[PATCH 0/4] i386: Remove remaining CET bits

[PATCH 0/4] i386: Remove remaining CET bits

[H.J. Lu]

1. Add sysdeps/i386/libc-start.h and move x86-64 shadow stack startup
codes to sysdeps/x86_64/libc-start.h.
2. Move dl-cet.[ch] to x86_64 directories.
3. Move check-cet.awk to x86_64.
4. i386: Remove CET support bits.

H.J. Lu (4):
  x86: Move x86-64 shadow stack startup codes
  x86-64/cet: Move dl-cet.[ch] to x86_64 directories
  x86-64/cet: Move check-cet.awk to x86_64
  i386: Remove CET support bits

 sysdeps/i386/dl-machine.h                     | 11 +--
 sysdeps/i386/dl-trampoline.S                  | 69 -------------------
 sysdeps/i386/libc-start.h                     | 25 +++++++
 sysdeps/unix/sysv/linux/x86/dl-cet.h          | 63 -----------------
 sysdeps/unix/sysv/linux/x86_64/dl-cet.h       | 49 ++++++++++++-
 sysdeps/x86/cpu-features-offsets.sym          |  2 -
 sysdeps/x86/cpu-features.c                    |  4 +-
 sysdeps/x86/ldsodefs.h                        |  1 -
 sysdeps/x86_64/Makefile                       |  4 +-
 sysdeps/{x86 => x86_64}/check-cet.awk         |  0
 sysdeps/{x86 => x86_64}/dl-cet.c              |  0
 sysdeps/{x86 => x86_64}/dl-procruntime.c      |  2 +-
 sysdeps/x86_64/dl-trampoline.S                |  1 +
 .../feature-control.h}                        |  0
 sysdeps/x86_64/features-offsets.sym           |  6 ++
 sysdeps/x86_64/ldsodefs.h                     | 26 +++++++
 sysdeps/{x86 => x86_64}/libc-start.h          |  2 +-
 17 files changed, 114 insertions(+), 151 deletions(-)
 create mode 100644 sysdeps/i386/libc-start.h
 delete mode 100644 sysdeps/unix/sysv/linux/x86/dl-cet.h
 rename sysdeps/{x86 => x86_64}/check-cet.awk (100%)
 rename sysdeps/{x86 => x86_64}/dl-cet.c (100%)
 rename sysdeps/{x86 => x86_64}/dl-procruntime.c (97%)
 rename sysdeps/{x86/cet-control.h => x86_64/feature-control.h} (100%)
 create mode 100644 sysdeps/x86_64/features-offsets.sym
 create mode 100644 sysdeps/x86_64/ldsodefs.h
 rename sysdeps/{x86 => x86_64}/libc-start.h (98%)

-- 
2.43.0

[PATCH 1/4] x86: Move x86-64 shadow stack startup codes

[H.J. Lu]

Add sysdeps/i386/libc-start.h and move x86-64 shadow stack startup codes
to sysdeps/x86_64/libc-start.h
---
 sysdeps/i386/libc-start.h            | 25 +++++++++++++++++++++++++
 sysdeps/{x86 => x86_64}/libc-start.h |  2 +-
 2 files changed, 26 insertions(+), 1 deletion(-)
 create mode 100644 sysdeps/i386/libc-start.h
 rename sysdeps/{x86 => x86_64}/libc-start.h (98%)

diff --git a/sysdeps/i386/libc-start.h b/sysdeps/i386/libc-start.h
new file mode 100644
index 0000000000..c9b7d3614e
--- /dev/null
+++ b/sysdeps/i386/libc-start.h
@@ -0,0 +1,25 @@
+/* i386 definitions for libc main startup.
+   Copyright (C) 2018-2024 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#ifndef SHARED
+# define ARCH_SETUP_IREL() apply_irel ()
+# define ARCH_APPLY_IREL()
+# ifndef ARCH_SETUP_TLS
+#  define ARCH_SETUP_TLS() __libc_setup_tls ()
+# endif
+#endif /* !SHARED */
diff --git a/sysdeps/x86/libc-start.h b/sysdeps/x86_64/libc-start.h
similarity index 98%
rename from sysdeps/x86/libc-start.h
rename to sysdeps/x86_64/libc-start.h
index c3cc05888d..63fef17029 100644
--- a/sysdeps/x86/libc-start.h
+++ b/sysdeps/x86_64/libc-start.h
@@ -1,4 +1,4 @@
-/* X86 definitions for libc main startup.
+/* x86-64 definitions for libc main startup.
    Copyright (C) 2018-2024 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
-- 
2.43.0

[PATCH 2/4] x86-64/cet: Move dl-cet.[ch] to x86_64 directories

[H.J. Lu]

Since CET is only enabled for x86-64, move dl-cet.[ch] to x86_64
directories.
---
 sysdeps/unix/sysv/linux/x86/dl-cet.h    | 63 -------------------------
 sysdeps/unix/sysv/linux/x86_64/dl-cet.h | 47 +++++++++++++++++-
 sysdeps/{x86 => x86_64}/dl-cet.c        |  0
 3 files changed, 46 insertions(+), 64 deletions(-)
 delete mode 100644 sysdeps/unix/sysv/linux/x86/dl-cet.h
 rename sysdeps/{x86 => x86_64}/dl-cet.c (100%)

