[PATCH v2 0/2] bootconfig: Handle an empty value

[PATCH v2 0/2] bootconfig: Handle an empty value

[Masami Hiramatsu (Google)]

This is the 2nd version of the update of the bootconfig parser to
make it handle an empty value which is terminated by a newline or
a comment. The previous version is here:


In this version I decided to make this change as an update instead
of a fix, since this can change the syntax rule which has been
accepted. In the previous change, it does not handle the array
correctly. This version fixes it[1/2].

Also, I added another patch to improve the test[2/2]. Previously
it just check the parse error, but it did not check whether the
good examples are formatted as it is expected. New test compares
the output so that we can ensure it is parsed as expected.

Thank you,

---

Masami Hiramatsu (Google) (2):
      bootconfig: Terminate value search if it hits a newline
      bootconfig: Check the parsed output of the good examples


 .../samples/exp-good-array-space-comment.bconf     |    1 +
 .../samples/exp-good-comment-after-value.bconf     |    1 +
 .../bootconfig/samples/exp-good-mixed-append.bconf |    2 ++
 tools/bootconfig/samples/exp-good-mixed-kv1.bconf  |    2 ++
 tools/bootconfig/samples/exp-good-mixed-kv2.bconf  |    2 ++
 tools/bootconfig/samples/exp-good-mixed-kv3.bconf  |    5 +++++
 .../samples/exp-good-mixed-override.bconf          |    2 ++
 tools/bootconfig/samples/exp-good-override.bconf   |    4 ++++
 tools/bootconfig/samples/exp-good-printables.bconf |    2 ++
 tools/bootconfig/samples/exp-good-simple.bconf     |    8 ++++++++
 tools/bootconfig/samples/exp-good-single.bconf     |    3 +++
 .../samples/exp-good-space-after-value.bconf       |    1 +
 tools/bootconfig/samples/exp-good-tree.bconf       |    8 ++++++++
 .../samples/good-array-space-comment.bconf         |    3 +--
 tools/bootconfig/test-bootconfig.sh                |    3 +++
 15 files changed, 45 insertions(+), 2 deletions(-)
 create mode 100644 tools/bootconfig/samples/exp-good-array-space-comment.bconf
 create mode 100644 tools/bootconfig/samples/exp-good-comment-after-value.bconf
 create mode 100644 tools/bootconfig/samples/exp-good-mixed-append.bconf
 create mode 100644 tools/bootconfig/samples/exp-good-mixed-kv1.bconf
 create mode 100644 tools/bootconfig/samples/exp-good-mixed-kv2.bconf
 create mode 100644 tools/bootconfig/samples/exp-good-mixed-kv3.bconf
 create mode 100644 tools/bootconfig/samples/exp-good-mixed-override.bconf
 create mode 100644 tools/bootconfig/samples/exp-good-override.bconf
 create mode 100644 tools/bootconfig/samples/exp-good-printables.bconf
 create mode 100644 tools/bootconfig/samples/exp-good-simple.bconf
 create mode 100644 tools/bootconfig/samples/exp-good-single.bconf
 create mode 100644 tools/bootconfig/samples/exp-good-space-after-value.bconf
 create mode 100644 tools/bootconfig/samples/exp-good-tree.bconf

--
Masami Hiramatsu (Google) <mhiramat@google.com>

[PATCH v2 1/2] bootconfig: Terminate value search if it hits a newline

[Masami Hiramatsu (Google)]

From: Masami Hiramatsu (Google) <mhiramat@kernel.org>

Terminate the value search for a key if it hits a newline and make
the value empty.

When we pass a bootconfig with an empty value terminated by the
newline, like below::

  foo =
  bar = value

Current bootconfig interprets it as a single entry::

  foo = "bar = value";

The Documentation/admin-guide/bootconfig.rst defines the value
itself is terminated by newline:

  The value has to be terminated by semi-colon (``;``) or newline (``\n``).

but it does not define when the value search is terminated.
This changes the behavior to more line-oriented, so that it can
clear how it is working.

- The value search of key-value pair will be terminated by a comment
  or newline.
- The value search of an array will continue beyond comments and
  newlines.

