On Mon, Mar 15, 2021 at 05:58:04PM +0100, Reinoud Zandijk wrote: > Hi, > > with the introduction of the following patch from 17th of February, Win10 > won't boot anymore without explicitly setting the machine to be 5.2 compatible > like pc-1440fx-5.2. The default 6.0 will cause it to panic and gives as reason > only "ACPI error".
Thanks for the report! Could you provide a bit more detail please? Which windows version is used, which qemu command line, etc etc. Also does this only affect pre-installed guests? what if you install a fresh copy of windows? > It might work to counter a bug in Linux but this is not the place to do the > patch. The BSDs don't care and will boot fine with full ACPI regardless of the > machine chosen. Windows 10 however DOES care and gets confused. > > I think its better to revert this and fix Linux ;) or make it a selectable > feature as a workaround that's by default OFF :) > > With regards, > Reinoud > > > The patch concerned is: > > commit 6be8cf56bc8bda2ed9a070bdb04446191f31acc9 > Author: Isaku Yamahata <isaku.yamah...@intel.com> > Date: Wed Feb 17 21:51:12 2021 -0800 > > acpi/core: always set SCI_EN when SMM isn't supported > > If SMM is not supported, ACPI fixed hardware doesn't support > legacy-mode. ACPI-only platform. Where SCI_EN in PM1_CNT register is > always set. > The bit tells OS legacy mode(SCI_EN cleared) or ACPI mode(SCI_EN set). > > With the next patch (setting fadt.smi_cmd = 0 when smm isn't enabled), > guest Linux tries to switch to ACPI mode, finds smi_cmd = 0, and then > fails to initialize acpi subsystem. This patch proactively fixes it. > > This patch changes guest ABI. To keep compatibility, use > "smm-compat" introduced by earlier patch. If the property is true, > disable new behavior. > > ACPI spec 4.8.10.1 PM1 Event Grouping > PM1 Eanble Registers > > For ACPI-only platforms (where SCI_EN is always set) > > Reviewed-by: Igor Mammedov <imamm...@redhat.com> > Signed-off-by: Isaku Yamahata <isaku.yamah...@intel.com> > Message-Id: > <500f62081626997e46f96377393d3662211763a8.1613615732.git.isaku.yamah...@intel.com> > Reviewed-by: Michael S. Tsirkin <m...@redhat.com> > Signed-off-by: Michael S. Tsirkin <m...@redhat.com> > > hw/acpi/core.c | 11 ++++++++++- > hw/acpi/ich9.c | 2 +- > hw/acpi/piix4.c | 3 ++- > hw/core/machine.c | 5 ++++- > hw/isa/vt82c686.c | 2 +- > include/hw/acpi/acpi.h | 4 +++- > 6 files changed, 21 insertions(+), 6 deletions(-) > >
