diff --git a/poky/meta/classes-recipe/externalsrc.bbclass b/poky/meta/classes-recipe/externalsrc.bbclass
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+++ b/poky/meta/classes-recipe/externalsrc.bbclass
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+# Copyright (C) 2012 Linux Foundation
+# Author: Richard Purdie
+# Some code and influence taken from srctree.bbclass:
+# Copyright (C) 2009 Chris Larson <clarson@kergoth.com>
+#
+# SPDX-License-Identifier: MIT
+#
+# externalsrc.bbclass enables use of an existing source tree, usually external to
+# the build system to build a piece of software rather than the usual fetch/unpack/patch
+# process.
+#
+# To use, add externalsrc to the global inherit and set EXTERNALSRC to point at the
+# directory you want to use containing the sources e.g. from local.conf for a recipe
+# called "myrecipe" you would do:
+#
+# INHERIT += "externalsrc"
+# EXTERNALSRC:pn-myrecipe = "/path/to/my/source/tree"
+#
+# In order to make this class work for both target and native versions (or with
+# multilibs/cross or other BBCLASSEXTEND variants), B is set to point to a separate
+# directory under the work directory (split source and build directories). This is
+# the default, but the build directory can be set to the source directory if
+# circumstances dictate by setting EXTERNALSRC_BUILD to the same value, e.g.:
+#
+# EXTERNALSRC_BUILD:pn-myrecipe = "/path/to/my/source/tree"
+#
+
+SRCTREECOVEREDTASKS ?= "do_patch do_unpack do_fetch"
+EXTERNALSRC_SYMLINKS ?= "oe-workdir:${WORKDIR} oe-logs:${T}"
+
+python () {
+    externalsrc = d.getVar('EXTERNALSRC')
+    externalsrcbuild = d.getVar('EXTERNALSRC_BUILD')
+
+    if externalsrc and not externalsrc.startswith("/"):
+        bb.error("EXTERNALSRC must be an absolute path")
+    if externalsrcbuild and not externalsrcbuild.startswith("/"):
+        bb.error("EXTERNALSRC_BUILD must be an absolute path")
+
+    # If this is the base recipe and EXTERNALSRC is set for it or any of its
+    # derivatives, then enable BB_DONT_CACHE to force the recipe to always be
+    # re-parsed so that the file-checksums function for do_compile is run every
+    # time.
+    bpn = d.getVar('BPN')
+    classextend = (d.getVar('BBCLASSEXTEND') or '').split()
+    if bpn == d.getVar('PN') or not classextend:
+        if (externalsrc or
+                ('native' in classextend and
+                 d.getVar('EXTERNALSRC:pn-%s-native' % bpn)) or
+                ('nativesdk' in classextend and
+                 d.getVar('EXTERNALSRC:pn-nativesdk-%s' % bpn)) or
+                ('cross' in classextend and
+                 d.getVar('EXTERNALSRC:pn-%s-cross' % bpn))):
+            d.setVar('BB_DONT_CACHE', '1')
+
+    if externalsrc:
+        import oe.recipeutils
+        import oe.path
+
+        d.setVar('S', externalsrc)
+        if externalsrcbuild:
+            d.setVar('B', externalsrcbuild)
+        else:
+            d.setVar('B', '${WORKDIR}/${BPN}-${PV}/')
+
+        local_srcuri = []
+        fetch = bb.fetch2.Fetch((d.getVar('SRC_URI') or '').split(), d)
+        for url in fetch.urls:
+            url_data = fetch.ud[url]
+            parm = url_data.parm
+            if (url_data.type == 'file' or
+                    url_data.type == 'npmsw' or url_data.type == 'crate' or
+                    'type' in parm and parm['type'] == 'kmeta'):
+                local_srcuri.append(url)
+
+        d.setVar('SRC_URI', ' '.join(local_srcuri))
+
+        # Dummy value because the default function can't be called with blank SRC_URI
+        d.setVar('SRCPV', '999')
+
+        if d.getVar('CONFIGUREOPT_DEPTRACK') == '--disable-dependency-tracking':
+            d.setVar('CONFIGUREOPT_DEPTRACK', '')
+
+        tasks = filter(lambda k: d.getVarFlag(k, "task"), d.keys())
+
+        for task in tasks:
+            if task.endswith("_setscene"):
+                # sstate is never going to work for external source trees, disable it
+                bb.build.deltask(task, d)
+            elif os.path.realpath(d.getVar('S')) == os.path.realpath(d.getVar('B')):
+                # Since configure will likely touch ${S}, ensure only we lock so one task has access at a time
+                d.appendVarFlag(task, "lockfiles", " ${S}/singletask.lock")
