powerpc/64: Add CONFIG_PPC_BARRIER_NOSPEC

Add a config symbol to encode which platforms support the
barrier_nospec speculation barrier. Currently this is just Book3S 64
but we will add Book3E in a future patch.

Signed-off-by: Diana Craciun <diana.craciun@nxp.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index ee38fce075ee4d601e2cc4103c01209f11d53618..846c89ed7fa3b9c2973edd3eca9d998c9485e5c1 100644 (file)
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -165,7 +165,7 @@ config PPC
        select GENERIC_CLOCKEVENTS_BROADCAST    if SMP
        select GENERIC_CMOS_UPDATE
        select GENERIC_CPU_AUTOPROBE
-       select GENERIC_CPU_VULNERABILITIES      if PPC_BOOK3S_64
+       select GENERIC_CPU_VULNERABILITIES      if PPC_BARRIER_NOSPEC
        select GENERIC_IRQ_SHOW
        select GENERIC_IRQ_SHOW_LEVEL
        select GENERIC_SMP_IDLE_THREAD
@@ -242,6 +242,11 @@ config PPC
        # Please keep this list sorted alphabetically.
        #
 
+config PPC_BARRIER_NOSPEC
+    bool
+    default y
+    depends on PPC_BOOK3S_64
+
 config GENERIC_CSUM
        def_bool n
 

diff --git a/arch/powerpc/include/asm/barrier.h b/arch/powerpc/include/asm/barrier.h
index de1316874e450003e98ead3cbfbf3d87ffab75a5..cdc6960506e2b850c19c16a48f3ab9327fcb1cc3 100644 (file)
--- a/arch/powerpc/include/asm/barrier.h
+++ b/arch/powerpc/include/asm/barrier.h
@@ -78,7 +78,7 @@ do {                                                                  \
        ___p1;                                                          \
 })
 
-#ifdef CONFIG_PPC_BOOK3S_64
+#ifdef CONFIG_PPC_BARRIER_NOSPEC
 /*
  * Prevent execution of subsequent instructions until preceding branches have
  * been fully resolved and are no longer executing speculatively.
@@ -88,10 +88,10 @@ do {                                                                        \
 // This also acts as a compiler barrier due to the memory clobber.
 #define barrier_nospec() asm (stringify_in_c(barrier_nospec_asm) ::: "memory")
 
-#else /* !CONFIG_PPC_BOOK3S_64 */
+#else /* !CONFIG_PPC_BARRIER_NOSPEC */
 #define barrier_nospec_asm
 #define barrier_nospec()
-#endif
+#endif /* CONFIG_PPC_BARRIER_NOSPEC */
 
 #include <asm-generic/barrier.h>
 

diff --git a/arch/powerpc/include/asm/setup.h b/arch/powerpc/include/asm/setup.h
index 8721fd004291d43c0bd08987abb96cc6dda90143..8205f9fdfd6760840f022fadfae2f43fc9e53b3f 100644 (file)
--- a/arch/powerpc/include/asm/setup.h
+++ b/arch/powerpc/include/asm/setup.h
@@ -56,7 +56,7 @@ void setup_barrier_nospec(void);
 void do_barrier_nospec_fixups(bool enable);
 extern bool barrier_nospec_enabled;
 
-#ifdef CONFIG_PPC_BOOK3S_64
+#ifdef CONFIG_PPC_BARRIER_NOSPEC
 void do_barrier_nospec_fixups_range(bool enable, void *start, void *end);
 #else
 static inline void do_barrier_nospec_fixups_range(bool enable, void *start, void *end) { };

diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile
index 2b4c40b255e4d385ccb087dd88936e85bbc17d55..dbe2cf04b40603769d446fe080dcc0732f3be6b7 100644 (file)
--- a/arch/powerpc/kernel/Makefile
+++ b/arch/powerpc/kernel/Makefile
@@ -42,9 +42,10 @@ obj-$(CONFIG_VDSO32)         += vdso32/
 obj-$(CONFIG_PPC_WATCHDOG)     += watchdog.o
 obj-$(CONFIG_HAVE_HW_BREAKPOINT)       += hw_breakpoint.o
 obj-$(CONFIG_PPC_BOOK3S_64)    += cpu_setup_ppc970.o cpu_setup_pa6t.o
-obj-$(CONFIG_PPC_BOOK3S_64)    += cpu_setup_power.o security.o
+obj-$(CONFIG_PPC_BOOK3S_64)    += cpu_setup_power.o
 obj-$(CONFIG_PPC_BOOK3S_64)    += mce.o mce_power.o
 obj-$(CONFIG_PPC_BOOK3E_64)    += exceptions-64e.o idle_book3e.o
+obj-$(CONFIG_PPC_BARRIER_NOSPEC) += security.o
 obj-$(CONFIG_PPC64)            += vdso64/
 obj-$(CONFIG_ALTIVEC)          += vecemu.o
 obj-$(CONFIG_PPC_970_NAP)      += idle_power4.o

