Re: PR kern/57833: kernel panic on xorg exit

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

Can you please try the attached patch and see if it makes progress?

I don't know if this condition should be possible, so this might be
papering over the symptom rather than addressing the problem, but
maybe it'll work as a stop-gap measure.

diff --git a/sys/external/bsd/drm2/dist/drm/i915/gem/i915_gem_mman.c b/sys/external/bsd/drm2/dist/drm/i915/gem/i915_gem_mman.c
index 8e592f008ef7..276ebbdbc234 100644
--- a/sys/external/bsd/drm2/dist/drm/i915/gem/i915_gem_mman.c
+++ b/sys/external/bsd/drm2/dist/drm/i915/gem/i915_gem_mman.c
@@ -677,6 +677,8 @@ void i915_gem_object_release_mmap_offset(struct drm_i915_gem_object *obj)
 		return;
 	for (i = 0; i < obj->base.size >> PAGE_SHIFT; i++) {
 		page = obj->mm.pages->sgl->sg_pgs[i];
+		if (page == NULL)
+			continue;
 		vm_page = &page->p_vmp;
 		pmap_page_protect(vm_page, VM_PROT_NONE);
 	}