ci: take CIFuzz's matrix into consideration

Otherwise the jobs will try to cancel each other out.

Follow-up to 3884837610168e6fb69fc2d5709f6c017a30beb9.

.github/workflows/build_test.yml

@@ -15,6 +15,9 @@ on:
 jobs:
   build:
     runs-on: ubuntu-20.04
+    concurrency:
+      group: ${{ github.workflow }}-${{ matrix.env.COMPILER }}-${{ matrix.env.COMPILER_VERSION }}-${{ github.ref }}
+      cancel-in-progress: true
     strategy:
       fail-fast: false
       matrix:

.github/workflows/cifuzz.yml

@@ -17,32 +17,35 @@ on:
     branches:
       - main
 jobs:
- Fuzzing:
-   runs-on: ubuntu-latest
-   if: github.repository == 'systemd/systemd'
-   strategy:
-     fail-fast: false
-     matrix:
-       sanitizer: [address, undefined, memory]
-   steps:
-   - name: Build Fuzzers (${{ matrix.sanitizer }})
-     id: build
-     uses: google/oss-fuzz/infra/cifuzz/actions/build_fuzzers@master
-     with:
-       oss-fuzz-project-name: 'systemd'
-       dry-run: false
-       allowed-broken-targets-percentage: 0
-       sanitizer: ${{ matrix.sanitizer }}
-   - name: Run Fuzzers (${{ matrix.sanitizer }})
-     uses: google/oss-fuzz/infra/cifuzz/actions/run_fuzzers@master
-     with:
-       oss-fuzz-project-name: 'systemd'
-       fuzz-seconds: 600
-       dry-run: false
-       sanitizer: ${{ matrix.sanitizer }}
-   - name: Upload Crash
-     uses: actions/upload-artifact@v1
-     if: failure() && steps.build.outcome == 'success'
-     with:
-       name: ${{ matrix.sanitizer }}-artifacts
-       path: ./out/artifacts
+  Fuzzing:
+    runs-on: ubuntu-latest
+    if: github.repository == 'systemd/systemd'
+    concurrency:
+      group: ${{ github.workflow }}-${{ matrix.sanitizer }}-${{ github.ref }}
+      cancel-in-progress: true
+    strategy:
+      fail-fast: false
+      matrix:
+        sanitizer: [address, undefined, memory]
+    steps:
+      - name: Build Fuzzers (${{ matrix.sanitizer }})
+        id: build
+        uses: google/oss-fuzz/infra/cifuzz/actions/build_fuzzers@master
+        with:
+          oss-fuzz-project-name: 'systemd'
+          dry-run: false
+          allowed-broken-targets-percentage: 0
+          sanitizer: ${{ matrix.sanitizer }}
+      - name: Run Fuzzers (${{ matrix.sanitizer }})
+        uses: google/oss-fuzz/infra/cifuzz/actions/run_fuzzers@master
+        with:
+          oss-fuzz-project-name: 'systemd'
+          fuzz-seconds: 600
+          dry-run: false
+          sanitizer: ${{ matrix.sanitizer }}
+      - name: Upload Crash
+        uses: actions/upload-artifact@v1
+        if: failure() && steps.build.outcome == 'success'
+        with:
+          name: ${{ matrix.sanitizer }}-artifacts
+          path: ./out/artifacts

.github/workflows/linter.yml

@@ -13,6 +13,9 @@ jobs:
   build:
     name: Lint Code Base
     runs-on: ubuntu-latest
+    concurrency:
+      group: ${{ github.workflow }}-${{ github.ref }}
+      cancel-in-progress: true
 
     steps:
       - name: Repo checkout

.github/workflows/mkosi.yml

@@ -15,6 +15,9 @@ on:
 jobs:
   ci:
     runs-on: ubuntu-20.04
+    concurrency:
+      group: ${{ github.workflow }}-${{ matrix.distro }}-${{ github.ref }}
+      cancel-in-progress: true
     strategy:
       fail-fast: false
       matrix:

.github/workflows/unit_tests.yml

@@ -4,10 +4,6 @@
 #
 name: Unit tests
 on:
-  # On push/merge to main we only run the GCC job, to get coverage data uploaded to coveralls.io
-  push:
-    branches:
-      - main
   pull_request:
     branches:
       - main
@@ -15,6 +11,9 @@ on:
 jobs:
   build:
     runs-on: ubuntu-20.04
+    concurrency:
+      group: ${{ github.workflow }}-${{ matrix.run_phase }}-${{ github.ref }}
+      cancel-in-progress: true
     strategy:
       fail-fast: false
       matrix:
@@ -22,10 +21,7 @@ jobs:
     steps:
       - name: Repository checkout
         uses: actions/checkout@v2
-        if: github.event_name == 'pull_request' || matrix.run_phase == 'GCC'
       - name: Install build dependencies
         run: sudo -E .github/workflows/unit_tests.sh SETUP
-        if: github.event_name == 'pull_request' || matrix.run_phase == 'GCC'
       - name: Build & test (${{ matrix.run_phase }})
         run: sudo -E .github/workflows/unit_tests.sh RUN_${{ matrix.run_phase }}
-        if: github.event_name == 'pull_request' || matrix.run_phase == 'GCC'

docs/DISCOVERABLE_PARTITIONS.md

@@ -306,11 +306,9 @@ installation processes of Linux a bit more robust and self-descriptive.
 
