Hi!
drivers/gpu/drm/radeon/radeon_kns.c: static int radeon_info_ioctl(...)
...
value_ptr = (uint32_t *)((unsigned long)info->value);
// value_ptr = (uint32_t __user *)(info->value); // looks like more
correct for x86_64
...
if (copy_to_user(value_ptr, (char*)value, value_size)) {...
Why value_ptr is assumed to be lower 4 Gb?