| Message ID | 20201116183114.55703-1-hare@suse.de (mailing list archive) |
|---|---|
| Headers | show |
| Series | scsi: infinite guest hangs with scsi-disk | expand |
Patchew URL: https://patchew.org/QEMU/20201116183114.55703-1-hare@suse.de/ Hi, This series seems to have some coding style problems. See output below for more information: Message-id: 20201116183114.55703-1-hare@suse.de Type: series Subject: [PATCH 0/3] scsi: infinite guest hangs with scsi-disk === TEST SCRIPT BEGIN === #!/bin/bash git rev-parse base > /dev/null || exit 0 git config --local diff.renamelimit 0 git config --local diff.renames True git config --local diff.algorithm histogram ./scripts/checkpatch.pl --mailback base.. === TEST SCRIPT END === Updating 3c8cf5a9c21ff8782164d1def7f44bd888713384 From https://github.com/patchew-project/qemu - [tag update] patchew/20201116104617.18333-1-peter.maydell@linaro.org -> patchew/20201116104617.18333-1-peter.maydell@linaro.org - [tag update] patchew/20201116165506.31315-1-eperezma@redhat.com -> patchew/20201116165506.31315-1-eperezma@redhat.com * [new tag] patchew/20201116183114.55703-1-hare@suse.de -> patchew/20201116183114.55703-1-hare@suse.de Switched to a new branch 'test' 350bcf1 scsi: add tracing for SG_IO commands 7ecf5b6 scsi: make io_timeout configurable 450c008 virtio-scsi: trace events === OUTPUT BEGIN === 1/3 Checking commit 450c008843e5 (virtio-scsi: trace events) ERROR: trailing whitespace #116: FILE: hw/scsi/virtio-scsi.c:797: + $ total: 1 errors, 0 warnings, 92 lines checked Patch 1/3 has style problems, please review. If any of these errors are false positives report them to the maintainer, see CHECKPATCH in MAINTAINERS. 2/3 Checking commit 7ecf5b611a5b (scsi: make io_timeout configurable) 3/3 Checking commit 350bcf121178 (scsi: add tracing for SG_IO commands) === OUTPUT END === Test command exited with code: 1 The full log is available at http://patchew.org/logs/20201116183114.55703-1-hare@suse.de/testing.checkpatch/?type=message. --- Email generated automatically by Patchew [https://patchew.org/]. Please send your feedback to patchew-devel@redhat.com
On 16/11/20 19:31, Hannes Reinecke wrote: > Hi all, > > one of our customers reported an infinite guest hang following an FC link loss when using scsi-disk. > Problem is that scsi-disk issues SG_IO command with a timeout of UINT_MAX, which essentially signals > 'no timeout' to the host kernel. So if the command gets lost eg during an unexpected link loss the > HBA driver will never attempt to abort or return the command. Hence the guest will hang forever, and > the only way to resolve things is to reboot the host. > > To solve it this patchset adds an 'io_timeout' parameter to scsi-disk and scsi-generic, which allows > the admin to specify a command timeout for SG_IO request. It is initialized to 30 seconds to avoid the > infinite hang as mentioned above. > > As usual, comments and reviews are welcome. > > Hannes Reinecke (3): > virtio-scsi: trace events > scsi: make io_timeout configurable > scsi: add tracing for SG_IO commands > > hw/scsi/scsi-disk.c | 9 ++++++--- > hw/scsi/scsi-generic.c | 25 ++++++++++++++++++------- > hw/scsi/trace-events | 13 +++++++++++++ > hw/scsi/virtio-scsi.c | 30 +++++++++++++++++++++++++++++- > include/hw/scsi/scsi.h | 4 +++- > 5 files changed, 69 insertions(+), 12 deletions(-) > The UINT_MAX timeout predates me, but I think the idea was to make it sort of like NFS's hard option. Without a timeout you cannot be quite sure if/when the command will stay in some buffer of the HBA or the SAN or the target, and there could be unintended reordering of writes. Though I guess at some point you'll anyway restart the VM on another host and the same reordering can happen, so I've queued the patch. Paolo