 ### Why did you only define the root partition for these listed architectures?
 
-The automatic discovery of the root partition is defined to operate on the disk
-containing the current EFI System Partition (ESP). Since EFI only exists on
-x86, x86-64, ia64, ARM, LoongArch and RISC-V so far, we only defined root
-partition UUIDs for these architectures.  Should EFI become more common on
-other architectures, we can define additional UUIDs for them.
+Please submit a patch that adds appropriate partition type UUIDs for the
+architecture of your choice should they be missing so far. The only reason they
+aren't defined yet is that nobody submitted them yet.
 
 ### Why define distinct root partition UUIDs for the various architectures?
 

docs/PORTING_TO_NEW_ARCHITECTURES.md

@@ -0,0 +1,61 @@
+---
+title: Porting to New Architectures
+category: Contributing
+layout: default
+SPDX-License-Identifier: LGPL-2.1-or-later
+---
+
+# Porting systemd to New Architectures
+
+Here's a brief checklist of things to implement when porting systemd to a new
+architecture.
+
+1. Patch
+   [src/basic/architecture.h](https://github.com/systemd/systemd/blob/main/src/basic/architecture.h)
+   and
+   [src/basic/architecture.c](https://github.com/systemd/systemd/blob/main/src/basic/architecture.c)
+   to make your architecture known to systemd. Besides an `ARCHITECTURE_XYZ`
+   enumeration entry you need to provide an implementation of
+   `native_architecture()` and `uname_architecture()`.
+
+2. Patch
+   [src/shared/gpt.h](https://github.com/systemd/systemd/blob/main/src/shared/gpt.h)
+   and
+   [src/shared/gpt.c](https://github.com/systemd/systemd/blob/main/src/shared/gpt.c)
+   and define a new set of GPT partition type UUIDs for the root file system,
+   `/usr/` file system, and the matching Verity and Verity signature
+   partitions. Use `systemd-id128 new -p` to generate new suitable UUIDs you
+   can use for this. Make sure to register your new types in the various
+   functions in `gpt.c`. Also make sure to update the tables in
+   `docs/DISCOVERABLE_PARTITIONS.md` and `man/systemd-gpt-auto-generator.xml`
+   accordingly.
+
+3. If your architecture supports UEFI, make sure to update the `efi_arch`
+   variable logic in `meson.build` to be set to the right architecture string
+   as defined by the UEFI specification. (This ensures that `systemd-boot` will
+   be built as the appropriately named `BOOT<arch>.EFI` binary.) Also, if your
+   architecture uses a special boot protocol for the Linux kernel make sure to
+   implement it in `src/boot/efi/linux*.c`, so that the `systemd-stub` EFI stub
+   can work.
+
+4. Make sure to register the right system call numbers for your architecture in
+   `src/basic/missing_syscall_def.h`. systemd uses various system calls the
+   Linux kernel provides that are currently not wrapped by glibc (or are only
+   in very new glibc), and we need to know the right numbers for them. It might
+   also be necessary to tweak `src/basic/raw-clone.h`.
+
+5. Make sure the code in `src/shared/seccomp-util.c` properly understands the
+   local architecture and its system call quirks.
+
+6. If your architecture uses a `/lib64/` library directory, then make sure that
+   the `BaseFilesystem` table in `src/shared/base-filesystem.c` has an entry
+   for it so that it can be set up automatically if missing. This is useful to
+   support booting into OS trees that have an empty root directory with only
+   `/usr/` mounted in.
+
+7. If your architecture has a CPU opcode similar to x86' RDRAND consider adding
+   native support for it to `src/basic/random-util.c`'s `rdrand()` function.
+
+8. If your architecture supports VM virtualization and provides CPU opcodes
+   similar to x86' CPUID consider adding native support for detecting VMs this
+   way to `src/basic/virt.c`.

meson.build

@@ -1641,39 +1641,8 @@ conf.set10('SYSTEMD_SLOW_TESTS_DEFAULT', slow_tests)
 
 #####################################################################
 
-if get_option('efi')
-        efi_arch = host_machine.cpu_family()
-
-        if efi_arch == 'x86'
-                EFI_MACHINE_TYPE_NAME = 'ia32'
-                gnu_efi_arch = 'ia32'
-        elif efi_arch == 'x86_64'
-                EFI_MACHINE_TYPE_NAME = 'x64'
-                gnu_efi_arch = 'x86_64'
-        elif efi_arch == 'arm'
-                EFI_MACHINE_TYPE_NAME = 'arm'
-                gnu_efi_arch = 'arm'
-        elif efi_arch == 'aarch64'
-                EFI_MACHINE_TYPE_NAME = 'aa64'
-                gnu_efi_arch = 'aarch64'
-        elif efi_arch == 'riscv64'
-                EFI_MACHINE_TYPE_NAME = 'riscv64'
-                gnu_efi_arch = 'riscv64'
-        else
-                EFI_MACHINE_TYPE_NAME = ''
-                gnu_efi_arch = ''
-        endif
-
-        have = true
-        conf.set_quoted('EFI_MACHINE_TYPE_NAME', EFI_MACHINE_TYPE_NAME)
-else
-        have = false
-endif
-conf.set10('ENABLE_EFI', have)
-
 subdir('src/fundamental')
 subdir('src/boot/efi')
-conf.set10('HAVE_GNU_EFI', have_gnu_efi)
 
