On Thu, 14 Jan 2010 10:54:44 GMT bugzilla-daemon@xxxxxxxxxxxxxxxxxxx wrote: > http://bugzilla.kernel.org/show_bug.cgi?id=15007 > > > > > > --- Comment #2 from nick cheng <nick.cheng@xxxxxxxxxxxx> 2010-01-14 10:54:42 --- > Thanks for reply. > I am sure that hardware and firmware can handle 1024 scatter gather > entries. > I can not limit the AP to dispatch a write command with 128 sg entries. > I just execute mkfs.ext3 /dev/sdX and print it out as the sg entry number is > 128. I found the 128th entry indeed has no data. So 'no data sg entry' is the cause of hardware reset? >From a quick look at the driver, I found one bug about scatter-gather handling. static int arcmsr_build_ccb(struct AdapterControlBlock *acb,struct CommandControlBlock *ccb,struct scsi_cmnd *pcmd) { (snip)... arccdbsize += sizeof(struct SG32ENTRY); }else{ struct SG64ENTRY *pdma_sg = (struct SG64ENTRY *)psge; pdma_sg->addresshigh = address_hi; pdma_sg->address = address_lo; pdma_sg->length = length|cpu_to_le32(IS_SG64_ADDR); psge += sizeof(struct SG64ENTRY); arccdbsize += sizeof(struct SG64ENTRY); } sl++; The last line doesn't work. Use sl = sg_next(sl); Using scsi_for_each_sg() is even better (as the driver in mainline does). With this bug, 129th sg entry is broken. If your analysis is correct, there should be other bugs.. -- 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
