Hi, On Fri, Aug 29, 2025 at 07:37:09PM +0900, Akihiko Odaki wrote: > On 2025/08/28 17:17, Arun Menon wrote: > > H Akihiko, > > > > Thanks for the review. > > > > On Thu, Aug 28, 2025 at 10:34:54AM +0900, Akihiko Odaki wrote: > > > On 2025/08/21 17:43, Arun Menon wrote: > > > > This is an incremental step in converting vmstate loading > > > > code to report error via Error objects instead of directly > > > > printing it to console/monitor. > > > > It is ensured that vmstate_load_state() must report an error > > > > in errp, in case of failure. > > > > > > > > The errors are temporarily reported using warn_report_err(). > > > > This is removed in the subsequent patches in this series, > > > > when we are actually able to propagate the error to the calling > > > > function using errp. Whereas, if we want the function to exit on > > > > error, then error_fatal is passed. > > > > > > > > Reviewed-by: Marc-André Lureau <[email protected]> > > > > Signed-off-by: Arun Menon <[email protected]> > > > > --- > > > > hw/display/virtio-gpu.c | 2 +- > > > > hw/pci/pci.c | 3 ++- > > > > hw/s390x/virtio-ccw.c | 2 +- > > > > hw/scsi/spapr_vscsi.c | 4 ++- > > > > hw/vfio/pci.c | 5 +++- > > > > hw/virtio/virtio-mmio.c | 3 ++- > > > > hw/virtio/virtio-pci.c | 2 +- > > > > hw/virtio/virtio.c | 7 +++-- > > > > include/migration/vmstate.h | 2 +- > > > > migration/cpr.c | 3 +-- > > > > migration/savevm.c | 8 ++++-- > > > > migration/vmstate-types.c | 22 +++++++++++---- > > > > migration/vmstate.c | 65 > > > > +++++++++++++++++++++++++++++++-------------- > > > > tests/unit/test-vmstate.c | 63 > > > > ++++++++++++++++++++++++++++++++++++------- > > > > ui/vdagent.c | 5 +++- > > > > 15 files changed, 147 insertions(+), 49 deletions(-) > > > > > > > > diff --git a/hw/display/virtio-gpu.c b/hw/display/virtio-gpu.c > > > > index > > > > 0a1a625b0ea6cf26cb0d799171a57ed3d3ab2442..5dc31bc6bfb0272e29a4364ab10de2595a4bedf7 > > > > 100644 > > > > --- a/hw/display/virtio-gpu.c > > > > +++ b/hw/display/virtio-gpu.c > > > > @@ -1343,7 +1343,7 @@ static int virtio_gpu_load(QEMUFile *f, void > > > > *opaque, size_t size, > > > > } > > > > /* load & apply scanout state */ > > > > - vmstate_load_state(f, &vmstate_virtio_gpu_scanouts, g, 1); > > > > + vmstate_load_state(f, &vmstate_virtio_gpu_scanouts, g, 1, > > > > &error_fatal); > > > > return 0; > > > > } > > > > diff --git a/hw/pci/pci.c b/hw/pci/pci.c > > > > index > > > > c70b5ceebaf1f2b10768bd030526cbb518da2b8d..6be932d3bb67ff0c4808707db2a7b6378a90e82b > > > > 100644 > > > > --- a/hw/pci/pci.c > > > > +++ b/hw/pci/pci.c > > > > @@ -934,7 +934,8 @@ void pci_device_save(PCIDevice *s, QEMUFile *f) > > > > int pci_device_load(PCIDevice *s, QEMUFile *f) > > > > { > > > > int ret; > > > > - ret = vmstate_load_state(f, &vmstate_pci_device, s, s->version_id); > > > > + ret = vmstate_load_state(f, &vmstate_pci_device, s, s->version_id, > > > > + &error_fatal); > > > > /* Restore the interrupt status bit. */ > > > > pci_update_irq_status(s); > > > > return ret; > > > > diff --git a/hw/s390x/virtio-ccw.c b/hw/s390x/virtio-ccw.c > > > > index > > > > d2f85b39f30f7fc82e0c600144c0a958e1269b2c..6a9641a03d5d3a38a4de7ceb9deffc0cc303bcff > > > > 100644 > > > > --- a/hw/s390x/virtio-ccw.c > > > > +++ b/hw/s390x/virtio-ccw.c > > > > @@ -1136,7 +1136,7 @@ static void virtio_ccw_save_config(DeviceState > > > > *d, QEMUFile *f) > > > > static int virtio_ccw_load_config(DeviceState *d, QEMUFile *f) > > > > { > > > > VirtioCcwDevice *dev = VIRTIO_CCW_DEVICE(d); > > > > - return vmstate_load_state(f, &vmstate_virtio_ccw_dev, dev, 1); > > > > + return