+
+            for funcname in [task, "base_" + task, "kernel_" + task]:
+                # We do not want our source to be wiped out, ever (kernel.bbclass does this for do_clean)
+                cleandirs = oe.recipeutils.split_var_value(d.getVarFlag(funcname, 'cleandirs', False) or '')
+                setvalue = False
+                for cleandir in cleandirs[:]:
+                    if oe.path.is_path_parent(externalsrc, d.expand(cleandir)):
+                        cleandirs.remove(cleandir)
+                        setvalue = True
+                if setvalue:
+                    d.setVarFlag(funcname, 'cleandirs', ' '.join(cleandirs))
+
+        fetch_tasks = ['do_fetch', 'do_unpack']
+        # If we deltask do_patch, there's no dependency to ensure do_unpack gets run, so add one
+        # Note that we cannot use d.appendVarFlag() here because deps is expected to be a list object, not a string
+        d.setVarFlag('do_configure', 'deps', (d.getVarFlag('do_configure', 'deps', False) or []) + ['do_unpack'])
+
+        for task in d.getVar("SRCTREECOVEREDTASKS").split():
+            if local_srcuri and task in fetch_tasks:
+                continue
+            bb.build.deltask(task, d)
+            if task == 'do_unpack':
+                # The reproducible build create_source_date_epoch_stamp function must
+                # be run after the source is available and before the
+                # do_deploy_source_date_epoch task.  In the normal case, it's attached
+                # to do_unpack as a postfuncs, but since we removed do_unpack (above)
+                # we need to move the function elsewhere.  The easiest thing to do is
+                # move it into the prefuncs of the do_deploy_source_date_epoch task.
+                # This is safe, as externalsrc runs with the source already unpacked.
+                d.prependVarFlag('do_deploy_source_date_epoch', 'prefuncs', 'create_source_date_epoch_stamp ')
+
+        d.prependVarFlag('do_compile', 'prefuncs', "externalsrc_compile_prefunc ")
+        d.prependVarFlag('do_configure', 'prefuncs', "externalsrc_configure_prefunc ")
+
+        d.setVarFlag('do_compile', 'file-checksums', '${@srctree_hash_files(d)}')
+        d.setVarFlag('do_configure', 'file-checksums', '${@srctree_configure_hash_files(d)}')
+
+        # We don't want the workdir to go away
+        d.appendVar('RM_WORK_EXCLUDE', ' ' + d.getVar('PN'))
+
+        bb.build.addtask('do_buildclean',
+                         'do_clean' if d.getVar('S') == d.getVar('B') else None,
+                         None, d)
+
+        # If B=S the same builddir is used even for different architectures.
+        # Thus, use a shared CONFIGURESTAMPFILE and STAMP directory so that
+        # change of do_configure task hash is correctly detected and stamps are
+        # invalidated if e.g. MACHINE changes.
+        if d.getVar('S') == d.getVar('B'):
+            configstamp = '${TMPDIR}/work-shared/${PN}/${EXTENDPE}${PV}-${PR}/configure.sstate'
+            d.setVar('CONFIGURESTAMPFILE', configstamp)
+            d.setVar('STAMP', '${STAMPS_DIR}/work-shared/${PN}/${EXTENDPE}${PV}-${PR}')
+            d.setVar('STAMPCLEAN', '${STAMPS_DIR}/work-shared/${PN}/*-*')
+}
+
+python externalsrc_configure_prefunc() {
+    s_dir = d.getVar('S')
+    # Create desired symlinks
+    symlinks = (d.getVar('EXTERNALSRC_SYMLINKS') or '').split()
+    newlinks = []
+    for symlink in symlinks:
+        symsplit = symlink.split(':', 1)
+        lnkfile = os.path.join(s_dir, symsplit[0])
+        target = d.expand(symsplit[1])
+        if len(symsplit) > 1:
+            if os.path.islink(lnkfile):
+                # Link already exists, leave it if it points to the right location already
+                if os.readlink(lnkfile) == target:
+                    continue
+                os.unlink(lnkfile)
+            elif os.path.exists(lnkfile):
+                # File/dir exists with same name as link, just leave it alone
+                continue
+            os.symlink(target, lnkfile)
+            newlinks.append(symsplit[0])
+    # Hide the symlinks from git
+    try:
+        git_exclude_file = os.path.join(s_dir, '.git/info/exclude')
+        if os.path.exists(git_exclude_file):
