diff --git a/doc/conf.py b/doc/conf.py
index eb74b86aefbab632dc42d4781b40b997953a40c3..dae62319072e88a17fbb0440bc01ccea4e04fa95 100644
--- a/doc/conf.py
+++ b/doc/conf.py
@@ -31,7 +31,7 @@ from load_config import loadConfig
 # -- General configuration ------------------------------------------------
 
 # If your documentation needs a minimal Sphinx version, state it here.
-needs_sphinx = '1.3'
+needs_sphinx = '2.4.4'
 
 # Add any Sphinx extension module names here, as strings. They can be
 # extensions coming with Sphinx (named 'sphinx.ext.*') or your custom
@@ -118,19 +118,12 @@ if major >= 3:
 
 else:
     extensions.append('cdomain')
-    if major == 1 and minor < 7:
-        sys.stderr.write('WARNING: Sphinx 1.7 or greater will be required as of '
-                         'the v2021.04 release\n')
 
 # Ensure that autosectionlabel will produce unique names
 autosectionlabel_prefix_document = True
 autosectionlabel_maxdepth = 2
 
-# The name of the math extension changed on Sphinx 1.4
-if (major == 1 and minor > 3) or (major > 1):
-    extensions.append("sphinx.ext.imgmath")
-else:
-    extensions.append("sphinx.ext.pngmath")
+extensions.append("sphinx.ext.imgmath")
 
 # Add any paths that contain templates here, relative to this directory.
 templates_path = ['_templates']
@@ -380,72 +373,6 @@ if cjk_cmd.find("Noto Sans CJK SC") >= 0:
         \\setCJKmainfont{Noto Sans CJK SC}
      '''
 
-# Fix reference escape troubles with Sphinx 1.4.x
-if major == 1 and minor > 3:
-    latex_elements['preamble']  += '\\renewcommand*{\\DUrole}[2]{ #2 }\n'
-
-if major == 1 and minor <= 4:
-    latex_elements['preamble']  += '\\usepackage[margin=0.5in, top=1in, bottom=1in]{geometry}'
-elif major == 1 and (minor > 5 or (minor == 5 and patch >= 3)):
-    latex_elements['sphinxsetup'] = 'hmargin=0.5in, vmargin=1in'
-    latex_elements['preamble']  += '\\fvset{fontsize=auto}\n'
-
-# Customize notice background colors on Sphinx < 1.6:
-if major == 1 and minor < 6:
-   latex_elements['preamble']  += '''
-        \\usepackage{ifthen}
-
-        % Put notes in color and let them be inside a table
-	\\definecolor{NoteColor}{RGB}{204,255,255}
-	\\definecolor{WarningColor}{RGB}{255,204,204}
-	\\definecolor{AttentionColor}{RGB}{255,255,204}
-	\\definecolor{ImportantColor}{RGB}{192,255,204}
-	\\definecolor{OtherColor}{RGB}{204,204,204}
-        \\newlength{\\mynoticelength}
-        \\makeatletter\\newenvironment{coloredbox}[1]{%
-	   \\setlength{\\fboxrule}{1pt}
-	   \\setlength{\\fboxsep}{7pt}
-	   \\setlength{\\mynoticelength}{\\linewidth}
-	   \\addtolength{\\mynoticelength}{-2\\fboxsep}
-	   \\addtolength{\\mynoticelength}{-2\\fboxrule}
-           \\begin{lrbox}{\\@tempboxa}\\begin{minipage}{\\mynoticelength}}{\\end{minipage}\\end{lrbox}%
-	   \\ifthenelse%
-	      {\\equal{\\py@noticetype}{note}}%
-	      {\\colorbox{NoteColor}{\\usebox{\\@tempboxa}}}%
-	      {%
-	         \\ifthenelse%
-	         {\\equal{\\py@noticetype}{warning}}%
-	         {\\colorbox{WarningColor}{\\usebox{\\@tempboxa}}}%
-		 {%
-	            \\ifthenelse%
-	            {\\equal{\\py@noticetype}{attention}}%
-	            {\\colorbox{AttentionColor}{\\usebox{\\@tempboxa}}}%
-		    {%
-	               \\ifthenelse%
-	               {\\equal{\\py@noticetype}{important}}%
-	               {\\colorbox{ImportantColor}{\\usebox{\\@tempboxa}}}%
-	               {\\colorbox{OtherColor}{\\usebox{\\@tempboxa}}}%
-		    }%
-		 }%
-	      }%
-        }\\makeatother
-
-        \\makeatletter
-        \\renewenvironment{notice}[2]{%
-          \\def\\py@noticetype{#1}
-          \\begin{coloredbox}{#1}
-          \\bf\\it
-          \\par\\strong{#2}
-          \\csname py@noticestart@#1\\endcsname
-        }
-	{
-          \\csname py@noticeend@\\py@noticetype\\endcsname
-          \\end{coloredbox}
-        }
-	\\makeatother
-
-     '''
-
 # With Sphinx 1.6, it is possible to change the Bg color directly
 # by using:
 #	\definecolor{sphinxnoteBgColor}{RGB}{204,255,255}
diff --git a/doc/sphinx/kerneldoc.py b/doc/sphinx/kerneldoc.py
index e9857ab904f1858566f4d0f10e1eb6c73794dad3..8189c33b9ddafd540d38c58290d07ce9248a1b2a 100644
--- a/doc/sphinx/kerneldoc.py
+++ b/doc/sphinx/kerneldoc.py
@@ -37,18 +37,8 @@ import glob
 from docutils import nodes, statemachine
 from docutils.statemachine import ViewList
 from docutils.parsers.rst import directives, Directive
-
-#
-# AutodocReporter is only good up to Sphinx 1.7
-#
 import sphinx
-
-Use_SSI = sphinx.__version__[:3] >= '1.7'
-if Use_SSI:
-    from sphinx.util.docutils import switch_source_input
-else:
-    from sphinx.ext.autodoc import AutodocReporter
-
+from sphinx.util.docutils import switch_source_input
 import kernellog
 
 __version__  = '1.0'
@@ -163,18 +153,8 @@ class KernelDocDirective(Directive):
             return [nodes.error(None, nodes.paragraph(text = "kernel-doc missing"))]
 
     def do_parse(self, result, node):
-        if Use_SSI:
-            with switch_source_input(self.state, result):
-                self.state.nested_parse(result, 0, node, match_titles=1)
-        else:
-            save = self.state.memo.title_styles, self.state.memo.section_level, self.state.memo.reporter
-            self.state.memo.reporter = AutodocReporter(result, self.state.memo.reporter)
-            self.state.memo.title_styles, self.state.memo.section_level = [], 0
-            try:
-                self.state.nested_parse(result, 0, node, match_titles=1)
-            finally:
-                self.state.memo.title_styles, self.state.memo.section_level, self.state.memo.reporter = save
-
+        with switch_source_input(self.state, result):
+            self.state.nested_parse(result, 0, node, match_titles=1)
 
 def setup(app):
     app.add_config_value('kerneldoc_bin', None, 'env')