Re: [PATCH v3 0/2] avoid inserting duplicate IDs in dynids list

[Bjorn Helgaas]

On Tue, Nov 17, 2020 at 01:44:07PM +0800, Zhenzhong Duan wrote:
> vfio-pci and pci-stub use new_id to bind devices. But one can add same IDs
> multiple times, for example:
> 
> # echo "1af4 1041" > /sys/bus/pci/drivers/vfio-pci/new_id
> # echo "1af4 1041" > /sys/bus/pci/drivers/vfio-pci/new_id
> # echo "1af4 1041" > /sys/bus/pci/drivers/vfio-pci/new_id
> # echo "1af4 1041" > /sys/bus/pci/drivers/vfio-pci/remove_id
> # echo "1af4 1041" > /sys/bus/pci/drivers/vfio-pci/remove_id
> # echo "1af4 1041" > /sys/bus/pci/drivers/vfio-pci/remove_id
> # echo "1af4 1041" > /sys/bus/pci/drivers/vfio-pci/remove_id
> -bash: echo: write error: No such device
> 
> This doesn't cause user-visible broken behavior, but not user friendly.
> he has to remove same IDs same times to ensure it's completely gone.
> 
> Changed to only allow one dynamic entry of the same kind, after fix:
> 
> # echo "1af4 1041" > /sys/bus/pci/drivers/vfio-pci/new_id
> # echo "1af4 1041" > /sys/bus/pci/drivers/vfio-pci/new_id
> -bash: echo: write error: File exists
> # echo "1af4 1041" > /sys/bus/pci/drivers/vfio-pci/remove_id
> # echo "1af4 1041" > /sys/bus/pci/drivers/vfio-pci/remove_id
> -bash: echo: write error: No such device
> 
> 
> v3: add a separate patch to process dependency issue per Bjorn
>     make commit log more clear per Bjorn
> v2: revert the export of pci_match_device() per Christoph
>     combind PATCH1 and PATCH2 into one.
> 
> v2 link:https://lkml.org/lkml/2020/10/25/347
> 
> Zhenzhong Duan (2):
>   PCI: move pci_match_device() ahead of new_id_store()
>   PCI: avoid duplicate IDs in dynamic IDs list
> 
>  drivers/pci/pci-driver.c | 146 +++++++++++++++++++++++------------------------
>  1 file changed, 73 insertions(+), 73 deletions(-)
> 
> -- 
> 1.8.3.1
> 
> 
> Zhenzhong Duan (2):
>   PCI: move pci_match_device() ahead of new_id_store()
>   PCI: avoid duplicate IDs in dynamic IDs list
> 
>  drivers/pci/pci-driver.c | 146 +++++++++++++++++++++++------------------------
>  1 file changed, 73 insertions(+), 73 deletions(-)

I corrected the subject lines:

  PCI: Move pci_match_device() ahead of new_id_store()
  PCI: Avoid duplicate IDs in driver dynamic IDs list

and applied both to pci/enumeration for v5.11, thanks!