Index: head/usr.sbin/bhyve/pci_virtio_block.c
===================================================================
--- head/usr.sbin/bhyve/pci_virtio_block.c
+++ head/usr.sbin/bhyve/pci_virtio_block.c
@@ -523,7 +523,7 @@
 	sc->vbsc_cfg.vbc_writeback = 0;
 	sc->vbsc_cfg.max_discard_sectors = VTBLK_MAX_DISCARD_SECT;
 	sc->vbsc_cfg.max_discard_seg = VTBLK_MAX_DISCARD_SEG;
-	sc->vbsc_cfg.discard_sector_alignment = sectsz / VTBLK_BSIZE;
+	sc->vbsc_cfg.discard_sector_alignment = MAX(sectsz, sts) / VTBLK_BSIZE;
 
 	/*
 	 * Should we move some of this into virtio.c?  Could