+            with open(git_exclude_file, 'r+') as efile:
+                elines = efile.readlines()
+                for link in newlinks:
+                    if link in elines or '/'+link in elines:
+                        continue
+                    efile.write('/' + link + '\n')
+    except IOError as ioe:
+        bb.note('Failed to hide EXTERNALSRC_SYMLINKS from git')
+}
+
+python externalsrc_compile_prefunc() {
+    # Make it obvious that this is happening, since forgetting about it could lead to much confusion
+    bb.plain('NOTE: %s: compiling from external source tree %s' % (d.getVar('PN'), d.getVar('EXTERNALSRC')))
+}
+
+do_buildclean[dirs] = "${S} ${B}"
+do_buildclean[nostamp] = "1"
+do_buildclean[doc] = "Call 'make clean' or equivalent in ${B}"
+externalsrc_do_buildclean() {
+	if [ -e Makefile -o -e makefile -o -e GNUmakefile ]; then
+		rm -f ${@' '.join([x.split(':')[0] for x in (d.getVar('EXTERNALSRC_SYMLINKS') or '').split()])}
+		if [ "${CLEANBROKEN}" != "1" ]; then
+			oe_runmake clean || die "make failed"
+		fi
+	else
+		bbnote "nothing to do - no makefile found"
+	fi
+}
+
+def srctree_hash_files(d, srcdir=None):
+    import shutil
+    import subprocess
+    import tempfile
+    import hashlib
+
+    s_dir = srcdir or d.getVar('EXTERNALSRC')
+    git_dir = None
+
+    try:
+        git_dir = os.path.join(s_dir,
+            subprocess.check_output(['git', '-C', s_dir, 'rev-parse', '--git-dir'], stderr=subprocess.DEVNULL).decode("utf-8").rstrip())
+        top_git_dir = os.path.join(s_dir, subprocess.check_output(['git', '-C', d.getVar("TOPDIR"), 'rev-parse', '--git-dir'],
+            stderr=subprocess.DEVNULL).decode("utf-8").rstrip())
+        if git_dir == top_git_dir:
+            git_dir = None
+    except subprocess.CalledProcessError:
+        pass
+
+    ret = " "
+    if git_dir is not None:
+        oe_hash_file = os.path.join(git_dir, 'oe-devtool-tree-sha1-%s' % d.getVar('PN'))
+        with tempfile.NamedTemporaryFile(prefix='oe-devtool-index') as tmp_index:
+            # Clone index
+            shutil.copyfile(os.path.join(git_dir, 'index'), tmp_index.name)
+            # Update our custom index
+            env = os.environ.copy()
+            env['GIT_INDEX_FILE'] = tmp_index.name
+            subprocess.check_output(['git', 'add', '-A', '.'], cwd=s_dir, env=env)
+            git_sha1 = subprocess.check_output(['git', 'write-tree'], cwd=s_dir, env=env).decode("utf-8")
+            submodule_helper = subprocess.check_output(['git', 'submodule--helper', 'list'], cwd=s_dir, env=env).decode("utf-8")
+            for line in submodule_helper.splitlines():
+                module_dir = os.path.join(s_dir, line.rsplit(maxsplit=1)[1])
+                if os.path.isdir(module_dir):
+                    proc = subprocess.Popen(['git', 'add', '-A', '.'], cwd=module_dir, env=env, stdout=subprocess.DEVNULL, stderr=subprocess.DEVNULL)
+                    proc.communicate()
+                    proc = subprocess.Popen(['git', 'write-tree'], cwd=module_dir, env=env, stdout=subprocess.PIPE, stderr=subprocess.DEVNULL)
+                    stdout, _ = proc.communicate()
+                    git_sha1 += stdout.decode("utf-8")
+            sha1 = hashlib.sha1(git_sha1.encode("utf-8")).hexdigest()
+        with open(oe_hash_file, 'w') as fobj:
+            fobj.write(sha1)
+        ret = oe_hash_file + ':True'
+    else:
+        ret = s_dir + '/*:True'
+    return ret
+
+def srctree_configure_hash_files(d):
+    """
+    Get the list of files that should trigger do_configure to re-execute,
+    based on the value of CONFIGURE_FILES
+    """
+    in_files = (d.getVar('CONFIGURE_FILES') or '').split()
+    out_items = []
+    search_files = []
+    for entry in in_files:
+        if entry.startswith('/'):
+            out_items.append('%s:%s' % (entry, os.path.exists(entry)))
+        else:
+            search_files.append(entry)
+    if search_files:
+        s_dir = d.getVar('EXTERNALSRC')
+        for root, _, files in os.walk(s_dir):
+            for f in files:
+                if f in search_files:
+                    out_items.append('%s:True' % os.path.join(root, f))
+    return ' '.join(out_items)
+
+EXPORT_FUNCTIONS do_buildclean