4 files changed, 42 insertions, 4 deletions

diff --git a/arch/riscv/errata/Makefile b/arch/riscv/errata/Makefile
index 8a2739485123..bc6c77ba837d 100644
--- a/arch/riscv/errata/Makefile
+++ b/arch/riscv/errata/Makefile
@@ -1,5 +1,15 @@
 ifdef CONFIG_RELOCATABLE
-KBUILD_CFLAGS += -fno-pie
+# We can't use PIC/PIE when handling early-boot errata parsing, as the kernel
+# doesn't have a GOT setup at that point.  So instead just use medany: it's
+# usually position-independent, so it should be good enough for the errata
+# handling.
+KBUILD_CFLAGS += -fno-pie -mcmodel=medany
+endif
+
+ifdef CONFIG_RISCV_ALTERNATIVE_EARLY
+ifdef CONFIG_FORTIFY_SOURCE
+KBUILD_CFLAGS += -D__NO_FORTIFY
+endif
 endif
 
 obj-$(CONFIG_ERRATA_ANDES) += andes/
diff --git a/arch/riscv/errata/andes/errata.c b/arch/riscv/errata/andes/errata.c
index fc1a34faa5f3..dcc9d1ee5ffd 100644
--- a/arch/riscv/errata/andes/errata.c
+++ b/arch/riscv/errata/andes/errata.c
@@ -13,7 +13,7 @@
 #include <asm/alternative.h>
 #include <asm/cacheflush.h>
 #include <asm/errata_list.h>
-#include <asm/patch.h>
+#include <asm/text-patching.h>
 #include <asm/processor.h>
 #include <asm/sbi.h>
 #include <asm/vendorid_list.h>
diff --git a/arch/riscv/errata/sifive/errata.c b/arch/riscv/errata/sifive/errata.c
index cea3b96ade11..38aac2c47845 100644
--- a/arch/riscv/errata/sifive/errata.c
+++ b/arch/riscv/errata/sifive/errata.c
@@ -8,7 +8,7 @@
 #include <linux/module.h>
 #include <linux/string.h>
 #include <linux/bug.h>
-#include <asm/patch.h>
+#include <asm/text-patching.h>
 #include <asm/alternative.h>
 #include <asm/vendorid_list.h>
 #include <asm/errata_list.h>
diff --git a/arch/riscv/errata/thead/errata.c b/arch/riscv/errata/thead/errata.c
index f5120e07c318..0b942183f708 100644
--- a/arch/riscv/errata/thead/errata.c
+++ b/arch/riscv/errata/thead/errata.c
@@ -10,13 +10,14 @@
 #include <linux/string.h>
 #include <linux/uaccess.h>
 #include <asm/alternative.h>
+#include <asm/bugs.h>
 #include <asm/cacheflush.h>
 #include <asm/cpufeature.h>
 #include <asm/dma-noncoherent.h>
 #include <asm/errata_list.h>
 #include <asm/hwprobe.h>
 #include <asm/io.h>
-#include <asm/patch.h>
+#include <asm/text-patching.h>
 #include <asm/vendorid_list.h>
 #include <asm/vendor_extensions.h>
 
@@ -142,6 +143,31 @@ static bool errata_probe_pmu(unsigned int stage,
 	return true;
 }
 
+static bool errata_probe_ghostwrite(unsigned int stage,
+				    unsigned long arch_id, unsigned long impid)
+{
+	if (!IS_ENABLED(CONFIG_ERRATA_THEAD_GHOSTWRITE))
+		return false;
+
+	/*
+	 * target-c9xx cores report arch_id and impid as 0
+	 *
+	 * While ghostwrite may not affect all c9xx cores that implement
+	 * xtheadvector, there is no futher granularity than c9xx. Assume
+	 * vulnerable for this entire class of processors when xtheadvector is
+	 * enabled.
+	 */
+	if (arch_id != 0 || impid != 0)
+		return false;
+
+	if (stage != RISCV_ALTERNATIVES_EARLY_BOOT)
+		return false;
+
+	ghostwrite_set_vulnerable();
+
+	return true;
+}
+
 static u32 thead_errata_probe(unsigned int stage,
 			      unsigned long archid, unsigned long impid)
 {
@@ -155,6 +181,8 @@ static u32 thead_errata_probe(unsigned int stage,
 	if (errata_probe_pmu(stage, archid, impid))
 		cpu_req_errata |= BIT(ERRATA_THEAD_PMU);
 
+	errata_probe_ghostwrite(stage, archid, impid);
+
 	return cpu_req_errata;
 }