diff --git a/.llvm.metadata b/.llvm.metadata
new file mode 100644
index 0000000..987e347
--- /dev/null
+++ b/.llvm.metadata
@@ -0,0 +1,6 @@
+860a3605f08a0a56a8de4e073e26a259871623a6 llvm-17.0.6.src.tar.xz
+2ad479ab00a6d5e61ecb953997cfeef6650a687a llvm-17.0.6.src.tar.xz.sig
+4b397344260c934e687be7efa0f8456a9dd46f44 cmake-17.0.6.src.tar.xz
+fa31d348b6780478403484e22139d25f403503d4 cmake-17.0.6.src.tar.xz.sig
+a35dc22cd3d983a556f6e4a63c8dac6a84e01caf third-party-17.0.6.src.tar.xz
+12128cdab7414aeedd573c61cbc2fa82e75491db third-party-17.0.6.src.tar.xz.sig
diff --git a/0001-PEI-Don-t-zero-out-noreg-operands.patch b/0001-PEI-Don-t-zero-out-noreg-operands.patch
new file mode 100644
index 0000000..0f16465
--- /dev/null
+++ b/0001-PEI-Don-t-zero-out-noreg-operands.patch
@@ -0,0 +1,74 @@
+From 9d1f05a7b8537deb5f626cd1b7b26ef2678f4c8e Mon Sep 17 00:00:00 2001
+From: Arthur Eubanks <aeubanks@google.com>
+Date: Thu, 27 Jul 2023 13:27:58 -0700
+Subject: [PATCH] [PEI] Don't zero out noreg operands
+
+A tail call may have $noreg operands.
+
+Fixes a crash.
+
+Reviewed By: xgupta
+
+Differential Revision: https://reviews.llvm.org/D156485
+
+(cherry picked from commit f800c1f3b207e7bcdc8b4c7192928d9a078242a0)
+---
+ llvm/lib/CodeGen/PrologEpilogInserter.cpp    |  9 +++++++--
+ llvm/test/CodeGen/X86/zero-call-used-regs.ll | 14 ++++++++++++++
+ 2 files changed, 21 insertions(+), 2 deletions(-)
+
+diff --git a/llvm/lib/CodeGen/PrologEpilogInserter.cpp b/llvm/lib/CodeGen/PrologEpilogInserter.cpp
+index e323aaaeefaf..49047719fdaa 100644
+--- a/llvm/lib/CodeGen/PrologEpilogInserter.cpp
++++ b/llvm/lib/CodeGen/PrologEpilogInserter.cpp
+@@ -1285,6 +1285,8 @@ void PEI::insertZeroCallUsedRegs(MachineFunction &MF) {
+           continue;
+ 
+         MCRegister Reg = MO.getReg();
++        if (!Reg)
++          continue;
+ 
+         // This picks up sibling registers (e.q. %al -> %ah).
+         for (MCRegUnit Unit : TRI.regunits(Reg))
+@@ -1308,8 +1310,11 @@ void PEI::insertZeroCallUsedRegs(MachineFunction &MF) {
+         if (!MO.isReg())
+           continue;
+ 
+-        for (const MCPhysReg &Reg :
+-             TRI.sub_and_superregs_inclusive(MO.getReg()))
++        MCRegister Reg = MO.getReg();
++        if (!Reg)
++          continue;
++
++        for (const MCPhysReg Reg : TRI.sub_and_superregs_inclusive(Reg))
+           RegsToZero.reset(Reg);
+       }
+     }
+diff --git a/llvm/test/CodeGen/X86/zero-call-used-regs.ll b/llvm/test/CodeGen/X86/zero-call-used-regs.ll
+index 63d51c916bb9..97ad5ce9c8cb 100644
+--- a/llvm/test/CodeGen/X86/zero-call-used-regs.ll
++++ b/llvm/test/CodeGen/X86/zero-call-used-regs.ll
+@@ -241,6 +241,20 @@ entry:
+   ret i32 %x
+ }
+ 
++define dso_local void @tailcall(ptr %p) local_unnamed_addr #0 "zero-call-used-regs"="used-gpr" {
++; I386-LABEL: tailcall:
++; I386:       # %bb.0:
++; I386-NEXT:    movl {{[0-9]+}}(%esp), %eax
++; I386-NEXT:    jmpl *(%eax) # TAILCALL
++;
++; X86-64-LABEL: tailcall:
++; X86-64:       # %bb.0:
++; X86-64-NEXT:    jmpq *(%rdi) # TAILCALL
++  %c = load ptr, ptr %p
++  tail call void %c()
++  ret void
++}
++
+ ; Don't emit zeroing registers in "main" function.
+ define dso_local i32 @main() local_unnamed_addr #1 {
+ ; I386-LABEL: main:
+-- 
+2.43.0
+
diff --git a/llvm.spec b/llvm.spec
index d3e7bb5..8b89770 100644
--- a/llvm.spec
+++ b/llvm.spec
@@ -118,7 +118,7 @@
 
 Name:		%{pkg_name}
 Version:	%{maj_ver}.%{min_ver}.%{patch_ver}%{?rc_ver:~rc%{rc_ver}}%{?llvm_snapshot_version_suffix:~%{llvm_snapshot_version_suffix}}
-Release:	1%{?dist}
+Release:	2%{?dist}
 Summary:	The Low Level Virtual Machine
 
 License:	Apache-2.0 WITH LLVM-exception OR NCSA
@@ -138,6 +138,9 @@ Source5:	https://github.com/llvm/llvm-project/releases/download/llvmorg-%{maj_ve
 Source6:	release-keys.asc
 %endif
 
+# Backport of https://reviews.llvm.org/D156485 for RHEL-23865.
+Patch0: 0001-PEI-Don-t-zero-out-noreg-operands.patch
+
 # RHEL-specific patch to avoid unwanted recommonmark dep
 Patch101:	0101-Deactivate-markdown-doc.patch
 
@@ -652,6 +655,9 @@ fi
 %endif
 
 %changelog
+* Fri Feb 02 2024 Nikita Popov <npopov@redhat.com> - 17.0.6-2
+- Fix crash with -fzero-call-used-regs (RHEL-23865)
+
 * Wed Nov 29 2023 Nikita Popov <npopov@redhat.com> - 17.0.6-1
 - Update to LLVM 17.0.6