diff --git a/Documentation/git-format-patch.txt b/Documentation/git-format-patch.txt
index 3e49bf221087..f10fa6527f5f 100644
--- a/Documentation/git-format-patch.txt
+++ b/Documentation/git-format-patch.txt
@@ -22,6 +22,7 @@ SYNOPSIS
 		   [--cover-from-description=<mode>]
 		   [--rfc] [--subject-prefix=<subject prefix>]
 		   [(--reroll-count|-v) <n>]
+		   [--previous-count=<n>]
 		   [--to=<email>] [--cc=<email>]
 		   [--[no-]cover-letter] [--quiet]
 		   [--[no-]encode-email-headers]
@@ -221,6 +222,15 @@ populated with placeholder text.
 	`--subject-prefix` option) has ` v<n>` appended to it.  E.g.
 	`--reroll-count=4` may produce `v4-0001-add-makefile.patch`
 	file that has "Subject: [PATCH v4 1/20] Add makefile" in it.
+	now can support non-integrated version number like `-v1.1`.
+
+--previous-count=<n>::
+	Under the premise that we have used `--reroll-count=<n>`,
+	we can use `--previous-count=<n>` to specify the previous
+	version number. E.g. When we use the `--range-diff` or
+	`--interdiff` option and combine with `-v2.3 --previous-count=2.2`,
+	"Interdiff against v2.2:" or "Range-diff against v2.2:"
+	will be output in the patch.
 
 --to=<email>::
 	Add a `To:` header to the email headers. This is in addition
diff --git a/builtin/log.c b/builtin/log.c
index f67b67d80ed1..95c95eab5393 100644
--- a/builtin/log.c
+++ b/builtin/log.c
@@ -1662,13 +1662,15 @@ static void print_bases(struct base_tree_info *bases, FILE *file)
 	oidclr(&bases->base_commit);
 }
 
-static const char *diff_title(struct strbuf *sb, int reroll_count,
-		       const char *generic, const char *rerolled)
+static const char *diff_title(struct strbuf *sb, const char *reroll_count, int reroll_count_is_integer,
+			const char*previous_count, const char *generic, const char *rerolled)
 {
-	if (reroll_count <= 0)
+	if (!reroll_count || (!reroll_count_is_integer && !previous_count))
 		strbuf_addstr(sb, generic);
-	else /* RFC may be v0, so allow -v1 to diff against v0 */
-		strbuf_addf(sb, rerolled, reroll_count - 1);
+	else if (reroll_count_is_integer)/* RFC may be v0, so allow -v1 to diff against v0 */
+		strbuf_addf(sb, rerolled, atoi(reroll_count) - 1);
+	else if (previous_count)
+		strbuf_addf(sb, rerolled, previous_count);
 	return sb->buf;
 }
 
@@ -1717,7 +1719,9 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix)
 	struct strbuf buf = STRBUF_INIT;
 	int use_patch_format = 0;
 	int quiet = 0;
-	int reroll_count = -1;
+	int reroll_count_is_integer = 0;
+	const char *reroll_count = NULL;
+	const char *previous_count = NULL;
 	char *cover_from_description_arg = NULL;
 	char *branch_name = NULL;
 	char *base_commit = NULL;
@@ -1751,8 +1755,10 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix)
 			    N_("use <sfx> instead of '.patch'")),
 		OPT_INTEGER(0, "start-number", &start_number,
 			    N_("start numbering patches at <n> instead of 1")),
-		OPT_INTEGER('v', "reroll-count", &reroll_count,
-			    N_("mark the series as Nth re-roll")),
+		OPT_STRING('v', "reroll-count", &reroll_count, N_("reroll-count"),
+			    N_("mark the series as specified version re-roll")),
+		OPT_STRING(0, "previous-count", &previous_count, N_("previous-count"),
+			    N_("specified as the last version while we use --reroll-count")),
 		OPT_INTEGER(0, "filename-max-length", &fmt_patch_name_max,
 			    N_("max length of output filename")),
 		OPT_CALLBACK_F(0, "rfc", &rev, NULL,
@@ -1861,10 +1867,20 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix)
 
