This is backport for 4.9
(cherry picked from commit bba496656a73fc1d1330b49c7f82843836e9feb1)
Boot fails with GCC latent entropy plugin enabled.
This is due to early boot functions trying to access 'latent_entropy' global data while the kernel is not relocated at its final destination yet.
As there is no way to tell GCC to use PTRRELOC() to access it, disable latent entropy plugin in early_32.o and feature-fixups.o and code-patching.o
Fixes: 38addce8b600 ("gcc-plugins: Add latent_entropy plugin") Cc: stable@vger.kernel.org # v4.9+ Reported-by: Erhard Furtner erhard_f@mailbox.org Signed-off-by: Christophe Leroy christophe.leroy@csgroup.eu Signed-off-by: Michael Ellerman mpe@ellerman.id.au Link: https://bugzilla.kernel.org/show_bug.cgi?id=215217 Link: https://lore.kernel.org/r/2bac55483b8daf5b1caa163a45fa5f9cdbe18be4.164017842... --- arch/powerpc/kernel/Makefile | 1 + arch/powerpc/lib/Makefile | 3 +++ 2 files changed, 4 insertions(+)
diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile index d80fbf0884ff..bc6c85788b84 100644 --- a/arch/powerpc/kernel/Makefile +++ b/arch/powerpc/kernel/Makefile @@ -14,6 +14,7 @@ CFLAGS_prom_init.o += -fPIC CFLAGS_btext.o += -fPIC endif
+CFLAGS_setup_32.o += $(DISABLE_LATENT_ENTROPY_PLUGIN) CFLAGS_cputable.o += $(DISABLE_LATENT_ENTROPY_PLUGIN) CFLAGS_prom_init.o += $(DISABLE_LATENT_ENTROPY_PLUGIN) CFLAGS_btext.o += $(DISABLE_LATENT_ENTROPY_PLUGIN) diff --git a/arch/powerpc/lib/Makefile b/arch/powerpc/lib/Makefile index 309361e86523..3e3370d126ae 100644 --- a/arch/powerpc/lib/Makefile +++ b/arch/powerpc/lib/Makefile @@ -9,6 +9,9 @@ ccflags-$(CONFIG_PPC64) := $(NO_MINIMAL_TOC) CFLAGS_REMOVE_code-patching.o = $(CC_FLAGS_FTRACE) CFLAGS_REMOVE_feature-fixups.o = $(CC_FLAGS_FTRACE)
+CFLAGS_code-patching.o += $(DISABLE_LATENT_ENTROPY_PLUGIN) +CFLAGS_feature-fixups.o += $(DISABLE_LATENT_ENTROPY_PLUGIN) + obj-y += string.o alloc.o crtsavres.o code-patching.o \ feature-fixups.o