diff --git a/sysdeps/unix/sysv/linux/x86/dl-cet.h b/sysdeps/unix/sysv/linux/x86/dl-cet.h
deleted file mode 100644
index c10773ab0e..0000000000
--- a/sysdeps/unix/sysv/linux/x86/dl-cet.h
+++ /dev/null
@@ -1,63 +0,0 @@
-/* Linux/x86 CET initializers function.
-   Copyright (C) 2018-2024 Free Software Foundation, Inc.
-
-   The GNU C Library is free software; you can redistribute it and/or
-   modify it under the terms of the GNU Lesser General Public
-   License as published by the Free Software Foundation; either
-   version 2.1 of the License, or (at your option) any later version.
-
-   The GNU C Library is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-   Lesser General Public License for more details.
-
-   You should have received a copy of the GNU Lesser General Public
-   License along with the GNU C Library; if not, see
-   <https://www.gnu.org/licenses/>.  */
-
-#include <sys/prctl.h>
-#include <asm/prctl.h>
-
-static __always_inline int
-dl_cet_disable_cet (unsigned int cet_feature)
-{
-  if (cet_feature != GNU_PROPERTY_X86_FEATURE_1_SHSTK)
-    return -1;
-  long long int kernel_feature = ARCH_SHSTK_SHSTK;
-  return (int) INTERNAL_SYSCALL_CALL (arch_prctl, ARCH_SHSTK_DISABLE,
-				      kernel_feature);
-}
-
-static __always_inline int
-dl_cet_lock_cet (unsigned int cet_feature)
-{
-  if (cet_feature != GNU_PROPERTY_X86_FEATURE_1_SHSTK)
-    return -1;
-  /* Lock all SHSTK features.  */
-  long long int kernel_feature = -1;
-  return (int) INTERNAL_SYSCALL_CALL (arch_prctl, ARCH_SHSTK_LOCK,
-				      kernel_feature);
-}
-
-static __always_inline unsigned int
-dl_cet_get_cet_status (void)
-{
-  unsigned long long kernel_feature;
-  unsigned int status = 0;
-  if (INTERNAL_SYSCALL_CALL (arch_prctl, ARCH_SHSTK_STATUS,
-			     &kernel_feature) == 0)
-    {
-      if ((kernel_feature & ARCH_SHSTK_SHSTK) != 0)
-	status = GNU_PROPERTY_X86_FEATURE_1_SHSTK;
-    }
-  return status;
-}
-
-/* Enable shadow stack with a macro to avoid shadow stack underflow.  */
-#define ENABLE_X86_CET(cet_feature)				\
-  if ((cet_feature & GNU_PROPERTY_X86_FEATURE_1_SHSTK))		\
-    {								\
-      long long int kernel_feature = ARCH_SHSTK_SHSTK;		\
-      INTERNAL_SYSCALL_CALL (arch_prctl, ARCH_SHSTK_ENABLE,	\
-			     kernel_feature);			\
-    }
diff --git a/sysdeps/unix/sysv/linux/x86_64/dl-cet.h b/sysdeps/unix/sysv/linux/x86_64/dl-cet.h
index c89dd6bd42..94e9b9aa86 100644
--- a/sysdeps/unix/sysv/linux/x86_64/dl-cet.h
+++ b/sysdeps/unix/sysv/linux/x86_64/dl-cet.h
@@ -15,8 +15,53 @@
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
+#include <sys/prctl.h>
+#include <asm/prctl.h>
 #include <cpu-features-offsets.h>
-#include_next <dl-cet.h>
+
+static __always_inline int
+dl_cet_disable_cet (unsigned int cet_feature)
+{
+  if (cet_feature != GNU_PROPERTY_X86_FEATURE_1_SHSTK)
+    return -1;
+  long long int kernel_feature = ARCH_SHSTK_SHSTK;
+  return (int) INTERNAL_SYSCALL_CALL (arch_prctl, ARCH_SHSTK_DISABLE,
+				      kernel_feature);
+}
+
+static __always_inline int
+dl_cet_lock_cet (unsigned int cet_feature)
+{
+  if (cet_feature != GNU_PROPERTY_X86_FEATURE_1_SHSTK)
+    return -1;
+  /* Lock all SHSTK features.  */
+  long long int kernel_feature = -1;
+  return (int) INTERNAL_SYSCALL_CALL (arch_prctl, ARCH_SHSTK_LOCK,
+				      kernel_feature);
+}
+
+static __always_inline unsigned int
+dl_cet_get_cet_status (void)
+{
+  unsigned long long kernel_feature;
+  unsigned int status = 0;
+  if (INTERNAL_SYSCALL_CALL (arch_prctl, ARCH_SHSTK_STATUS,
+			     &kernel_feature) == 0)
+    {
+      if ((kernel_feature & ARCH_SHSTK_SHSTK) != 0)
+	status = GNU_PROPERTY_X86_FEATURE_1_SHSTK;
+    }
+  return status;
+}
+
+/* Enable shadow stack with a macro to avoid shadow stack underflow.  */
+#define ENABLE_X86_CET(cet_feature)				\
+  if ((cet_feature & GNU_PROPERTY_X86_FEATURE_1_SHSTK))		\
+    {								\
+      long long int kernel_feature = ARCH_SHSTK_SHSTK;		\
+      INTERNAL_SYSCALL_CALL (arch_prctl, ARCH_SHSTK_ENABLE,	\
+			     kernel_feature);			\
+    }
 
 #define X86_STRINGIFY_1(x)	#x
 #define X86_STRINGIFY(x)	X86_STRINGIFY_1 (x)
diff --git a/sysdeps/x86/dl-cet.c b/sysdeps/x86_64/dl-cet.c
similarity index 100%
rename from sysdeps/x86/dl-cet.c
rename to sysdeps/x86_64/dl-cet.c
-- 
2.43.0

[PATCH 3/4] x86-64/cet: Move check-cet.awk to x86_64

[H.J. Lu]

---
 sysdeps/x86_64/Makefile               | 2 +-
 sysdeps/{x86 => x86_64}/check-cet.awk | 0
 2 files changed, 1 insertion(+), 1 deletion(-)
 rename sysdeps/{x86 => x86_64}/check-cet.awk (100%)

diff --git a/sysdeps/x86_64/Makefile b/sysdeps/x86_64/Makefile
index 98f0e04f90..abb8b354af 100644
--- a/sysdeps/x86_64/Makefile
+++ b/sysdeps/x86_64/Makefile
@@ -468,7 +468,7 @@ $(cet-built-dso:=.note): %.note: %
 	mv -f $@T $@
 common-generated += $(cet-built-dso:$(common-objpfx)%=%.note)
 
-$(objpfx)check-cet.out: $(..)sysdeps/x86/check-cet.awk \
+$(objpfx)check-cet.out: $(..)/sysdeps/x86_64/check-cet.awk \
 			$(cet-built-dso:=.note)
 	LC_ALL=C $(AWK) -f $^ > $@; \
 	$(evaluate-test)
diff --git a/sysdeps/x86/check-cet.awk b/sysdeps/x86_64/check-cet.awk
similarity index 100%
rename from sysdeps/x86/check-cet.awk
rename to sysdeps/x86_64/check-cet.awk
-- 
2.43.0

[PATCH 4/4] i386: Remove CET support bits

[H.J. Lu]

1. Remove _dl_runtime_resolve_shstk and _dl_runtime_profile_shstk.
2. Move CET offsets from x86 cpu-features-offsets.sym to x86-64
features-offsets.sym.
3. Rename x86 cet-control.h to x86-64 feature-control.h since it is only
for x86-64 and also used for PLT rewrite.
4. Add x86-64 ldsodefs.h to include feature-control.h.
5. Change TUNABLE_CALLBACK (set_plt_rewrite) to x86-64 only.
6. Move x86 dl-procruntime.c to x86-64.
---
 sysdeps/i386/dl-machine.h                     | 11 +--
 sysdeps/i386/dl-trampoline.S                  | 69 -------------------
 sysdeps/unix/sysv/linux/x86_64/dl-cet.h       |  2 +-
 sysdeps/x86/cpu-features-offsets.sym          |  2 -
 sysdeps/x86/cpu-features.c                    |  4 +-
 sysdeps/x86/ldsodefs.h                        |  1 -
 sysdeps/x86_64/Makefile                       |  2 +-
 sysdeps/{x86 => x86_64}/dl-procruntime.c      |  2 +-
 sysdeps/x86_64/dl-trampoline.S                |  1 +
 .../feature-control.h}                        |  0
 sysdeps/x86_64/features-offsets.sym           |  6 ++
 sysdeps/x86_64/ldsodefs.h                     | 26 +++++++
 12 files changed, 41 insertions(+), 85 deletions(-)
 rename sysdeps/{x86 => x86_64}/dl-procruntime.c (97%)
 rename sysdeps/{x86/cet-control.h => x86_64/feature-control.h} (100%)
 create mode 100644 sysdeps/x86_64/features-offsets.sym
 create mode 100644 sysdeps/x86_64/ldsodefs.h