vmstate_load_state(f, &vmstate_virtio_ccw_dev, dev, 1, > > > > &error_fatal); > > > > } > > > > static void virtio_ccw_pre_plugged(DeviceState *d, Error **errp) > > > > diff --git a/hw/scsi/spapr_vscsi.c b/hw/scsi/spapr_vscsi.c > > > > index > > > > 20f70fb2729de78b9636a6b8c869695dab4f8902..8622419497db650523d51bcb41557bbca254eaa3 > > > > 100644 > > > > --- a/hw/scsi/spapr_vscsi.c > > > > +++ b/hw/scsi/spapr_vscsi.c > > > > @@ -642,15 +642,17 @@ static void *vscsi_load_request(QEMUFile *f, > > > > SCSIRequest *sreq) > > > > VSCSIState *s = VIO_SPAPR_VSCSI_DEVICE(bus->qbus.parent); > > > > vscsi_req *req; > > > > int rc; > > > > + Error *local_err = NULL; > > > > assert(sreq->tag < VSCSI_REQ_LIMIT); > > > > req = &s->reqs[sreq->tag]; > > > > assert(!req->active); > > > > memset(req, 0, sizeof(*req)); > > > > - rc = vmstate_load_state(f, &vmstate_spapr_vscsi_req, req, 1); > > > > + rc = vmstate_load_state(f, &vmstate_spapr_vscsi_req, req, 1, > > > > &local_err); > > > > if (rc) { > > > > fprintf(stderr, "VSCSI: failed loading request tag#%u\n", > > > > sreq->tag); > > > > + warn_report_err(local_err); > > > > return NULL; > > > > } > > > > assert(req->active); > > > > diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c > > > > index > > > > 4fa692c1a32bcfa4e4939e5fcb64f2bf19905b3b..a65e34b6979eadfa0851666aeae7cf731a00fa40 > > > > 100644 > > > > --- a/hw/vfio/pci.c > > > > +++ b/hw/vfio/pci.c > > > > @@ -2790,13 +2790,16 @@ static int vfio_pci_load_config(VFIODevice > > > > *vbasedev, QEMUFile *f) > > > > PCIDevice *pdev = &vdev->pdev; > > > > pcibus_t old_addr[PCI_NUM_REGIONS - 1]; > > > > int bar, ret; > > > > + Error *local_err = NULL; > > > > for (bar = 0; bar < PCI_ROM_SLOT; bar++) { > > > > old_addr[bar] = pdev->io_regions[bar].addr; > > > > } > > > > - ret = vmstate_load_state(f, &vmstate_vfio_pci_config, vdev, 1); > > > > + ret = vmstate_load_state(f, &vmstate_vfio_pci_config, vdev, 1, > > > > + &local_err); > > > > if (ret) { > > > > + warn_report_err(local_err); > > > > return ret; > > > > } > > > > diff --git a/hw/virtio/virtio-mmio.c b/hw/virtio/virtio-mmio.c > > > > index > > > > 532c67107ba1d2978a76cf49f9cdc1de1dea3e11..0a688909fc606a3c9fde933667ae8c309ab527d0 > > > > 100644 > > > > --- a/hw/virtio/virtio-mmio.c > > > > +++ b/hw/virtio/virtio-mmio.c > > > > @@ -34,6 +34,7 @@ > > > > #include "qemu/error-report.h" > > > > #include "qemu/log.h" > > > > #include "trace.h" > > > > +#include "qapi/error.h" > > > > static bool virtio_mmio_ioeventfd_enabled(DeviceState *d) > > > > { > > > > @@ -619,7 +620,7 @@ static int virtio_mmio_load_extra_state(DeviceState > > > > *opaque, QEMUFile *f) > > > > { > > > > VirtIOMMIOProxy *proxy = VIRTIO_MMIO(opaque); > > > > - return vmstate_load_state(f, &vmstate_virtio_mmio, proxy, 1); > > > > + return vmstate_load_state(f, &vmstate_virtio_mmio, proxy, 1, > > > > &error_fatal); > > > > } > > > > static bool virtio_mmio_has_extra_state(DeviceState *opaque) > > > > diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c > > > > index > > > > 767216d795998708f5716a23ae16c79cd90ff489..b04faa1e5c91b5cef40e54ec41d92422d16bfc13 > > > > 100644 > > > > --- a/hw/virtio/virtio-pci.c > > > > +++ b/hw/virtio/virtio-pci.c > > > > @@ -161,7 +161,7 @@ static int virtio_pci_load_extra_state(DeviceState > > > > *d, QEMUFile *f) > > > > { > > > > VirtIOPCIProxy *proxy = to_virtio_pci_proxy(d); > > > > - return vmstate_load_state(f, &vmstate_virtio_pci, proxy, 1); > > > > + return vmstate_load_state(f, &vmstate_virtio_pci, proxy, 1, > > > > &error_fatal); > > > > } > > > > static void virtio_pci_save_queue(DeviceState *d, int n, QEMUFile *f) > > > > diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c > > > > index > > > > 9a81ad912e013fc254899c4e55cff1f76a6112a4..419f3516c9f0a3df43831eebc77aa1e6dfcd0f41 > > > > 100644 > > > > --- a/hw/virtio/virtio.c > > > > +++ b/hw/virtio/virtio.c > > > > @@ -3235,6 +3235,7 @@ virtio_load(VirtIODevice *vdev, QEMUFile *f, int > > > > version_id) > > > > BusState *qbus = qdev_get_parent_bus(DEVICE(vdev)); > > > > VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); > > > > VirtioDeviceClass *vdc = VIRTIO_DEVICE_GET_CLASS(vdev); > > > > + Error *local_err = NULL; > > > > /* > > > > * We poison the endianness to ensure it does not get used before > > > > @@ -3327,15 +3328,17 @@ virtio_load(VirtIODevice *vdev, QEMUFile *f, > > > > int version_id) > > > > } > > > > if (vdc->vmsd) { > > > > - ret = vmstate_load_state(f, vdc->vmsd, vdev, version_id); > > > > + ret = vmstate_load_state(f, vdc->vmsd, vdev, version_id, > > > > &local_err); > > > > if (ret) { > > > > + warn_report_err(local_err); > > > > > > I think error_report_err() should be used instead because this is > > > replacing > > > error_report(). > > > > > > If I read correctly, warn_report_err() is essentially error_report_err() > > > prefixing the message with "warning: ". However, the error messages > > > handled > > > in this series do not have such prefixes so you shouldn't add them in > > > intemediate changes. > > > > If I am not wrong, we have introduced warn_report_err() not as a > > replacement to > > error_report(). They are newly added ones. Besides, some of them are not > > intermediate > > changes, because they do end up in the final version. for example in > > hw/virtio/virtio-pci.c > > I referred to the fact that the messages that were emitted with > error_report() calls in vmstate_load_state() are now printed with > warn_report_err(). That causes behavioral changes and I suspect that they > are accidental. > > I especially want to know reasoning behind them if it is not accidental and > some of them are going to remain after applying the entire series. > > > In some places in the intermediate patches a warn_report_err() is added > > right after > > error_report(), both to be replaced with error_setg()/error_prepend() later > > in the series. > > The appropriate choice will depend on how Errors generated by error_setg() > are going to be reported to the user in that case. Using warn_report_err() > for them is inappropriate if they are going to reported with > error_report_err(). If they are going to be handled in some special way, > keeping the original behavior is a sensible option, and I think > error_report_err() does that in most cases, if not all. > > > > > Do you want to replace warn_report_err() everywhere with error_report_err()? > > Perhaps so, but I may have missed some cases where warn_report_err(), so let > me share some sort of guideline I have in my mind: > > - Keeping the original behavior is a safe choice. > > If "warning: " was not prepended in the past, leaving messages without the > prefix is at least not a regression, so reviewers can give Reviewed-by: more > easily. > > - Refer to Markus' email, which provides distinctions among "ordinary" > erros, programming errors, and warnings and I see it reasonable: > https://lore.kernel.org/qemu-devel/[email protected]/ > ("Abuse of warnings for unhandled errors and programming errors") >
Yes most of them are going to be reported with error_report_err() in the end. So keeping the warning prefix does not make sense. I agree. I shall amend and send a new version. Thank you so much. > Regards, > Akihiko Odaki > Regards, Arun Menon
