diff --git a/0001-tests-test-tar-info-Remove-bogus-test-requires-of-gu.patch b/0001-tests-test-tar-info-Remove-bogus-test-requires-of-gu.patch
index 3047bcf..680bfc8 100644
--- a/0001-tests-test-tar-info-Remove-bogus-test-requires-of-gu.patch
+++ b/0001-tests-test-tar-info-Remove-bogus-test-requires-of-gu.patch
@@ -1,7 +1,7 @@
 From d2e335b2d05e68c1fc7ed9b507fd5cafc172a112 Mon Sep 17 00:00:00 2001
 From: "Richard W.M. Jones" <rjones@redhat.com>
 Date: Tue, 13 Jun 2023 20:11:34 +0100
-Subject: [PATCH 01/15] tests/test-tar-info*: Remove bogus test requires of
+Subject: [PATCH 01/16] tests/test-tar-info*: Remove bogus test requires of
  guestfish
 
 These tests don't need guestfish so don't test for it.
diff --git a/0002-tar-Document-the-optional-tar-option-in-help-output-.patch b/0002-tar-Document-the-optional-tar-option-in-help-output-.patch
index 84be7bc..f1b4059 100644
--- a/0002-tar-Document-the-optional-tar-option-in-help-output-.patch
+++ b/0002-tar-Document-the-optional-tar-option-in-help-output-.patch
@@ -1,7 +1,7 @@
 From eb44ca26a84c369a7908f19517c0a2f8f621d57f Mon Sep 17 00:00:00 2001
 From: "Richard W.M. Jones" <rjones@redhat.com>
 Date: Tue, 13 Jun 2023 20:25:40 +0100
-Subject: [PATCH 02/15] tar: Document the optional tar option in --help output
+Subject: [PATCH 02/16] tar: Document the optional tar option in --help output
  and synopsis
 
 Fixes: commit 05b49f89dccb0ca3fd0919e9502c54dbcadf0b73
diff --git a/0003-tar-Implement-tar-limit.patch b/0003-tar-Implement-tar-limit.patch
index cd54c95..be8003c 100644
--- a/0003-tar-Implement-tar-limit.patch
+++ b/0003-tar-Implement-tar-limit.patch
@@ -1,7 +1,7 @@
 From ae3fb4def811f5bc42563128e8fae0a4288584d1 Mon Sep 17 00:00:00 2001
 From: "Richard W.M. Jones" <rjones@redhat.com>
 Date: Tue, 13 Jun 2023 20:01:05 +0100
-Subject: [PATCH 03/15] tar: Implement tar-limit
+Subject: [PATCH 03/16] tar: Implement tar-limit
 
 This can be used to ensure that the tar filter does not read
 indefinite amounts of input when opening the tar file.
diff --git a/0004-xz-Fix-error-message-to-refer-to-xz-max-block-parame.patch b/0004-xz-Fix-error-message-to-refer-to-xz-max-block-parame.patch
index ed32847..cf99a97 100644
--- a/0004-xz-Fix-error-message-to-refer-to-xz-max-block-parame.patch
+++ b/0004-xz-Fix-error-message-to-refer-to-xz-max-block-parame.patch
@@ -1,7 +1,7 @@
 From 35db543e38293808e910b291ff26b17284640ec9 Mon Sep 17 00:00:00 2001
 From: "Richard W.M. Jones" <rjones@redhat.com>
 Date: Mon, 19 Jun 2023 13:53:09 +0100
-Subject: [PATCH 04/15] xz: Fix error message to refer to xz-max-block
+Subject: [PATCH 04/16] xz: Fix error message to refer to xz-max-block
  parameter
 
 In the original xz plugin the parameter was called "maxblock", but
diff --git a/0005-configure-Recommend-using-g-with-OCAMLOPTFLAGS.patch b/0005-configure-Recommend-using-g-with-OCAMLOPTFLAGS.patch
index 6d419b0..ec9999d 100644
--- a/0005-configure-Recommend-using-g-with-OCAMLOPTFLAGS.patch
+++ b/0005-configure-Recommend-using-g-with-OCAMLOPTFLAGS.patch
@@ -1,7 +1,7 @@
 From 4398b1871f8832109fcdbe25c70a1dd341ed5bd4 Mon Sep 17 00:00:00 2001
 From: "Richard W.M. Jones" <rjones@redhat.com>
 Date: Wed, 21 Jun 2023 13:05:22 +0100
-Subject: [PATCH 05/15] configure: Recommend using -g with OCAMLOPTFLAGS
+Subject: [PATCH 05/16] configure: Recommend using -g with OCAMLOPTFLAGS
 
