CVS commit: src/sys/external/bsd/drm2/dist/drm/i915/gem

["Taylor R Campbell" <riastradh%netbsd.org@localhost>]

Module Name:    src
Committed By:   riastradh
Date:           Fri Jan 19 22:23:04 UTC 2024

Modified Files:
        src/sys/external/bsd/drm2/dist/drm/i915/gem: i915_gem_phys.c

Log Message:
i915_gem_phys: Fill sg_pgs.

This is needed by i915 gem fault, which maps user virtual addresses
to those pages, and by i915 gem object destruction, which does
pmap_page_protect on the pages to remove any of those user virtual
mappings.

This needs pmap_kenter_pa rather than pmap_enter(pmap_kernel(), ...)
in order to preserve the _kernel's_ mapping of the pages after
pmap_page_protect.

But bus_dmamem_map currently uses pmap_enter(pmap_kernel(), ...)
instead which creates a mapping that is removed by pmap_page_protect.

So we use a variant of bus_dmamem_map that uses pmap_kenter_pa
instead.  Perhaps bus_dmamem_map should do this itself, but this
change is less risky to pull up than a change to bus_dmamem_map
itself.

PR kern/57833: kernel panic on xorg exit

XXX pullup-10


To generate a diff of this commit:
cvs rdiff -u -r1.8 -r1.9 \
    src/sys/external/bsd/drm2/dist/drm/i915/gem/i915_gem_phys.c

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.