Hi DRM Devs,
In commit 7661809d493b ("mm: don't allow oversized kvmalloc() calls") from July, Linus added a WARN_ONCE() for "crazy" allocations over 2GB. I have a static checker warning for this and most of the warnings are from DRM ioctls.
drivers/gpu/drm/lima/lima_drv.c:124 lima_ioctl_gem_submit() warn: uncapped user size for kvmalloc() will WARN drivers/gpu/drm/radeon/radeon_cs.c:291 radeon_cs_parser_init() warn: uncapped user size for kvmalloc() will WARN drivers/gpu/drm/v3d/v3d_gem.c:311 v3d_lookup_bos() warn: uncapped user size for kvmalloc() will WARN drivers/gpu/drm/v3d/v3d_gem.c:319 v3d_lookup_bos() warn: uncapped user size for kvmalloc() will WARN drivers/gpu/drm/v3d/v3d_gem.c:601 v3d_get_multisync_post_deps() warn: uncapped user size for kvmalloc() will WARN drivers/gpu/drm/etnaviv/etnaviv_gem_submit.c:476 etnaviv_ioctl_gem_submit() warn: uncapped user size for kvmalloc() will WARN drivers/gpu/drm/etnaviv/etnaviv_gem_submit.c:477 etnaviv_ioctl_gem_submit() warn: uncapped user size for kvmalloc() will WARN drivers/gpu/drm/etnaviv/etnaviv_gem_submit.c:478 etnaviv_ioctl_gem_submit() warn: uncapped user size for kvmalloc() will WARN drivers/gpu/drm/etnaviv/etnaviv_gem_submit.c:479 etnaviv_ioctl_gem_submit() warn: uncapped user size for kvmalloc() will WARN drivers/gpu/drm/virtio/virtgpu_ioctl.c:186 virtio_gpu_execbuffer_ioctl() warn: uncapped user size for kvmalloc() will WARN drivers/gpu/drm/panfrost/panfrost_drv.c:198 panfrost_copy_in_sync() warn: uncapped user size for kvmalloc() will WARN drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c:120 amdgpu_cs_parser_init() warn: uncapped user size for kvmalloc() will WARN
These ioctls can all trigger the stack dump. The line numbers are from linux next (next-20211214).
I feel like ideally if this could be fixed in a central way, but if not then hopefully I've added the relevant lists to the CC.
regards, dan carpenter