 ---
  configure.ac | 4 ++--
diff --git a/0006-tests-test_ocaml_plugin.ml-Print-a-message-when-test.patch b/0006-tests-test_ocaml_plugin.ml-Print-a-message-when-test.patch
index 25fbbdb..5c75615 100644
--- a/0006-tests-test_ocaml_plugin.ml-Print-a-message-when-test.patch
+++ b/0006-tests-test_ocaml_plugin.ml-Print-a-message-when-test.patch
@@ -1,7 +1,7 @@
 From b53b78e542fe8e49ce5c670e8ddc9d2be66f73cc Mon Sep 17 00:00:00 2001
 From: "Richard W.M. Jones" <rjones@redhat.com>
 Date: Wed, 21 Jun 2023 18:47:40 +0100
-Subject: [PATCH 06/15] tests/test_ocaml_plugin.ml: Print a message when test
+Subject: [PATCH 06/16] tests/test_ocaml_plugin.ml: Print a message when test
  plugin initializes
 
 It's useful to have a message which is printed as the top level
diff --git a/0007-ocaml-Add-I-unix-before-using-unix.cmxa.patch b/0007-ocaml-Add-I-unix-before-using-unix.cmxa.patch
index cb40bc2..049cfb4 100644
--- a/0007-ocaml-Add-I-unix-before-using-unix.cmxa.patch
+++ b/0007-ocaml-Add-I-unix-before-using-unix.cmxa.patch
@@ -1,7 +1,7 @@
 From b778c56443e11817d4974dcab5356e2d4065980b Mon Sep 17 00:00:00 2001
 From: "Richard W.M. Jones" <rjones@redhat.com>
 Date: Wed, 21 Jun 2023 18:56:58 +0100
-Subject: [PATCH 07/15] ocaml: Add -I +unix before using unix.cmxa
+Subject: [PATCH 07/16] ocaml: Add -I +unix before using unix.cmxa
 
 In OCaml 5.0 you will see this warning:
 
diff --git a/0008-ocaml-Replace-caml_leave_blocking_section-with-caml_.patch b/0008-ocaml-Replace-caml_leave_blocking_section-with-caml_.patch
index f7ba249..cb00591 100644
--- a/0008-ocaml-Replace-caml_leave_blocking_section-with-caml_.patch
+++ b/0008-ocaml-Replace-caml_leave_blocking_section-with-caml_.patch
@@ -1,7 +1,7 @@
 From f8b761c62f177176dfe154a95824576eef740827 Mon Sep 17 00:00:00 2001
 From: "Richard W.M. Jones" <rjones@redhat.com>
 Date: Wed, 21 Jun 2023 19:07:00 +0100
-Subject: [PATCH 08/15] ocaml: Replace caml_leave_blocking_section with
+Subject: [PATCH 08/16] ocaml: Replace caml_leave_blocking_section with
  caml_acquire_runtime_system
 
 Replace:
diff --git a/0009-ocaml-Always-unregister-the-global-root-and-free-the.patch b/0009-ocaml-Always-unregister-the-global-root-and-free-the.patch
index 2380388..acb9bc5 100644
--- a/0009-ocaml-Always-unregister-the-global-root-and-free-the.patch
+++ b/0009-ocaml-Always-unregister-the-global-root-and-free-the.patch
@@ -1,7 +1,7 @@
 From f4d5f179c9be6db3c39bc0752e36f262c3f87716 Mon Sep 17 00:00:00 2001
 From: "Richard W.M. Jones" <rjones@redhat.com>
 Date: Wed, 21 Jun 2023 20:15:46 +0100
-Subject: [PATCH 09/15] ocaml: Always unregister the global root and free the
+Subject: [PATCH 09/16] ocaml: Always unregister the global root and free the
  handle
 
