From 4c7f8900f1d8a0e464e7092f132a7e93f7c20f2f Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Sat, 23 Feb 2008 07:06:55 +0100 Subject: [PATCH] x86: stackprotector & PARAVIRT fix on paravirt enabled 64-bit kernels the paravirt ops do function calls themselves - which is bad with the stackprotector - for example pda_init() loads 0 into %gs and then does MSR_GS_BASE write (which modifies gs.base) - but that MSR write is a function call on paravirt, which with stackprotector tries to read the stack canary from the PDA ... crashing the bootup. the solution was suggested by Arjan van de Ven: to exclude paravirt.c from stackprotector, too many lowlevel functionality is in it. It's not like we'll have paravirt functions with character arrays on their stack anyway... Signed-off-by: Arjan van de Ven Signed-off-by: Ingo Molnar Signed-off-by: Thomas Gleixner --- arch/x86/kernel/Makefile | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile index 5e618c3b4720..8161e5a91ca9 100644 --- a/arch/x86/kernel/Makefile +++ b/arch/x86/kernel/Makefile @@ -14,6 +14,7 @@ nostackp := $(call cc-option, -fno-stack-protector) CFLAGS_vsyscall_64.o := $(PROFILING) -g0 $(nostackp) CFLAGS_hpet.o := $(nostackp) CFLAGS_tsc_64.o := $(nostackp) +CFLAGS_paravirt.o := $(nostackp) obj-y := process_$(BITS).o signal_$(BITS).o entry_$(BITS).o obj-y += traps_$(BITS).o irq_$(BITS).o