On 11/10/12 11:24, James Bottomley wrote: > On Thu, 2012-10-11 at 10:15 +0100, James Hogan wrote: >> The struct scsi_varlen_cdb_hdr is expected to be exactly 10 bytes when >> used in struct osd_cdb_head, but it isn't marked as packed. Some >> architectures will round the struct size up which triggers BUILD_BUG_ON >> compile errors in osd_initiator.c when the outer structs are unexpected >> sizes. This is fixed by marking struct scsi_varlen_cdb_hdr as __packed. > > What actual problem have you encountered? The structure is {u8[8], u16} > which is naturally packed on every architecture I know about. I've even > built osd_initiator without problem on parisc, which has some of the > most rigid alignment rules I've seen. Hi James, The alignment is fine (the offset of the u16 is 8 bytes), but unfortunately with the metag port of gcc, sizeof(struct scsi_varlen_cdb_hdr) is rounded up to a 4 byte boundary (even though the largest data member alignment is only 2 bytes), which is 12 bytes instead of 10. Cheers James -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html