From: Christophe Leroy christophe.leroy@csgroup.eu
commit f5668260b872e89b8d3942a8b7d4278aa9c2c981 upstream.
Commit 7c95d8893fb5 ("powerpc: Change calling convention for create_branch() et. al.") complexified the frame of function do_feature_fixups(), leading to GCC setting up a stack guard when CONFIG_STACKPROTECTOR is selected.
The problem is that do_feature_fixups() is called very early while 'current' in r2 is not set up yet and the code is still not at the final address used at link time.
So, like other instrumentation, stack protection needs to be deactivated for feature-fixups.c and code-patching.c
Fixes: 7c95d8893fb5 ("powerpc: Change calling convention for create_branch() et. al.") Cc: stable@vger.kernel.org # v5.8+ Reported-by: Jonathan Neuschaefer j.neuschaefer@gmx.net Signed-off-by: Christophe Leroy christophe.leroy@csgroup.eu Tested-by: Jonathan Neuschaefer j.neuschaefer@gmx.net Signed-off-by: Michael Ellerman mpe@ellerman.id.au Link: https://lore.kernel.org/r/b688fe82927b330349d9e44553363fa451ea4d95.161971511... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/powerpc/lib/Makefile | 3 +++ 1 file changed, 3 insertions(+)
--- a/arch/powerpc/lib/Makefile +++ b/arch/powerpc/lib/Makefile @@ -5,6 +5,9 @@
ccflags-$(CONFIG_PPC64) := $(NO_MINIMAL_TOC)
+CFLAGS_code-patching.o += -fno-stack-protector +CFLAGS_feature-fixups.o += -fno-stack-protector + CFLAGS_REMOVE_code-patching.o = $(CC_FLAGS_FTRACE) CFLAGS_REMOVE_feature-fixups.o = $(CC_FLAGS_FTRACE)