lkml.org 
[lkml]   [2012]   [Mar]   [27]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] ASPM: Fix pcie devices with non-pcie children
On 27/03/12 15:17, Matthew Garrett wrote:
> Commit 4949be16822e92a18ea0cc1616319926628092ee changed the behaviour of
> pcie_aspm_sanity_check() to always return 0 if aspm is disabled, in order
> to avoid cases where we changed ASPM state on pre-PCIe 1.1 devices. This
> skipped the secondary function of pcie_aspm_sanity_check which was to avoid
> us enabling ASPM on devices that had non-PCIe children, causing us to hit
> a BUG_ON later on. Move the aspm_disabled check so we continue to honour
> that scenario.
>
> Signed-off-by: Matthew Garrett<mjg@redhat.com>
> Cc: stable@vger.kernel.org
> ---
> drivers/pci/pcie/aspm.c | 13 ++++++++++---
> 1 files changed, 10 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c
> index 86111d9..41e367b 100644
> --- a/drivers/pci/pcie/aspm.c
> +++ b/drivers/pci/pcie/aspm.c
> @@ -521,9 +521,6 @@ static int pcie_aspm_sanity_check(struct pci_dev *pdev)
> int pos;
> u32 reg32;
>
> - if (aspm_disabled)
> - return 0;
> -
> /*
> * Some functions in a slot might not all be PCIe functions,
> * very strange. Disable ASPM for the whole slot
> @@ -532,6 +529,16 @@ static int pcie_aspm_sanity_check(struct pci_dev *pdev)
> pos = pci_pcie_cap(child);
> if (!pos)
> return -EINVAL;
> +
> + /*
> + * If ASPM is disabled then we're not going to change
> + * the BIOS state. It's safe to continue even if it's a
> + * pre-1.1 device
> + */
> +
> + if (aspm_disabled)
> + continue;
> +
> /*
> * Disable ASPM for pre-1.1 PCIe device, we follow MS to use
> * RBER bit to determine if a function is 1.1 version device

We got a user who's now verified this fixes the BUG_ON() during boot,
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/961482/comments/51

.. so this does the trick. Thanks Matthew.


\
 
 \ /
  Last update: 2012-03-27 19:01    [W:0.055 / U:1.240 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site