Re: [PATCH 3/3 v4] livepatch: old_name,number scheme in livepatch sysfs directory
From: Josh Poimboeuf <hidden>
Date: 2015-11-11 18:02:00
Also in:
lkml
On Wed, Nov 11, 2015 at 10:29:01AM -0600, Chris J Arges wrote:
The following directory structure will allow for cases when the same function name exists in a single object. /sys/kernel/livepatch/<patch>/<object>/<function,number> The number corresponds to the nth occurrence of the symbol name in kallsyms for the patched object. An example of patching multiple symbols can be found here: https://github.com/dynup/kpatch/issues/493
Instead of 'function,number' here and everywhere else, maybe 'function,sympos' would be a little clearer. Also, s/old_name/function/ in the patch subject to be consistent.
quoted hunk ↗ jump to hunk
Signed-off-by: Chris J Arges <redacted> --- Documentation/ABI/testing/sysfs-kernel-livepatch | 6 +++++- kernel/livepatch/core.c | 10 ++++++++-- 2 files changed, 13 insertions(+), 3 deletions(-)diff --git a/Documentation/ABI/testing/sysfs-kernel-livepatch b/Documentation/ABI/testing/sysfs-kernel-livepatch index 5bf42a8..21b6bc1 100644 --- a/Documentation/ABI/testing/sysfs-kernel-livepatch +++ b/Documentation/ABI/testing/sysfs-kernel-livepatch@@ -33,7 +33,7 @@ Description: The object directory contains subdirectories for each function that is patched within the object. -What: /sys/kernel/livepatch/<patch>/<object>/<function> +What: /sys/kernel/livepatch/<patch>/<object>/<function,number> Date: Nov 2014 KernelVersion: 3.19.0 Contact: live-patching-u79uwXL29TY76Z2rM5mHXA@public.gmane.org@@ -41,4 +41,8 @@ Description: The function directory contains attributes regarding the properties and state of the patched function. + The directory name contains the patched function name and a + number corresponding to the nth occurrence of the symbol name + in kallsyms for the patched object. + There are currently no such attributes.diff --git a/kernel/livepatch/core.c b/kernel/livepatch/core.c index 4eb8691..ed2cbbf 100644 --- a/kernel/livepatch/core.c +++ b/kernel/livepatch/core.c@@ -542,7 +542,7 @@ EXPORT_SYMBOL_GPL(klp_enable_patch); * /sys/kernel/livepatch/<patch> * /sys/kernel/livepatch/<patch>/enabled * /sys/kernel/livepatch/<patch>/<object> - * /sys/kernel/livepatch/<patch>/<object>/<func> + * /sys/kernel/livepatch/<patch>/<object>/<func,number> */ static ssize_t enabled_store(struct kobject *kobj, struct kobj_attribute *attr,@@ -687,8 +687,14 @@ static int klp_init_func(struct klp_object *obj, struct klp_func *func) INIT_LIST_HEAD(&func->stack_node); func->state = KLP_DISABLED; + /* The format for the sysfs directory is <func,number> where number is + * the occurrence of this symbol in kallsyms. If the user selects 0 for
... of this symbol in kallsyms *for the patched object*.
+ * old_sympos, then 1 will be used since a unique symbol will be the + * first occurrence. + */ return kobject_init_and_add(&func->kobj, &klp_ktype_func, - &obj->kobj, "%s", func->old_name); + &obj->kobj, "%s,%lu", func->old_name, + func->old_sympos ? func->old_sympos : 1); } /* parts of the initialization that is done only when the object is loaded */ -- 1.9.1
-- Josh