As noted in patch2:
The mmap(2) syscall suffers from the ABI anti-pattern of not validating unknown flags. However, proposals like MAP_SYNC and MAP_DIRECT need a mechanism to define new behavior that is known to fail on older kernels without the support. Define a new MAP_VALIDATE flag pattern that is guaranteed to fail on all legacy mmap implementations.
On the assumption that it is too late to finalize either MAP_SYNC or MAP_DIRECT for 4.14 inclusion I would still like to pursue getting at least patch1 in for 4.14. This allows development of these new flags for 4.15 without worrying about new ->mmap() operation instances added during the cycle. I.e. I would rebase these from v4.13-rc5 to the state of the tree right before v4.14-rc1 and re-run the Coccinelle script.
Questions:
1/ Are there any objections to MAP_VALIDATE? I think we bottomed out on the parisc compatibility concern with the realization that it is missing fundamental pmem pre-requisite features, like ZONE_DEVICE, and can otherwise define a new mmap syscall variant.
2/ Linus, are you open to taking a rebased version of patch1 late in the 4.14 window, or have a different suggestion?
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Dan Williams (2): vfs: add flags parameter to ->mmap() in 'struct file_operations' mm: introduce MAP_VALIDATE, a mechanism for for safely defining new mmap flags
arch/arc/kernel/arc_hostlink.c | 3 + arch/mips/kernel/vdso.c | 2 - arch/powerpc/kernel/proc_powerpc.c | 3 + arch/powerpc/kvm/book3s_64_vio.c | 3 + arch/powerpc/platforms/cell/spufs/file.c | 21 ++++++-- arch/powerpc/platforms/powernv/opal-prd.c | 3 + arch/um/drivers/mmapper_kern.c | 3 + drivers/android/binder.c | 3 + drivers/char/agp/frontend.c | 3 + drivers/char/bsr.c | 3 + drivers/char/hpet.c | 6 ++ drivers/char/mbcs.c | 3 + drivers/char/mbcs.h | 3 + drivers/char/mem.c | 11 +++- drivers/char/mspec.c | 9 ++-- drivers/char/uv_mmtimer.c | 6 ++ drivers/dax/device.c | 3 + drivers/dma-buf/dma-buf.c | 4 +- drivers/firewire/core-cdev.c | 3 + drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 3 + drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h | 3 + drivers/gpu/drm/amd/amdkfd/kfd_chardev.c | 5 +- drivers/gpu/drm/arc/arcpgu_drv.c | 5 +- drivers/gpu/drm/ast/ast_drv.h | 3 + drivers/gpu/drm/ast/ast_ttm.c | 3 + drivers/gpu/drm/bochs/bochs.h | 3 + drivers/gpu/drm/bochs/bochs_mm.c | 3 + drivers/gpu/drm/cirrus/cirrus_drv.h | 3 + drivers/gpu/drm/cirrus/cirrus_ttm.c | 3 + drivers/gpu/drm/drm_gem.c | 3 + drivers/gpu/drm/drm_gem_cma_helper.c | 6 ++ drivers/gpu/drm/drm_vm.c | 3 + drivers/gpu/drm/etnaviv/etnaviv_drv.h | 3 + drivers/gpu/drm/etnaviv/etnaviv_gem.c | 5 +- drivers/gpu/drm/exynos/exynos_drm_gem.c | 5 +- drivers/gpu/drm/exynos/exynos_drm_gem.h | 3 + drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_drv.h | 3 + drivers/gpu/drm/hisilicon/hibmc/hibmc_ttm.c | 3 + drivers/gpu/drm/i810/i810_dma.c | 3 + drivers/gpu/drm/i915/i915_gem_dmabuf.c | 2 - drivers/gpu/drm/mediatek/mtk_drm_gem.c | 5 +- drivers/gpu/drm/mediatek/mtk_drm_gem.h | 3 + drivers/gpu/drm/mgag200/mgag200_drv.h | 3 + drivers/gpu/drm/mgag200/mgag200_ttm.c | 3 + drivers/gpu/drm/msm/msm_drv.h | 3 + drivers/gpu/drm/msm/msm_gem.c | 5 +- drivers/gpu/drm/nouveau/nouveau_ttm.c | 5 +- drivers/gpu/drm/nouveau/nouveau_ttm.h | 2 - drivers/gpu/drm/omapdrm/omap_drv.h | 3 + drivers/gpu/drm/omapdrm/omap_gem.c | 5 +- drivers/gpu/drm/qxl/qxl_drv.h | 3 + drivers/gpu/drm/qxl/qxl_ttm.c | 3 + drivers/gpu/drm/radeon/radeon_drv.c | 3 + drivers/gpu/drm/radeon/radeon_ttm.c | 3 + drivers/gpu/drm/rockchip/rockchip_drm_gem.c | 5 +- drivers/gpu/drm/rockchip/rockchip_drm_gem.h | 3 + drivers/gpu/drm/tegra/gem.c | 5 +- drivers/gpu/drm/tegra/gem.h | 3 + drivers/gpu/drm/udl/udl_drv.h | 3 + drivers/gpu/drm/udl/udl_gem.c | 5 +- drivers/gpu/drm/vc4/vc4_bo.c | 5 +- drivers/gpu/drm/vc4/vc4_drv.h | 3 + drivers/gpu/drm/vgem/vgem_drv.c | 7 ++- drivers/gpu/drm/virtio/virtgpu_drv.h | 3 + drivers/gpu/drm/virtio/virtgpu_ttm.c | 3 + drivers/gpu/drm/vmwgfx/vmwgfx_drv.h | 3 + drivers/gpu/drm/vmwgfx/vmwgfx_ttm_glue.c | 3 + drivers/hsi/clients/cmt_speech.c | 3 + drivers/hwtracing/intel_th/msu.c | 3 + drivers/hwtracing/stm/core.c | 3 + drivers/infiniband/core/uverbs_main.c | 3 + drivers/infiniband/hw/hfi1/file_ops.c | 6 ++ drivers/infiniband/hw/qib/qib_file_ops.c | 5 +- drivers/media/v4l2-core/v4l2-dev.c | 3 + drivers/misc/aspeed-lpc-ctrl.c | 3 + drivers/misc/cxl/api.c | 5 +- drivers/misc/cxl/cxl.h | 3 + drivers/misc/cxl/file.c | 3 + drivers/misc/genwqe/card_dev.c | 3 + drivers/misc/mic/scif/scif_fd.c | 3 + drivers/misc/mic/vop/vop_vringh.c | 3 + drivers/misc/sgi-gru/grufile.c | 3 + drivers/mtd/mtdchar.c | 3 + drivers/pci/proc.c | 3 + drivers/rapidio/devices/rio_mport_cdev.c | 3 + drivers/sbus/char/flash.c | 3 + drivers/sbus/char/jsflash.c | 3 + drivers/scsi/cxlflash/superpipe.c | 5 +- drivers/scsi/sg.c | 3 + drivers/staging/android/ashmem.c | 3 + drivers/staging/comedi/comedi_fops.c | 3 + .../staging/lustre/lustre/llite/llite_internal.h | 3 + drivers/staging/lustre/lustre/llite/llite_mmap.c | 5 +- drivers/staging/vboxvideo/vbox_drv.h | 3 + drivers/staging/vboxvideo/vbox_ttm.c | 3 + drivers/staging/vme/devices/vme_user.c | 3 + drivers/uio/uio.c | 3 + drivers/usb/core/devio.c | 3 + drivers/usb/mon/mon_bin.c | 3 + drivers/vfio/vfio.c | 7 ++- drivers/video/fbdev/core/fbmem.c | 3 + drivers/video/fbdev/pxa3xx-gcu.c | 3 + drivers/xen/gntalloc.c | 3 + drivers/xen/gntdev.c | 3 + drivers/xen/privcmd.c | 3 + drivers/xen/xenbus/xenbus_dev_backend.c | 3 + drivers/xen/xenfs/xenstored.c | 3 + fs/9p/vfs_file.c | 10 ++-- fs/aio.c | 3 + fs/btrfs/file.c | 3 + fs/ceph/addr.c | 3 + fs/ceph/super.h | 3 + fs/cifs/cifsfs.h | 6 ++ fs/cifs/file.c | 10 ++-- fs/coda/file.c | 5 +- fs/ecryptfs/file.c | 5 +- fs/ext2/file.c | 5 +- fs/ext4/file.c | 3 + fs/f2fs/file.c | 3 + fs/fuse/file.c | 8 ++- fs/gfs2/file.c | 3 + fs/hugetlbfs/inode.c | 3 + fs/kernfs/file.c | 3 + fs/ncpfs/mmap.c | 3 + fs/ncpfs/ncp_fs.h | 2 - fs/nfs/file.c | 5 +- fs/nfs/internal.h | 2 - fs/nilfs2/file.c | 3 + fs/ocfs2/mmap.c | 3 + fs/ocfs2/mmap.h | 3 + fs/orangefs/file.c | 5 +- fs/proc/inode.c | 7 ++- fs/proc/vmcore.c | 6 ++ fs/ramfs/file-nommu.c | 6 ++ fs/romfs/mmap-nommu.c | 3 + fs/ubifs/file.c | 5 +- fs/xfs/xfs_file.c | 5 +- include/drm/drm_gem.h | 3 + include/drm/drm_gem_cma_helper.h | 3 + include/drm/drm_legacy.h | 3 + include/linux/fs.h | 14 ++++-- include/linux/mm.h | 2 - include/linux/mman.h | 50 ++++++++++++++++++++ include/misc/cxl.h | 3 + include/uapi/asm-generic/mman-common.h | 1 ipc/shm.c | 5 +- kernel/events/core.c | 3 + kernel/kcov.c | 3 + kernel/relay.c | 3 + mm/filemap.c | 14 ++++-- mm/mmap.c | 22 ++++++++- mm/nommu.c | 4 +- mm/shmem.c | 3 + net/socket.c | 6 ++ security/selinux/selinuxfs.c | 6 ++ sound/core/compress_offload.c | 3 + sound/core/hwdep.c | 3 + sound/core/info.c | 3 + sound/core/init.c | 3 + sound/core/oss/pcm_oss.c | 3 + sound/core/pcm_native.c | 3 + sound/oss/soundcard.c | 3 + sound/oss/swarm_cs4297a.c | 3 + virt/kvm/kvm_main.c | 3 + 164 files changed, 481 insertions(+), 231 deletions(-)