Thus, with this update, the above example is interpreted as::

  foo = "";
  bar = "value";

And the below example will cause a syntax error because "bar" is expected
as a key but it has ','.

  foo =
    bar, buz

According to this change, one wrong example config is updated.

Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
---
 Changes in v2:
  - Fix to handle multi-line array case correctly.
  - Make this as a spec update, not fix.
---
 .../samples/good-array-space-comment.bconf         |    3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/Documentation/admin-guide/bootconfig.rst b/Documentation/admin-guide/bootconfig.rst
index 7a86042c9b6d..843b24b8de88 100644
--- a/Documentation/admin-guide/bootconfig.rst
+++ b/Documentation/admin-guide/bootconfig.rst
@@ -20,18 +20,26 @@ Config File Syntax
 
 The boot config syntax is a simple structured key-value. Each key consists
 of dot-connected-words, and key and value are connected by ``=``. The value
-has to be terminated by semi-colon (``;``) or newline (``\n``).
-For array value, array entries are separated by comma (``,``). ::
-
-  KEY[.WORD[...]] = VALUE[, VALUE2[...]][;]
-
-Unlike the kernel command line syntax, spaces are OK around the comma and ``=``.
+string has to be terminated by the following delimiters described below.
 
 Each key word must contain only alphabets, numbers, dash (``-``) or underscore
 (``_``). And each value only contains printable characters or spaces except
 for delimiters such as semi-colon (``;``), new-line (``\n``), comma (``,``),
 hash (``#``) and closing brace (``}``).
 
+If the ``=`` is followed by whitespace up to one of these delimiters, the
+key is assigned an empty value.
+
+For arrays, the array values are comma (``,``) separated, and comments and
+line breaks with newline (``\n``) are allowed between array values for
+readability. Thus the first entry of the array must be the same line of the
+key.::
+
+  KEY[.WORD[...]] = VALUE[, VALUE2[...]][;]
+
+Unlike the kernel command line syntax, white spaces (including tabs) are
+ignored around the comma and ``=``.
+
 If you want to use those delimiters in a value, you can use either double-
 quotes (``"VALUE"``) or single-quotes (``'VALUE'``) to quote it. Note that
 you can not escape these quotes.
@@ -138,8 +146,8 @@ This is parsed as below::
  foo = value
  bar = 1, 2, 3
 
-Note that you can not put a comment between value and delimiter(``,`` or
-``;``). This means following config has a syntax error ::
+Note that you can NOT put a comment or a newline between value and delimiter
+(``,`` or ``;``). This means following config has a syntax error ::
 
  key = 1 # comment
        ,2
diff --git a/lib/bootconfig.c b/lib/bootconfig.c
index 81f29c29f47b..c210fb8b1e85 100644
--- a/lib/bootconfig.c
+++ b/lib/bootconfig.c
@@ -557,17 +557,13 @@ static int __init __xbc_close_brace(char *p)
 /*
  * Return delimiter or error, no node added. As same as lib/cmdline.c,
  * you can use " around spaces, but can't escape " for value.
+ * *@__v must point real value string. (not including spaces before value.)
  */
 static int __init __xbc_parse_value(char **__v, char **__n)
 {
 	char *p, *v = *__v;
 	int c, quotes = 0;
 
-	v = skip_spaces(v);
-	while (*v == '#') {
-		v = skip_comment(v);
-		v = skip_spaces(v);
-	}
 	if (*v == '"' || *v == '\'') {
 		quotes = *v;
 		v++;
@@ -617,6 +613,13 @@ static int __init xbc_parse_array(char **__v)
 		last_parent = xbc_node_get_child(last_parent);
 
 	do {
+		/* Search the next array value beyond comments and empty lines */
+		next = skip_spaces(*__v);
+		while (*next == '#') {
+			next = skip_comment(next);
+			next = skip_spaces(next);
+		}
+		*__v = next;
 		c = __xbc_parse_value(__v, &next);
 		if (c < 0)
 			return c;
@@ -701,9 +704,17 @@ static int __init xbc_parse_kv(char **k, char *v, int op)
 	if (ret)
 		return ret;
 
