linux-kernel - Re: [RESEND v3 5/5] PCI: dwc: Don't return error when wait for link up

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20250818153224.GA527775@bhelgaas>
Date: Mon, 18 Aug 2025 10:32:24 -0500
From: Bjorn Helgaas <helgaas@...nel.org>
To: Richard Zhu <hongxing.zhu@....com>
Cc: frank.li@....com, jingoohan1@...il.com, l.stach@...gutronix.de,
	lpieralisi@...nel.org, kwilczynski@...nel.org, mani@...nel.org,
	robh@...nel.org, bhelgaas@...gle.com, shawnguo@...nel.org,
	s.hauer@...gutronix.de, kernel@...gutronix.de, festevam@...il.com,
	linux-pci@...r.kernel.org, linux-arm-kernel@...ts.infradead.org,
	imx@...ts.linux.dev, linux-kernel@...r.kernel.org
Subject: Re: [RESEND v3 5/5] PCI: dwc: Don't return error when wait for link
 up

On Mon, Aug 18, 2025 at 03:32:05PM +0800, Richard Zhu wrote:
> When waiting for the PCIe link to come up, both link up and link down
> are valid results depending on the device state. Do not return an error,
> as the outcome has already been reported in dw_pcie_wait_for_link().

The reporting in dw_pcie_wait_for_link() is only a note in dmesg (and
the -EDTIMEDOUT return, which we're throwing away here).

We need an explanation here about why the caller of
dw_pcie_resume_noirq() doesn't need to know whether the link came up.
A short comment in the code would be useful as well.

> Signed-off-by: Richard Zhu <hongxing.zhu@....com>
> Reviewed-by: Frank Li <Frank.Li@....com>
> ---
>  drivers/pci/controller/dwc/pcie-designware-host.c | 4 +---
>  1 file changed, 1 insertion(+), 3 deletions(-)
> 
> diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c
> index 868e7db4e3381..e90fd34925702 100644
> --- a/drivers/pci/controller/dwc/pcie-designware-host.c
> +++ b/drivers/pci/controller/dwc/pcie-designware-host.c
> @@ -1089,9 +1089,7 @@ int dw_pcie_resume_noirq(struct dw_pcie *pci)
>  	if (ret)
>  		return ret;
>  
> -	ret = dw_pcie_wait_for_link(pci);
> -	if (ret)
> -		return ret;
> +	dw_pcie_wait_for_link(pci);
>  
>  	return ret;

This should be "return 0" because if "ret" was non-zero, we returned
that earlier.

>  }
> -- 
> 2.37.1
>