diff --git a/sysdeps/i386/dl-machine.h b/sysdeps/i386/dl-machine.h
index c69ae165ac..fc1ef96587 100644
--- a/sysdeps/i386/dl-machine.h
+++ b/sysdeps/i386/dl-machine.h
@@ -65,9 +65,6 @@ elf_machine_runtime_setup (struct link_map *l, struct r_scope_elem *scope[],
   extern void _dl_runtime_profile (Elf32_Word) attribute_hidden;
   extern void _dl_runtime_resolve_shstk (Elf32_Word) attribute_hidden;
   extern void _dl_runtime_profile_shstk (Elf32_Word) attribute_hidden;
-  /* Check if SHSTK is enabled by kernel.  */
-  bool shstk_enabled
-    = (GL(dl_x86_feature_1) & GNU_PROPERTY_X86_FEATURE_1_SHSTK) != 0;
 
   if (l->l_info[DT_JMPREL] && lazy)
     {
@@ -95,9 +92,7 @@ elf_machine_runtime_setup (struct link_map *l, struct r_scope_elem *scope[],
 #ifdef SHARED
       if (__glibc_unlikely (profile))
 	{
-	  got[2] = (shstk_enabled
-		    ? (Elf32_Addr) &_dl_runtime_profile_shstk
-		    : (Elf32_Addr) &_dl_runtime_profile);
+	  got[2] = (Elf32_Addr) &_dl_runtime_profile;
 
 	  if (GLRO(dl_profile) != NULL
 	      && _dl_name_match_p (GLRO(dl_profile), l))
@@ -109,9 +104,7 @@ elf_machine_runtime_setup (struct link_map *l, struct r_scope_elem *scope[],
 #endif
 	/* This function will get called to fix up the GOT entry indicated by
 	   the offset on the stack, and then jump to the resolved address.  */
-	got[2] = (shstk_enabled
-		  ? (Elf32_Addr) &_dl_runtime_resolve_shstk
-		  : (Elf32_Addr) &_dl_runtime_resolve);
+	got[2] = (Elf32_Addr) &_dl_runtime_resolve;
     }
 
   return lazy;
diff --git a/sysdeps/i386/dl-trampoline.S b/sysdeps/i386/dl-trampoline.S
index 2632020145..6c14d463b6 100644
--- a/sysdeps/i386/dl-trampoline.S
+++ b/sysdeps/i386/dl-trampoline.S
@@ -44,76 +44,7 @@ _dl_runtime_resolve:
 	cfi_endproc
 	.size _dl_runtime_resolve, .-_dl_runtime_resolve
 
-# The SHSTK compatible version.
-	.text
-	.globl _dl_runtime_resolve_shstk
-	.type _dl_runtime_resolve_shstk, @function
-	cfi_startproc
-	.align 16
-_dl_runtime_resolve_shstk:
-	cfi_adjust_cfa_offset (8)
-	pushl %eax		# Preserve registers otherwise clobbered.
-	cfi_adjust_cfa_offset (4)
-	pushl %edx
-	cfi_adjust_cfa_offset (4)
-	movl 12(%esp), %edx	# Copy args pushed by PLT in register.  Note
-	movl 8(%esp), %eax	# that `fixup' takes its parameters in regs.
-	call _dl_fixup		# Call resolver.
-	movl (%esp), %edx	# Get register content back.
-	movl %eax, %ecx		# Store the function address.
-	movl 4(%esp), %eax	# Get register content back.
-	addl $16, %esp		# Adjust stack: PLT1 + PLT2 + %eax + %edx
-	cfi_adjust_cfa_offset (-16)
-	jmp *%ecx		# Jump to function address.
-	cfi_endproc
-	.size _dl_runtime_resolve_shstk, .-_dl_runtime_resolve_shstk
-
 #if !defined PROF && defined SHARED
-# The SHSTK compatible version.
-	.globl _dl_runtime_profile_shstk
-	.type _dl_runtime_profile_shstk, @function
-	cfi_startproc
-	.align 16
-_dl_runtime_profile_shstk:
-	cfi_adjust_cfa_offset (8)
-	pushl %esp
-	cfi_adjust_cfa_offset (4)
-	addl $8, (%esp)		# Account for the pushed PLT data
-	pushl %ebp
-	cfi_adjust_cfa_offset (4)
-	pushl %eax		# Preserve registers otherwise clobbered.
-	cfi_adjust_cfa_offset (4)
-	pushl %ecx
-	cfi_adjust_cfa_offset (4)
-	pushl %edx
-	cfi_adjust_cfa_offset (4)
-	movl %esp, %ecx
-	subl $8, %esp
-	cfi_adjust_cfa_offset (8)
-	movl $-1, 4(%esp)
-	leal 4(%esp), %edx
-	movl %edx, (%esp)
-	pushl %ecx		# Address of the register structure
-	cfi_adjust_cfa_offset (4)
-	movl 40(%esp), %ecx	# Load return address
-	movl 36(%esp), %edx	# Copy args pushed by PLT in register.  Note
-	movl 32(%esp), %eax	# that `fixup' takes its parameters in regs.
-	call _dl_profile_fixup	# Call resolver.
-	cfi_adjust_cfa_offset (-8)
-	movl (%esp), %edx
-	testl %edx, %edx
-	jns 1f
-	movl 4(%esp), %edx	# Get register content back.
-	movl %eax, %ecx		# Store the function address.
-	movl 12(%esp), %eax	# Get register content back.
-	# Adjust stack: PLT1 + PLT2 + %esp + %ebp + %eax + %ecx + %edx
-	# + free.
-	addl $32, %esp
-	cfi_adjust_cfa_offset (-32)
-	jmp *%ecx		# Jump to function address.
-	cfi_endproc
-	.size _dl_runtime_profile_shstk, .-_dl_runtime_profile_shstk
-
 	.globl _dl_runtime_profile
 	.type _dl_runtime_profile, @function
 	cfi_startproc
diff --git a/sysdeps/unix/sysv/linux/x86_64/dl-cet.h b/sysdeps/unix/sysv/linux/x86_64/dl-cet.h
index 94e9b9aa86..a00c7ee662 100644
--- a/sysdeps/unix/sysv/linux/x86_64/dl-cet.h
+++ b/sysdeps/unix/sysv/linux/x86_64/dl-cet.h
@@ -17,7 +17,7 @@
 
 #include <sys/prctl.h>
 #include <asm/prctl.h>
-#include <cpu-features-offsets.h>
+#include <features-offsets.h>
 
 static __always_inline int
 dl_cet_disable_cet (unsigned int cet_feature)
diff --git a/sysdeps/x86/cpu-features-offsets.sym b/sysdeps/x86/cpu-features-offsets.sym
index 5429f60632..6a8fd29813 100644
--- a/sysdeps/x86/cpu-features-offsets.sym
+++ b/sysdeps/x86/cpu-features-offsets.sym
@@ -2,6 +2,4 @@
 
 #include <ldsodefs.h>
 
-RTLD_GLOBAL_RO_DL_X86_CPU_FEATURES_OFFSET offsetof (struct rtld_global_ro, _dl_x86_cpu_features)
 XSAVE_STATE_SIZE_OFFSET	offsetof (struct cpu_features, xsave_state_size)
-RTLD_GLOBAL_DL_X86_FEATURE_1_OFFSET offsetof (struct rtld_global, _dl_x86_feature_1)
diff --git a/sysdeps/x86/cpu-features.c b/sysdeps/x86/cpu-features.c
index 9ca307f521..46bdaffbc2 100644
--- a/sysdeps/x86/cpu-features.c
+++ b/sysdeps/x86/cpu-features.c
@@ -27,7 +27,7 @@
 extern void TUNABLE_CALLBACK (set_hwcaps) (tunable_val_t *)
   attribute_hidden;
 
