https://bugzilla.kernel.org/show_bug.cgi?id=200709 Bug ID: 200709 Summary: QEMU's IDE hard disk device fails to work properly with 4.18 release candidates (regression vs. 4.17 and earlier) Product: IO/Storage Version: 2.5 Kernel Version: 4.18-rc7 Hardware: i386 OS: Linux Tree: Mainline Status: NEW Severity: high Priority: P1 Component: IDE Assignee: io_ide@xxxxxxxxxxxxxxxxxxxx Reporter: david@xxxxxxxxxxxxx Regression: No With kernels 4.18 RC4 through RC7 (RC4 is the farthest back I've tested), QEMU's IDE hard disk device fails to work properly (dmesg excerpt follows), resulting in VMs that cannot boot. This is not an issue with any stable kernel releases, e.g. 4.17.11 boots fine with the very same QEMU configuration. Output like the following loops over and over until the dracut emergency shell is spawned. [ 236.862646] ata_piix 0000:00:01.1: dma_direct_map_sg: overflow 0x0000000277583000+4096 of device mask ffffffff [ 236.874151] ata7.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x0 [ 236.876273] ata7.00: failed command: READ DMA [ 236.878413] ata7.00: cmd c8/00:08:00:08:20/00:00:00:00:00/e0 tag 0 dma 4096 in [ 236.878413] res 50/00:00:00:00:00/00:00:00:00:00/b0 Emask 0x40 (internal error) [ 236.890747] ata7.00: status: { DRDY } [ 236.893063] ata7.00: configured for MWDMA2 [ 236.895120] ata7.01: configured for MWDMA2 [ 236.898289] sd 6:0:0:0: [sda] tag#0 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE [ 236.903840] sd 6:0:0:0: [sda] tag#0 Sense Key : Illegal Request [current] [ 236.908104] sd 6:0:0:0: [sda] tag#0 Add. Sense: Unaligned write command [ 236.912203] sd 6:0:0:0: [sda] tag#0 CDB: Read(10) 28 00 00 20 08 00 00 00 08 00 [ 236.916444] print_req_error: I/O error, dev sda, sector 2099200 [ 236.918649] ata7: EH complete I don't know if I've filed this under the correct system: it occurs specifically with QEMU's IDE hard disk device, but it may well be an issue with DMA rather than IDE, or something else. At the moment, I can't provide a full dmesg, as I'm unable to save dmesg output when the VM gets stuck like this, and the serial console in virt-manager doesn't have a large enough scrollback buffer to capture everything before a lot of text has flown by. I haven't tested with x86_64, it may well be an issue there. (I just happened to have been testing i386 to validate 32-bit PTI mitigations that are under development, so I've filed it against that arch.) I can follow up with further information as need be next week. -- You are receiving this mail because: You are watching the assignee of the bug.-- 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