 ############################################################
 
@@ -3887,19 +3856,14 @@ summary({
 # CPPFLAGS: ${OUR_CPPFLAGS} ${CPPFLAGS}
 # LDFLAGS:  ${OUR_LDFLAGS} ${LDFLAGS}
 
-if conf.get('ENABLE_EFI') == 1
-        summary({'EFI arch' : efi_arch},
+if conf.get('ENABLE_EFI') == 1 and conf.get('HAVE_GNU_EFI') == 1
+        summary({
+                'EFI machine type' :                efi_arch[0],
+                'EFI CC' :                          '@0@'.format(' '.join(efi_cc)),
+                'EFI lds' :                         efi_lds,
+                'EFI crt0' :                        efi_crt0,
+                'EFI include directory' :           efi_incdir},
                 section : 'Extensible Firmware Interface')
-
-        if have_gnu_efi
-                summary({
-                        'EFI machine type' :                EFI_MACHINE_TYPE_NAME,
-                        'EFI CC' :                          '@0@'.format(' '.join(efi_cc)),
-                        'EFI lds' :                         efi_lds,
-                        'EFI crt0' :                        efi_crt0,
-                        'EFI include directory' :           efi_incdir},
-                        section : 'Extensible Firmware Interface')
-        endif
 endif
 
 found = []
@@ -3947,11 +3911,11 @@ foreach tuple : [
         # components
         ['backlight'],
         ['binfmt'],
-        ['bpf-framework',         conf.get('BPF_FRAMEWORK') == 1],
+        ['bpf-framework'],
         ['coredump'],
         ['environment.d'],
         ['efi'],
-        ['gnu-efi',               have_gnu_efi],
+        ['gnu-efi'],
         ['firstboot'],
         ['hibernate'],
         ['homed'],
@@ -4008,7 +3972,7 @@ foreach tuple : [
         ['debug hashmap'],
         ['debug mmap cache'],
         ['debug siphash'],
-        ['valgrind',              conf.get('VALGRIND') == 1],
+        ['valgrind'],
         ['trace logging',         conf.get('LOG_TRACE') == 1],
         ['install tests',         install_tests],
         ['link-udev-shared',      get_option('link-udev-shared')],

src/basic/architecture.c

@@ -106,8 +106,7 @@ int uname_architecture(void) {
                 { "crisv32",    ARCHITECTURE_CRIS     },
 #elif defined(__nios2__)
                 { "nios2",      ARCHITECTURE_NIOS2    },
-#elif defined(__riscv__) || defined(__riscv)
-        /* __riscv__ is obsolete, remove in 2018 */
+#elif defined(__riscv)
                 { "riscv32",    ARCHITECTURE_RISCV32  },
                 { "riscv64",    ARCHITECTURE_RISCV64  },
 #  if __SIZEOF_POINTER__ == 4

src/basic/architecture.h

@@ -210,8 +210,7 @@ int uname_architecture(void);
 #elif defined(__nios2__)
 #  define native_architecture() ARCHITECTURE_NIOS2
 #  define LIB_ARCH_TUPLE "nios2-linux-gnu"
-#elif defined(__riscv__) || defined(__riscv)
-        /* __riscv__ is obsolete, remove in 2018 */
+#elif defined(__riscv)
 #  if __SIZEOF_POINTER__ == 4
 #    define native_architecture() ARCHITECTURE_RISCV32
 #    define LIB_ARCH_TUPLE "riscv32-linux-gnu"

