Re: [PATCH v2 3/3] vfio/pci: Enable PCI resource mmap() on s390 and remove VFIO_PCI_MMAP

From: Jason Gunthorpe
Date: Thu May 23 2024 - 11:19:42 EST


On Thu, May 23, 2024 at 01:10:16PM +0200, Niklas Schnelle wrote:
> With the introduction of memory I/O (MIO) instructions enbaled in commit
> 71ba41c9b1d9 ("s390/pci: provide support for MIO instructions") s390
> gained support for direct user-space access to mapped PCI resources.
> Even without those however user-space can access mapped PCI resources
> via the s390 specific MMIO syscalls. Thus mmap() can and should be
> supported on all s390 systems with native PCI. Since VFIO_PCI_MMAP
> enablement for s390 would make it unconditionally true and thus
> pointless just remove it entirely.
>
> Link: https://lore.kernel.org/all/c5ba134a1d4f4465b5956027e6a4ea6f6beff969.camel@xxxxxxxxxxxxx/
> Suggested-by: Jason Gunthorpe <jgg@xxxxxxxxxx>
> Signed-off-by: Niklas Schnelle <schnelle@xxxxxxxxxxxxx>
> ---
> drivers/vfio/pci/Kconfig | 4 ----
> drivers/vfio/pci/vfio_pci_core.c | 3 ---
> 2 files changed, 7 deletions(-)

Reviewed-by: Jason Gunthorpe <jgg@xxxxxxxxxx>

Jason