vmstate_load_state return error into virtio_load function

[Jingtao]

Qemu version 4.2.1

In the function of virtio_load, the vmstate_load_state will return error in the following case.

The virtio is legacy mode(disable-modern=on,disable-legacy=off), virtio_device is in reset state.

In the the function of "vmstate_load_state", it will load all subsection. For the vmstate_virtio_extra_state subsection.
It will execute:
vmstate_load_state -->
          ret = field->info->get(f, curr_elem, size, field); line 143 vmstate.c.
           -->virtio_pci_load_extra_state
                        --> vmstate_load_state
                                 -->qemu_peek_byte
But if the f->buf_index is same with buf_size, qemu_peek_byte function will set "-EIO" error.
the field->info->get will return 0, then it will get the error "ret = qemu_file_get_error(f);". then the vmstate_load_state will return error.

It output is "Failed to load virtio/extra_state:extra_state"

[Thomas Huth (th-huth)]

Can you also reproduce this with the latest version of QEMU? Anyway:
The QEMU project is currently moving its bug tracking to another system.
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closed already. Thus we are setting the bug state to "Incomplete" now.

If the bug has already been fixed in the latest upstream version of QEMU,
then please close this ticket as "Fix released".

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[Launchpad Janitor (janitor)]

[Expired for QEMU because there has been no activity for 60 days.]