src/boot/efi/meson.build

@@ -1,5 +1,102 @@
 # SPDX-License-Identifier: LGPL-2.1-or-later
 
+conf.set10('ENABLE_EFI', get_option('efi'))
+conf.set10('HAVE_GNU_EFI', false)
+
+if not get_option('efi') or get_option('gnu-efi') == 'false'
+        if get_option('gnu-efi') == 'true'
+                error('gnu-efi support requested, but general efi support is disabled')
+        endif
+        subdir_done()
+endif
+
+efi_arch = {
+        # host_cc_arch: [efi_arch (see Table 3-2 in UEFI spec), gnu_efi_inc_arch]
+        'x86':     ['ia32', 'ia32'],
+        'x86_64':  ['x64', 'x86_64'],
+        'arm':     ['arm', 'arm'],
+        'aarch64': ['aa64', 'aarch64'],
+        'riscv64': ['riscv64', 'riscv64'],
+}.get(host_machine.cpu_family(), [])
+
+efi_incdir = get_option('efi-includedir')
+if efi_arch.length() > 0 and not cc.has_header('@0@/@1@/efibind.h'.format(efi_incdir, efi_arch[1]))
+        efi_arch = []
+endif
+
+if efi_arch.length() == 0
+        if get_option('gnu-efi') == 'true'
+                error('gnu-efi support requested, but headers not found or efi arch is unkown')
+        endif
+        warning('gnu-efi headers not found or efi arch is unkown, disabling gnu-efi support')
+        subdir_done()
+endif
+
+if not cc.has_header_symbol('efi.h', 'EFI_IMAGE_MACHINE_X64',
+                include_directories: include_directories(efi_incdir, efi_incdir / efi_arch[1]))
+
+        if get_option('gnu-efi') == 'true'
+                error('gnu-efi support requested, but found headers are too old (3.0.5+ required)')
+        endif
+        warning('gnu-efi headers are too old (3.0.5+ required), disabling gnu-efi support')
+        subdir_done()
+endif
+
+objcopy = find_program('objcopy')
+efi_cc = get_option('efi-cc')
+if efi_cc.length() == 0
+        efi_cc = cc.cmd_array()
+endif
+
+efi_ld = find_program(get_option('efi-ld'))
+efi_ld_name = efi_ld.path().split('/')[-1]
+if efi_ld_name == 'lld' or efi_ld_name == 'ld.lld'
+        # LLVM/LLD does not support PE/COFF relocations
+        # https://lists.llvm.org/pipermail/llvm-dev/2021-March/149234.html
+        error('LLVM/lld does not support PE/COFF relocations. Use different linker for EFI image.')
+endif
+
+efi_libdir = ''
+foreach dir : [get_option('efi-libdir'),
+               '/usr/lib/gnuefi' / efi_arch[0],
+               run_command('realpath', '-e',
+                        '/usr/lib' / run_command(efi_cc, '-print-multi-os-directory').stdout().strip()).stdout().strip()]
+        if run_command(test, '-d', dir).returncode() == 0
+                efi_libdir = dir
+                break
+        endif
+endforeach
+if efi_libdir == ''
+        if get_option('gnu-efi') == 'true'
+                error('gnu-efi support requested, but efi-libdir was not found')
+        endif
+        warning('efi-libdir was not found, disabling gnu-efi support')
+        subdir_done()
+endif
+
+efi_lds = ''
+foreach location : [ # New locations first introduced with gnu-efi 3.0.11
+                    [efi_libdir / 'efi.lds',
+                     efi_libdir / 'crt0.o'],
+                    # Older locations...
+                    [efi_libdir / 'gnuefi' / 'elf_@0@_efi.lds'.format(efi_arch[1]),
+                     efi_libdir / 'gnuefi' / 'crt0-efi-@0@.o'.format(efi_arch[1])],
+                    [efi_libdir / 'elf_@0@_efi.lds'.format(efi_arch[1]),
+                     efi_libdir / 'crt0-efi-@0@.o'.format(efi_arch[1])]]
+        if run_command(test, '-f', location[0], '-a', '-f', location[1]).returncode() == 0
+                efi_lds = location[0]
+                efi_crt0 = location[1]
+                break
+        endif
+endforeach
+if efi_lds == ''
+        if get_option('gnu-efi') == 'true'
+                error('gnu-efi support requested, but cannot find efi.lds')
+        endif
+        warning('efi.lds was not found, disabling gnu-efi support')
+        subdir_done()
+endif
+
 efi_headers = files('''
         console.h
         cpio.h
@@ -39,312 +136,206 @@ systemd_boot_sources = '''
 '''.split()
 
 stub_sources = '''
+        cpio.c
         initrd.c
         splash.c
         stub.c
-        cpio.c
 '''.split()
 
-if efi_arch in ['x86', 'x86_64']
+if efi_arch[1] in ['ia32', 'x86_64']
         stub_sources += 'linux_x86.c'
 else
         stub_sources += 'linux.c'
 endif
 
-if conf.get('ENABLE_EFI') == 1 and get_option('gnu-efi') != 'false'
-        efi_cc = get_option('efi-cc')
-        if efi_cc.length() == 0
-                efi_cc = cc.cmd_array()
+conf.set10('HAVE_GNU_EFI', true)
+conf.set_quoted('EFI_MACHINE_TYPE_NAME', efi_arch[0])
+
+efi_conf = configuration_data()
+efi_conf.set_quoted('EFI_MACHINE_TYPE_NAME', efi_arch[0])
+efi_conf.set10('ENABLE_TPM', get_option('tpm'))
+
+foreach ctype : ['color-normal', 'color-entry', 'color-highlight', 'color-edit']
+        c = get_option('efi-' + ctype).split(',')
+        efi_conf.set(ctype.underscorify().to_upper(), 'EFI_TEXT_ATTR(@0@, @1@)'.format(
+                'EFI_' + c[0].strip().underscorify().to_upper(),
+                'EFI_' + c[1].strip().underscorify().to_upper()))
+endforeach
+
+if get_option('sbat-distro') != ''
+        efi_conf.set_quoted('SBAT_PROJECT', meson.project_name())
+        efi_conf.set_quoted('PROJECT_VERSION', meson.project_version())
+        efi_conf.set('PROJECT_URL', conf.get('PROJECT_URL'))
+        if get_option('sbat-distro-generation') < 1
+                error('SBAT Distro Generation must be a positive integer')
         endif
-
-        efi_ld = find_program(get_option('efi-ld'), required: true)
-        efi_ld_name = efi_ld.path().split('/')[-1]
-        if efi_ld_name == 'lld' or efi_ld_name == 'ld.lld'
-                # LLVM/LLD does not support PE/COFF relocations
-                # https://lists.llvm.org/pipermail/llvm-dev/2021-March/149234.html
-                error('LLVM/lld does not support PE/COFF relocations. Use different linker for EFI image.')
-        endif
-
-        efi_incdir = get_option('efi-includedir')
-
-        gnu_efi_path_arch = ''
-        foreach name : [gnu_efi_arch, EFI_MACHINE_TYPE_NAME]
-                if (gnu_efi_path_arch == '' and name != '' and
-                    cc.has_header('@0@/@1@/efibind.h'.format(efi_incdir, name)))
-                        gnu_efi_path_arch = name
+        efi_conf.set('SBAT_DISTRO_GENERATION', get_option('sbat-distro-generation'))
+        foreach sbatvar : [['sbat-distro', 'ID'],
+                           ['sbat-distro-summary', 'NAME'],
+                           ['sbat-distro-url', 'BUG_REPORT_URL']]
+                value = get_option(sbatvar[0])
+                if (value == '' and not meson.is_cross_build()) or value == 'auto'
+                        cmd = 'if [ -e /etc/os-release ]; then . /etc/os-release; else . /usr/lib/os-release; fi; echo $@0@'.format(sbatvar[1])
+                        value = run_command(sh, '-c', cmd).stdout().strip()
+                        message('@0@ (from @1@): @2@'.format(sbatvar[0], sbatvar[1], value))
                 endif
+                if value == ''
+                        error('Required @0@ option not set and autodetection failed'.format(sbatvar[0]))
+                endif
+                efi_conf.set_quoted(sbatvar[0].underscorify().to_upper(), value)
         endforeach
 
