On Wed, 13 Mar 2024, Simon Guinot wrote:
> The current code in pcie_wait_for_link_delay() handles the value
> returned by pcie_failed_link_retrain() as an integer, expecting 0
> when the link has been successfully retrained. The issue is that
> pcie_failed_link_retrain() returns a boolean: "true" if the link
> has been successfully retrained and "false" otherwise. This leads
> pcie_wait_for_link_delay() to return an incorrect "active link"
> status when pcie_failed_link_retrain() is called.
>
> This patch fixes the check of the value returned by
> pcie_failed_link_retrain() in pcie_wait_for_link_delay().
>
> Note that this bug induces abnormal timeout delays when a PCI device
> is unplugged (around 60 seconds per bridge / secondary bus removed).
>
> Cc: [email protected]
> Fixes: 1abb47390350 ("Merge branch 'pci/enumeration'")
> Signed-off-by: Simon Guinot <[email protected]>
Hi Simon,
Thanks for your patch. There's, however, already a better series to fix
this and other related issues. Bjorn just hasn't gotten into applying them
yet:
https://patchwork.kernel.org/project/linux-pci/list/?series=824858
(I proposed a patch very similar to yours month ago, but Maciej came up
a better way to fix all the issues.)
--
i.
> ---
> drivers/pci/pci.c | 4 +---
> 1 file changed, 1 insertion(+), 3 deletions(-)
>
> diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
> index ccee56615f78..7ec91b4c5d03 100644
> --- a/drivers/pci/pci.c
> +++ b/drivers/pci/pci.c
> @@ -5101,9 +5101,7 @@ static bool pcie_wait_for_link_delay(struct pci_dev *pdev, bool active,
> msleep(20);
> rc = pcie_wait_for_link_status(pdev, false, active);
> if (active) {
> - if (rc)
> - rc = pcie_failed_link_retrain(pdev);
> - if (rc)
> + if (rc && !pcie_failed_link_retrain(pdev))
> return false;
>
> msleep(delay);
>
--
i.
On Wed, Mar 13, 2024 at 02:00:21PM +0200, Ilpo Järvinen wrote:
> On Wed, 13 Mar 2024, Simon Guinot wrote:
>
> > The current code in pcie_wait_for_link_delay() handles the value
> > returned by pcie_failed_link_retrain() as an integer, expecting 0
> > when the link has been successfully retrained. The issue is that
> > pcie_failed_link_retrain() returns a boolean: "true" if the link
> > has been successfully retrained and "false" otherwise. This leads
> > pcie_wait_for_link_delay() to return an incorrect "active link"
> > status when pcie_failed_link_retrain() is called.
> >
> > This patch fixes the check of the value returned by
> > pcie_failed_link_retrain() in pcie_wait_for_link_delay().
> >
> > Note that this bug induces abnormal timeout delays when a PCI device
> > is unplugged (around 60 seconds per bridge / secondary bus removed).
> >
> > Cc: [email protected]
> > Fixes: 1abb47390350 ("Merge branch 'pci/enumeration'")
> > Signed-off-by: Simon Guinot <[email protected]>
>
> Hi Simon,
>
> Thanks for your patch. There's, however, already a better series to fix
> this and other related issues. Bjorn just hasn't gotten into applying them
> yet:
>
> https://patchwork.kernel.org/project/linux-pci/list/?series=824858
>
> (I proposed a patch very similar to yours month ago, but Maciej came up
> a better way to fix all the issues.)
Hi Ilpo,
Thanks for pointing this patch series. This indeed fixes the timeout delay
issue I observed.
Simon