| Message ID | 20240326131410.93866-1-philmd@linaro.org |
|---|---|
| State | New |
| Headers | show |
| Series | [PATCH-for-9.1] hw/i386: Add a config to only build the microvm machine | expand |
26.03.2024 16:14, Philippe Mathieu-Daudé wrote: > Add a config file to build a binary only containing the > microvm machine, inspired by a discussion on the list: > https://lore.kernel.org/qemu-devel/604bf457-23a7-4d06-b59f-a7b46945c626@tls.msk.ru/ > > As suggested in commit d1d5e9eefd ("configure: allow the > selection of alternate config in the build"), it can be > built using: > > $ ../configure --without-default-features \ > --target-list=x86_64-softmmu \ > --with-devices-x86_64=microvm > > Inspired-by: Michael Tokarev <mjt@tls.msk.ru> > Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org> > --- > configs/devices/x86_64-softmmu/microvm.mak | 20 ++++++++++++++++++++ > 1 file changed, 20 insertions(+) > create mode 100644 configs/devices/x86_64-softmmu/microvm.mak This is not enough. This step is good already, but it lacks default machine type selection. In debian we carry a tiny patch to make microvm the default machine type or else it crashes at startup not finding "pc" machine or one of its required devices. /mjt > diff --git a/configs/devices/x86_64-softmmu/microvm.mak b/configs/devices/x86_64-softmmu/microvm.mak > new file mode 100644 > index 0000000000..fe48b5b4a7 > --- /dev/null > +++ b/configs/devices/x86_64-softmmu/microvm.mak > @@ -0,0 +1,20 @@ > +# SPDX-FileCopyrightText: 2024 Linaro Ltd. > +# > +# Config that only supports the 64-bit microvm machine. > +# This avoids bringing in any of numerous legacy features from > +# the legacy machines or the 32bit platform. > +# > + > +CONFIG_MICROVM=y > +CONFIG_PCI_DEVICES=n > +CONFIG_SMBIOS=y > +CONFIG_SMBIOS_LEGACY=n > +CONFIG_VIRTIO_BALLOON=y > +CONFIG_VIRTIO_BLK=y > +CONFIG_VIRTIO_CRYPTO=y > +CONFIG_VIRTIO_GPU=y > +CONFIG_VIRTIO_INPUT=y > +CONFIG_VIRTIO_NET=y > +CONFIG_VIRTIO_RNG=y > +CONFIG_VIRTIO_SCSI=y > +CONFIG_VIRTIO_SERIAL=y
On 26/3/24 16:48, Michael Tokarev wrote: > 26.03.2024 16:14, Philippe Mathieu-Daudé wrote: >> Add a config file to build a binary only containing the >> microvm machine, inspired by a discussion on the list: >> https://lore.kernel.org/qemu-devel/604bf457-23a7-4d06-b59f-a7b46945c626@tls.msk.ru/ >> >> As suggested in commit d1d5e9eefd ("configure: allow the >> selection of alternate config in the build"), it can be >> built using: >> >> $ ../configure --without-default-features \ >> --target-list=x86_64-softmmu \ >> --with-devices-x86_64=microvm >> >> Inspired-by: Michael Tokarev <mjt@tls.msk.ru> >> Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org> >> --- >> configs/devices/x86_64-softmmu/microvm.mak | 20 ++++++++++++++++++++ >> 1 file changed, 20 insertions(+) >> create mode 100644 configs/devices/x86_64-softmmu/microvm.mak > > This is not enough. This step is good already, but it lacks default > machine > type selection. In debian we carry a tiny patch to make microvm the > default > machine type or else it crashes at startup not finding "pc" machine or one > of its required devices. No crash here, what is your base commit? ./qemu-system-x86_64 qemu-system-x86_64: No machine specified, and there is no default Use -machine help to list supported machines $ ./qemu-system-x86_64 -M help Supported machines are: microvm microvm (i386) none empty machine $ > > /mjt
26.03.2024 18:58, Philippe Mathieu-Daudé: >> This is not enough. This step is good already, but it lacks default machine >> type selection. In debian we carry a tiny patch to make microvm the default >> machine type or else it crashes at startup not finding "pc" machine or one >> of its required devices. > > No crash here, what is your base commit? > > ./qemu-system-x86_64 > qemu-system-x86_64: No machine specified, and there is no default > Use -machine help to list supported machines Well, this is definitely better than a crash. I haven't looked at that for a long time, initially it just crashed. Still, this current behavior isn't nice, - in my opinion it should select microvm by default in this case. https://salsa.debian.org/qemu-team/qemu/-/blob/master/debian/patches/microvm-default-machine-type.patch is the outline (from more than 4 years ago), - it's a hack but shows what I mean. /mjt