-        if gnu_efi_path_arch != '' and EFI_MACHINE_TYPE_NAME == ''
-                error('gnu-efi is available, but EFI_MACHINE_TYPE_NAME is unknown')
+        pkgname = get_option('sbat-distro-pkgname')
+        if pkgname == ''
+                pkgname = meson.project_name()
         endif
+        efi_conf.set_quoted('SBAT_DISTRO_PKGNAME', pkgname)
 
-        efi_libdir = get_option('efi-libdir')
-        if efi_libdir == ''
-                # New location first introduced with gnu-efi 3.0.11
-                efi_libdir = '/usr/lib/gnuefi' / EFI_MACHINE_TYPE_NAME
-                cmd = run_command(test, '-e', efi_libdir)
-
-                if cmd.returncode() != 0
-                        # Fall back to the old approach
-                        cmd = run_command(efi_cc + ['-print-multi-os-directory'])
-                        if cmd.returncode() == 0
-                                path = '/usr/lib' / cmd.stdout().strip()
-                                cmd = run_command(env, 'realpath', '-e', path)
-                                if cmd.returncode() == 0
-                                        efi_libdir = cmd.stdout().strip()
-                                endif
-                        endif
-                endif
-        endif
-
-        have_gnu_efi = gnu_efi_path_arch != '' and efi_libdir != ''
-
-        if have_gnu_efi and not cc.has_header_symbol('efi.h', 'EFI_IMAGE_MACHINE_X64',
-           include_directories: include_directories(efi_incdir, efi_incdir / gnu_efi_path_arch))
-                have_gnu_efi = false
-                if get_option('gnu-efi') == 'true'
-                        error('gnu-efi support requested, but found headers are too old (3.0.5+ required)')
-                endif
-        endif
-else
-        have_gnu_efi = false
-endif
-
-if get_option('gnu-efi') == 'true' and not have_gnu_efi
-        error('gnu-efi support requested, but headers were not found')
-endif
-
-if have_gnu_efi
-        efi_conf = configuration_data()
-        efi_conf.set_quoted('EFI_MACHINE_TYPE_NAME', EFI_MACHINE_TYPE_NAME)
-        efi_conf.set10('ENABLE_TPM', get_option('tpm'))
-
-        foreach ctype : ['color-normal', 'color-entry', 'color-highlight', 'color-edit']
-                c = get_option('efi-' + ctype).split(',')
-                fg = 'EFI_' + c[0].strip().underscorify().to_upper()
-                bg = 'EFI_BACKGROUND_' + c[1].strip().underscorify().to_upper()
-                efi_conf.set(ctype.underscorify().to_upper(), '(' + fg + '|' + bg + ')')
-        endforeach
-
-        if get_option('sbat-distro') != ''
-                efi_conf.set_quoted('SBAT_PROJECT', meson.project_name())
-                efi_conf.set_quoted('PROJECT_VERSION', meson.project_version())
-                efi_conf.set('PROJECT_URL', conf.get('PROJECT_URL'))
-                if get_option('sbat-distro-generation') < 1
-                       error('SBAT Distro Generation must be a positive integer')
-                endif
-                efi_conf.set('SBAT_DISTRO_GENERATION', get_option('sbat-distro-generation'))
-                sbatvars = [['sbat-distro', 'ID'],
-                            ['sbat-distro-summary', 'NAME'],
-                            ['sbat-distro-url', 'BUG_REPORT_URL']]
-                foreach sbatvar : sbatvars
-                        value = get_option(sbatvar[0])
-                        if (value == '' and not meson.is_cross_build()) or value == 'auto'
-                                cmd = 'if [ -e /etc/os-release ]; then . /etc/os-release; else . /usr/lib/os-release; fi; echo $@0@'.format(sbatvar[1])
-                                value = run_command(sh, '-c', cmd).stdout().strip()
-                                message('@0@ (from @1@): @2@'.format(sbatvar[0], sbatvar[1], value))
-                        endif
-                        if value == ''
-                                error('Required @0@ option not set and autodetection failed'.format(sbatvar[0]))
-                        endif
-                        efi_conf.set_quoted(sbatvar[0].underscorify().to_upper(), value)
-                endforeach
-
-                pkgname = get_option('sbat-distro-pkgname')
-                if pkgname == ''
-                        pkgname = meson.project_name()
-                endif
-                efi_conf.set_quoted('SBAT_DISTRO_PKGNAME', pkgname)
-
-                pkgver = get_option('sbat-distro-version')
-                if pkgver == ''
-                        efi_conf.set('SBAT_DISTRO_VERSION', 'GIT_VERSION')
-                else
-                        efi_conf.set_quoted('SBAT_DISTRO_VERSION', pkgver)
-                endif
-        endif
-
-        efi_config_h = configure_file(
-                output : 'efi_config.h',
-                configuration : efi_conf)
-
-        objcopy = find_program('objcopy')
-
-        efi_location_map = [
-                # New locations first introduced with gnu-efi 3.0.11
-                [efi_libdir / 'efi.lds',
-                 efi_libdir / 'crt0.o'],
-                # Older locations...
-                [efi_libdir / 'gnuefi' / 'elf_@0@_efi.lds'.format(gnu_efi_path_arch),
-                 efi_libdir / 'gnuefi' / 'crt0-efi-@0@.o'.format(gnu_efi_path_arch)],
-                [efi_libdir / 'elf_@0@_efi.lds'.format(gnu_efi_path_arch),
-                 efi_libdir / 'crt0-efi-@0@.o'.format(gnu_efi_path_arch)]]
-        efi_lds = ''
-        foreach location : efi_location_map
-                if efi_lds == ''
-                        cmd = run_command(test, '-f', location[0])
-                        if cmd.returncode() == 0
-                                efi_lds = location[0]
-                                efi_crt0 = location[1]
-                        endif
-                endif
-        endforeach
-        if efi_lds == ''
-                if get_option('gnu-efi') == 'true'
-                        error('gnu-efi support requested, but cannot find efi.lds')
-                else
-                        have_gnu_efi = false
-                endif
-        endif
-endif
-