diff --git a/arch/powerpc/kernel/module.c b/arch/powerpc/kernel/module.c
index 1b3c6835e7303b094417dc7528ed8b141ef45703..77371c9ef3d8f9fd46894e47a119e215ca86ae3a 100644 (file)
--- a/arch/powerpc/kernel/module.c
+++ b/arch/powerpc/kernel/module.c
@@ -72,13 +72,15 @@ int module_finalize(const Elf_Ehdr *hdr,
                do_feature_fixups(powerpc_firmware_features,
                                  (void *)sect->sh_addr,
                                  (void *)sect->sh_addr + sect->sh_size);
+#endif /* CONFIG_PPC64 */
 
+#ifdef CONFIG_PPC_BARRIER_NOSPEC
        sect = find_section(hdr, sechdrs, "__spec_barrier_fixup");
        if (sect != NULL)
                do_barrier_nospec_fixups_range(barrier_nospec_enabled,
                                  (void *)sect->sh_addr,
                                  (void *)sect->sh_addr + sect->sh_size);
-#endif
+#endif /* CONFIG_PPC_BARRIER_NOSPEC */
 
        sect = find_section(hdr, sechdrs, "__lwsync_fixup");
        if (sect != NULL)

diff --git a/arch/powerpc/kernel/vmlinux.lds.S b/arch/powerpc/kernel/vmlinux.lds.S
index 5baac79df97e584a2e27e7e9314a9ae0ece0fbd6..07ae018e550e1110e2743c6e63f8e065d59db42a 100644 (file)
--- a/arch/powerpc/kernel/vmlinux.lds.S
+++ b/arch/powerpc/kernel/vmlinux.lds.S
@@ -153,14 +153,16 @@ SECTIONS
                *(__rfi_flush_fixup)
                __stop___rfi_flush_fixup = .;
        }
+#endif /* CONFIG_PPC64 */
 
+#ifdef CONFIG_PPC_BARRIER_NOSPEC
        . = ALIGN(8);
        __spec_barrier_fixup : AT(ADDR(__spec_barrier_fixup) - LOAD_OFFSET) {
                __start___barrier_nospec_fixup = .;
                *(__barrier_nospec_fixup)
                __stop___barrier_nospec_fixup = .;
        }
-#endif
+#endif /* CONFIG_PPC_BARRIER_NOSPEC */
 
        EXCEPTION_TABLE(0)
 

diff --git a/arch/powerpc/lib/feature-fixups.c b/arch/powerpc/lib/feature-fixups.c
index 8b69f868298c41a59044dd633b831439ad426d0b..0e604b41b5d19549e14e4491e2fa79ddb38136c4 100644 (file)
--- a/arch/powerpc/lib/feature-fixups.c
+++ b/arch/powerpc/lib/feature-fixups.c
@@ -304,6 +304,9 @@ void do_barrier_nospec_fixups_range(bool enable, void *fixup_start, void *fixup_
        printk(KERN_DEBUG "barrier-nospec: patched %d locations\n", i);
 }
 
+#endif /* CONFIG_PPC_BOOK3S_64 */
+
+#ifdef CONFIG_PPC_BARRIER_NOSPEC
 void do_barrier_nospec_fixups(bool enable)
 {
        void *start, *end;
@@ -313,8 +316,7 @@ void do_barrier_nospec_fixups(bool enable)
 
        do_barrier_nospec_fixups_range(enable, start, end);
 }
-
-#endif /* CONFIG_PPC_BOOK3S_64 */
+#endif /* CONFIG_PPC_BARRIER_NOSPEC */
 
 void do_lwsync_fixups(unsigned long value, void *fixup_start, void *fixup_end)
 {