From 1d5cc0de3be2306f38a378fd4fbc235abb12e0ed Mon Sep 17 00:00:00 2001
From: qjl21 <18810075699@163.com>
Date: Sat, 16 May 2026 18:15:48 +0800
Subject: [PATCH 1/2]   kpatch: add support for CONFIG_LIVEPATCH_WO_FTRACE on
 openEuler 6.6

  openEuler 6.6 introduces ftrace-less livepatch via the kernel config
  CONFIG_LIVEPATCH_WO_FTRACE=y.  When this option is enabled,
  CONFIG_LIVEPATCH_FTRACE is not set and the kernel applies live patches
  without relying on ftrace trampolines.

  Two changes are required to handle this configuration:

  kpatch-build: detect CONFIG_LIVEPATCH_WO_FTRACE=y in the target kernel
  config and automatically export NO_PROFILING_CALLS=1, which suppresses
  the ftrace-based profiling instrumentation that is incompatible with
  ftrace-less livepatch.

  livepatch-patch-hook.c: introduce the HAVE_WO_FTRACE_ENABLE helper macro
  when CONFIG_LIVEPATCH_WO_FTRACE is defined, and guard the
  klp_enable_patch() call with it so the correct activation path is
  selected at compile time.

  Signed-off-by: qujingling <18810075699@163.com>
---
 kmod/patch/livepatch-patch-hook.c | 7 +++++++
 kpatch-build/kpatch-build         | 2 ++
 2 files changed, 9 insertions(+)

diff --git a/kmod/patch/livepatch-patch-hook.c b/kmod/patch/livepatch-patch-hook.c
index 3d13ab97e..8878a4bfc 100644
--- a/kmod/patch/livepatch-patch-hook.c
+++ b/kmod/patch/livepatch-patch-hook.c
@@ -86,6 +86,11 @@
 #define KLP_REPLACE_ENABLE true
 #endif
 
+
+#ifdef CONFIG_LIVEPATCH_WO_FTRACE
+#define HAVE_WO_FTRACE_ENABLE
+#endif
+
 /*
  * There are quite a few similar structures at play in this file:
  * - livepatch.h structs prefixed with klp_*
@@ -576,6 +581,7 @@ static int __init patch_init(void)
 	}
 #endif
 
+#if defined(HAVE_WO_FTRACE_ENABLE)
 	ret = klp_enable_patch(lpatch);
 	if (ret) {
 #ifndef HAVE_SIMPLE_ENABLE
@@ -584,6 +590,7 @@ static int __init patch_init(void)
 		patch_free_livepatch(lpatch);
 		return ret;
 	}
+#endif
 
 	return 0;
 out:
diff --git a/kpatch-build/kpatch-build b/kpatch-build/kpatch-build
index 57c3f7265..a48fe3697 100755
--- a/kpatch-build/kpatch-build
+++ b/kpatch-build/kpatch-build
@@ -1232,6 +1232,8 @@ else
 	KBUILD_EXTRA_SYMBOLS="$SYMVERSFILE"
 fi
 
+grep -q "CONFIG_LIVEPATCH_WO_FTRACE=y" "$CONFIGFILE" && export NO_PROFILING_CALLS=1
+
 # unsupported kernel option checking
 [[ -n "$CONFIG_DEBUG_INFO_SPLIT" ]] && die "kernel option 'CONFIG_DEBUG_INFO_SPLIT' not supported"
 [[ -n "$CONFIG_GCC_PLUGIN_LATENT_ENTROPY" ]] && die "kernel option 'CONFIG_GCC_PLUGIN_LATENT_ENTROPY' not supported"

From eeffe76e041679410a7727e164e983407afed5c6 Mon Sep 17 00:00:00 2001
From: qjl21 <18810075699@163.com>
Date: Sat, 16 May 2026 18:14:54 +0800
Subject: [PATCH 2/2]   kpatch-build: skip
 CONFIG_LIVEPATCH_PER_TASK_CONSISTENCY check on kernel >= 6.6

  CONFIG_LIVEPATCH_PER_TASK_CONSISTENCY was removed in the 6.6 kernel.
  On openEuler 6.6, the per-task consistency model is no longer a
  separate Kconfig symbol; the kernel instead uses
  CONFIG_LIVEPATCH_STOP_MACHINE_CONSISTENCY and
  CONFIG_LIVEPATCH_WO_FTRACE to describe its livepatch mechanism.

  The existing check unconditionally fails when building against an
  openEuler 6.6 kernel because the config option simply does not appear
  in the .config file, even though the kernel is correctly configured
  for live patching.

  Guard the check with a kernel version comparison so that it only fires
  on kernels older than 6.6, where CONFIG_LIVEPATCH_PER_TASK_CONSISTENCY
  is still the expected indicator of a supported livepatch configuration.

  Signed-off-by: qujingling <18810075699@163.com>
---
 kpatch-build/kpatch-build | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kpatch-build/kpatch-build b/kpatch-build/kpatch-build
index a48fe3697..9d54006e8 100755
--- a/kpatch-build/kpatch-build
+++ b/kpatch-build/kpatch-build
@@ -1194,7 +1194,7 @@ trace_off "reading .config"
 source "$CONFIGFILE"
 trace_on
 
-[[ "$DISTRO" = openEuler ]] && [[ -z "$CONFIG_LIVEPATCH_PER_TASK_CONSISTENCY" ]] && \
+[[ "$DISTRO" = openEuler ]] && ! kernel_version_gte 6.6.0 && [[ -z "$CONFIG_LIVEPATCH_PER_TASK_CONSISTENCY" ]] && \
 	die "openEuler kernel doesn't have 'CONFIG_LIVEPATCH_PER_TASK_CONSISTENCY' enabled"
 
 [[ -z "$CONFIG_DEBUG_INFO" ]] && die "kernel doesn't have 'CONFIG_DEBUG_INFO' enabled"