From acce728cbc6c154b215dfc8d05c12d8fcc2483d5 Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Sun, 2 Feb 2025 15:09:23 -0800 Subject: [PATCH] meson: Disallow 64-bit on 32-bit emulation MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit 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 Reviewed-by: Philippe Mathieu-Daudé Signed-off-by: Richard Henderson --- 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 -- 2.39.5