Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 34 insertions, 0 deletions

diff --git a/arch/s390/kernel/rethook.c b/arch/s390/kernel/rethook.c
new file mode 100644
index 0000000000..af10e6bdd3
--- /dev/null
+++ b/arch/s390/kernel/rethook.c
@@ -0,0 +1,34 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+#include <linux/rethook.h>
+#include <linux/kprobes.h>
+#include "rethook.h"
+
+void arch_rethook_prepare(struct rethook_node *rh, struct pt_regs *regs, bool mcount)
+{
+	rh->ret_addr = regs->gprs[14];
+	rh->frame = regs->gprs[15];
+
+	/* Replace the return addr with trampoline addr */
+	regs->gprs[14] = (unsigned long)&arch_rethook_trampoline;
+}
+NOKPROBE_SYMBOL(arch_rethook_prepare);
+
+void arch_rethook_fixup_return(struct pt_regs *regs,
+			       unsigned long correct_ret_addr)
+{
+	/* Replace fake return address with real one. */
+	regs->gprs[14] = correct_ret_addr;
+}
+NOKPROBE_SYMBOL(arch_rethook_fixup_return);
+
+/*
+ * Called from arch_rethook_trampoline
+ */
+unsigned long arch_rethook_trampoline_callback(struct pt_regs *regs)
+{
+	return rethook_trampoline_handler(regs, regs->gprs[15]);
+}
+NOKPROBE_SYMBOL(arch_rethook_trampoline_callback);
+
+/* assembler function that handles the rethook must not be probed itself */
+NOKPROBE_SYMBOL(arch_rethook_trampoline);