iOS does not support ucontext natively for aarch64 and the sigaltstack is also unsupported (even worse, it fails silently, see: https://openradar.appspot.com/13002712 )
As a workaround we include a library implementation of ucontext and add it as a build option. Signed-off-by: Joelle van Dyne <j...@getutm.app> --- configure | 21 ++++++++++++++++++--- meson.build | 12 +++++++++++- util/coroutine-ucontext.c | 9 +++++++++ .gitmodules | 3 +++ MAINTAINERS | 6 ++++++ meson_options.txt | 2 ++ subprojects/libucontext | 1 + 7 files changed, 50 insertions(+), 4 deletions(-) create mode 160000 subprojects/libucontext diff --git a/configure b/configure index 34fccaa2ba..5f225894a9 100755 --- a/configure +++ b/configure @@ -1773,7 +1773,7 @@ Advanced options (experts only): --oss-lib path to OSS library --cpu=CPU Build for host CPU [$cpu] --with-coroutine=BACKEND coroutine backend. Supported options: - ucontext, sigaltstack, windows + ucontext, libucontext, sigaltstack, windows --enable-gcov enable test coverage analysis with gcov --disable-blobs disable installing provided firmware blobs --with-vss-sdk=SDK-path enable Windows VSS support in QEMU Guest Agent @@ -4517,12 +4517,27 @@ else error_exit "only the 'windows' coroutine backend is valid for Windows" fi ;; + libucontext) + ;; *) error_exit "unknown coroutine backend $coroutine" ;; esac fi +case $coroutine in +libucontext) + git_submodules="${git_submodules} subprojects/libucontext" + mkdir -p libucontext + coroutine_impl=ucontext + libucontext="enabled" + ;; +*) + coroutine_impl=$coroutine + libucontext="disabled" + ;; +esac + if test "$coroutine_pool" = ""; then coroutine_pool=yes fi @@ -5858,7 +5873,7 @@ if test "$qom_cast_debug" = "yes" ; then echo "CONFIG_QOM_CAST_DEBUG=y" >> $config_host_mak fi -echo "CONFIG_COROUTINE_BACKEND=$coroutine" >> $config_host_mak +echo "CONFIG_COROUTINE_BACKEND=$coroutine_impl" >> $config_host_mak if test "$coroutine_pool" = "yes" ; then echo "CONFIG_COROUTINE_POOL=1" >> $config_host_mak else @@ -6421,7 +6436,7 @@ NINJA=$ninja $meson setup \ -Dlibnfs=$libnfs -Diconv=$iconv -Dcurses=$curses -Dlibudev=$libudev\ -Drbd=$rbd -Dlzo=$lzo -Dsnappy=$snappy -Dlzfse=$lzfse \ -Dzstd=$zstd -Dseccomp=$seccomp -Dvirtfs=$virtfs -Dcap_ng=$cap_ng \ - -Dattr=$attr -Ddefault_devices=$default_devices \ + -Dattr=$attr -Ddefault_devices=$default_devices -Ducontext=$libucontext \ -Ddocs=$docs -Dsphinx_build=$sphinx_build -Dinstall_blobs=$blobs \ -Dvhost_user_blk_server=$vhost_user_blk_server -Dmultiprocess=$multiprocess \ -Dfuse=$fuse -Dfuse_lseek=$fuse_lseek -Dguest_agent_msi=$guest_agent_msi \ diff --git a/meson.build b/meson.build index adeec153d9..2440d90734 100644 --- a/meson.build +++ b/meson.build @@ -1633,9 +1633,18 @@ if not fdt.found() and fdt_required.length() > 0 error('fdt not available but required by targets ' + ', '.join(fdt_required)) endif +ucontext = dependency('libucontext', kwargs: static_kwargs, required : false) +if not ucontext.found() and get_option('ucontext').enabled() + libucontext_proj = subproject('libucontext', + default_options: ['default_library=static', + 'freestanding=true']) + ucontext = libucontext_proj.get_variable('libucontext_dep') +endif + config_host_data.set('CONFIG_CAPSTONE', capstone.found()) config_host_data.set('CONFIG_FDT', fdt.found()) config_host_data.set('CONFIG_SLIRP', slirp.found()) +config_host_data.set('CONFIG_LIBUCONTEXT', ucontext.found()) ##################### # Generated sources # @@ -1883,7 +1892,7 @@ util_ss.add_all(trace_ss) util_ss = util_ss.apply(config_all, strict: false) libqemuutil = static_library('qemuutil', sources: util_ss.sources() + stub_ss.sources() + genh, - dependencies: [util_ss.dependencies(), m, glib, socket, malloc]) + dependencies: [util_ss.dependencies(), m, glib, socket, malloc, ucontext]) qemuutil = declare_dependency(link_with: libqemuutil, sources: genh + version_res) @@ -2579,6 +2588,7 @@ summary(summary_info, bool_yn: true, section: 'Targets and accelerators') # Block layer summary_info = {} +summary_info += {'libucontext support': ucontext.found()} summary_info += {'coroutine backend': config_host['CONFIG_COROUTINE_BACKEND']} summary_info += {'coroutine pool': config_host['CONFIG_COROUTINE_POOL'] == '1'} if have_block diff --git a/util/coroutine-ucontext.c b/util/coroutine-ucontext.c index 904b375192..220c57a743 100644 --- a/util/coroutine-ucontext.c +++ b/util/coroutine-ucontext.c @@ -23,7 +23,16 @@ #undef _FORTIFY_SOURCE #endif #include "qemu/osdep.h" +#if defined(CONFIG_LIBUCONTEXT) +#include <libucontext/libucontext.h> +#define ucontext_t libucontext_ucontext_t +#define getcontext libucontext_getcontext +#define setcontext libucontext_setcontext +#define swapcontext libucontext_swapcontext +#define makecontext libucontext_makecontext +#else #include <ucontext.h> +#endif #include "qemu/coroutine_int.h" #ifdef CONFIG_VALGRIND_H diff --git a/.gitmodules b/.gitmodules index 08b1b48a09..6434b98c49 100644 --- a/.gitmodules +++ b/.gitmodules @@ -64,3 +64,6 @@ [submodule "roms/vbootrom"] path = roms/vbootrom url = https://gitlab.com/qemu-project/vbootrom.git +[submodule "libucontext"] + path = subprojects/libucontext + url = https://github.com/kaniini/libucontext.git diff --git a/MAINTAINERS b/MAINTAINERS index f22d83c178..76de0c7dcb 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -2893,6 +2893,12 @@ F: hw/core/clock-vmstate.c F: hw/core/qdev-clock.c F: docs/devel/clocks.rst +libucontext in QEMU +M: Joelle van Dyne <j...@getutm.app> +S: Maintained +F: subprojects/libucontext +K: ^Subject:.*(?i)libucontext + Usermode Emulation ------------------ Overall usermode emulation diff --git a/meson_options.txt b/meson_options.txt index 9734019995..5db4ef21f8 100644 --- a/meson_options.txt +++ b/meson_options.txt @@ -108,6 +108,8 @@ option('fuse', type: 'feature', value: 'auto', description: 'FUSE block device export') option('fuse_lseek', type : 'feature', value : 'auto', description: 'SEEK_HOLE/SEEK_DATA support for FUSE exports') +option('ucontext', type : 'feature', value : 'disabled', + description: 'libucontext support') option('vhost_user_blk_server', type: 'feature', value: 'auto', description: 'build vhost-user-blk server') diff --git a/subprojects/libucontext b/subprojects/libucontext new file mode 160000 index 0000000000..464f98a01b --- /dev/null +++ b/subprojects/libucontext @@ -0,0 +1 @@ +Subproject commit 464f98a01b41006f9dc68ff0eee0aa2656709acc -- 2.28.0