-#ifdef SHARED
+#if defined SHARED && defined __x86_64__
 static void
 TUNABLE_CALLBACK (set_plt_rewrite) (tunable_val_t *valp)
 {
@@ -1125,8 +1125,10 @@ no_cpuid:
 #endif
 
 #ifdef SHARED
+# ifdef __x86_64__
   TUNABLE_GET (plt_rewrite, tunable_val_t *,
 	       TUNABLE_CALLBACK (set_plt_rewrite));
+# endif
 #else
   /* NB: In libc.a, call init_cacheinfo.  */
   init_cacheinfo ();
diff --git a/sysdeps/x86/ldsodefs.h b/sysdeps/x86/ldsodefs.h
index b2a6d71513..50dc81c022 100644
--- a/sysdeps/x86/ldsodefs.h
+++ b/sysdeps/x86/ldsodefs.h
@@ -61,7 +61,6 @@ struct La_x32_retval;
 				     struct La_x86_64_retval *,		\
 				     const char *)
 
-#include <cet-control.h>
 #include_next <ldsodefs.h>
 
 #endif
diff --git a/sysdeps/x86_64/Makefile b/sysdeps/x86_64/Makefile
index abb8b354af..10a253e4f1 100644
--- a/sysdeps/x86_64/Makefile
+++ b/sysdeps/x86_64/Makefile
@@ -10,7 +10,7 @@ LDFLAGS-rtld += -Wl,-z,nomark-plt
 endif
 
 ifeq ($(subdir),csu)
-gen-as-const-headers += link-defines.sym
+gen-as-const-headers += features-offsets.sym link-defines.sym
 endif
 
 ifeq ($(subdir),gmon)
diff --git a/sysdeps/x86/dl-procruntime.c b/sysdeps/x86_64/dl-procruntime.c
similarity index 97%
rename from sysdeps/x86/dl-procruntime.c
rename to sysdeps/x86_64/dl-procruntime.c
index 15b3d0d878..7078581778 100644
--- a/sysdeps/x86/dl-procruntime.c
+++ b/sysdeps/x86_64/dl-procruntime.c
@@ -1,4 +1,4 @@
-/* Data for processor runtime information.  x86 version.
+/* Data for processor runtime information.  x86-64 version.
    Copyright (C) 2018-2024 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
diff --git a/sysdeps/x86_64/dl-trampoline.S b/sysdeps/x86_64/dl-trampoline.S
index 4c1ba5c9af..b2e7e0f69b 100644
--- a/sysdeps/x86_64/dl-trampoline.S
+++ b/sysdeps/x86_64/dl-trampoline.S
@@ -19,6 +19,7 @@
 #include <config.h>
 #include <sysdep.h>
 #include <cpu-features-offsets.h>
+#include <features-offsets.h>
 #include <link-defines.h>
 #include <isa-level.h>
 
diff --git a/sysdeps/x86/cet-control.h b/sysdeps/x86_64/feature-control.h
similarity index 100%
rename from sysdeps/x86/cet-control.h
rename to sysdeps/x86_64/feature-control.h
diff --git a/sysdeps/x86_64/features-offsets.sym b/sysdeps/x86_64/features-offsets.sym
new file mode 100644
index 0000000000..9e4be3393a
--- /dev/null
+++ b/sysdeps/x86_64/features-offsets.sym
@@ -0,0 +1,6 @@
+#define SHARED 1
+
+#include <ldsodefs.h>
+
+RTLD_GLOBAL_RO_DL_X86_CPU_FEATURES_OFFSET offsetof (struct rtld_global_ro, _dl_x86_cpu_features)
+RTLD_GLOBAL_DL_X86_FEATURE_1_OFFSET offsetof (struct rtld_global, _dl_x86_feature_1)
diff --git a/sysdeps/x86_64/ldsodefs.h b/sysdeps/x86_64/ldsodefs.h
new file mode 100644
index 0000000000..0f468ddf5b
--- /dev/null
+++ b/sysdeps/x86_64/ldsodefs.h
@@ -0,0 +1,26 @@
+/* Run-time dynamic linker data structures for loaded ELF shared objects.
+   x86-64 version.
+   Copyright (C) 2024 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#ifndef	_X86_64_LDSODEFS_H
+#define	_X86_64_LDSODEFS_H	1
+
+#include <feature-control.h>
+#include_next <ldsodefs.h>
+
+#endif
-- 
2.43.0

Re: [PATCH 1/4] x86: Move x86-64 shadow stack startup codes

[Adhemerval Zanella Netto]

On 09/01/24 16:30, H.J. Lu wrote:
> Add sysdeps/i386/libc-start.h and move x86-64 shadow stack startup codes
> to sysdeps/x86_64/libc-start.h
> ---
>  sysdeps/i386/libc-start.h            | 25 +++++++++++++++++++++++++
>  sysdeps/{x86 => x86_64}/libc-start.h |  2 +-
>  2 files changed, 26 insertions(+), 1 deletion(-)
>  create mode 100644 sysdeps/i386/libc-start.h
>  rename sysdeps/{x86 => x86_64}/libc-start.h (98%)
> 
> diff --git a/sysdeps/i386/libc-start.h b/sysdeps/i386/libc-start.h
> new file mode 100644
> index 0000000000..c9b7d3614e
> --- /dev/null
> +++ b/sysdeps/i386/libc-start.h
> @@ -0,0 +1,25 @@
> +/* i386 definitions for libc main startup.
> +   Copyright (C) 2018-2024 Free Software Foundation, Inc.
> +   This file is part of the GNU C Library.
> +
> +   The GNU C Library is free software; you can redistribute it and/or
> +   modify it under the terms of the GNU Lesser General Public
> +   License as published by the Free Software Foundation; either
> +   version 2.1 of the License, or (at your option) any later version.
> +
> +   The GNU C Library is distributed in the hope that it will be useful,
> +   but WITHOUT ANY WARRANTY; without even the implied warranty of
> +   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> +   Lesser General Public License for more details.
> +
> +   You should have received a copy of the GNU Lesser General Public
> +   License along with the GNU C Library; if not, see
> +   <https://www.gnu.org/licenses/>.  */
> +
> +#ifndef SHARED
> +# define ARCH_SETUP_IREL() apply_irel ()
> +# define ARCH_APPLY_IREL()
> +# ifndef ARCH_SETUP_TLS
> +#  define ARCH_SETUP_TLS() __libc_setup_tls ()
> +# endif
> +#endif /* !SHARED */

I think you can just omit this file and use the generic one instead
(sysdeps/generic/libc-start.h).

> diff --git a/sysdeps/x86/libc-start.h b/sysdeps/x86_64/libc-start.h
> similarity index 98%
> rename from sysdeps/x86/libc-start.h
> rename to sysdeps/x86_64/libc-start.h
> index c3cc05888d..63fef17029 100644
> --- a/sysdeps/x86/libc-start.h
> +++ b/sysdeps/x86_64/libc-start.h
> @@ -1,4 +1,4 @@
> -/* X86 definitions for libc main startup.
> +/* x86-64 definitions for libc main startup.
>     Copyright (C) 2018-2024 Free Software Foundation, Inc.
>     This file is part of the GNU C Library.
>  

Ok.

