[PATCH v2 1/2] livepatch: add sysfs entry "patched" for each klp_object
From: Song Liu <song@kernel.org>
Date: 2022-08-02 01:09:16
Subsystem:
live patching, the rest · Maintainers:
Josh Poimboeuf, Jiri Kosina, Miroslav Benes, Petr Mladek, Linus Torvalds
Add per klp_object sysfs entry "patched". It makes it easier to debug typos in the module name. Signed-off-by: Song Liu <song@kernel.org> --- I was debugging an issue that a livepatch appears to be attached, but actually not. It turns out that there is a mismatch in module name (abc-xyz vs. abc_xyz), klp_find_object_module failed to find the module. --- .../ABI/testing/sysfs-kernel-livepatch | 8 ++++++++ kernel/livepatch/core.c | 18 ++++++++++++++++++ 2 files changed, 26 insertions(+)
diff --git a/Documentation/ABI/testing/sysfs-kernel-livepatch b/Documentation/ABI/testing/sysfs-kernel-livepatch
index bea7bd5a1d5f..ebe39a3cea39 100644
--- a/Documentation/ABI/testing/sysfs-kernel-livepatch
+++ b/Documentation/ABI/testing/sysfs-kernel-livepatch@@ -55,6 +55,14 @@ Description: The object directory contains subdirectories for each function that is patched within the object. +What: /sys/kernel/livepatch/<patch>/<object>/patched +Date: August 2022 +KernelVersion: 6.0.0 +Contact: live-patching@vger.kernel.org +Description: + An attribute which indicates whether the object is currently + patched. + What: /sys/kernel/livepatch/<patch>/<object>/<function,sympos> Date: Nov 2014 KernelVersion: 3.19.0
diff --git a/kernel/livepatch/core.c b/kernel/livepatch/core.c
index bc475e62279d..67eb9f9168f3 100644
--- a/kernel/livepatch/core.c
+++ b/kernel/livepatch/core.c@@ -325,6 +325,7 @@ int klp_apply_section_relocs(struct module *pmod, Elf_Shdr *sechdrs, * /sys/kernel/livepatch/<patch>/transition * /sys/kernel/livepatch/<patch>/force * /sys/kernel/livepatch/<patch>/<object> + * /sys/kernel/livepatch/<patch>/<object>/patched * /sys/kernel/livepatch/<patch>/<object>/<function,sympos> */ static int __klp_disable_patch(struct klp_patch *patch);
@@ -431,6 +432,22 @@ static struct attribute *klp_patch_attrs[] = { }; ATTRIBUTE_GROUPS(klp_patch); +static ssize_t patched_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct klp_object *obj; + + obj = container_of(kobj, struct klp_object, kobj); + return sysfs_emit(buf, "%d\n", obj->patched); +} + +static struct kobj_attribute patched_kobj_attr = __ATTR_RO(patched); +static struct attribute *klp_object_attrs[] = { + &patched_kobj_attr.attr, + NULL, +}; +ATTRIBUTE_GROUPS(klp_object); + static void klp_free_object_dynamic(struct klp_object *obj) { kfree(obj->name);
@@ -576,6 +593,7 @@ static void klp_kobj_release_object(struct kobject *kobj) static struct kobj_type klp_ktype_object = { .release = klp_kobj_release_object, .sysfs_ops = &kobj_sysfs_ops, + .default_groups = klp_object_groups, }; static void klp_kobj_release_func(struct kobject *kobj)
--
2.30.2