On Tue, 26 Mar 2024 at 16:03, Michael Tokarev <mjt@tls.msk.ru> wrote: > > 26.03.2024 18:58, Philippe Mathieu-Daudé: > > >> This is not enough. This step is good already, but it lacks default machine > >> type selection. In debian we carry a tiny patch to make microvm the default > >> machine type or else it crashes at startup not finding "pc" machine or one > >> of its required devices. > > > > No crash here, what is your base commit? > > > > ./qemu-system-x86_64 > > qemu-system-x86_64: No machine specified, and there is no default > > Use -machine help to list supported machines > > Well, this is definitely better than a crash. I haven't looked at that for > a long time, initially it just crashed. > > Still, this current behavior isn't nice, - in my opinion it should select > microvm by default in this case. I disagree. We shouldn't present users with a situation where qemu-system-x86_64 binary A has a default of "pc" and qemu-system-x86_64 binary B has a default of "microvm", just because of the way they happened to be compiled. That seems liable to lead to confusion. (In general I think that default machine types are not a great piece of UI which we mostly have for historical reasons and because all x86 machines look very similar.) -- PMM
On Tue, 26 Mar 2024 19:01:50 +0300 Michael Tokarev <mjt@tls.msk.ru> wrote: > 26.03.2024 18:58, Philippe Mathieu-Daudé: > > >> This is not enough. This step is good already, but it lacks default machine > >> type selection. In debian we carry a tiny patch to make microvm the default > >> machine type or else it crashes at startup not finding "pc" machine or one > >> of its required devices. > > > > No crash here, what is your base commit? > > > > ./qemu-system-x86_64 > > qemu-system-x86_64: No machine specified, and there is no default > > Use -machine help to list supported machines > > Well, this is definitely better than a crash. I haven't looked at that for > a long time, initially it just crashed. > > Still, this current behavior isn't nice, - in my opinion it should select > microvm by default in this case. In arm we also don't have default => consensus was to let user pick poison explicitly. Would've don the same for x86 modulo that would break user's scripts expecting default machine. If it's something new like microvm, I wouldn't set default machine that way there won't expectations and won't be a discussion in future when new shiny not-microvm is around and one want's to ship both (like we had with pc vs q35). > https://salsa.debian.org/qemu-team/qemu/-/blob/master/debian/patches/microvm-default-machine-type.patch > is the outline (from more than 4 years ago), - it's a hack but shows what > I mean. > > /mjt >
diff --git a/configs/devices/x86_64-softmmu/microvm.mak b/configs/devices/x86_64-softmmu/microvm.mak new file mode 100644 index 0000000000..fe48b5b4a7 --- /dev/null +++ b/configs/devices/x86_64-softmmu/microvm.mak @@ -0,0 +1,20 @@ +# SPDX-FileCopyrightText: 2024 Linaro Ltd. +# +# Config that only supports the 64-bit microvm machine. +# This avoids bringing in any of numerous legacy features from +# the legacy machines or the 32bit platform. +# + +CONFIG_MICROVM=y +CONFIG_PCI_DEVICES=n +CONFIG_SMBIOS=y +CONFIG_SMBIOS_LEGACY=n +CONFIG_VIRTIO_BALLOON=y +CONFIG_VIRTIO_BLK=y +CONFIG_VIRTIO_CRYPTO=y +CONFIG_VIRTIO_GPU=y +CONFIG_VIRTIO_INPUT=y +CONFIG_VIRTIO_NET=y +CONFIG_VIRTIO_RNG=y +CONFIG_VIRTIO_SCSI=y +CONFIG_VIRTIO_SERIAL=y
Add a config file to build a binary only containing the microvm machine, inspired by a discussion on the list: https://lore.kernel.org/qemu-devel/604bf457-23a7-4d06-b59f-a7b46945c626@tls.msk.ru/ As suggested in commit d1d5e9eefd ("configure: allow the selection of alternate config in the build"), it can be built using: $ ../configure --without-default-features \ --target-list=x86_64-softmmu \ --with-devices-x86_64=microvm Inspired-by: Michael Tokarev <mjt@tls.msk.ru> Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org> --- configs/devices/x86_64-softmmu/microvm.mak | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) create mode 100644 configs/devices/x86_64-softmmu/microvm.mak