On Mon, 19 Dec 2022 13:42:06 -0500
Steven Sistare <steven.sistare@xxxxxxxxxx> wrote:
> Alex, Jason, any comments before I post the (hopefully final) version?
I like Kevin's comments, nothing additional from me. Thanks,
Alex
> On 12/16/2022 1:50 PM, Steve Sistare wrote:
> > Fix bugs in the interfaces that allow the underlying memory object of an
> > iova range to be mapped in a new address space. They allow userland to
> > indefinitely block vfio mediated device kernel threads, and do not
> > propagate the locked_vm count to a new mm. Also fix a pre-existing bug
> > that allows locked_vm underflow.
> >
> > The fixes impose restrictions that eliminate waiting conditions, so
> > revert the dead code:
> > commit 898b9eaeb3fe ("vfio/type1: block on invalid vaddr")
> > commit 487ace134053 ("vfio/type1: implement notify callback")
> > commit ec5e32940cc9 ("vfio: iommu driver notify callback")
> >
> > Changes in V2 (thanks Alex):
> > * do not allow group attach while vaddrs are invalid
> > * add patches to delete dead code
> > * add WARN_ON for never-should-happen conditions
> > * check for changed mm in unmap.
> > * check for vfio_lock_acct failure in remap
> >
> > Changes in V3 (ditto!):
> > * return errno at WARN_ON sites, and make it unique
> > * correctly check for dma task mm change
> > * change dma owner to current when vaddr is updated
> > * add Fixes to commit messages
> > * refactored new code in vfio_dma_do_map
> >
> > Changes in V4:
> > * misc cosmetic changes
> >
> > Changes in V5 (thanks Jason and Kevin):
> > * grab mm and use it for locked_vm accounting
> > * separate patches for underflow and restoring locked_vm
> > * account for reserved pages
> > * improve error messages
> >
> > Changes in V6:
> > * drop "count reserved pages" patch
> > * add "track locked_vm" patch
> > * grab current->mm not group_leader->mm
> > * simplify vfio_change_dma_owner
> > * fix commit messages
> >
> > Steve Sistare (7):
> > vfio/type1: exclude mdevs from VFIO_UPDATE_VADDR
> > vfio/type1: prevent underflow of locked_vm via exec()
> > vfio/type1: track locked_vm per dma
> > vfio/type1: restore locked_vm
> > vfio/type1: revert "block on invalid vaddr"
> > vfio/type1: revert "implement notify callback"
> > vfio: revert "iommu driver notify callback"
> >
> > drivers/vfio/container.c | 5 -
> > drivers/vfio/vfio.h | 7 --
> > drivers/vfio/vfio_iommu_type1.c | 226 ++++++++++++++++++----------------------
> > include/uapi/linux/vfio.h | 15 +--
> > 4 files changed, 111 insertions(+), 142 deletions(-)
> >
>
