I ran into a segmentation fault a week ago.
And I finally found that the function vkCreateRayTracingPipelinesKHR will cause a segmentation fault (probably from the user level driver?) if the supplied shader modules do not include any callable shader / shader group but there is an OpExecuteCallableKHR instruction inside any of the shader modules (raygen, chit, etc), even if this command is not going to be actually executed on the GPU. I solved this by creating an idle callable before assembling the raytracing pipelines.
I haven’t found anyone ran into the same problem and posted that online. So I’ll post this in hope of saving another random programmer’s time. It took me a week to discover and reproduce this behavior, and it is really exhausting and frustrating trying to find the cause for the mysterious crash when the validation layer & driver gives me no infomation to debug.