 	if (cover_from_description_arg)
 		cover_from_description_mode = parse_cover_from_description(cover_from_description_arg);
-
-	if (0 < reroll_count) {
+	if (previous_count && !reroll_count)
+		usage(_("previous-count can only used when reroll-count is used"));
+	if (reroll_count) {
 		struct strbuf sprefix = STRBUF_INIT;
-		strbuf_addf(&sprefix, "%s v%d",
+		char ch;
+		size_t i = 0 , reroll_count_len = strlen(reroll_count);
+
+		for (; i != reroll_count_len; i++) {
+			ch = reroll_count[i];
+			if(!isdigit(ch))
+				break;
+		}
+		reroll_count_is_integer = i == reroll_count_len ? 1 : 0;
+		strbuf_addf(&sprefix, "%s v%s",
 			    rev.subject_prefix, reroll_count);
 		rev.reroll_count = reroll_count;
 		rev.subject_prefix = strbuf_detach(&sprefix, NULL);
@@ -2079,8 +2095,9 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix)
 		rev.idiff_oid1 = &idiff_prev.oid[idiff_prev.nr - 1];
 		rev.idiff_oid2 = get_commit_tree_oid(list[0]);
 		rev.idiff_title = diff_title(&idiff_title, reroll_count,
-					     _("Interdiff:"),
-					     _("Interdiff against v%d:"));
+			reroll_count_is_integer, previous_count, _("Interdiff:"),
+				reroll_count_is_integer ? _("Interdiff against v%d:") :
+					_("Interdiff against v%s:"));
 	}
 
 	if (creation_factor < 0)
@@ -2098,8 +2115,9 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix)
 		rev.rdiff2 = rdiff2.buf;
 		rev.creation_factor = creation_factor;
 		rev.rdiff_title = diff_title(&rdiff_title, reroll_count,
-					     _("Range-diff:"),
-					     _("Range-diff against v%d:"));
+			reroll_count_is_integer, previous_count, _("Range-diff:"),
+				reroll_count_is_integer ? _("Range-diff against v%d:") :
+					_("Range-diff against v%s:"));
 	}
 
 	if (!signature) {
diff --git a/log-tree.c b/log-tree.c
index 4531cebfab38..5f2e08ebcaab 100644
--- a/log-tree.c
+++ b/log-tree.c
@@ -369,8 +369,8 @@ void fmt_output_subject(struct strbuf *filename,
 	int start_len = filename->len;
 	int max_len = start_len + info->patch_name_max - (strlen(suffix) + 1);
 
-	if (0 < info->reroll_count)
-		strbuf_addf(filename, "v%d-", info->reroll_count);
+	if (info->reroll_count)
+		strbuf_addf(filename, "v%s-", info->reroll_count);
 	strbuf_addf(filename, "%04d-%s", nr, subject);
 
 	if (max_len < filename->len)
diff --git a/revision.h b/revision.h
index e6be3c845e66..097d08354c61 100644
--- a/revision.h
+++ b/revision.h
@@ -235,7 +235,7 @@ struct rev_info {
 	const char	*mime_boundary;
 	const char	*patch_suffix;
 	int		numbered_files;
-	int		reroll_count;
+	const char	*reroll_count;
 	char		*message_id;
 	struct ident_split from_ident;
 	struct string_list *ref_message_ids;
diff --git a/t/t3206-range-diff.sh b/t/t3206-range-diff.sh
index 1b26c4c2ef91..ffb91f27f75f 100755
--- a/t/t3206-range-diff.sh
+++ b/t/t3206-range-diff.sh
@@ -521,6 +521,22 @@ test_expect_success 'format-patch --range-diff as commentary' '
 	grep "> 1: .* new message" 0001-*
 '
 