-	c = __xbc_parse_value(&v, &next);
-	if (c < 0)
-		return c;
+	v = skip_spaces_until_newline(v);
+	/* If there is a comment, this has an mpty value. */
+	if (*v == '#') {
+		next = skip_comment(v);
+		*v = '\0';
+		c = '\n';
+	} else {
+		c = __xbc_parse_value(&v, &next);
+		if (c < 0)
+			return c;
+	}
 
 	child = xbc_node_get_child(last_parent);
 	if (child && xbc_node_is_value(child)) {
diff --git a/tools/bootconfig/samples/good-array-space-comment.bconf b/tools/bootconfig/samples/good-array-space-comment.bconf
index 45b938dc0695..416fa2ed4109 100644
--- a/tools/bootconfig/samples/good-array-space-comment.bconf
+++ b/tools/bootconfig/samples/good-array-space-comment.bconf
@@ -1,4 +1,3 @@
-key =	# comment
-	"value1",	  # comment1
+key = "value1",	  # comment1
 	"value2"	 , # comment2
 	"value3"

[PATCH v2 2/2] bootconfig: Check the parsed output of the good examples

[Masami Hiramatsu (Google)]

From: Masami Hiramatsu (Google) <mhiramat@kernel.org>

Check whether the parsed output of the good example configs are
the same as expected.

Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
---
 .../samples/exp-good-array-space-comment.bconf     |    1 +
 .../samples/exp-good-comment-after-value.bconf     |    1 +
 .../bootconfig/samples/exp-good-mixed-append.bconf |    2 ++
 tools/bootconfig/samples/exp-good-mixed-kv1.bconf  |    2 ++
 tools/bootconfig/samples/exp-good-mixed-kv2.bconf  |    2 ++
 tools/bootconfig/samples/exp-good-mixed-kv3.bconf  |    5 +++++
 .../samples/exp-good-mixed-override.bconf          |    2 ++
 tools/bootconfig/samples/exp-good-override.bconf   |    4 ++++
 tools/bootconfig/samples/exp-good-printables.bconf |    2 ++
 tools/bootconfig/samples/exp-good-simple.bconf     |    8 ++++++++
 tools/bootconfig/samples/exp-good-single.bconf     |    3 +++
 .../samples/exp-good-space-after-value.bconf       |    1 +
 tools/bootconfig/samples/exp-good-tree.bconf       |    8 ++++++++
 tools/bootconfig/test-bootconfig.sh                |    3 +++
 14 files changed, 44 insertions(+)
 create mode 100644 tools/bootconfig/samples/exp-good-array-space-comment.bconf
 create mode 100644 tools/bootconfig/samples/exp-good-comment-after-value.bconf
 create mode 100644 tools/bootconfig/samples/exp-good-mixed-append.bconf
 create mode 100644 tools/bootconfig/samples/exp-good-mixed-kv1.bconf
 create mode 100644 tools/bootconfig/samples/exp-good-mixed-kv2.bconf
 create mode 100644 tools/bootconfig/samples/exp-good-mixed-kv3.bconf
 create mode 100644 tools/bootconfig/samples/exp-good-mixed-override.bconf
 create mode 100644 tools/bootconfig/samples/exp-good-override.bconf
 create mode 100644 tools/bootconfig/samples/exp-good-printables.bconf
 create mode 100644 tools/bootconfig/samples/exp-good-simple.bconf
 create mode 100644 tools/bootconfig/samples/exp-good-single.bconf
 create mode 100644 tools/bootconfig/samples/exp-good-space-after-value.bconf
 create mode 100644 tools/bootconfig/samples/exp-good-tree.bconf

