27e65621af
hrs@ and kuriyama@ have found that on some HP BIOS, a system will fail to boot immediately after installation with the claim that it can't work out which disk they are booting from. They tracked it down to a buffer overrun, and found that it could be alleviated by doing a dummy read before-hand. Submitted by: kuriyama MFC after: 1 week Differential Revision: https://reviews.freebsd.org/D14341