Re: [PATCH 2/4] x86-64/cet: Move dl-cet.[ch] to x86_64 directories

[Adhemerval Zanella Netto]

On 09/01/24 16:30, H.J. Lu wrote:
> Since CET is only enabled for x86-64, move dl-cet.[ch] to x86_64
> directories.

LGTM, thanks.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>

> ---
>  sysdeps/unix/sysv/linux/x86/dl-cet.h    | 63 -------------------------
>  sysdeps/unix/sysv/linux/x86_64/dl-cet.h | 47 +++++++++++++++++-
>  sysdeps/{x86 => x86_64}/dl-cet.c        |  0
>  3 files changed, 46 insertions(+), 64 deletions(-)
>  delete mode 100644 sysdeps/unix/sysv/linux/x86/dl-cet.h
>  rename sysdeps/{x86 => x86_64}/dl-cet.c (100%)
> 
> diff --git a/sysdeps/unix/sysv/linux/x86/dl-cet.h b/sysdeps/unix/sysv/linux/x86/dl-cet.h
> deleted file mode 100644
> index c10773ab0e..0000000000
> --- a/sysdeps/unix/sysv/linux/x86/dl-cet.h
> +++ /dev/null
> @@ -1,63 +0,0 @@
> -/* Linux/x86 CET initializers function.
> -   Copyright (C) 2018-2024 Free Software Foundation, Inc.
> -
> -   The GNU C Library is free software; you can redistribute it and/or
> -   modify it under the terms of the GNU Lesser General Public
> -   License as published by the Free Software Foundation; either
> -   version 2.1 of the License, or (at your option) any later version.
> -
> -   The GNU C Library is distributed in the hope that it will be useful,
> -   but WITHOUT ANY WARRANTY; without even the implied warranty of
> -   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> -   Lesser General Public License for more details.
> -
> -   You should have received a copy of the GNU Lesser General Public
> -   License along with the GNU C Library; if not, see
> -   <https://www.gnu.org/licenses/>.  */
> -
> -#include <sys/prctl.h>
> -#include <asm/prctl.h>
> -
> -static __always_inline int
> -dl_cet_disable_cet (unsigned int cet_feature)
> -{
> -  if (cet_feature != GNU_PROPERTY_X86_FEATURE_1_SHSTK)
> -    return -1;
> -  long long int kernel_feature = ARCH_SHSTK_SHSTK;
> -  return (int) INTERNAL_SYSCALL_CALL (arch_prctl, ARCH_SHSTK_DISABLE,
> -				      kernel_feature);
> -}
> -
> -static __always_inline int
> -dl_cet_lock_cet (unsigned int cet_feature)
> -{
> -  if (cet_feature != GNU_PROPERTY_X86_FEATURE_1_SHSTK)
> -    return -1;
> -  /* Lock all SHSTK features.  */
> -  long long int kernel_feature = -1;
> -  return (int) INTERNAL_SYSCALL_CALL (arch_prctl, ARCH_SHSTK_LOCK,
> -				      kernel_feature);
> -}
> -
> -static __always_inline unsigned int
> -dl_cet_get_cet_status (void)
> -{
> -  unsigned long long kernel_feature;
> -  unsigned int status = 0;
> -  if (INTERNAL_SYSCALL_CALL (arch_prctl, ARCH_SHSTK_STATUS,
> -			     &kernel_feature) == 0)
> -    {
> -      if ((kernel_feature & ARCH_SHSTK_SHSTK) != 0)
> -	status = GNU_PROPERTY_X86_FEATURE_1_SHSTK;
> -    }
> -  return status;
> -}
> -
> -/* Enable shadow stack with a macro to avoid shadow stack underflow.  */
> -#define ENABLE_X86_CET(cet_feature)				\
> -  if ((cet_feature & GNU_PROPERTY_X86_FEATURE_1_SHSTK))		\
> -    {								\
> -      long long int kernel_feature = ARCH_SHSTK_SHSTK;		\
> -      INTERNAL_SYSCALL_CALL (arch_prctl, ARCH_SHSTK_ENABLE,	\
> -			     kernel_feature);			\
> -    }

Ok.

> diff --git a/sysdeps/unix/sysv/linux/x86_64/dl-cet.h b/sysdeps/unix/sysv/linux/x86_64/dl-cet.h
> index c89dd6bd42..94e9b9aa86 100644
> --- a/sysdeps/unix/sysv/linux/x86_64/dl-cet.h
> +++ b/sysdeps/unix/sysv/linux/x86_64/dl-cet.h
> @@ -15,8 +15,53 @@
>     License along with the GNU C Library; if not, see
>     <https://www.gnu.org/licenses/>.  */
>  
> +#include <sys/prctl.h>
> +#include <asm/prctl.h>
>  #include <cpu-features-offsets.h>
> -#include_next <dl-cet.h>
> +
> +static __always_inline int
> +dl_cet_disable_cet (unsigned int cet_feature)
> +{
> +  if (cet_feature != GNU_PROPERTY_X86_FEATURE_1_SHSTK)
> +    return -1;
> +  long long int kernel_feature = ARCH_SHSTK_SHSTK;
> +  return (int) INTERNAL_SYSCALL_CALL (arch_prctl, ARCH_SHSTK_DISABLE,
> +				      kernel_feature);
> +}
> +
> +static __always_inline int
> +dl_cet_lock_cet (unsigned int cet_feature)
> +{
> +  if (cet_feature != GNU_PROPERTY_X86_FEATURE_1_SHSTK)
> +    return -1;
> +  /* Lock all SHSTK features.  */
> +  long long int kernel_feature = -1;
> +  return (int) INTERNAL_SYSCALL_CALL (arch_prctl, ARCH_SHSTK_LOCK,
> +				      kernel_feature);
> +}
> +
> +static __always_inline unsigned int
> +dl_cet_get_cet_status (void)
> +{
> +  unsigned long long kernel_feature;
> +  unsigned int status = 0;
> +  if (INTERNAL_SYSCALL_CALL (arch_prctl, ARCH_SHSTK_STATUS,
> +			     &kernel_feature) == 0)
> +    {
> +      if ((kernel_feature & ARCH_SHSTK_SHSTK) != 0)
> +	status = GNU_PROPERTY_X86_FEATURE_1_SHSTK;
> +    }
> +  return status;
> +}
> +
> +/* Enable shadow stack with a macro to avoid shadow stack underflow.  */
> +#define ENABLE_X86_CET(cet_feature)				\
> +  if ((cet_feature & GNU_PROPERTY_X86_FEATURE_1_SHSTK))		\
> +    {								\
> +      long long int kernel_feature = ARCH_SHSTK_SHSTK;		\
> +      INTERNAL_SYSCALL_CALL (arch_prctl, ARCH_SHSTK_ENABLE,	\
> +			     kernel_feature);			\
> +    }
>  
>  #define X86_STRINGIFY_1(x)	#x
>  #define X86_STRINGIFY(x)	X86_STRINGIFY_1 (x)

Ok.

> diff --git a/sysdeps/x86/dl-cet.c b/sysdeps/x86_64/dl-cet.c
> similarity index 100%
> rename from sysdeps/x86/dl-cet.c
> rename to sysdeps/x86_64/dl-cet.c

Ok.