diff --git a/tools/bootconfig/samples/exp-good-array-space-comment.bconf b/tools/bootconfig/samples/exp-good-array-space-comment.bconf
new file mode 100644
index 000000000000..8d3278fa6af5
--- /dev/null
+++ b/tools/bootconfig/samples/exp-good-array-space-comment.bconf
@@ -0,0 +1 @@
+key = "value1", "value2", "value3";
diff --git a/tools/bootconfig/samples/exp-good-comment-after-value.bconf b/tools/bootconfig/samples/exp-good-comment-after-value.bconf
new file mode 100644
index 000000000000..a8e8450db3c0
--- /dev/null
+++ b/tools/bootconfig/samples/exp-good-comment-after-value.bconf
@@ -0,0 +1 @@
+key = "value";
diff --git a/tools/bootconfig/samples/exp-good-mixed-append.bconf b/tools/bootconfig/samples/exp-good-mixed-append.bconf
new file mode 100644
index 000000000000..c2b407901ddd
--- /dev/null
+++ b/tools/bootconfig/samples/exp-good-mixed-append.bconf
@@ -0,0 +1,2 @@
+key = "foo", "bar";
+keyx.subkey = "value";
diff --git a/tools/bootconfig/samples/exp-good-mixed-kv1.bconf b/tools/bootconfig/samples/exp-good-mixed-kv1.bconf
new file mode 100644
index 000000000000..8346287d9251
--- /dev/null
+++ b/tools/bootconfig/samples/exp-good-mixed-kv1.bconf
@@ -0,0 +1,2 @@
+key = "value";
+key.subkey = "another-value";
diff --git a/tools/bootconfig/samples/exp-good-mixed-kv2.bconf b/tools/bootconfig/samples/exp-good-mixed-kv2.bconf
new file mode 100644
index 000000000000..40c6232c7cdd
--- /dev/null
+++ b/tools/bootconfig/samples/exp-good-mixed-kv2.bconf
@@ -0,0 +1,2 @@
+key = "another-value";
+key.subkey = "value";
diff --git a/tools/bootconfig/samples/exp-good-mixed-kv3.bconf b/tools/bootconfig/samples/exp-good-mixed-kv3.bconf
new file mode 100644
index 000000000000..8368a7bef60a
--- /dev/null
+++ b/tools/bootconfig/samples/exp-good-mixed-kv3.bconf
@@ -0,0 +1,5 @@
+key = "value";
+key {
+	subkey1;
+	subkey2 = "foo";
+}
diff --git a/tools/bootconfig/samples/exp-good-mixed-override.bconf b/tools/bootconfig/samples/exp-good-mixed-override.bconf
new file mode 100644
index 000000000000..58757712ca45
--- /dev/null
+++ b/tools/bootconfig/samples/exp-good-mixed-override.bconf
@@ -0,0 +1,2 @@
+key = "value2";
+key.foo = "bar";
diff --git a/tools/bootconfig/samples/exp-good-override.bconf b/tools/bootconfig/samples/exp-good-override.bconf
new file mode 100644
index 000000000000..00bbd30e99ae
--- /dev/null
+++ b/tools/bootconfig/samples/exp-good-override.bconf
@@ -0,0 +1,4 @@
+key {
+	word = "2", "3";
+	new.word = "new";
+}
diff --git a/tools/bootconfig/samples/exp-good-printables.bconf b/tools/bootconfig/samples/exp-good-printables.bconf
new file mode 100644
index 000000000000..5981d304eacb
--- /dev/null
+++ b/tools/bootconfig/samples/exp-good-printables.bconf
@@ -0,0 +1,2 @@
+key = "	
+\v\f !#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}~";
diff --git a/tools/bootconfig/samples/exp-good-simple.bconf b/tools/bootconfig/samples/exp-good-simple.bconf
new file mode 100644
index 000000000000..d17f39421c86
--- /dev/null
+++ b/tools/bootconfig/samples/exp-good-simple.bconf
@@ -0,0 +1,8 @@
+key {
+	word1 = "1";
+	word2 = "2";
+	word3 = "3";
+	word4 = "4";
+	word5 = "5";
+	word6 = "6";
+}
diff --git a/tools/bootconfig/samples/exp-good-single.bconf b/tools/bootconfig/samples/exp-good-single.bconf
new file mode 100644
index 000000000000..01196910d7f4
--- /dev/null
+++ b/tools/bootconfig/samples/exp-good-single.bconf
@@ -0,0 +1,3 @@
+key = "1";
+key2 = "2";
+key3 = "alpha", "beta";
diff --git a/tools/bootconfig/samples/exp-good-space-after-value.bconf b/tools/bootconfig/samples/exp-good-space-after-value.bconf
new file mode 100644
index 000000000000..a8e8450db3c0
--- /dev/null
+++ b/tools/bootconfig/samples/exp-good-space-after-value.bconf
@@ -0,0 +1 @@
+key = "value";
diff --git a/tools/bootconfig/samples/exp-good-tree.bconf b/tools/bootconfig/samples/exp-good-tree.bconf
new file mode 100644
index 000000000000..b711d38d86fd
--- /dev/null
+++ b/tools/bootconfig/samples/exp-good-tree.bconf
@@ -0,0 +1,8 @@
+key {
+	word.tree.value = "0";
+	word2.tree.value = "1", "2";
+}
+other.tree {
+	value = "2";
+	value2 = "3";
+}
diff --git a/tools/bootconfig/test-bootconfig.sh b/tools/bootconfig/test-bootconfig.sh
index 7594659af1e1..be9bd18b1d56 100755
--- a/tools/bootconfig/test-bootconfig.sh
+++ b/tools/bootconfig/test-bootconfig.sh
@@ -179,6 +179,9 @@ done
 echo "=== expected success cases ==="
 for i in samples/good-* ; do
   xpass $BOOTCONF -a $i $INITRD
+  x="samples/exp-"`basename $i`
+  $BOOTCONF $i > $TEMPCONF
+  xpass diff $x $TEMPCONF
 done
 
