO
> immediately here and returns 0 below.  It's easier to read that than
> to follow the use of "ret".
>
> I guess that's just repeating what Arend already said; sorry, I hadn't
> read the whole thread yet.

No need to be sorry. Thanks for taking time to look at it and give your 
feedback.

Regards,
Arend

>
>
>> + } else {
>> + devinfo->irq_allocated = true;
>> }
>> - devinfo->irq_allocated = true;
>> - return 0;
>> + return ret;
>> }
>>
>>
>> --
>> 2.40.1


--0000000000006afb93060f5f7363
Content-Type: application/pkcs7-signature; name="smime.p7s"
Content-Transfer-Encoding: base64
Content-Disposition: attachment; filename="smime.p7s"
Content-Description: S/MIME Cryptographic Signature
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--0000000000006afb93060f5f7363--