Hi guys, While the hotplug is now far more reliable, I have recently been able to coax it into locking up SATA ports again while the device is heavily loaded. This looks very similar to the previous lockups, with the SATA port left frozen. I have pasted some tracing below; at the end of the trace ata4 is no longer responsive to hotplug events. I have attempted to add further tracing to find out where the freeze is occurring, but so far this has just prevented me from triggering the condition. I am currently trying to locate the problem by inspecting the sources, but you may have some intuition that could shortcut my efforts. I should mention that we are now working on kernel 2.6.39.4 (and are choosing not to go with 3.x to limit changes as we progress towards final testing.) Kind Regards, Bruce. [...] ata4.00: configured for UDMA/33 ata_eh_recover: EXIT, rc=0 ata4: EH complete ata_scsi_error: EXIT ata_scsiop_noop: ENTER ata_scsiop_read_cap: ENTER ata_scsiop_mode_sense: ENTER ata_scsiop_mode_sense: ENTER ata_scsiop_mode_sense: ENTER __ata_port_freeze: ata4 port frozen ata_scsi_timed_out: ENTER ata_scsi_timed_out: EXIT, ret=0 ata_scsi_error: ENTER ata_sff_flush_pio_task: ENTER ata_eh_link_autopsy: ENTER ata_eh_link_autopsy: EXIT ata4.00: exception Emask 0x10 SAct 0x0 SErr 0x190002 action 0xe frozen ata4.00: edma_err_cause=00000020 pp_flags=00000000, SError=00180000 ata4: SError: { RecovComm PHYRdyChg 10B8B Dispar } ata4.00: failed command: FLUSH CACHE EXT ata4.00: cmd ea/00:00:00:00:00/00:00:00:00:00/a0 tag 0 res 50/00:00:30:5a:27/00:08:00:00:00/a0 Emask 0x10 (ATA bus error) ata4.00: status: { DRDY } ata_eh_recover: ENTER __ata_port_freeze: ata4 port frozen ata4: hard resetting link sata_link_hardreset: ENTER sata_link_hardreset: EXIT, rc=0 ata_sff_softreset: ENTER ata_sff_softreset: about to softreset, devmask=1 ata_bus_softreset: ata4: bus reset via SRST ata_dev_classify: found ATA device by sig ata_sff_softreset: EXIT, classes[0]=1 [1]=0 ata_eh_thaw_port: ata4 port thawed ata_std_postreset: ENTER ata4: SATA link up 1.5 Gbps (SStatus 113 SControl 310) ata_std_postreset: EXIT ata_eh_revalidate_and_attach: ENTER ata_sff_flush_pio_task: ENTER ata_sff_flush_pio_task: ENTER ata_dump_id: 49==0x2f00 53==0x0007 63==0x0007 64==0x0003 75==0x001f ata_dump_id: 80==0x01f0 81==0x0029 82==0x346b 83==0x7d61 84==0x4133 ata_dump_id: 88==0x047f 93==0x0000 ata_dev_set_xfermode: set features - xfer mode ata_sff_flush_pio_task: ENTER ata_dev_set_xfermode: EXIT, err_mask=0 ata_sff_flush_pio_task: ENTER ata_sff_flush_pio_task: ENTER ata_dump_id: 49==0x2f00 53==0x0007 63==0x0007 64==0x0003 75==0x001f ata_dump_id: 80==0x01f0 81==0x0029 82==0x346b 83==0x7d61 84==0x4133 ata_dump_id: 88==0x047f 93==0x0000 ata_dev_set_mode: xfer_shift=12, xfer_mode=0x42 ata4.00: configured for UDMA/33 ata4.00: retrying FLUSH 0xea Emask 0x10 ata_sff_flush_pio_task: ENTER ata_eh_recover: EXIT, rc=0 ata4: EH complete ata_scsi_error: EXIT __ata_port_freeze: ata4 port frozen ata_port_schedule_eh: port EH scheduled ata_scsiop_noop: ENTER ata_scsiop_read_cap: ENTER ata_scsiop_mode_sense: ENTER ata_scsiop_mode_sense: ENTER ata_scsiop_mode_sense: ENTER Latest News at: http://www.indigovision.com/index.php/en/news.html -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html