From 7563dc64585324f443f5ac107eb6d89ee813a2d2 Mon Sep 17 00:00:00 2001 From: Tony Breeds Date: Tue, 2 Sep 2008 16:50:38 +1000 Subject: powerpc: Work around gcc's -fno-omit-frame-pointer bug This bug is causing random crashes (http://bugzilla.kernel.org/show_bug.cgi?id=11414). -fno-omit-frame-pointer is only needed on powerpc when -pg is also supplied, and there is a gcc bug that causes incorrect code generation on 32-bit powerpc when -fno-omit-frame-pointer is used---it uses stack locations below the stack pointer, which is not allowed by the ABI because those locations can and sometimes do get corrupted by an interrupt. This ensures that CONFIG_FRAME_POINTER is only selected by ftrace. When CONFIG_FTRACE is enabled we also pass -mno-sched-epilog to work around the gcc codegen bug. Patch based on work by: Andreas Schwab Segher Boessenkool Signed-off-by: Tony Breeds Signed-off-by: Paul Mackerras --- arch/powerpc/kernel/Makefile | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) (limited to 'arch/powerpc/kernel') diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile index 64f5948ebc9..946daea780f 100644 --- a/arch/powerpc/kernel/Makefile +++ b/arch/powerpc/kernel/Makefile @@ -14,12 +14,13 @@ endif ifdef CONFIG_FTRACE # Do not trace early boot code -CFLAGS_REMOVE_cputable.o = -pg -CFLAGS_REMOVE_prom_init.o = -pg +CFLAGS_REMOVE_cputable.o = -pg -mno-sched-epilog +CFLAGS_REMOVE_prom_init.o = -pg -mno-sched-epilog +CFLAGS_REMOVE_btext.o = -pg -mno-sched-epilog ifdef CONFIG_DYNAMIC_FTRACE # dynamic ftrace setup. -CFLAGS_REMOVE_ftrace.o = -pg +CFLAGS_REMOVE_ftrace.o = -pg -mno-sched-epilog endif endif -- cgit v1.2.3