On 8/13/25 1:06 PM, Keith Busch wrote:
But I can't make that change because many scsi devices don't set the dma alignment and get the default 511 value. This is fine for the memory address offset, but the lengths sent for various inquriy commands are much smaller, like 4 and 32 byte lengths. That length wouldn't pass the dma alignment granularity, so I think the default value is far too conservative. Does the address start size need to be a different limit than minimum length? I feel like they should be the same, but maybe that's just an nvme thing.
Hi Keith, Maybe I misunderstood your question. It seems to me that the SCSI core sets the DMA alignment by default to four bytes. From drivers/scsi/hosts.c: /* 32-byte (dword) is a common minimum for HBAs. */ if (sht->dma_alignment) shost->dma_alignment = sht->dma_alignment; else shost->dma_alignment = 3; Bart.
