lib/PublicInbox/SearchIdx.pm  |  2 +-
 lib/PublicInbox/V2Writable.pm | 10 +++++++---
 t/init.t                      |  2 ++
 t/v2writable.t                | 16 ++++++++++++++++

diff --git a/lib/PublicInbox/SearchIdx.pm b/lib/PublicInbox/SearchIdx.pm
index 71469a9566e774c1c56e990e63e868bff110ed44..725bbd838075156f37b982384dd9bb5e077dab0f 100644
--- a/lib/PublicInbox/SearchIdx.pm
+++ b/lib/PublicInbox/SearchIdx.pm
@@ -817,7 +817,7 @@ sub _read_git_config_perm {
 	my ($self) = @_;
 	my @cmd = qw(config);
 	if ($self->{version} == 2) {
-		push @cmd, "--file=$self->{mainrepo}/inbox-config";
+		push @cmd, "--file=$self->{mainrepo}/all.git/config";
 	}
 	my $fh = $self->{git}->popen(@cmd, 'core.sharedRepository');
 	local $/ = "\n";
diff --git a/lib/PublicInbox/V2Writable.pm b/lib/PublicInbox/V2Writable.pm
index 31376db28bc4857b850804756b53f6bd496c2711..461432ea3ffbe695c3fe02f2a5e11b564408cd0f 100644
--- a/lib/PublicInbox/V2Writable.pm
+++ b/lib/PublicInbox/V2Writable.pm
@@ -244,15 +244,19 @@ 	my $git_dir = "$pfx/$new.git";
 	die "$git_dir exists\n" if -e $git_dir;
 	my @cmd = (qw(git init --bare -q), $git_dir);
 	PublicInbox::Import::run_die(\@cmd);
-	@cmd = (qw/git config/, "--file=$git_dir/config",
-			'repack.writeBitmaps', 'true');
-	PublicInbox::Import::run_die(\@cmd);
 
 	my $all = "$self->{-inbox}->{mainrepo}/all.git";
 	unless (-d $all) {
 		@cmd = (qw(git init --bare -q), $all);
 		PublicInbox::Import::run_die(\@cmd);
+		@cmd = (qw/git config/, "--file=$all/config",
+				'repack.writeBitmaps', 'true');
+		PublicInbox::Import::run_die(\@cmd);
 	}
+
+	@cmd = (qw/git config/, "--file=$git_dir/config",
+			'include.path', '../../all.git/config');
+	PublicInbox::Import::run_die(\@cmd);
 
 	my $alt = "$all/objects/info/alternates";
 	my $new_obj_dir = "../../git/$new.git/objects";
diff --git a/t/init.t b/t/init.t
index 54b90ec58415778587dfe164259f76f0d96c4133..6ae608e53ee7f0304647d59c598f59a6e2e55c05 100644
--- a/t/init.t
+++ b/t/init.t
@@ -38,6 +38,8 @@ 	is(system(@cmd), 0, 'public-inbox-init -V2 OK');
 	ok(-d "$tmpdir/v2list", 'v2list directory exists');
 	ok(-f "$tmpdir/v2list/msgmap.sqlite3", 'msgmap exists');
 	ok(-d "$tmpdir/v2list/all.git", 'catch-all.git directory exists');
+	@cmd = (qw(git config), "--file=$tmpdir/v2list/all.git/config",
+		qw(core.sharedRepository 0644));
 }
 
 done_testing();
diff --git a/t/v2writable.t b/t/v2writable.t
index bf8ae5e6c563514b5def130ea1b0810a4e06b6aa..2d35aca387d524b145e2fe58844e4a8391778d3d 100644
--- a/t/v2writable.t
+++ b/t/v2writable.t
@@ -32,6 +32,22 @@ );
 
 my $im = PublicInbox::V2Writable->new($ibx, 1);
 ok($im->add($mime), 'ordinary message added');
+
+if ('ensure git configs are correct') {
+	my @cmd = (qw(git config), "--file=$mainrepo/all.git/config",
+		qw(core.sharedRepository 0644));
+	is(system(@cmd), 0, "set sharedRepository in all.git");
+	my $git0 = PublicInbox::Git->new("$mainrepo/git/0.git");
+	my $fh = $git0->popen(qw(config core.sharedRepository));
+	my $v = eval { local $/; <$fh> };
+	chomp $v;
+	is($v, '0644', 'child repo inherited core.sharedRepository');
+	$fh = $git0->popen(qw(config --bool repack.writeBitmaps));
+	$v = eval { local $/; <$fh> };
+	chomp $v;
+	is($v, 'true', 'child repo inherited repack.writeBitmaps');
+}
+
 {
 	my @warn;
 	local $SIG{__WARN__} = sub { push @warn, @_ };