On Sat, Apr 12, 2025 at 12:43 PM Richard Henderson <richard.hender...@linaro.org> wrote: > > With acce728cbc6c we disallowed configuring 64-bit guests on > 32-bit hosts, but forgot to document that in removed-features. > > Signed-off-by: Richard Henderson <richard.hender...@linaro.org> > --- > docs/about/removed-features.rst | 9 +++++++++ > 1 file changed, 9 insertions(+)
Merged for 10.0 via Michael Tokarev's trivial patches pull request. Stefan > > diff --git a/docs/about/removed-features.rst b/docs/about/removed-features.rst > index 2527a91795..790a5e481c 100644 > --- a/docs/about/removed-features.rst > +++ b/docs/about/removed-features.rst > @@ -858,6 +858,15 @@ QEMU. Since all recent x86 hardware from the past >10 > years is > capable of the 64-bit x86 extensions, a corresponding 64-bit OS should > be used instead. > > +32-bit hosts for 64-bit guests (removed in 10.0) > +'''''''''''''''''''''''''''''''''''''''''''''''' > + > +In general, 32-bit hosts cannot support the memory space or atomicity > +requirements of 64-bit guests. Prior to 10.0, QEMU attempted to > +work around the atomicity issues in system mode by running all vCPUs > +in a single thread context; in user mode atomicity was simply broken. > +From 10.0, QEMU has disabled configuration of 64-bit guests on 32-bit hosts. > + > Guest Emulator ISAs > ------------------- > > -- > 2.43.0 >
