summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorDiana Craciun <diana.craciun@nxp.com>2019-04-21 17:20:33 +0300
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2019-05-16 20:44:50 +0300
commit932e8acaa806376db8ed1f33d8c0159569b935ff (patch)
tree1631a3f17a87ffef6dec91b1fac105ed424c684a
parent4cbfad23be505ac25a32c4e93519353b8d75b5c3 (diff)
downloadlinux-932e8acaa806376db8ed1f33d8c0159569b935ff.tar.xz
powerpc/fsl: Add nospectre_v2 command line argument
commit f633a8ad636efb5d4bba1a047d4a0f1ef719aa06 upstream. When the command line argument is present, the Spectre variant 2 mitigations are disabled. Signed-off-by: Diana Craciun <diana.craciun@nxp.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r--arch/powerpc/include/asm/setup.h5
-rw-r--r--arch/powerpc/kernel/security.c21
2 files changed, 26 insertions, 0 deletions
diff --git a/arch/powerpc/include/asm/setup.h b/arch/powerpc/include/asm/setup.h
index 4d6446408a1b..d299479c770b 100644
--- a/arch/powerpc/include/asm/setup.h
+++ b/arch/powerpc/include/asm/setup.h
@@ -53,6 +53,11 @@ void do_barrier_nospec_fixups_range(bool enable, void *start, void *end);
static inline void do_barrier_nospec_fixups_range(bool enable, void *start, void *end) { };
#endif
+#ifdef CONFIG_PPC_FSL_BOOK3E
+void setup_spectre_v2(void);
+#else
+static inline void setup_spectre_v2(void) {};
+#endif
void do_btb_flush_fixups(void);
#endif /* !__ASSEMBLY__ */
diff --git a/arch/powerpc/kernel/security.c b/arch/powerpc/kernel/security.c
index 2d9c46f95e74..1fd1aabc1193 100644
--- a/arch/powerpc/kernel/security.c
+++ b/arch/powerpc/kernel/security.c
@@ -27,6 +27,10 @@ static enum count_cache_flush_type count_cache_flush_type = COUNT_CACHE_FLUSH_NO
bool barrier_nospec_enabled;
static bool no_nospec;
+static bool btb_flush_enabled;
+#ifdef CONFIG_PPC_FSL_BOOK3E
+static bool no_spectrev2;
+#endif
static void enable_barrier_nospec(bool enable)
{
@@ -102,6 +106,23 @@ static __init int barrier_nospec_debugfs_init(void)
device_initcall(barrier_nospec_debugfs_init);
#endif /* CONFIG_DEBUG_FS */
+#ifdef CONFIG_PPC_FSL_BOOK3E
+static int __init handle_nospectre_v2(char *p)
+{
+ no_spectrev2 = true;
+
+ return 0;
+}
+early_param("nospectre_v2", handle_nospectre_v2);
+void setup_spectre_v2(void)
+{
+ if (no_spectrev2)
+ do_btb_flush_fixups();
+ else
+ btb_flush_enabled = true;
+}
+#endif /* CONFIG_PPC_FSL_BOOK3E */
+
#ifdef CONFIG_PPC_BOOK3S_64
ssize_t cpu_show_meltdown(struct device *dev, struct device_attribute *attr, char *buf)
{