diff --git a/quilt.changes b/quilt.changes
index ff47a29..d6a9df3 100644
--- a/quilt.changes
+++ b/quilt.changes
@@ -1,3 +1,11 @@
+-------------------------------------------------------------------
+Thu Oct  6 16:57:34 UTC 2022 - Jean Delvare <jdelvare@suse.com>
+
+- setup-document-the-limitation-of-spec-file-support.patch:
+  Document the fact that "quilt setup" does not support arbitrary
+  %prep sections and some adjustments to the spec file may be
+  needed (boo#1203791).
+
 -------------------------------------------------------------------
 Fri Sep  9 08:18:31 UTC 2022 - Jean Delvare <jdelvare@suse.com>
 
diff --git a/quilt.spec b/quilt.spec
index 759d843..f0affa3 100644
--- a/quilt.spec
+++ b/quilt.spec
@@ -39,6 +39,7 @@ URL:            http://savannah.nongnu.org/projects/quilt
 Source:         %{name}-%{version}.tar.bz2
 Source1:        suse-start-quilt-mode.el
 Patch1:         avoid-warnings-with-grep-3.8.patch
+Patch2:         setup-document-the-limitation-of-spec-file-support.patch
 Patch81:        expand.diff
 Patch82:        quilt-support-vimdiff.patch
 Patch83:        test-faildiff-workaround-order-bug.patch
@@ -63,6 +64,7 @@ un-applied, refreshed, and more.
 %prep
 %setup -q
 %patch1 -p1
+%patch2 -p1
 %patch81 -p1
 %patch82 -p1
 %patch83 -p1
diff --git a/setup-document-the-limitation-of-spec-file-support.patch b/setup-document-the-limitation-of-spec-file-support.patch
new file mode 100644
index 0000000..3759189
--- /dev/null
+++ b/setup-document-the-limitation-of-spec-file-support.patch
@@ -0,0 +1,38 @@
+From: Jean Delvare <jdelvare@suse.de>
+Date: Thu, 6 Oct 2022 18:52:52 +0200
+Subject: setup: Document the limitation of spec file support
+Git-commit: b73e4afa7e4c28a981430c5b80a95254f2ed6b77
+Patch-mainline: yes
+References: boo#1203791
+
+Quilt setup can't be used on arbitrary spec files. Due to the fact
+that quilt only deals with patches, every other modification to the
+working tree has to happen first, and the patches must be applied
+last.
+
+This is a design limitation and not a bug, but document it so that
+the users are aware of it and can adjust the %prep section of their
+spec file if needed.
+
+Signed-off-by: Jean Delvare <jdelvare@suse.de>
+---
+ quilt/setup.in |    8 +++++++-
+ 1 file changed, 7 insertions(+), 1 deletion(-)
+
+--- a/quilt/setup.in
++++ b/quilt/setup.in
+@@ -279,7 +279,13 @@ Initializes a source tree from an rpm sp
+ 
+ --fast	Use the new, faster method to process the spec file. In this mode,
+ 	rpmbuild is told to generate a working tree directly in the target
+-	directory. This is now the default.
++	directory. This is the default (since quilt version 0.67).
++
++The setup command is only guaranteed to work properly on spec files where
++applying all the patches is the last thing done in the %%prep section. This is
++a design limitation due to the fact that quilt can only operate on patches. If
++other commands in the %%prep section modify the patched files, this must
++happen first, otherwise you won't be able to push the patch series.
+ "
+ 		exit 0
+ 	else