diff --git a/glibc-rh2026399.patch b/glibc-rh2026399.patch
new file mode 100644
index 0000000..05d3e40
--- /dev/null
+++ b/glibc-rh2026399.patch
@@ -0,0 +1,67 @@
+Emergency patch to disable EVEX-optimized strcmp.
+
+https://bugzilla.redhat.com/show_bug.cgi?id=2026399
+https://sourceware.org/bugzilla/show_bug.cgi?id=28646
+
+diff --git a/sysdeps/x86_64/multiarch/ifunc-memcmp.h b/sysdeps/x86_64/multiarch/ifunc-memcmp.h
+index 89e2129968e1e49c..47e6b64b67ad1685 100644
+--- a/sysdeps/x86_64/multiarch/ifunc-memcmp.h
++++ b/sysdeps/x86_64/multiarch/ifunc-memcmp.h
+@@ -36,10 +36,6 @@ IFUNC_SELECTOR (void)
+       && CPU_FEATURE_USABLE_P (cpu_features, BMI2)
+       && CPU_FEATURES_ARCH_P (cpu_features, AVX_Fast_Unaligned_Load))
+     {
+-      if (CPU_FEATURE_USABLE_P (cpu_features, AVX512VL)
+-	  && CPU_FEATURE_USABLE_P (cpu_features, AVX512BW))
+-	return OPTIMIZE (evex_movbe);
+-
+       if (CPU_FEATURE_USABLE_P (cpu_features, RTM))
+ 	return OPTIMIZE (avx2_movbe_rtm);
+ 
+diff --git a/sysdeps/x86_64/multiarch/ifunc-memcmpeq.h b/sysdeps/x86_64/multiarch/ifunc-memcmpeq.h
+index 2ea38adf05777281..1a2cff77c861bee8 100644
+--- a/sysdeps/x86_64/multiarch/ifunc-memcmpeq.h
++++ b/sysdeps/x86_64/multiarch/ifunc-memcmpeq.h
+@@ -33,10 +33,6 @@ IFUNC_SELECTOR (void)
+       && CPU_FEATURE_USABLE_P (cpu_features, BMI2)
+       && CPU_FEATURES_ARCH_P (cpu_features, AVX_Fast_Unaligned_Load))
+     {
+-      if (CPU_FEATURE_USABLE_P (cpu_features, AVX512VL)
+-	  && CPU_FEATURE_USABLE_P (cpu_features, AVX512BW))
+-	return OPTIMIZE1 (evex);
+-
+       if (CPU_FEATURE_USABLE_P (cpu_features, RTM))
+ 	return OPTIMIZE1 (avx2_rtm);
+ 
+diff --git a/sysdeps/x86_64/multiarch/strcmp.c b/sysdeps/x86_64/multiarch/strcmp.c
+index 7c2901bf44456259..7cdfce1d7a4f562e 100644
+--- a/sysdeps/x86_64/multiarch/strcmp.c
++++ b/sysdeps/x86_64/multiarch/strcmp.c
+@@ -41,11 +41,6 @@ IFUNC_SELECTOR (void)
+   if (CPU_FEATURE_USABLE_P (cpu_features, AVX2)
+       && CPU_FEATURES_ARCH_P (cpu_features, AVX_Fast_Unaligned_Load))
+     {
+-      if (CPU_FEATURE_USABLE_P (cpu_features, AVX512VL)
+-	  && CPU_FEATURE_USABLE_P (cpu_features, AVX512BW)
+-	  && CPU_FEATURE_USABLE_P (cpu_features, BMI2))
+-	return OPTIMIZE (evex);
+-
+       if (CPU_FEATURE_USABLE_P (cpu_features, RTM))
+ 	return OPTIMIZE (avx2_rtm);
+ 
+diff --git a/sysdeps/x86_64/multiarch/strncmp.c b/sysdeps/x86_64/multiarch/strncmp.c
+index f94a421784bfe923..c3e34def9fc8fb93 100644
+--- a/sysdeps/x86_64/multiarch/strncmp.c
++++ b/sysdeps/x86_64/multiarch/strncmp.c
+@@ -41,11 +41,6 @@ IFUNC_SELECTOR (void)
+   if (CPU_FEATURE_USABLE_P (cpu_features, AVX2)
+       && CPU_FEATURES_ARCH_P (cpu_features, AVX_Fast_Unaligned_Load))
+     {
+-      if (CPU_FEATURE_USABLE_P (cpu_features, AVX512VL)
+-	  && CPU_FEATURE_USABLE_P (cpu_features, AVX512BW)
+-	  && CPU_FEATURE_USABLE_P (cpu_features, BMI2))
+-	return OPTIMIZE (evex);
+-
+       if (CPU_FEATURE_USABLE_P (cpu_features, RTM))
+ 	return OPTIMIZE (avx2_rtm);
+ 
diff --git a/glibc.spec b/glibc.spec
index d3b9495..2e55266 100644
--- a/glibc.spec
+++ b/glibc.spec
@@ -151,7 +151,7 @@ end \
 Summary: The GNU libc libraries
 Name: glibc
 Version: %{glibcversion}
-Release: 23%{?dist}
+Release: 24%{?dist}
 
 # In general, GPLv2+ is used by programs, LGPLv2+ is used for
 # libraries.
@@ -230,6 +230,7 @@ Patch29: glibc-fedora-nsswitch.patch
 Patch30: glibc-deprecated-selinux-makedb.patch
 Patch31: glibc-deprecated-selinux-nscd.patch
 Patch33: glibc-dso-sort-makefile-fail.patch
+Patch34: glibc-rh2026399.patch
 
 ##############################################################################
 # Continued list of core "glibc" package information:
@@ -2261,6 +2262,9 @@ fi
 %files -f compat-libpthread-nonshared.filelist -n compat-libpthread-nonshared
 
 %changelog
+* Fri Dec  3 2021 Florian Weimer <fweimer@redhat.com> - 2.34.9000-24
+- x86_64: Disable EVEX *cmp* string functions (#2026399)
+
 * Thu Dec  2 2021 Florian Weimer <fweimer@redhat.com> - 2.34.9000-23
 - Drop glibc-sdt-headers.patch; the official systemtap headers work again.