Re: [PATCH v4] iommu/of: Fix pci_request_acs() before enumerating PCI devices

[Joerg Roedel]

On Fri, May 21, 2021 at 03:03:24AM +0000, Wang Xingang wrote:
> From: Xingang Wang <wangxingang5@xxxxxxxxxx>
> 
> When booting with devicetree, the pci_request_acs() is called after the
> enumeration and initialization of PCI devices, thus the ACS is not
> enabled. And ACS should be enabled when IOMMU is detected for the
> PCI host bridge, so add check for IOMMU before probe of PCI host and call
> pci_request_acs() to make sure ACS will be enabled when enumerating PCI
> devices.
> 
> Fixes: 6bf6c24720d33 ("iommu/of: Request ACS from the PCI core when
> configuring IOMMU linkage")
> Signed-off-by: Xingang Wang <wangxingang5@xxxxxxxxxx>
> ---
>  drivers/iommu/of_iommu.c | 1 -
>  drivers/pci/of.c         | 8 +++++++-
>  2 files changed, 7 insertions(+), 2 deletions(-)

Should probably go through the PCI tree, so

Acked-by: Joerg Roedel <jroedel@xxxxxxx>