Mark Lord wrote:
Got your attention now? Good! I am doing some testing with known-bad drives on 2.6.16 (and 2.6.17). Libata EH is wretched there, because it does not seem to be careful about reading/saving the bad ata_status value when an error occurs. The ata_status from a failed/aborted command is first read in the interrupt handler, either by the LLD or by ata_host_intr(). This value is not saved for reuse anywhere, and the next time it is read, the reader will see ATA_ERR==0, and then not do the Right Thing (tm). Who reads it next, you ask? Well, it gets read *again* from libata-scsi when it is trying to generate meaningful sense data. But at that point, all that is seen is 0x50 -- "success". So libata-scsi returns incorrect (or no) sense data to the SCSI mid-layer, and the error is mishandled or ignored. Ugh. The distro folks will probably want to fix this in their 2.6.1[56] based distro kernels. I don't yet see a way to do this without modifying core data structures (eg. adding an ata_status field to the qc).
What driver? What architecture? What kernel config? How does 2.6.18-rc1, with vastly different EH, behave? Jeff - : 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
