id = 733
title = "Qemu Adventcalendar 2020 ELKS fails to run with error \"qemu-system-x86_64: at most one isa-vga device is permitted\""
state = "closed"
created_at = "2021-11-17T18:00:06.012Z"
closed_at = "2021-12-06T19:17:32.815Z"
labels = ["CLI", "Regression", "device:graphics", "kind::Bug", "workflow::Confirmed"]
url = "https://gitlab.com/qemu-project/qemu/-/issues/733"
host-os = "Debian Linux"
host-arch = "x86"
qemu-version = "6.1.90 (git bisect determines commit 7852a77f59)"
guest-os = "ELKS"
guest-arch = "Intel IA16 architecture"
description = """Running ELKS from Qemu Advent calendar results in:
qemu-system-x86_64: at most one isa-vga device is permitted"""
reproduce = """(with ELKS)
1. Untar https://download.qemu.org/qemu-6.2.0-rc0.tar.xz
1. Build qemu-system-x86_64
2. Download https://www.qemu-advent-calendar.org/2020/download/day23.tar.gz
3. Execute ELKS as described in run.sh"""
additional = """A git bisect was performed to identify the culprit commit:
```
qemu$ git bisect good
binäre Suche: danach noch 1 Commit zum Testen übrig (ungefähr 1 Schritt)
[2b3a98255c90d8d2f9f87a73eb33371961508517] hw/display/xlnx_dp: fix an out-of-bounds read in xlnx_dp_read

qemu$ ./configure --target-list=x86_64-softmmu --disable-linux-user && make -j2

qemu$ build/qemu-system-x86_64 -machine isapc -vga std
qemu-system-x86_64: at most one isa-vga device is permitted

qemu$ git bisect bad
binäre Suche: danach noch 0 Commits zum Testen übrig (ungefähr 0 Schritte)
[7852a77f598635a67a222b6c1463c8b46098aed2] vga: don't abort when adding a duplicate isa-vga device

qemu$ cat .git/refs/bisect/bad
2b3a98255c90d8d2f9f87a73eb33371961508517

qemu$ git status
HEAD losgelöst bei 7852a77f59

```"""