Re: [PATCH 3/4] x86-64/cet: Move check-cet.awk to x86_64

[Adhemerval Zanella Netto]

On 09/01/24 16:30, H.J. Lu wrote:
> ---
>  sysdeps/x86_64/Makefile               | 2 +-
>  sysdeps/{x86 => x86_64}/check-cet.awk | 0
>  2 files changed, 1 insertion(+), 1 deletion(-)
>  rename sysdeps/{x86 => x86_64}/check-cet.awk (100%)
> 
> diff --git a/sysdeps/x86_64/Makefile b/sysdeps/x86_64/Makefile
> index 98f0e04f90..abb8b354af 100644
> --- a/sysdeps/x86_64/Makefile
> +++ b/sysdeps/x86_64/Makefile
> @@ -468,7 +468,7 @@ $(cet-built-dso:=.note): %.note: %
>  	mv -f $@T $@
>  common-generated += $(cet-built-dso:$(common-objpfx)%=%.note)
>  
> -$(objpfx)check-cet.out: $(..)sysdeps/x86/check-cet.awk \
> +$(objpfx)check-cet.out: $(..)/sysdeps/x86_64/check-cet.awk \
>  			$(cet-built-dso:=.note)
>  	LC_ALL=C $(AWK) -f $^ > $@; \
>  	$(evaluate-test)
> diff --git a/sysdeps/x86/check-cet.awk b/sysdeps/x86_64/check-cet.awk
> similarity index 100%
> rename from sysdeps/x86/check-cet.awk
> rename to sysdeps/x86_64/check-cet.awk

LGTM, thanks.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>

Re: [PATCH 4/4] i386: Remove CET support bits

[Adhemerval Zanella Netto]

On 09/01/24 16:30, H.J. Lu wrote:
> 1. Remove _dl_runtime_resolve_shstk and _dl_runtime_profile_shstk.
> 2. Move CET offsets from x86 cpu-features-offsets.sym to x86-64
> features-offsets.sym.
> 3. Rename x86 cet-control.h to x86-64 feature-control.h since it is only
> for x86-64 and also used for PLT rewrite.
> 4. Add x86-64 ldsodefs.h to include feature-control.h.
> 5. Change TUNABLE_CALLBACK (set_plt_rewrite) to x86-64 only.
> 6. Move x86 dl-procruntime.c to x86-64.

LGTM, thanks.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>

> ---
>  sysdeps/i386/dl-machine.h                     | 11 +--
>  sysdeps/i386/dl-trampoline.S                  | 69 -------------------
>  sysdeps/unix/sysv/linux/x86_64/dl-cet.h       |  2 +-
>  sysdeps/x86/cpu-features-offsets.sym          |  2 -
>  sysdeps/x86/cpu-features.c                    |  4 +-
>  sysdeps/x86/ldsodefs.h                        |  1 -
>  sysdeps/x86_64/Makefile                       |  2 +-
>  sysdeps/{x86 => x86_64}/dl-procruntime.c      |  2 +-
>  sysdeps/x86_64/dl-trampoline.S                |  1 +
>  .../feature-control.h}                        |  0
>  sysdeps/x86_64/features-offsets.sym           |  6 ++
>  sysdeps/x86_64/ldsodefs.h                     | 26 +++++++
>  12 files changed, 41 insertions(+), 85 deletions(-)
>  rename sysdeps/{x86 => x86_64}/dl-procruntime.c (97%)
>  rename sysdeps/{x86/cet-control.h => x86_64/feature-control.h} (100%)
>  create mode 100644 sysdeps/x86_64/features-offsets.sym
>  create mode 100644 sysdeps/x86_64/ldsodefs.h
> 
> diff --git a/sysdeps/i386/dl-machine.h b/sysdeps/i386/dl-machine.h
> index c69ae165ac..fc1ef96587 100644
> --- a/sysdeps/i386/dl-machine.h
> +++ b/sysdeps/i386/dl-machine.h
> @@ -65,9 +65,6 @@ elf_machine_runtime_setup (struct link_map *l, struct r_scope_elem *scope[],
>    extern void _dl_runtime_profile (Elf32_Word) attribute_hidden;
>    extern void _dl_runtime_resolve_shstk (Elf32_Word) attribute_hidden;
>    extern void _dl_runtime_profile_shstk (Elf32_Word) attribute_hidden;
> -  /* Check if SHSTK is enabled by kernel.  */
> -  bool shstk_enabled
> -    = (GL(dl_x86_feature_1) & GNU_PROPERTY_X86_FEATURE_1_SHSTK) != 0;
>  
>    if (l->l_info[DT_JMPREL] && lazy)
>      {
> @@ -95,9 +92,7 @@ elf_machine_runtime_setup (struct link_map *l, struct r_scope_elem *scope[],
>  #ifdef SHARED
>        if (__glibc_unlikely (profile))
>  	{
> -	  got[2] = (shstk_enabled
> -		    ? (Elf32_Addr) &_dl_runtime_profile_shstk
> -		    : (Elf32_Addr) &_dl_runtime_profile);
> +	  got[2] = (Elf32_Addr) &_dl_runtime_profile;
>  
>  	  if (GLRO(dl_profile) != NULL
>  	      && _dl_name_match_p (GLRO(dl_profile), l))
> @@ -109,9 +104,7 @@ elf_machine_runtime_setup (struct link_map *l, struct r_scope_elem *scope[],
>  #endif
>  	/* This function will get called to fix up the GOT entry indicated by
>  	   the offset on the stack, and then jump to the resolved address.  */
> -	got[2] = (shstk_enabled
> -		  ? (Elf32_Addr) &_dl_runtime_resolve_shstk
> -		  : (Elf32_Addr) &_dl_runtime_resolve);
> +	got[2] = (Elf32_Addr) &_dl_runtime_resolve;
>      }
>  
>    return lazy;

Ok.