 

Re: [PATCH v2 1/2] bootconfig: Terminate value search if it hits a newline

[Julius Werner]

Reviewed-by: Julius Werner <jwerner@chromium.org>

Thank you!

Re: [PATCH v2 1/2] bootconfig: Terminate value search if it hits a newline

[Steven Rostedt]

On Wed,  4 Feb 2026 17:33:48 +0900
"Masami Hiramatsu (Google)" <mhiramat@kernel.org> wrote:

> From: Masami Hiramatsu (Google) <mhiramat@kernel.org>
> 
> Terminate the value search for a key if it hits a newline and make
> the value empty.
> 
> When we pass a bootconfig with an empty value terminated by the
> newline, like below::
> 
>   foo =
>   bar = value
> 
> Current bootconfig interprets it as a single entry::
> 
>   foo = "bar = value";
> 
> The Documentation/admin-guide/bootconfig.rst defines the value
> itself is terminated by newline:
> 
>   The value has to be terminated by semi-colon (``;``) or newline (``\n``).
> 
> but it does not define when the value search is terminated.
> This changes the behavior to more line-oriented, so that it can

     to be more line-oriented

> clear how it is working.

  so that it is clearer in how it works.


> 
> - The value search of key-value pair will be terminated by a comment
>   or newline.
> - The value search of an array will continue beyond comments and
>   newlines.
> 
> Thus, with this update, the above example is interpreted as::
> 
>   foo = "";
>   bar = "value";
> 
> And the below example will cause a syntax error because "bar" is expected
> as a key but it has ','.
> 
>   foo =
>     bar, buz
> 
> According to this change, one wrong example config is updated.
> 
> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
> ---
>  Changes in v2:
>   - Fix to handle multi-line array case correctly.
>   - Make this as a spec update, not fix.
> ---
>  .../samples/good-array-space-comment.bconf         |    3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
> 
> diff --git a/Documentation/admin-guide/bootconfig.rst b/Documentation/admin-guide/bootconfig.rst
> index 7a86042c9b6d..843b24b8de88 100644
> --- a/Documentation/admin-guide/bootconfig.rst
> +++ b/Documentation/admin-guide/bootconfig.rst
> @@ -20,18 +20,26 @@ Config File Syntax
>  
>  The boot config syntax is a simple structured key-value. Each key consists
>  of dot-connected-words, and key and value are connected by ``=``. The value
> -has to be terminated by semi-colon (``;``) or newline (``\n``).
> -For array value, array entries are separated by comma (``,``). ::
> -
> -  KEY[.WORD[...]] = VALUE[, VALUE2[...]][;]
> -
> -Unlike the kernel command line syntax, spaces are OK around the comma and ``=``.
> +string has to be terminated by the following delimiters described below.
>  
>  Each key word must contain only alphabets, numbers, dash (``-``) or underscore
>  (``_``). And each value only contains printable characters or spaces except
>  for delimiters such as semi-colon (``;``), new-line (``\n``), comma (``,``),
>  hash (``#``) and closing brace (``}``).
>  
> +If the ``=`` is followed by whitespace up to one of these delimiters, the
> +key is assigned an empty value.
> +
> +For arrays, the array values are comma (``,``) separated, and comments and
> +line breaks with newline (``\n``) are allowed between array values for
> +readability. Thus the first entry of the array must be the same line of the

                         must be on the same line as the key.

