1 files changed, 18 insertions, 0 deletions

diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index 37fa30bada17..b1f8be33300d 100644
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -24,6 +24,24 @@ CFLAGS_vsyscall_64.o	:= $(PROFILING) -g0 $(nostackp)
 CFLAGS_hpet.o           := $(nostackp)
 CFLAGS_tsc.o            := $(nostackp)
 CFLAGS_paravirt.o       := $(nostackp)
+#
+# On x86_32, register frame is passed verbatim on stack as struct
+# pt_regs.  gcc considers the parameter to belong to the callee and
+# with -fstack-protector it copies pt_regs to the callee's stack frame
+# to put the structure after the stack canary causing changes made by
+# the exception handlers to be lost.  Turn off stack protector for all
+# files containing functions which take struct pt_regs from register
+# frame.
+#
+# The proper way to fix this is to teach gcc that the argument belongs
+# to the caller for these functions, oh well...
+#
+ifdef CONFIG_X86_32
+CFLAGS_process_32.o     := $(nostackp)
+CFLAGS_vm86_32.o        := $(nostackp)
+CFLAGS_signal.o         := $(nostackp)
+CFLAGS_traps.o          := $(nostackp)
+endif
 
 obj-y                   := process_$(BITS).o signal.o entry_$(BITS).o
 obj-y                   += traps.o irq.o irq_$(BITS).o dumpstack_$(BITS).o