-if have_gnu_efi
-        compile_args = cc.get_supported_arguments(
-                basic_disabled_warnings +
-                possible_common_cc_flags + [
-                        '-fno-stack-protector',
-                        '-fno-strict-aliasing',
-                        '-fpic',
-                        '-fwide-exec-charset=UCS2',
-                        '-Wall',
-                        '-Wextra',
-                        '-Wsign-compare',
-                ]
-        ) + [
-                '-nostdlib',
-                '-std=gnu99',
-                '-ffreestanding',
-                '-fshort-wchar',
-                '-isystem', efi_incdir,
-                '-isystem', efi_incdir / gnu_efi_path_arch,
-                '-I', fundamental_path,
-                '-DSD_BOOT',
-                '-DGNU_EFI_USE_MS_ABI',
-                '-include', efi_config_h,
-                '-include', version_h,
-        ]
-
-        if efi_arch == 'x86_64'
-                compile_args += ['-mno-red-zone',
-                                 '-mno-sse',
-                                 '-mno-mmx']
-        elif efi_arch == 'x86'
-                compile_args += ['-mno-sse',
-                                 '-mno-mmx']
-        elif efi_arch == 'arm'
-                compile_args += cc.get_supported_arguments([
-                        '-mgeneral-regs-only',
-                        '-mfpu=none'
-                ])
-        endif
-
-        # We are putting the efi_cc command line together ourselves, so make sure to pull any
-        # relevant compiler flags from meson/CFLAGS as povided by the user or distro.
-
-        if get_option('werror')
-                compile_args += ['-Werror']
-        endif
-        if get_option('debug')
-                compile_args += ['-ggdb', '-DEFI_DEBUG']
-        endif
-        if get_option('optimization') != '0'
-                compile_args += ['-O' + get_option('optimization')]
-        endif
-        if get_option('b_ndebug') == 'true' or (
-           get_option('b_ndebug') == 'if-release' and ['plain', 'release'].contains(get_option('buildtype')))
-                compile_args += ['-DNDEBUG']
-        endif
-
-        foreach arg : get_option('c_args')
-                if arg in ['-Werror', '-g', '-ggdb', '-O1', '-O2', '-O3', '-Og', '-Os', '-DNDEBUG']
-                        message('Using "@0@" from c_args for EFI compiler'.format(arg))
-                        compile_args += arg
-                endif
-        endforeach
-
-        efi_ldflags = ['-T', efi_lds,
-                       '-shared',
-                       '-Bsymbolic',
-                       '-nostdlib',
-                       '--no-undefined',
-                       '--warn-common',
-                       '--fatal-warnings',
-                       '-znocombreloc',
-                       '--build-id=sha1',
-                       '-L', efi_libdir,
-                       efi_crt0]
-        if ['aarch64', 'arm', 'riscv64'].contains(efi_arch)
-                # Aarch64, ARM32 and 64bit RISC-V don't have an EFI capable objcopy.
-                # Use 'binary' instead, and add required symbols manually.
-                efi_ldflags += ['--defsym=EFI_SUBSYSTEM=0xa']
-                efi_format = ['-O', 'binary']
+        pkgver = get_option('sbat-distro-version')
+        if pkgver == ''
+                efi_conf.set('SBAT_DISTRO_VERSION', 'GIT_VERSION')
         else
-                efi_format = ['--target=efi-app-@0@'.format(gnu_efi_arch)]
+                efi_conf.set_quoted('SBAT_DISTRO_VERSION', pkgver)
         endif
-
-        systemd_boot_objects = []
-        stub_objects = []
-        foreach file : fundamental_source_paths + common_sources + systemd_boot_sources + stub_sources
-                o_file = custom_target(file.split('/')[-1] + '.o',
-                                       input : file,
-                                       output : file.split('/')[-1] + '.o',
-                                       command : efi_cc + ['-c', '@INPUT@', '-o', '@OUTPUT@']
-                                                 + compile_args,
-                                       depend_files : efi_headers + fundamental_headers)
-                if (fundamental_source_paths + common_sources + systemd_boot_sources).contains(file)
-                        systemd_boot_objects += o_file
-                endif
-                if (fundamental_source_paths + common_sources + stub_sources).contains(file)
-                        stub_objects += o_file
-                endif
-        endforeach
-
-        libgcc_file_name = run_command(efi_cc + ['-print-libgcc-file-name']).stdout().strip()
-        systemd_boot_efi_name = 'systemd-boot@0@.efi'.format(EFI_MACHINE_TYPE_NAME)
-        stub_elf_name = 'linux@0@.elf.stub'.format(EFI_MACHINE_TYPE_NAME)
-        stub_efi_name = 'linux@0@.efi.stub'.format(EFI_MACHINE_TYPE_NAME)
-
-        efi_stubs = []
-        foreach tuple : [['systemd_boot.so', systemd_boot_efi_name, systemd_boot_objects, false],
-                         [stub_elf_name, stub_efi_name, stub_objects, true]]
-                so = custom_target(
-                        tuple[0],
-                        input : tuple[2],
-                        output : tuple[0],
-                        command : [efi_ld, '-o', '@OUTPUT@',
-                                   efi_ldflags, tuple[2],
-                                   '-lefi', '-lgnuefi', libgcc_file_name],
-                        install : tuple[3],
-                        install_dir : bootlibdir)
-
-                stub = custom_target(
-                        tuple[1],
-                        input : so,
-                        output : tuple[1],
-                        command : [objcopy,
-                                   '-j', '.data',
-                                   '-j', '.dynamic',
-                                   '-j', '.dynsym',
-                                   '-j', '.osrel',
-                                   '-j', '.rel*',
-                                   '-j', '.sbat',