> +key.::
> +
> +  KEY[.WORD[...]] = VALUE[, VALUE2[...]][;]
> +
> +Unlike the kernel command line syntax, white spaces (including tabs) are
> +ignored around the comma and ``=``.
> +
>  If you want to use those delimiters in a value, you can use either double-
>  quotes (``"VALUE"``) or single-quotes (``'VALUE'``) to quote it. Note that
>  you can not escape these quotes.
> @@ -138,8 +146,8 @@ This is parsed as below::
>   foo = value
>   bar = 1, 2, 3
>  
> -Note that you can not put a comment between value and delimiter(``,`` or
> -``;``). This means following config has a syntax error ::
> +Note that you can NOT put a comment or a newline between value and delimiter
> +(``,`` or ``;``). This means following config has a syntax error ::
>  
>   key = 1 # comment
>         ,2
> diff --git a/lib/bootconfig.c b/lib/bootconfig.c
> index 81f29c29f47b..c210fb8b1e85 100644
> --- a/lib/bootconfig.c
> +++ b/lib/bootconfig.c
> @@ -557,17 +557,13 @@ static int __init __xbc_close_brace(char *p)
>  /*
>   * Return delimiter or error, no node added. As same as lib/cmdline.c,
>   * you can use " around spaces, but can't escape " for value.
> + * *@__v must point real value string. (not including spaces before value.)
>   */
>  static int __init __xbc_parse_value(char **__v, char **__n)
>  {
>  	char *p, *v = *__v;
>  	int c, quotes = 0;
>  
> -	v = skip_spaces(v);
> -	while (*v == '#') {
> -		v = skip_comment(v);
> -		v = skip_spaces(v);
> -	}
>  	if (*v == '"' || *v == '\'') {
>  		quotes = *v;
>  		v++;
> @@ -617,6 +613,13 @@ static int __init xbc_parse_array(char **__v)
>  		last_parent = xbc_node_get_child(last_parent);
>  
>  	do {
> +		/* Search the next array value beyond comments and empty lines */
> +		next = skip_spaces(*__v);
> +		while (*next == '#') {
> +			next = skip_comment(next);
> +			next = skip_spaces(next);
> +		}
> +		*__v = next;
>  		c = __xbc_parse_value(__v, &next);
>  		if (c < 0)
>  			return c;
> @@ -701,9 +704,17 @@ static int __init xbc_parse_kv(char **k, char *v, int op)
>  	if (ret)
>  		return ret;
>  
> -	c = __xbc_parse_value(&v, &next);
> -	if (c < 0)
> -		return c;
> +	v = skip_spaces_until_newline(v);
> +	/* If there is a comment, this has an mpty value. */

                                             empty value

-- Steve

> +	if (*v == '#') {
> +		next = skip_comment(v);
> +		*v = '\0';
> +		c = '\n';
> +	} else {
> +		c = __xbc_parse_value(&v, &next);
> +		if (c < 0)
> +			return c;
> +	}
>  
>  	child = xbc_node_get_child(last_parent);
>  	if (child && xbc_node_is_value(child)) {
> diff --git a/tools/bootconfig/samples/good-array-space-comment.bconf b/tools/bootconfig/samples/good-array-space-comment.bconf
> index 45b938dc0695..416fa2ed4109 100644
> --- a/tools/bootconfig/samples/good-array-space-comment.bconf
> +++ b/tools/bootconfig/samples/good-array-space-comment.bconf
> @@ -1,4 +1,3 @@
> -key =	# comment
> -	"value1",	  # comment1
> +key = "value1",	  # comment1
>  	"value2"	 , # comment2
>  	"value3"

