Comment 4 for bug 1886362

Another reproducer: (just to record)

cat << EOF | ./i386-softmmu/qemu-system-i386 -M pc-q35-5.0 \
-netdev user,id=qtest-bn0 -device e1000e,netdev=qtest-bn0 \
-display none -nodefaults -nographic -qtest stdio
outl 0xcf8 0x80000810
outl 0xcfc 0xe0000000
outl 0xcf8 0x80000804
outw 0xcfc 0x7
write 0xe0000758 0x4 0xfffff1ff
write 0xe0000760 0x6 0xffffdf000000
write 0xe0000768 0x4 0x0efffff1
write 0xe0005008 0x4 0x18ffff27
write 0xe0000c 0x1 0x66
write 0xe03320 0x1 0xff
write 0xe03620 0x1 0xff
write 0xe00000f3 0x1 0xdf
write 0xe0000100 0x6 0xdfffffdf0000
write 0xe0000110 0x5 0xdfffffdf00
write 0xe000011a 0x3 0xffffff
write 0xe0000128 0x5 0x7e00ffffff
write 0xe0000403 0x1 0xdf
write 0xe0000420 0x4 0xdfffffdf
write 0xe000042a 0x3 0xffffff
write 0xe0000438 0x1 0x7e
EOF

-> https://lists.gnu.org/archive/html/qemu-devel/2020-07/msg05709.html