From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jan Kiszka <jan.kiszka@web.de>
Subject: Mysterious address matching in assigned_dev_pci_read_config
Date: Sat, 27 Nov 2010 18:02:26 +0100
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Hi,

can anyone explain this code in assigned_dev_pci_read_config?

    ...
    /* vga specific, remove later */
    if (address =3D=3D 0xFC)
        goto do_log;

    fd =3D pci_dev->real_device.config_fd;

again:
    ret =3D pread(fd, &val, len, address);
    if (ret !=3D len) {
        ...
    }

do_log:
    ...

So this skips any read access to address 0xfc and returns 0 for some
"vga specific" reasons. But even if it's supposed to work around issues
with passing through some VGA adapters, this skipping affects all device
types, no?

Unfortunately, this hunk was already part of the very first version, no
hints in git.

Jan


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