Re: [PATCH v2 2/2] bootconfig: Check the parsed output of the good examples

[Steven Rostedt]

On Wed,  4 Feb 2026 17:33:58 +0900
"Masami Hiramatsu (Google)" <mhiramat@kernel.org> wrote:

> From: Masami Hiramatsu (Google) <mhiramat@kernel.org>
> 
> Check whether the parsed output of the good example configs are
> the same as expected.
> 
> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>

Tested-by: Steven Rostedt (Google) <rostedt@goodmis.org>

-- Steve

Re: [PATCH v2 1/2] bootconfig: Terminate value search if it hits a newline

[Masami Hiramatsu]

On Wed, 4 Feb 2026 17:20:57 -0500
Steven Rostedt <rostedt@goodmis.org> wrote:

> On Wed,  4 Feb 2026 17:33:48 +0900
> "Masami Hiramatsu (Google)" <mhiramat@kernel.org> wrote:
> 
> > From: Masami Hiramatsu (Google) <mhiramat@kernel.org>
> > 
> > Terminate the value search for a key if it hits a newline and make
> > the value empty.
> > 
> > When we pass a bootconfig with an empty value terminated by the
> > newline, like below::
> > 
> >   foo =
> >   bar = value
> > 
> > Current bootconfig interprets it as a single entry::
> > 
> >   foo = "bar = value";
> > 
> > The Documentation/admin-guide/bootconfig.rst defines the value
> > itself is terminated by newline:
> > 
> >   The value has to be terminated by semi-colon (``;``) or newline (``\n``).
> > 
> > but it does not define when the value search is terminated.
> > This changes the behavior to more line-oriented, so that it can
> 
>      to be more line-oriented
> 
> > clear how it is working.
> 
>   so that it is clearer in how it works.
> 

OK,

> 
> > 
> > - The value search of key-value pair will be terminated by a comment
> >   or newline.
> > - The value search of an array will continue beyond comments and
> >   newlines.
> > 
> > Thus, with this update, the above example is interpreted as::
> > 
> >   foo = "";
> >   bar = "value";
> > 
> > And the below example will cause a syntax error because "bar" is expected
> > as a key but it has ','.
> > 
> >   foo =
> >     bar, buz
> > 
> > According to this change, one wrong example config is updated.
> > 
> > Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
> > ---
> >  Changes in v2:
> >   - Fix to handle multi-line array case correctly.
> >   - Make this as a spec update, not fix.
> > ---
> >  .../samples/good-array-space-comment.bconf         |    3 +--
> >  1 file changed, 1 insertion(+), 2 deletions(-)
> > 
> > diff --git a/Documentation/admin-guide/bootconfig.rst b/Documentation/admin-guide/bootconfig.rst
> > index 7a86042c9b6d..843b24b8de88 100644
> > --- a/Documentation/admin-guide/bootconfig.rst
> > +++ b/Documentation/admin-guide/bootconfig.rst
> > @@ -20,18 +20,26 @@ Config File Syntax
> >  
> >  The boot config syntax is a simple structured key-value. Each key consists
> >  of dot-connected-words, and key and value are connected by ``=``. The value
> > -has to be terminated by semi-colon (``;``) or newline (``\n``).
> > -For array value, array entries are separated by comma (``,``). ::
> > -
> > -  KEY[.WORD[...]] = VALUE[, VALUE2[...]][;]
> > -
> > -Unlike the kernel command line syntax, spaces are OK around the comma and ``=``.
> > +string has to be terminated by the following delimiters described below.
> >  
> >  Each key word must contain only alphabets, numbers, dash (``-``) or underscore
> >  (``_``). And each value only contains printable characters or spaces except
> >  for delimiters such as semi-colon (``;``), new-line (``\n``), comma (``,``),
> >  hash (``#``) and closing brace (``}``).
> >  
> > +If the ``=`` is followed by whitespace up to one of these delimiters, the
> > +key is assigned an empty value.
> > +
> > +For arrays, the array values are comma (``,``) separated, and comments and
> > +line breaks with newline (``\n``) are allowed between array values for
> > +readability. Thus the first entry of the array must be the same line of the
> 
>                          must be on the same line as the key.

