Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753661AbbKBXAd (ORCPT ); Mon, 2 Nov 2015 18:00:33 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:48776 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751297AbbKBXAb (ORCPT ); Mon, 2 Nov 2015 18:00:31 -0500 From: Chris J Arges To: live-patching@vger.kernel.org Cc: jeyu@redhat.com, Chris J Arges , Josh Poimboeuf , Seth Jennings , Jiri Kosina , Vojtech Pavlik , linux-api@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v2] livepatch: old_name.number scheme in livepatch sysfs directory Date: Mon, 2 Nov 2015 16:59:41 -0600 Message-Id: <1446505187-28970-1-git-send-email-chris.j.arges@canonical.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <20151102203241.GF27488@treble.redhat.com> References: <20151102203241.GF27488@treble.redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3437 Lines: 106 The following directory structure will allow for cases when the same function name exists in a single object. /sys/kernel/livepatch/// The number corresponds to the nth occurrence of the symbol name in kallsyms for the patched object. An example of this issue is documented here: https://github.com/dynup/kpatch/issues/493 Signed-off-by: Chris J Arges --- Documentation/ABI/testing/sysfs-kernel-livepatch | 2 +- kernel/livepatch/core.c | 45 ++++++++++++++++++++++-- 2 files changed, 44 insertions(+), 3 deletions(-) diff --git a/Documentation/ABI/testing/sysfs-kernel-livepatch b/Documentation/ABI/testing/sysfs-kernel-livepatch index 5bf42a8..dcd36db 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/// +What: /sys/kernel/livepatch/// Date: Nov 2014 KernelVersion: 3.19.0 Contact: live-patching@vger.kernel.org diff --git a/kernel/livepatch/core.c b/kernel/livepatch/core.c index 6e53441..6bcf600 100644 --- a/kernel/livepatch/core.c +++ b/kernel/livepatch/core.c @@ -587,7 +587,7 @@ EXPORT_SYMBOL_GPL(klp_enable_patch); * /sys/kernel/livepatch/ * /sys/kernel/livepatch//enabled * /sys/kernel/livepatch// - * /sys/kernel/livepatch/// + * /sys/kernel/livepatch/// */ static ssize_t enabled_store(struct kobject *kobj, struct kobj_attribute *attr, @@ -727,13 +727,54 @@ static void klp_free_patch(struct klp_patch *patch) kobject_put(&patch->kobj); } +static int klp_get_func_pos_callback(void *data, const char *name, + struct module *mod, unsigned long addr) +{ + struct klp_find_arg *args = data; + + if ((mod && !args->objname) || (!mod && args->objname)) + return 0; + + if (strcmp(args->name, name)) + return 0; + + if (args->objname && strcmp(args->objname, mod->name)) + return 0; + + /* on address match, return 1 to break kallsyms_on_each_symbol loop */ + if (args->addr == addr) + return 1; + + /* if we don't match addr, count instance of named symbol */ + args->count++; + + return 0; +} + +static int klp_get_func_pos(struct klp_object *obj, struct klp_func *func) +{ + struct klp_find_arg args = { + .objname = obj->name, + .name = func->old_name, + .addr = func->old_addr, + .count = 0, + }; + + mutex_lock(&module_mutex); + kallsyms_on_each_symbol(klp_get_func_pos_callback, &args); + mutex_unlock(&module_mutex); + + return args.count; +} + static int klp_init_func(struct klp_object *obj, struct klp_func *func) { INIT_LIST_HEAD(&func->stack_node); func->state = KLP_DISABLED; return kobject_init_and_add(&func->kobj, &klp_ktype_func, - &obj->kobj, "%s", func->old_name); + &obj->kobj, "%s,%d", func->old_name, + klp_get_func_pos(obj, func)); } /* parts of the initialization that is done only when the object is loaded */ -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/