Revert "x86-64, modify_ldt: Make support for 16-bit segments a runtime option"

This reverts commit fa81511bb0bbb2b1aace3695ce869da9762624ff in
preparation of merging in the proper fix (espfix64).

Signed-off-by: H. Peter Anvin <hpa@zytor.com>

2 files changed, 1 insertions, 11 deletions

diff --git a/arch/x86/kernel/ldt.c b/arch/x86/kernel/ldt.c
index dcbbaa165bde..af1d14a9ebda 100644
--- a/arch/x86/kernel/ldt.c
+++ b/arch/x86/kernel/ldt.c
@@ -20,8 +20,6 @@
 #include <asm/mmu_context.h>
 #include <asm/syscalls.h>
 
-int sysctl_ldt16 = 0;
-
 #ifdef CONFIG_SMP
 static void flush_ldt(void *current_mm)
 {
@@ -236,7 +234,7 @@ static int write_ldt(void __user *ptr, unsigned long bytecount, int oldmode)
          * IRET leaking the high bits of the kernel stack address.
          */
 #ifdef CONFIG_X86_64
-        if (!ldt_info.seg_32bit && !sysctl_ldt16) {
+        if (!ldt_info.seg_32bit) {
                 error = -EINVAL;
                 goto out_unlock;
         }
diff --git a/arch/x86/vdso/vdso32-setup.c b/arch/x86/vdso/vdso32-setup.c
index e1f220e3ca68..00348980a3a6 100644
--- a/arch/x86/vdso/vdso32-setup.c
+++ b/arch/x86/vdso/vdso32-setup.c
@@ -39,7 +39,6 @@
 #ifdef CONFIG_X86_64
 #define vdso_enabled                    sysctl_vsyscall32
 #define arch_setup_additional_pages     syscall32_setup_pages
-extern int sysctl_ldt16;
 #endif
 
 /*
@@ -250,13 +249,6 @@ static struct ctl_table abi_table2[] = {
                 .mode           = 0644,
                 .proc_handler   = proc_dointvec
         },
-        {
-                .procname       = "ldt16",
-                .data           = &sysctl_ldt16,
-                .maxlen         = sizeof(int),
-                .mode           = 0644,
-                .proc_handler   = proc_dointvec
-        },
         {}
 };