[PATCH v4 00/15] follow_pfn and other iomap races

From: Daniel Vetter
Date: Mon Oct 26 2020 - 06:58:37 EST


Hi all

Round 3 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/20201007164426.1812530-1-daniel.vetter@xxxxxxxx/
v2: https://lore.kernel.org/dri-devel/20201009075934.3509076-1-daniel.vetter@xxxxxxxx
v3: https://lore.kernel.org/dri-devel/20201021085655.1192025-1-daniel.vetter@xxxxxxxx/

And the discussion that sparked this journey:

https://lore.kernel.org/dri-devel/20201007164426.1812530-1-daniel.vetter@xxxxxxxx/

Changes in v4:
- Drop the s390 patch, that was very stand-alone and now queued up to land
through s390 trees.
- Comment polish per Dan's review.

Changes in v3:
- Bunch of polish all over, no functional changes aside from one barrier
in the resource code, for consistency.
- A few more r-b tags.

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.

I feel like this is ready for some wider soaking. Since the remaining bits
are all kinda connnected probably simplest if it all goes through -mm.

Cheers, Daniel

Daniel Vetter (15):
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
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

drivers/char/mem.c | 86 +--------------
drivers/gpu/drm/exynos/Kconfig | 1 -
drivers/gpu/drm/exynos/exynos_drm_g2d.c | 48 ++++-----
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 | 6 +-
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/frame_vector.h | 47 ++++++++
include/media/videobuf2-core.h | 1 +
kernel/resource.c | 101 +++++++++++++++++-
mm/Kconfig | 3 -
mm/Makefile | 1 -
mm/memory.c | 78 +++++++++++++-
mm/nommu.c | 17 +++
security/Kconfig | 13 +++
26 files changed, 347 insertions(+), 245 deletions(-)
rename {mm => drivers/media/common/videobuf2}/frame_vector.c (85%)
create mode 100644 include/media/frame_vector.h

--
2.28.0