-                                   '-j', '.sdata',
-                                   '-j', '.sdmagic',
-                                   '-j', '.text',
-                                   efi_format,
-                                   '@INPUT@', '@OUTPUT@'],
-                        install : true,
-                        install_dir : bootlibdir)
-
-                efi_stubs += [[so, stub]]
-        endforeach
-
-        ############################################################
-
-        test_efi_disk_img = custom_target(
-                'test-efi-disk.img',
-                input : [efi_stubs[0][0], efi_stubs[1][1]],
-                output : 'test-efi-disk.img',
-                command : [test_efi_create_disk_sh, '@OUTPUT@','@INPUT@', splash_bmp])
 endif
+
+efi_config_h = configure_file(
+        output : 'efi_config.h',
+        configuration : efi_conf)
+
+compile_args = cc.get_supported_arguments(
+        basic_disabled_warnings +
+        possible_common_cc_flags + [
+                '-fno-stack-protector',
+                '-fno-strict-aliasing',
+                '-fpic',
+                '-fwide-exec-charset=UCS2',
+                '-Wall',
+                '-Wextra',
+                '-Wsign-compare',
+        ]
+) + [
+        '-nostdlib',
+        '-std=gnu99',
+        '-ffreestanding',
+        '-fshort-wchar',
+        '-isystem', efi_incdir,
+        '-isystem', efi_incdir / efi_arch[1],
+        '-I', fundamental_path,
+        '-DSD_BOOT',
+        '-DGNU_EFI_USE_MS_ABI',
+        '-include', efi_config_h,
+        '-include', version_h,
+]
+
+compile_args += cc.get_supported_arguments({
+        'ia32':   ['-mno-sse', '-mno-mmx'],
+        'x86_64': ['-mno-red-zone', '-mno-sse', '-mno-mmx'],
+        'arm':    ['-mgeneral-regs-only', '-mfpu=none'],
+}.get(efi_arch[1], []))
+
+# We are putting the efi_cc command line together ourselves, so make sure to pull any
+# relevant compiler flags from meson/CFLAGS as povided by the user or distro.
+
+if get_option('werror')
+        compile_args += ['-Werror']
+endif
+if get_option('debug')
+        compile_args += ['-ggdb', '-DEFI_DEBUG']
+endif
+if get_option('optimization') != '0'
+        compile_args += ['-O' + get_option('optimization')]
+endif
+if get_option('b_ndebug') == 'true' or (
+   get_option('b_ndebug') == 'if-release' and get_option('buildtype') in ['plain', 'release'])
+        compile_args += ['-DNDEBUG']
+endif
+
+foreach arg : get_option('c_args')
+        if arg in ['-Werror', '-g', '-ggdb', '-O1', '-O2', '-O3', '-Og', '-Os', '-DNDEBUG']
+                message('Using "@0@" from c_args for EFI compiler'.format(arg))
+                compile_args += arg
+        endif
+endforeach
+
+efi_ldflags = ['-T', efi_lds,
+               '-shared',
+               '-Bsymbolic',
+               '-nostdlib',
+               '--no-undefined',
+               '--warn-common',
+               '--fatal-warnings',
+               '-znocombreloc',
+               '--build-id=sha1',
+               '-L', efi_libdir,
+               efi_crt0]
+if efi_arch[1] in ['aarch64', 'arm', 'riscv64']
+        # Aarch64, ARM32 and 64bit RISC-V don't have an EFI capable objcopy.
+        # Use 'binary' instead, and add required symbols manually.
+        efi_ldflags += ['--defsym=EFI_SUBSYSTEM=0xa']
+        efi_format = ['-O', 'binary']
+else
+        efi_format = ['--target=efi-app-@0@'.format(efi_arch[1])]
+endif
+
+systemd_boot_objects = []
+stub_objects = []
+foreach file : fundamental_source_paths + common_sources + systemd_boot_sources + stub_sources
+        o_file = custom_target(file.split('/')[-1] + '.o',
+                               input : file,
+                               output : file.split('/')[-1] + '.o',
+                               command : [efi_cc, '-c', '@INPUT@', '-o', '@OUTPUT@', compile_args],
+                               depend_files : efi_headers + fundamental_headers)
+        if (fundamental_source_paths + common_sources + systemd_boot_sources).contains(file)
+                systemd_boot_objects += o_file
+        endif
+        if (fundamental_source_paths + common_sources + stub_sources).contains(file)
+                stub_objects += o_file
+        endif
+endforeach
+
+libgcc_file_name = run_command(efi_cc + ['-print-libgcc-file-name']).stdout().strip()
+systemd_boot_efi_name = 'systemd-boot@0@.efi'.format(efi_arch[0])
+stub_elf_name = 'linux@0@.elf.stub'.format(efi_arch[0])
+stub_efi_name = 'linux@0@.efi.stub'.format(efi_arch[0])
+
+efi_stubs = []
+foreach tuple : [['systemd_boot.so', systemd_boot_efi_name, systemd_boot_objects, false],
+                 [stub_elf_name, stub_efi_name, stub_objects, true]]
+        so = custom_target(
+                tuple[0],
+                input : tuple[2],
+                output : tuple[0],
+                command : [efi_ld, '-o', '@OUTPUT@', efi_ldflags, tuple[2], '-lefi', '-lgnuefi', libgcc_file_name],
+                install : tuple[3],
+                install_dir : bootlibdir)
+
+        stub = custom_target(
+                tuple[1],
+                input : so,
+                output : tuple[1],
+                command : [objcopy,
+                           '-j', '.data',
+                           '-j', '.dynamic',
+                           '-j', '.dynsym',
+                           '-j', '.osrel',
+                           '-j', '.rel*',
+                           '-j', '.sbat',
+                           '-j', '.sdata',
+                           '-j', '.sdmagic',
+                           '-j', '.text',
+                           efi_format,
+                           '@INPUT@', '@OUTPUT@'],
+                install : true,
+                install_dir : bootlibdir)
+
+        efi_stubs += [[so, stub]]
+endforeach
+
+############################################################
+
+test_efi_disk_img = custom_target(
+        'test-efi-disk.img',
+        input : [efi_stubs[0][0], efi_stubs[1][1]],
+        output : 'test-efi-disk.img',
+        command : [test_efi_create_disk_sh, '@OUTPUT@','@INPUT@', splash_bmp])

