From: Luca Boccassi <bluca@debian.org>
Date: Mon, 12 Dec 2022 23:59:00 +0000 (+0000)
Subject: idmap: also check for kernel version
X-Git-Tag: v15~382
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=7739be13fef78b4ec8bcaafc58d4f35e294990fe;p=thirdparty%2Fmkosi.git

idmap: also check for kernel version

Not only nspawn 252 is required, but also kernel 5.12 for id-mapped mounts
to be available
---

diff --git a/mkosi/__init__.py b/mkosi/__init__.py
index dbb791792..859dc1b01 100644
--- a/mkosi/__init__.py
+++ b/mkosi/__init__.py
@@ -1759,6 +1759,20 @@ def configure_serial_terminal(state: MkosiState, cached: bool) -> None:
                           """)
 
 
+def nspawn_id_map_supported() -> bool:
+    if nspawn_version() < 252:
+        return False
+
+    try:
+        # Not part of stdlib
+        from packaging import version
+    except ImportError:
+        # If we can't check assume the kernel is new enough
+        return True
+
+    return version.parse(platform.release()) >= version.LegacyVersion("5.12")
+
+
 def nspawn_params_for_build_sources(config: MkosiConfig, sft: SourceFileTransfer) -> List[str]:
     params = []
 
@@ -1766,7 +1780,7 @@ def nspawn_params_for_build_sources(config: MkosiConfig, sft: SourceFileTransfer
         params += ["--setenv=SRCDIR=/root/src",
                    "--chdir=/root/src"]
         if sft == SourceFileTransfer.mount:
-            idmap_opt = ":rootidmap" if nspawn_version() >= 252 else ""
+            idmap_opt = ":rootidmap" if nspawn_id_map_supported() else ""
             params += [f"--bind={config.build_sources}:/root/src{idmap_opt}"]
 
         if config.read_only:
@@ -5976,7 +5990,7 @@ def run_build_script(state: MkosiState, raw: Optional[BinaryIO]) -> None:
     if state.config.build_script is None:
         return
 
-    idmap_opt = ":rootidmap" if nspawn_version() >= 252 else ""
+    idmap_opt = ":rootidmap" if nspawn_id_map_supported() else ""
 
     with complete_step("Running build script…"):
         os.makedirs(install_dir(state), mode=0o755, exist_ok=True)