OK.

> 
> > +key.::
> > +
> > +  KEY[.WORD[...]] = VALUE[, VALUE2[...]][;]
> > +
> > +Unlike the kernel command line syntax, white spaces (including tabs) are
> > +ignored around the comma and ``=``.
> > +
> >  If you want to use those delimiters in a value, you can use either double-
> >  quotes (``"VALUE"``) or single-quotes (``'VALUE'``) to quote it. Note that
> >  you can not escape these quotes.
> > @@ -138,8 +146,8 @@ This is parsed as below::
> >   foo = value
> >   bar = 1, 2, 3
> >  
> > -Note that you can not put a comment between value and delimiter(``,`` or
> > -``;``). This means following config has a syntax error ::
> > +Note that you can NOT put a comment or a newline between value and delimiter
> > +(``,`` or ``;``). This means following config has a syntax error ::
> >  
> >   key = 1 # comment
> >         ,2
> > diff --git a/lib/bootconfig.c b/lib/bootconfig.c
> > index 81f29c29f47b..c210fb8b1e85 100644
> > --- a/lib/bootconfig.c
> > +++ b/lib/bootconfig.c
> > @@ -557,17 +557,13 @@ static int __init __xbc_close_brace(char *p)
> >  /*
> >   * Return delimiter or error, no node added. As same as lib/cmdline.c,
> >   * you can use " around spaces, but can't escape " for value.
> > + * *@__v must point real value string. (not including spaces before value.)
> >   */
> >  static int __init __xbc_parse_value(char **__v, char **__n)
> >  {
> >  	char *p, *v = *__v;
> >  	int c, quotes = 0;
> >  
> > -	v = skip_spaces(v);
> > -	while (*v == '#') {
> > -		v = skip_comment(v);
> > -		v = skip_spaces(v);
> > -	}
> >  	if (*v == '"' || *v == '\'') {
> >  		quotes = *v;
> >  		v++;
> > @@ -617,6 +613,13 @@ static int __init xbc_parse_array(char **__v)
> >  		last_parent = xbc_node_get_child(last_parent);
> >  
> >  	do {
> > +		/* Search the next array value beyond comments and empty lines */
> > +		next = skip_spaces(*__v);
> > +		while (*next == '#') {
> > +			next = skip_comment(next);
> > +			next = skip_spaces(next);
> > +		}
> > +		*__v = next;
> >  		c = __xbc_parse_value(__v, &next);
> >  		if (c < 0)
> >  			return c;
> > @@ -701,9 +704,17 @@ static int __init xbc_parse_kv(char **k, char *v, int op)
> >  	if (ret)
> >  		return ret;
> >  
> > -	c = __xbc_parse_value(&v, &next);
> > -	if (c < 0)
> > -		return c;
> > +	v = skip_spaces_until_newline(v);
> > +	/* If there is a comment, this has an mpty value. */
> 
>                                              empty value

Thanks!

> 
> -- Steve
> 
> > +	if (*v == '#') {
> > +		next = skip_comment(v);
> > +		*v = '\0';
> > +		c = '\n';
> > +	} else {
> > +		c = __xbc_parse_value(&v, &next);
> > +		if (c < 0)
> > +			return c;
> > +	}
> >  
> >  	child = xbc_node_get_child(last_parent);
> >  	if (child && xbc_node_is_value(child)) {
> > diff --git a/tools/bootconfig/samples/good-array-space-comment.bconf b/tools/bootconfig/samples/good-array-space-comment.bconf
> > index 45b938dc0695..416fa2ed4109 100644
> > --- a/tools/bootconfig/samples/good-array-space-comment.bconf
> > +++ b/tools/bootconfig/samples/good-array-space-comment.bconf
> > @@ -1,4 +1,3 @@
> > -key =	# comment
> > -	"value1",	  # comment1
> > +key = "value1",	  # comment1
> >  	"value2"	 , # comment2
> >  	"value3"
> 
> 


-- 
Masami Hiramatsu (Google) <mhiramat@kernel.org>