The patch below does not apply to the 5.15-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From bba496656a73fc1d1330b49c7f82843836e9feb1 Mon Sep 17 00:00:00 2001 From: Christophe Leroy christophe.leroy@csgroup.eu Date: Wed, 22 Dec 2021 13:07:31 +0000 Subject: [PATCH] powerpc/32: Fix boot failure with GCC latent entropy plugin
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...
diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile index 5fa68c2ef1f8..36f3f5a8868d 100644 --- a/arch/powerpc/kernel/Makefile +++ b/arch/powerpc/kernel/Makefile @@ -11,6 +11,7 @@ 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 3e183f4b4bda..5d1881d2e39a 100644 --- a/arch/powerpc/lib/Makefile +++ b/arch/powerpc/lib/Makefile @@ -19,6 +19,9 @@ 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 += $(DISABLE_LATENT_ENTROPY_PLUGIN) + obj-y += alloc.o code-patching.o feature-fixups.o pmem.o
obj-$(CONFIG_CODE_PATCHING_SELFTEST) += test-code-patching.o