 If the OCaml code did not provide a close method, we would never call
diff --git a/0010-ocaml-Fix-thread-registration-for-OCaml-5.patch b/0010-ocaml-Fix-thread-registration-for-OCaml-5.patch
index 05982d0..ebf111c 100644
--- a/0010-ocaml-Fix-thread-registration-for-OCaml-5.patch
+++ b/0010-ocaml-Fix-thread-registration-for-OCaml-5.patch
@@ -1,7 +1,7 @@
 From 9d4b87e0338d45456c0506fd2c25b80f7ef6b1e1 Mon Sep 17 00:00:00 2001
 From: "Richard W.M. Jones" <rjones@redhat.com>
 Date: Wed, 21 Jun 2023 20:18:58 +0100
-Subject: [PATCH 10/15] ocaml: Fix thread registration for OCaml 5
+Subject: [PATCH 10/16] ocaml: Fix thread registration for OCaml 5
 
 OCaml 5 is strict about registering threads before calling OCaml heap
 functions, and will abort the program with this error if you don't do
diff --git a/0011-tests-test-cc-ocaml.sh-Use-nbdkit-v-option-to-help-w.patch b/0011-tests-test-cc-ocaml.sh-Use-nbdkit-v-option-to-help-w.patch
index fc8045c..47186fb 100644
--- a/0011-tests-test-cc-ocaml.sh-Use-nbdkit-v-option-to-help-w.patch
+++ b/0011-tests-test-cc-ocaml.sh-Use-nbdkit-v-option-to-help-w.patch
@@ -1,7 +1,7 @@
 From c78266258709e2cbe6f0e869c866d09ad72c072c Mon Sep 17 00:00:00 2001
 From: "Richard W.M. Jones" <rjones@redhat.com>
 Date: Thu, 22 Jun 2023 10:33:31 +0100
-Subject: [PATCH 11/15] tests/test-cc-ocaml.sh: Use nbdkit -v option to help
+Subject: [PATCH 11/16] tests/test-cc-ocaml.sh: Use nbdkit -v option to help
  with debugging
 
 ---
diff --git a/0012-tests-Replace-SRCDIR-with-abs_top_srcdir.patch b/0012-tests-Replace-SRCDIR-with-abs_top_srcdir.patch
index 991b3a7..2d783f0 100644
--- a/0012-tests-Replace-SRCDIR-with-abs_top_srcdir.patch
+++ b/0012-tests-Replace-SRCDIR-with-abs_top_srcdir.patch
@@ -1,7 +1,7 @@
 From d968c4858847388e515bc1ef84ff4479c18a414d Mon Sep 17 00:00:00 2001
 From: "Richard W.M. Jones" <rjones@redhat.com>
 Date: Thu, 22 Jun 2023 10:44:10 +0100
-Subject: [PATCH 12/15] tests: Replace $SRCDIR with $abs_top_srcdir
+Subject: [PATCH 12/16] tests: Replace $SRCDIR with $abs_top_srcdir
 
 functions.sh defines $abs_top_srcdir so there's no need to use $SRCDIR
 in any test scripts.
diff --git a/0013-tests-test-read-password-Remove-use-of-SRCDIR.patch b/0013-tests-test-read-password-Remove-use-of-SRCDIR.patch
index 6ef088e..0d14568 100644
--- a/0013-tests-test-read-password-Remove-use-of-SRCDIR.patch
+++ b/0013-tests-test-read-password-Remove-use-of-SRCDIR.patch
@@ -1,7 +1,7 @@
 From 92ae65f93d8ebeb09500552d7ebfc1e8149ded6f Mon Sep 17 00:00:00 2001
 From: "Richard W.M. Jones" <rjones@redhat.com>
 Date: Thu, 22 Jun 2023 10:48:51 +0100
-Subject: [PATCH 13/15] tests/test-read-password*: Remove use of $SRCDIR
+Subject: [PATCH 13/16] tests/test-read-password*: Remove use of $SRCDIR
 
 These tests required exporting $abs_top_srcdir so that the plugin
 (which is a C script) can use it.
diff --git a/0014-tests-Stop-setting-SRCDIR-for-tests.patch b/0014-tests-Stop-setting-SRCDIR-for-tests.patch
index d61725d..2ff84a2 100644
--- a/0014-tests-Stop-setting-SRCDIR-for-tests.patch
+++ b/0014-tests-Stop-setting-SRCDIR-for-tests.patch
@@ -1,7 +1,7 @@
 From 2e3dcb2a720e4258b54d04ffd081c5159783df8e Mon Sep 17 00:00:00 2001
 From: "Richard W.M. Jones" <rjones@redhat.com>
 Date: Thu, 22 Jun 2023 10:50:17 +0100
-Subject: [PATCH 14/15] tests: Stop setting $SRCDIR for tests
+Subject: [PATCH 14/16] tests: Stop setting $SRCDIR for tests
 
