diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index 7cd01b71b5bdc8e7573edfecd9bda4fd0f542230..50a6dc871cc08734ea3926a59f235ee3a1bf0b3f 100644
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -299,8 +299,9 @@ struct tss_struct {
 
 #ifdef CONFIG_X86_32
 	/*
-	 * Space for the temporary SYSENTER stack:
+	 * Space for the temporary SYSENTER stack.
 	 */
+	unsigned long		SYSENTER_stack_canary;
 	unsigned long		SYSENTER_stack[64];
 #endif
 
diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
index 9f7c21c22477e59462d72e930d79a4c2a238a051..ee9a9792caeb3c8a2f75ec56fdd7fb96828e2f4f 100644
--- a/arch/x86/kernel/process.c
+++ b/arch/x86/kernel/process.c
@@ -57,6 +57,9 @@ __visible DEFINE_PER_CPU_SHARED_ALIGNED(struct tss_struct, cpu_tss) = {
 	  */
 	.io_bitmap		= { [0 ... IO_BITMAP_LONGS] = ~0 },
 #endif
+#ifdef CONFIG_X86_32
+	.SYSENTER_stack_canary	= STACK_END_MAGIC,
+#endif
 };
 EXPORT_PER_CPU_SYMBOL(cpu_tss);
 
diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c
index b0ddb81926f92bc7ecf64e862be3d35853fdadcf..49e2e775f507a23ec1a72ae69635d8f06b825ab1 100644
--- a/arch/x86/kernel/traps.c
+++ b/arch/x86/kernel/traps.c
@@ -713,6 +713,14 @@ dotraplinkage void do_debug(struct pt_regs *regs, long error_code)
 	debug_stack_usage_dec();
 
 exit:
+#if defined(CONFIG_X86_32)
+	/*
+	 * This is the most likely code path that involves non-trivial use
+	 * of the SYSENTER stack.  Check that we haven't overrun it.
+	 */
+	WARN(this_cpu_read(cpu_tss.SYSENTER_stack_canary) != STACK_END_MAGIC,
+	     "Overran or corrupted SYSENTER stack\n");
+#endif
 	ist_exit(regs);
 }
 NOKPROBE_SYMBOL(do_debug);