> diff --git a/sysdeps/i386/dl-trampoline.S b/sysdeps/i386/dl-trampoline.S
> index 2632020145..6c14d463b6 100644
> --- a/sysdeps/i386/dl-trampoline.S
> +++ b/sysdeps/i386/dl-trampoline.S
> @@ -44,76 +44,7 @@ _dl_runtime_resolve:
>  	cfi_endproc
>  	.size _dl_runtime_resolve, .-_dl_runtime_resolve
>  
> -# The SHSTK compatible version.
> -	.text
> -	.globl _dl_runtime_resolve_shstk
> -	.type _dl_runtime_resolve_shstk, @function
> -	cfi_startproc
> -	.align 16
> -_dl_runtime_resolve_shstk:
> -	cfi_adjust_cfa_offset (8)
> -	pushl %eax		# Preserve registers otherwise clobbered.
> -	cfi_adjust_cfa_offset (4)
> -	pushl %edx
> -	cfi_adjust_cfa_offset (4)
> -	movl 12(%esp), %edx	# Copy args pushed by PLT in register.  Note
> -	movl 8(%esp), %eax	# that `fixup' takes its parameters in regs.
> -	call _dl_fixup		# Call resolver.
> -	movl (%esp), %edx	# Get register content back.
> -	movl %eax, %ecx		# Store the function address.
> -	movl 4(%esp), %eax	# Get register content back.
> -	addl $16, %esp		# Adjust stack: PLT1 + PLT2 + %eax + %edx
> -	cfi_adjust_cfa_offset (-16)
> -	jmp *%ecx		# Jump to function address.
> -	cfi_endproc
> -	.size _dl_runtime_resolve_shstk, .-_dl_runtime_resolve_shstk
> -
>  #if !defined PROF && defined SHARED
> -# The SHSTK compatible version.
> -	.globl _dl_runtime_profile_shstk
> -	.type _dl_runtime_profile_shstk, @function
> -	cfi_startproc
> -	.align 16
> -_dl_runtime_profile_shstk:
> -	cfi_adjust_cfa_offset (8)
> -	pushl %esp
> -	cfi_adjust_cfa_offset (4)
> -	addl $8, (%esp)		# Account for the pushed PLT data
> -	pushl %ebp
> -	cfi_adjust_cfa_offset (4)
> -	pushl %eax		# Preserve registers otherwise clobbered.
> -	cfi_adjust_cfa_offset (4)
> -	pushl %ecx
> -	cfi_adjust_cfa_offset (4)
> -	pushl %edx
> -	cfi_adjust_cfa_offset (4)
> -	movl %esp, %ecx
> -	subl $8, %esp
> -	cfi_adjust_cfa_offset (8)
> -	movl $-1, 4(%esp)
> -	leal 4(%esp), %edx
> -	movl %edx, (%esp)
> -	pushl %ecx		# Address of the register structure
> -	cfi_adjust_cfa_offset (4)
> -	movl 40(%esp), %ecx	# Load return address
> -	movl 36(%esp), %edx	# Copy args pushed by PLT in register.  Note
> -	movl 32(%esp), %eax	# that `fixup' takes its parameters in regs.
> -	call _dl_profile_fixup	# Call resolver.
> -	cfi_adjust_cfa_offset (-8)
> -	movl (%esp), %edx
> -	testl %edx, %edx
> -	jns 1f
> -	movl 4(%esp), %edx	# Get register content back.
> -	movl %eax, %ecx		# Store the function address.
> -	movl 12(%esp), %eax	# Get register content back.
> -	# Adjust stack: PLT1 + PLT2 + %esp + %ebp + %eax + %ecx + %edx
> -	# + free.
> -	addl $32, %esp
> -	cfi_adjust_cfa_offset (-32)
> -	jmp *%ecx		# Jump to function address.
> -	cfi_endproc
> -	.size _dl_runtime_profile_shstk, .-_dl_runtime_profile_shstk
> -
>  	.globl _dl_runtime_profile
>  	.type _dl_runtime_profile, @function
>  	cfi_startproc

Ok.

> diff --git a/sysdeps/unix/sysv/linux/x86_64/dl-cet.h b/sysdeps/unix/sysv/linux/x86_64/dl-cet.h
> index 94e9b9aa86..a00c7ee662 100644
> --- a/sysdeps/unix/sysv/linux/x86_64/dl-cet.h
> +++ b/sysdeps/unix/sysv/linux/x86_64/dl-cet.h
> @@ -17,7 +17,7 @@
>  
>  #include <sys/prctl.h>
>  #include <asm/prctl.h>
> -#include <cpu-features-offsets.h>
> +#include <features-offsets.h>
>  
>  static __always_inline int
>  dl_cet_disable_cet (unsigned int cet_feature)

Ok.

> diff --git a/sysdeps/x86/cpu-features-offsets.sym b/sysdeps/x86/cpu-features-offsets.sym
> index 5429f60632..6a8fd29813 100644
> --- a/sysdeps/x86/cpu-features-offsets.sym
> +++ b/sysdeps/x86/cpu-features-offsets.sym
> @@ -2,6 +2,4 @@
>  
>  #include <ldsodefs.h>
>  
> -RTLD_GLOBAL_RO_DL_X86_CPU_FEATURES_OFFSET offsetof (struct rtld_global_ro, _dl_x86_cpu_features)
>  XSAVE_STATE_SIZE_OFFSET	offsetof (struct cpu_features, xsave_state_size)
> -RTLD_GLOBAL_DL_X86_FEATURE_1_OFFSET offsetof (struct rtld_global, _dl_x86_feature_1)

Ok.

> diff --git a/sysdeps/x86/cpu-features.c b/sysdeps/x86/cpu-features.c
> index 9ca307f521..46bdaffbc2 100644
> --- a/sysdeps/x86/cpu-features.c
> +++ b/sysdeps/x86/cpu-features.c
> @@ -27,7 +27,7 @@
>  extern void TUNABLE_CALLBACK (set_hwcaps) (tunable_val_t *)
>    attribute_hidden;
>  
> -#ifdef SHARED
> +#if defined SHARED && defined __x86_64__
>  static void
>  TUNABLE_CALLBACK (set_plt_rewrite) (tunable_val_t *valp)
>  {
> @@ -1125,8 +1125,10 @@ no_cpuid:
>  #endif
>  
>  #ifdef SHARED
> +# ifdef __x86_64__
>    TUNABLE_GET (plt_rewrite, tunable_val_t *,
>  	       TUNABLE_CALLBACK (set_plt_rewrite));
> +# endif
>  #else
>    /* NB: In libc.a, call init_cacheinfo.  */
>    init_cacheinfo ();

Ok.

> diff --git a/sysdeps/x86/ldsodefs.h b/sysdeps/x86/ldsodefs.h
> index b2a6d71513..50dc81c022 100644
> --- a/sysdeps/x86/ldsodefs.h
> +++ b/sysdeps/x86/ldsodefs.h
> @@ -61,7 +61,6 @@ struct La_x32_retval;
>  				     struct La_x86_64_retval *,		\
>  				     const char *)
>  
> -#include <cet-control.h>
>  #include_next <ldsodefs.h>
>  
>  #endif

Ok.

> diff --git a/sysdeps/x86_64/Makefile b/sysdeps/x86_64/Makefile
> index abb8b354af..10a253e4f1 100644
> --- a/sysdeps/x86_64/Makefile
> +++ b/sysdeps/x86_64/Makefile
> @@ -10,7 +10,7 @@ LDFLAGS-rtld += -Wl,-z,nomark-plt
>  endif
>  
>  ifeq ($(subdir),csu)
> -gen-as-const-headers += link-defines.sym
> +gen-as-const-headers += features-offsets.sym link-defines.sym
>  endif
>  
>  ifeq ($(subdir),gmon)

Ok.

> diff --git a/sysdeps/x86/dl-procruntime.c b/sysdeps/x86_64/dl-procruntime.c
> similarity index 97%
> rename from sysdeps/x86/dl-procruntime.c
> rename to sysdeps/x86_64/dl-procruntime.c

Ok.

> index 15b3d0d878..7078581778 100644
> --- a/sysdeps/x86/dl-procruntime.c
> +++ b/sysdeps/x86_64/dl-procruntime.c
> @@ -1,4 +1,4 @@
> -/* Data for processor runtime information.  x86 version.
> +/* Data for processor runtime information.  x86-64 version.
>     Copyright (C) 2018-2024 Free Software Foundation, Inc.
>     This file is part of the GNU C Library.
>  

Ok.

> diff --git a/sysdeps/x86_64/dl-trampoline.S b/sysdeps/x86_64/dl-trampoline.S
> index 4c1ba5c9af..b2e7e0f69b 100644
> --- a/sysdeps/x86_64/dl-trampoline.S
> +++ b/sysdeps/x86_64/dl-trampoline.S
> @@ -19,6 +19,7 @@
>  #include <config.h>
>  #include <sysdep.h>
>  #include <cpu-features-offsets.h>
> +#include <features-offsets.h>
>  #include <link-defines.h>
>  #include <isa-level.h>
>  

Ok.