+test_expect_success 'format-patch --range-diff reroll-count with a non-integer and previous-count ' '
+	git format-patch --range-diff=HEAD~1 -v2.9 --previous-count=2.8 HEAD~1 >actual &&
+	test_when_finished "rm v2.9-0001-*" &&
+	test_line_count = 1 actual &&
+	test_i18ngrep "^Range-diff ..* v2.8:$" v2.9-0001-* &&
+	grep "> 1: .* new message" v2.9-0001-*
+'
+
+test_expect_success 'format-patch --range-diff reroll-count with a integer previous-count' '
+	git format-patch --range-diff=HEAD~1 -v2 --previous-count=1.8 HEAD~1 >actual &&
+	test_when_finished "rm v2-0001-*" &&
+	test_line_count = 1 actual &&
+	test_i18ngrep "^Range-diff ..* v1:$" v2-0001-* &&
+	grep "> 1: .* new message" v2-0001-*
+'
+
 test_expect_success 'range-diff overrides diff.noprefix internally' '
 	git -c diff.noprefix=true range-diff HEAD^...
 '
diff --git a/t/t4014-format-patch.sh b/t/t4014-format-patch.sh
index 66630c8413d5..1b3c1dc273aa 100755
--- a/t/t4014-format-patch.sh
+++ b/t/t4014-format-patch.sh
@@ -378,6 +378,14 @@ test_expect_success 'reroll count' '
 	! grep -v "^Subject: \[PATCH v4 [0-3]/3\] " subjects
 '
 
+test_expect_success 'reroll count with a non-integer' '
+	rm -fr patches &&
+	git format-patch -o patches --cover-letter --reroll-count 4.4 main..side >list &&
+	! grep -v "^patches/v4.4-000[0-3]-" list &&
+	sed -n -e "/^Subject: /p" $(cat list) >subjects &&
+	! grep -v "^Subject: \[PATCH v4.4 [0-3]/3\] " subjects
+'
+
 test_expect_success 'reroll count (-v)' '
 	rm -fr patches &&
 	git format-patch -o patches --cover-letter -v4 main..side >list &&
@@ -386,6 +394,14 @@ test_expect_success 'reroll count (-v)' '
 	! grep -v "^Subject: \[PATCH v4 [0-3]/3\] " subjects
 '
 
+test_expect_success 'reroll count (-v) with a non-integer' '
+	rm -fr patches &&
+	git format-patch -o patches --cover-letter -v4.4 main..side >list &&
+	! grep -v "^patches/v4.4-000[0-3]-" list &&
+	sed -n -e "/^Subject: /p" $(cat list) >subjects &&
+	! grep -v "^Subject: \[PATCH v4.4 [0-3]/3\] " subjects
+'
+
 check_threading () {
 	expect="$1" &&
 	shift &&
@@ -2255,6 +2271,23 @@ test_expect_success 'interdiff: reroll-count' '
 	test_i18ngrep "^Interdiff ..* v1:$" v2-0000-cover-letter.patch
 '
 
+test_expect_success 'interdiff: reroll-count with a non-integer' '
+	git format-patch --cover-letter --interdiff=boop~2 -v2.2 -1 boop &&
+	test_i18ngrep "^Interdiff:$" v2.2-0000-cover-letter.patch
+'
+
+test_expect_success 'interdiff: reroll-count with a non-integer and previous-count ' '
+	git format-patch --cover-letter --interdiff=boop~2 -v2.2 --previous-count=2.1 -1 boop &&
+	test_i18ngrep "^Interdiff ..* v2.1:$" v2.2-0000-cover-letter.patch
+'
+
+test_expect_success 'interdiff: reroll-count with a integer and previous-count ' '
+	git format-patch --cover-letter --interdiff=boop~2 -v2 --previous-count=1.5 -1 boop &&
+	test_i18ngrep "^Interdiff ..* v1:$" v2-0000-cover-letter.patch
+'
+test_expect_success 'interdiff: previous-count without reroll-count ' '
+	test_must_fail git format-patch --cover-letter --interdiff=boop~2 --previous-count=1.5 -1 boop
+'
 test_expect_success 'interdiff: solo-patch' '
 	cat >expect <<-\EOF &&
 	  +fleep
