Re: [PATCH v3] fs/fat/fat.c: Do not perform zero block reads if there are no blocks left

On Tue, Jun 23, 2020 at 02:36:54PM -0700, Jason Wessel wrote:

While using u-boot with qemu's virtio driver I stumbled across a problem reading files less than sector size. On the real hardware the block reader seems ok with reading zero blocks, and while we could fix the virtio host side of qemu to deal with a zero block read instead of crashing, the u-boot fat driver should not be doing zero block reads in the first place. If you ask hardware to read zero blocks you are just going to get zero data. There may also be other hardware that responds similarly to the virtio interface so this is worth fixing.

Without the patch I get the following and have to restart qemu because it dies.

Applied to u-boot/master, thanks!