> diff --git a/sysdeps/x86/cet-control.h b/sysdeps/x86_64/feature-control.h
> similarity index 100%
> rename from sysdeps/x86/cet-control.h
> rename to sysdeps/x86_64/feature-control.h
> diff --git a/sysdeps/x86_64/features-offsets.sym b/sysdeps/x86_64/features-offsets.sym
> new file mode 100644
> index 0000000000..9e4be3393a
> --- /dev/null
> +++ b/sysdeps/x86_64/features-offsets.sym
> @@ -0,0 +1,6 @@
> +#define SHARED 1
> +
> +#include <ldsodefs.h>
> +
> +RTLD_GLOBAL_RO_DL_X86_CPU_FEATURES_OFFSET offsetof (struct rtld_global_ro, _dl_x86_cpu_features)
> +RTLD_GLOBAL_DL_X86_FEATURE_1_OFFSET offsetof (struct rtld_global, _dl_x86_feature_1)

Ok.

> diff --git a/sysdeps/x86_64/ldsodefs.h b/sysdeps/x86_64/ldsodefs.h
> new file mode 100644
> index 0000000000..0f468ddf5b
> --- /dev/null
> +++ b/sysdeps/x86_64/ldsodefs.h
> @@ -0,0 +1,26 @@
> +/* Run-time dynamic linker data structures for loaded ELF shared objects.
> +   x86-64 version.
> +   Copyright (C) 2024 Free Software Foundation, Inc.
> +   This file is part of the GNU C Library.
> +
> +   The GNU C Library is free software; you can redistribute it and/or
> +   modify it under the terms of the GNU Lesser General Public
> +   License as published by the Free Software Foundation; either
> +   version 2.1 of the License, or (at your option) any later version.
> +
> +   The GNU C Library is distributed in the hope that it will be useful,
> +   but WITHOUT ANY WARRANTY; without even the implied warranty of
> +   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> +   Lesser General Public License for more details.
> +
> +   You should have received a copy of the GNU Lesser General Public
> +   License along with the GNU C Library; if not, see
> +   <https://www.gnu.org/licenses/>.  */
> +
> +#ifndef	_X86_64_LDSODEFS_H
> +#define	_X86_64_LDSODEFS_H	1
> +
> +#include <feature-control.h>
> +#include_next <ldsodefs.h>
> +
> +#endif

Ok.

Re: [PATCH 1/4] x86: Move x86-64 shadow stack startup codes

[H.J. Lu]

On Tue, Jan 9, 2024 at 11:51 AM Adhemerval Zanella Netto
<adhemerval.zanella@linaro.org> wrote:
>
>
>
> On 09/01/24 16:30, H.J. Lu wrote:
> > Add sysdeps/i386/libc-start.h and move x86-64 shadow stack startup codes
> > to sysdeps/x86_64/libc-start.h
> > ---
> >  sysdeps/i386/libc-start.h            | 25 +++++++++++++++++++++++++
> >  sysdeps/{x86 => x86_64}/libc-start.h |  2 +-
> >  2 files changed, 26 insertions(+), 1 deletion(-)
> >  create mode 100644 sysdeps/i386/libc-start.h
> >  rename sysdeps/{x86 => x86_64}/libc-start.h (98%)
> >
> > diff --git a/sysdeps/i386/libc-start.h b/sysdeps/i386/libc-start.h
> > new file mode 100644
> > index 0000000000..c9b7d3614e
> > --- /dev/null
> > +++ b/sysdeps/i386/libc-start.h
> > @@ -0,0 +1,25 @@
> > +/* i386 definitions for libc main startup.
> > +   Copyright (C) 2018-2024 Free Software Foundation, Inc.
> > +   This file is part of the GNU C Library.
> > +
> > +   The GNU C Library is free software; you can redistribute it and/or
> > +   modify it under the terms of the GNU Lesser General Public
> > +   License as published by the Free Software Foundation; either
> > +   version 2.1 of the License, or (at your option) any later version.
> > +
> > +   The GNU C Library is distributed in the hope that it will be useful,
> > +   but WITHOUT ANY WARRANTY; without even the implied warranty of
> > +   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> > +   Lesser General Public License for more details.
> > +
> > +   You should have received a copy of the GNU Lesser General Public
> > +   License along with the GNU C Library; if not, see
> > +   <https://www.gnu.org/licenses/>.  */
> > +
> > +#ifndef SHARED
> > +# define ARCH_SETUP_IREL() apply_irel ()
> > +# define ARCH_APPLY_IREL()
> > +# ifndef ARCH_SETUP_TLS
> > +#  define ARCH_SETUP_TLS() __libc_setup_tls ()
> > +# endif
> > +#endif /* !SHARED */
>
> I think you can just omit this file and use the generic one instead
> (sysdeps/generic/libc-start.h).

I sent out the v2 patches.  Changes in v2:

1. Remove sysdeps/i386/libc-start.h.
2. Replace x86 to x86-64 in comments in sysdeps/x86_64/dl-cet.c and
sysdeps/x86_64/feature-control.h.
3. Replace _CET_CONTROL_H with _X86_64_FEATURE_CONTROL_H in
sysdeps/x86_64/feature-control.h.

> > diff --git a/sysdeps/x86/libc-start.h b/sysdeps/x86_64/libc-start.h
> > similarity index 98%
> > rename from sysdeps/x86/libc-start.h
> > rename to sysdeps/x86_64/libc-start.h
> > index c3cc05888d..63fef17029 100644
> > --- a/sysdeps/x86/libc-start.h
> > +++ b/sysdeps/x86_64/libc-start.h
> > @@ -1,4 +1,4 @@
> > -/* X86 definitions for libc main startup.
> > +/* x86-64 definitions for libc main startup.
> >     Copyright (C) 2018-2024 Free Software Foundation, Inc.
> >     This file is part of the GNU C Library.
> >
>
> Ok.



-- 
H.J.

Re: [PATCH 3/4] x86-64/cet: Move check-cet.awk to x86_64

[Andreas Schwab]

On Jan 09 2024, H.J. Lu wrote:

> -$(objpfx)check-cet.out: $(..)sysdeps/x86/check-cet.awk \
> +$(objpfx)check-cet.out: $(..)/sysdeps/x86_64/check-cet.awk \
                                ^
Remove that.

-- 
Andreas Schwab, schwab@linux-m68k.org
GPG Key fingerprint = 7578 EB47 D4E5 4D69 2510  2552 DF73 E780 A9DA AEC1
"And now for something completely different."

Re: [PATCH 3/4] x86-64/cet: Move check-cet.awk to x86_64

[H.J. Lu]

On Tue, Jan 9, 2024 at 12:16 PM Andreas Schwab <schwab@linux-m68k.org> wrote:
>
> On Jan 09 2024, H.J. Lu wrote:
>
> > -$(objpfx)check-cet.out: $(..)sysdeps/x86/check-cet.awk \
> > +$(objpfx)check-cet.out: $(..)/sysdeps/x86_64/check-cet.awk \
>                                 ^
> Remove that.
>

Will fix it.

Thanks.

-- 
H.J.