This is backport for 5.4
(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@xxxxxxxxxxxxxxx # v4.9+
Reported-by: Erhard Furtner <erhard_f@xxxxxxxxxxx>
Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=215217
Link: https://lore.kernel.org/r/2bac55483b8daf5b1caa163a45fa5f9cdbe18be4.1640178426.git.christophe.leroy@xxxxxxxxxx
---
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 afbd47b0a75c..5819a577d267 100644
--- a/arch/powerpc/kernel/Makefile
+++ b/arch/powerpc/kernel/Makefile
@@ -13,6 +13,7 @@ CFLAGS_prom_init.o += -fPIC
CFLAGS_btext.o += -fPIC
endif
+CFLAGS_early_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 b8de3be10eb4..8656b8d2ce55 100644
--- a/arch/powerpc/lib/Makefile
+++ b/arch/powerpc/lib/Makefile
@@ -16,6 +16,9 @@ CFLAGS_code-patching.o += -DDISABLE_BRANCH_PROFILING
CFLAGS_feature-fixups.o += -DDISABLE_BRANCH_PROFILING
endif
+CFLAGS_code-patching.o += $(DISABLE_LATENT_ENTROPY_PLUGIN)
+CFLAGS_feature-fixups.o += $(DISABLE_LATENT_ENTROPY_PLUGIN)
+
obj-y += alloc.o code-patching.o feature-fixups.o pmem.o
ifndef CONFIG_KASAN
--
2.33.1
