i386: Remove CET support

CET is only support for x86_64, this patch reverts:

  - faaee1f07ed x86: Support shadow stack pointer in setjmp/longjmp.
  - be9ccd27c09 i386: Add _CET_ENDBR to indirect jump targets in
    add_n.S/sub_n.S
  - c02695d7764 x86/CET: Update vfork to prevent child return
  - 5d844e1b725 i386: Enable CET support in ucontext functions
  - 124bcde683 x86: Add _CET_ENDBR to functions in crti.S
  - 562837c002 x86: Add _CET_ENDBR to functions in dl-tlsdesc.S
  - f753fa7dea x86: Support IBT and SHSTK in Intel CET [BZ #21598]
  - 825b58f3fb i386-mcount.S: Add _CET_ENDBR to _mcount and __fentry__
  - 7e119cd582 i386: Use _CET_NOTRACK in i686/memcmp.S
  - 177824e232 i386: Use _CET_NOTRACK in memcmp-sse4.S
  - 0a899af097 i386: Use _CET_NOTRACK in memcpy-ssse3-rep.S
  - 7fb613361c i386: Use _CET_NOTRACK in memcpy-ssse3.S
  - 77a8ae0948 i386: Use _CET_NOTRACK in memset-sse2-rep.S
  - 00e7b76a8f i386: Use _CET_NOTRACK in memset-sse2.S
  - 90d15dc577 i386: Use _CET_NOTRACK in strcat-sse2.S
  - f1574581c7 i386: Use _CET_NOTRACK in strcpy-sse2.S
  - 4031d7484a i386/sub_n.S: Add a missing _CET_ENDBR to indirect jump
  - target
  -
Checked on i686-linux-gnu.

1 files changed, 0 insertions, 56 deletions

diff --git a/sysdeps/unix/sysv/linux/i386/getcontext.S b/sysdeps/unix/sysv/linux/i386/getcontext.S
index 3202ac002e..9c1ca3c263 100644
--- a/sysdeps/unix/sysv/linux/i386/getcontext.S
+++ b/sysdeps/unix/sysv/linux/i386/getcontext.S
@@ -17,7 +17,6 @@
    <https://www.gnu.org/licenses/>.  */
 
 #include <sysdep.h>
-#include <asm/prctl.h>
 
 #include "ucontext_i.h"
 
@@ -42,61 +41,6 @@ ENTRY(__getcontext)
 	movw	%fs, %dx
 	movl	%edx, oFS(%eax)
 
-#if SHSTK_ENABLED
-	/* Check if shadow stack is enabled.  */
-	testl	$X86_FEATURE_1_SHSTK, %gs:FEATURE_1_OFFSET
-	jz	L(no_shstk)
-
-	/* Save EAX in EDX.  */
-	movl	%eax, %edx
-
-	xorl	%eax, %eax
-	cmpl	%gs:SSP_BASE_OFFSET, %eax
-	jnz	L(shadow_stack_bound_recorded)
-
-	/* Save EBX in the first scratch register slot.  */
-	movl	%ebx, oSCRATCH1(%edx)
-
-	/* Get the base address and size of the default shadow stack
-	   which must be the current shadow stack since nothing has
-	   been recorded yet.  */
-	sub	$24, %esp
-	mov	%esp, %ecx
-	movl	$ARCH_CET_STATUS, %ebx
-	movl	$__NR_arch_prctl, %eax
-	ENTER_KERNEL
-	testl	%eax, %eax
-	jz	L(continue_no_err)
-
-	/* This should never happen.  */
-	hlt
-
-L(continue_no_err):
-	/* Restore EBX from the first scratch register slot.  */
-	movl	oSCRATCH1(%edx), %ebx
-
-	/* Record the base of the current shadow stack.  */
-	movl	8(%esp), %eax
-	movl	%eax, %gs:SSP_BASE_OFFSET
-	add	$24, %esp
-
-L(shadow_stack_bound_recorded):
-	/* Load address of the context data structure.  */
-	movl	4(%esp), %eax
-
-	/* Get the current shadow stack pointer.  */
-	rdsspd	%edx
-	/* NB: Save the caller's shadow stack so that we can jump back
-	   to the caller directly.  */
-	addl	$4, %edx
-	movl	%edx, oSSP(%eax)
-
-	/* Save the current shadow stack base in ucontext.  */
-	movl	%gs:SSP_BASE_OFFSET, %edx
-	movl	%edx, (oSSP + 4)(%eax)
-
-L(no_shstk):
-#endif
 	/* We have separate floating-point register content memory on the
 	   stack.  We use the __fpregs_mem block in the context.  Set the
 	   links up correctly.  */