 Since no tests use this variable any longer we can stop setting it.
 
diff --git a/0015-tests-Explicitly-add-L.-plugins-ocaml-.libs-to-find-.patch b/0015-tests-Explicitly-add-L.-plugins-ocaml-.libs-to-find-.patch
index ca09a13..e1b9e45 100644
--- a/0015-tests-Explicitly-add-L.-plugins-ocaml-.libs-to-find-.patch
+++ b/0015-tests-Explicitly-add-L.-plugins-ocaml-.libs-to-find-.patch
@@ -1,7 +1,7 @@
 From 3e4c1b79a72970c17cb42b21070e61ec634a38bb Mon Sep 17 00:00:00 2001
 From: "Richard W.M. Jones" <rjones@redhat.com>
 Date: Thu, 22 Jun 2023 11:15:27 +0100
-Subject: [PATCH 15/15] tests: Explicitly add -L../plugins/ocaml/.libs to find
+Subject: [PATCH 15/16] tests: Explicitly add -L../plugins/ocaml/.libs to find
  -lnbdkitocaml
 
 The actual libnbdkitocaml.so library is located in
diff --git a/0016-perl-Call-PERL_SET_CONTEXT-from-.open-method.patch b/0016-perl-Call-PERL_SET_CONTEXT-from-.open-method.patch
new file mode 100644
index 0000000..0a12e96
--- /dev/null
+++ b/0016-perl-Call-PERL_SET_CONTEXT-from-.open-method.patch
@@ -0,0 +1,39 @@
+From 495708e9d1b396ff450df15d5789b4f6c51f6ebc Mon Sep 17 00:00:00 2001
+From: "Richard W.M. Jones" <rjones@redhat.com>
+Date: Thu, 13 Jul 2023 11:50:02 +0100
+Subject: [PATCH 16/16] perl: Call PERL_SET_CONTEXT from .open method
+
+This appears to be necessary with Perl 5.38.
+---
+ plugins/perl/perl.c | 15 +++++++++++++++
+ 1 file changed, 15 insertions(+)
+
+diff --git a/plugins/perl/perl.c b/plugins/perl/perl.c
+index d3b7cede2..1d8d0c2b4 100644
+--- a/plugins/perl/perl.c
++++ b/plugins/perl/perl.c
+@@ -339,6 +339,21 @@ perl_open (int readonly)
+   SV *sv;
+   dSP;
+ 
++  /*
++   * From perlembed(1):
++   *
++   * "PERL_SET_CONTEXT(interp) should also be called whenever "interp"
++   * is used by a thread that did not create it (using either
++   * perl_alloc(), or the more esoteric perl_clone())."
++   *
++   * Since we may be called here from a new thread created within
++   * nbdkit, do this.  This is necessary since Perl 5.38.  It didn't
++   * seem to make a difference with earlier Perl, but doesn't break
++   * them either.
++   */
++
++  PERL_SET_CONTEXT (my_perl);
++
+   /* We check in perl_config that this callback is defined. */
+   ENTER;
+   SAVETMPS;
+-- 
+2.41.0
+
diff --git a/nbdkit.spec b/nbdkit.spec
index 5a11bfa..f916994 100644
--- a/nbdkit.spec
+++ b/nbdkit.spec
@@ -95,6 +95,7 @@ Patch:          0012-tests-Replace-SRCDIR-with-abs_top_srcdir.patch
 Patch:          0013-tests-test-read-password-Remove-use-of-SRCDIR.patch
 Patch:          0014-tests-Stop-setting-SRCDIR-for-tests.patch
 Patch:          0015-tests-Explicitly-add-L.-plugins-ocaml-.libs-to-find-.patch
+Patch:          0016-perl-Call-PERL_SET_CONTEXT-from-.open-method.patch
 
 BuildRequires: make
 %if 0%{patches_touch_autotools}