src/shared/base-filesystem.c

@@ -20,10 +20,10 @@
 #include "user-util.h"
 
 typedef struct BaseFilesystem {
-        const char *dir;
+        const char *dir;      /* directory or symlink to create */
         mode_t mode;
-        const char *target;
-        const char *exists;
+        const char *target;   /* if non-NULL create as symlink to this target */
+        const char *exists;   /* conditionalize this entry on existance of this file */
         bool ignore_failure;
 } BaseFilesystem;
 
@@ -39,11 +39,26 @@ static const BaseFilesystem table[] = {
         { "sys",   0755, NULL,                         NULL, true },
         { "dev",   0755, NULL,                         NULL, true },
 #if defined(__i386__) || defined(__x86_64__)
+        /* Various architecture ABIs define the path to the dynamic loader via the /lib64/ subdirectory of
+         * the root directory. When booting from an otherwise empty root file system (where only /usr/ has
+         * been mounted into) it is thus necessary to create a symlink pointing to the right subdirectory of
+         * /usr/ first — otherwise we couldn't invoke any dynamic binary. Let's detect this case here, and
+         * create the symlink as needed should it be missing. We prefer doing this consistently with Debian's
+         * multiarch logic, but support Fedora-style multilib too.*/
         { "lib64",    0, "usr/lib/x86_64-linux-gnu\0"
                          "usr/lib64\0",                "ld-linux-x86-64.so.2" },
+#else
+        /* gcc doesn't allow pragma to be used within constructs, hence log about this separately below */
+#  define WARN_LIB64 1
 #endif
 };
 
+#ifdef WARN_LIB64
+#pragma message "If your architecture knows a /lib64/ or /lib32/ directory, please add an entry creating it here."
+        /* And if your architecture doesn't know these directories, make sure to add ifdeffery here to
+         * suppress this pragma message. */
+#endif
+
 int base_filesystem_create(const char *root, uid_t uid, gid_t gid) {
         _cleanup_close_ int fd = -1;
         int r;

src/shared/gpt.c

@@ -4,6 +4,16 @@
 #include "string-util.h"
 #include "utf8.h"
 
+/* Gently push people towards defining GPT type UUIDs for all architectures we know */
+#if !defined(GPT_ROOT_NATIVE) ||                                        \
+        !defined(GPT_ROOT_NATIVE_VERITY) ||                             \
+        !defined(GPT_ROOT_NATIVE_VERITY_SIG) ||                         \
+        !defined(GPT_USR_NATIVE) ||                                     \
+        !defined(GPT_USR_NATIVE_VERITY) ||                              \
+        !defined(GPT_USR_NATIVE_VERITY_SIG)
+#pragma message "Please define GPT partition types for your architecture."
+#endif
+
 const GptPartitionType gpt_partition_type_table[] = {
         { GPT_ROOT_X86,                    "root-x86"                    },
         { GPT_ROOT_X86_VERITY,             "root-x86-verity"             },