Hi Doug, A problem related to SG_IO. When testing the 2.6.18-rc1 libata, a flood of ALLOW_MEDIUM_REMOVAL is seen after ejecting a removable disk drive: http://bugzilla.kernel.org/show_bug.cgi?id=6799 The interaction to trigger the problem is below: 1. The "eject" utility, using SG_IO, issues ALLOW_MEDIUM_REMOVAL twice to unlock the disk of the device. 2. The disk of the physical device is now unlocked, however, sdev->locked is still 1, inconsistent with the physical device status. 3. The "eject" utility ejects the disk by START_STOP_UNIT. 4. Someone issues TEST_UNIT_READY. The device is not ready since no disk inside. ATAPI check condition returned. 5. 2.6.18-rc1 libata EH triggered in SCSI EH context to request sense. 6. scsi_restart_operations(), seeing sdev->locked == 1, tries to lock the door. 7. Lock failed since no disk inside. ATAPI check condition returned. 8. 2.6.18 libata EH triggered in SCSI EH context. Goto 5 and loop forever until the disk is inserted again. It looks more like eject/scsi problem. (Libata 2.6.17 EH is not affected by the problem because the request sense is done when qc is completed, not in the SCSI EH context.) Maybe adding a filter to the SCSI SG IO layer to - Check incoming SCSI commands - Whenever ALLOW_MEDIUM_REMOVAL is seen, update the sdev->locked to make the kernel data structure consistent with the physical device status can fix the problem? -- albert - : 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