For system mode, we can rarely support the amount of RAM that
the guest requires. TCG emulation is restricted to round-robin
mode, which solves many of the atomicity issues, but not those
associated with virtio. In any case, round-robin does nothing
to help the speed of emulation.
For user mode, most emulation does not succeed at all. Most
of the time we cannot even load 64-bit non-PIE binaries due
to lack of a 64-bit address space. Threads are run in
parallel, not round-robin, which means that atomicity
is not handled.
Reviewed-by: Thomas Huth <th...@redhat.com>
Signed-off-by: Richard Henderson <richard.hender...@linaro.org>
---
meson.build | 13 ++++++++++---
1 file changed, 10 insertions(+), 3 deletions(-)
diff --git a/meson.build b/meson.build
index 85317cd63f..ec51827f40 100644
--- a/meson.build
+++ b/meson.build
@@ -3185,6 +3185,9 @@ if host_os == 'windows'
endif
endif
+# Detect host pointer size for the target configuration loop.
+host_long_bits = cc.sizeof('void *') * 8
+
########################
# Target configuration #
########################
@@ -3277,8 +3280,14 @@ foreach target : target_dirs
}
endif
+ config_target += keyval.load('configs/targets' / target + '.mak')
+
target_kconfig = []
foreach sym: accelerators
+ # Disallow 64-bit on 32-bit emulation and virtualization
+ if host_long_bits < config_target['TARGET_LONG_BITS'].to_int()
+ continue
+ endif
if sym == 'CONFIG_TCG' or target in accelerator_targets.get(sym, [])
config_target += { sym: 'y' }
config_all_accel += { sym: 'y' }
@@ -3292,9 +3301,6 @@ foreach target : target_dirs
error('No accelerator available for target @0@'.format(target))
endif
- config_target += keyval.load('configs/targets' / target + '.mak')
- config_target += { 'TARGET_' + config_target['TARGET_ARCH'].to_upper(): 'y' }
-
if 'TARGET_NEED_FDT' in config_target and not fdt.found()
if default_targets
warning('Disabling ' + target + ' due to missing libfdt')
@@ -3307,6 +3313,7 @@ foreach target : target_dirs
actual_target_dirs += target
# Add default keys
+ config_target += { 'TARGET_' + config_target['TARGET_ARCH'].to_upper(): 'y' }
if 'TARGET_BASE_ARCH' not in config_target
config_target += {'TARGET_BASE_ARCH': config_target['TARGET_ARCH']}
endif
--
2.43.0
