[v2,00/17] follow_pfn and other iomap races

Message

Daniel Vetter Oct. 9, 2020, 7:59 a.m. UTC

Hi all,

Round two of my patch series to clamp down a bunch of races and gaps
around follow_pfn and other access to iomem mmaps. Previous version:

v1: https://lore.kernel.org/dri-devel/[e-mail]/

And the discussion that sparked this journey:

https://lore.kernel.org/dri-devel/[e-mail]/

Changes in v2:
- tons of small polish&fixes all over, thanks to all the reviewers who
  spotted issues
- I managed to test at least the generic_access_phys and pci mmap revoke
  stuff with a few gdb sessions using our i915 debug tools (hence now also
  the drm/i915 patch to properly request all the pci bar regions)
- reworked approach for the pci mmap revoke: Infrastructure moved into
  kernel/resource.c, address_space mapping is now set up at open time for
  everyone (which required some sysfs changes). Does indeed look a lot
  cleaner and a lot less invasive than I feared at first.

The big thing I can't test are all the frame_vector changes in habanalbas,
exynos and media. Gerald has given the s390 patch a spin already.

Review, testing, feedback all very much welcome.

Cheers, Daniel

Daniel Vetter (17):
  drm/exynos: Stop using frame_vector helpers
  drm/exynos: Use FOLL_LONGTERM for g2d cmdlists
  misc/habana: Stop using frame_vector helpers
  misc/habana: Use FOLL_LONGTERM for userptr
  mm/frame-vector: Use FOLL_LONGTERM
  media: videobuf2: Move frame_vector into media subsystem
  mm: Close race in generic_access_phys
  s390/pci: Remove races against pte updates
  mm: Add unsafe_follow_pfn
  media/videbuf1|2: Mark follow_pfn usage as unsafe
  vfio/type1: Mark follow_pfn as unsafe
  PCI: Obey iomem restrictions for procfs mmap
  /dev/mem: Only set filp->f_mapping
  resource: Move devmem revoke code to resource framework
  sysfs: Support zapping of binary attr mmaps
  PCI: Revoke mappings like devmem
  drm/i915: Properly request PCI BARs

 arch/s390/pci/pci_mmio.c                      | 98 +++++++++++--------
 drivers/char/mem.c                            | 86 +---------------
 drivers/gpu/drm/exynos/Kconfig                |  1 -
 drivers/gpu/drm/exynos/exynos_drm_g2d.c       | 48 ++++-----
 drivers/gpu/drm/i915/intel_uncore.c           | 25 ++++-
 drivers/media/common/videobuf2/Kconfig        |  1 -
 drivers/media/common/videobuf2/Makefile       |  1 +
 .../media/common/videobuf2}/frame_vector.c    | 54 ++++------
 drivers/media/platform/omap/Kconfig           |  1 -
 drivers/media/v4l2-core/videobuf-dma-contig.c |  2 +-
 drivers/misc/habanalabs/Kconfig               |  1 -
 drivers/misc/habanalabs/common/habanalabs.h   |  3 +-
 drivers/misc/habanalabs/common/memory.c       | 50 ++++------
 drivers/pci/pci-sysfs.c                       |  4 +
 drivers/pci/proc.c                            |  6 ++
 drivers/vfio/vfio_iommu_type1.c               |  4 +-
 fs/sysfs/file.c                               | 11 +++
 include/linux/ioport.h                        |  6 +-
 include/linux/mm.h                            | 47 +--------
 include/linux/sysfs.h                         |  2 +
 include/media/videobuf2-core.h                | 42 ++++++++
 kernel/resource.c                             | 95 +++++++++++++++++-
 mm/Kconfig                                    |  3 -
 mm/Makefile                                   |  1 -
 mm/memory.c                                   | 76 +++++++++++++-
 mm/nommu.c                                    | 17 ++++
 security/Kconfig                              | 13 +++
 27 files changed, 412 insertions(+), 286 deletions(-)
 rename {mm => drivers/media/common/videobuf2}/frame_vector.c (85%)