From: Miroslav Benes <mbenes@suse.cz>
To: Seth Jennings <sjenning@redhat.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>,
Jiri Kosina <jkosina@suse.cz>, Vojtech Pavlik <vojtech@suse.cz>,
Steven Rostedt <rostedt@goodmis.org>,
Petr Mladek <pmladek@suse.cz>,
Christoph Hellwig <hch@infradead.org>,
Greg KH <gregkh@linuxfoundation.org>,
Andy Lutomirski <luto@amacapital.net>,
Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>,
live-patching@vger.kernel.org, x86@kernel.org, kpatch@redhat.com,
linux-kernel@vger.kernel.org
Subject: Re: [PATCHv2 2/3] kernel: add support for live patching
Date: Wed, 19 Nov 2014 16:27:39 +0100 (CET) [thread overview]
Message-ID: <alpine.LNX.2.00.1411191615000.5471@pobox.suse.cz> (raw)
In-Reply-To: <1416187764-3341-3-git-send-email-sjenning@redhat.com>
Hi,
during rewriting our code I came across few more things. See below.
On Sun, 16 Nov 2014, Seth Jennings wrote:
[...]
> +/******************************
> + * module notifier
> + *****************************/
> +
> +static void lpc_module_notify_coming(struct module *pmod,
> + struct lpc_object *obj)
> +{
> + struct module *mod = obj->mod;
> + int ret;
> +
> + pr_notice("applying patch '%s' to loading module '%s'\n",
> + mod->name, pmod->name);
This looks strange. I guess the arguments should be swapped.
> + obj->mod = mod;
And this is redundant.
> + ret = lpc_enable_object(pmod, obj);
> + if (ret)
> + pr_warn("failed to apply patch '%s' to module '%s' (%d)\n",
> + pmod->name, mod->name, ret);
> +}
> +
> +static void lpc_module_notify_going(struct module *pmod,
> + struct lpc_object *obj)
> +{
> + struct module *mod = obj->mod;
> + int ret;
> +
> + pr_notice("reverting patch '%s' on unloading module '%s'\n",
> + pmod->name, mod->name);
> + ret = lpc_disable_object(obj);
> + if (ret)
> + pr_warn("failed to revert patch '%s' on module '%s' (%d)\n",
> + pmod->name, mod->name, ret);
> + obj->mod = NULL;
> +}
> +
> +static int lpc_module_notify(struct notifier_block *nb, unsigned long action,
> + void *data)
> +{
> + struct module *mod = data;
> + struct lpc_patch *patch;
> + struct lpc_object *obj;
> +
> + mutex_lock(&lpc_mutex);
> +
> + if (action != MODULE_STATE_COMING && action != MODULE_STATE_GOING)
> + goto out;
> +
> + list_for_each_entry(patch, &lpc_patches, list) {
> + if (patch->state == LPC_DISABLED)
> + continue;
> + list_for_each_entry(obj, &patch->objs, list) {
> + if (strcmp(obj->name, mod->name))
> + continue;
> + if (action == MODULE_STATE_COMING) {
> + obj->mod = mod;
> + lpc_module_notify_coming(patch->mod, obj);
> + } else /* MODULE_STATE_GOING */
> + lpc_module_notify_going(patch->mod, obj);
> + break;
> + }
> + }
> +out:
> + mutex_unlock(&lpc_mutex);
> + return 0;
> +}
[...]
> +static struct lpc_object *lpc_create_object(struct kobject *root,
> + struct lp_object *userobj)
> +{
> + struct lpc_object *obj;
> + int ret;
> +
> + /* alloc */
> + obj = kzalloc(sizeof(*obj), GFP_KERNEL);
> + if (!obj)
> + return NULL;
> +
> + /* init */
> + INIT_LIST_HEAD(&obj->list);
> + obj->name = userobj->name;
> + obj->relocs = userobj->relocs;
> + obj->state = LPC_DISABLED;
> + /* obj->mod set by lpc_object_module_get() */
> + INIT_LIST_HEAD(&obj->funcs);
There is nothing like lpc_object_module_get() in the code. Did you mean
lpc_find_object_module()?
Thank you,
--
Miroslav Benes
SUSE Labs
next prev parent reply other threads:[~2014-11-19 15:27 UTC|newest]
Thread overview: 26+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-11-17 1:29 [PATCHv2 0/3] Kernel Live Patching Seth Jennings
2014-11-17 1:29 ` [PATCHv2 1/3] kernel: add TAINT_LIVEPATCH Seth Jennings
2014-11-17 1:29 ` [PATCHv2 2/3] kernel: add support for live patching Seth Jennings
2014-11-17 18:45 ` Greg KH
2014-11-17 19:13 ` Seth Jennings
2014-11-18 14:11 ` Miroslav Benes
2014-11-18 14:26 ` Seth Jennings
2014-11-18 14:45 ` Miroslav Benes
2014-11-19 20:34 ` Seth Jennings
2014-11-20 13:22 ` Miroslav Benes
2014-11-19 15:27 ` Miroslav Benes [this message]
2014-11-19 16:05 ` Seth Jennings
2014-11-20 13:10 ` Miroslav Benes
2014-11-20 17:35 ` Josh Poimboeuf
2014-11-20 19:56 ` Seth Jennings
2014-11-21 14:41 ` Miroslav Benes
2014-11-21 14:38 ` Miroslav Benes
2014-11-20 15:19 ` Josh Poimboeuf
2014-11-20 16:48 ` Seth Jennings
2014-11-17 1:29 ` [PATCHv2 3/3] kernel: add sysfs documentation " Seth Jennings
2014-11-17 18:50 ` Greg KH
2014-11-17 5:33 ` [PATCHv2 0/3] Kernel Live Patching Masami Hiramatsu
2014-11-17 13:16 ` Steven Rostedt
2014-11-17 14:54 ` Seth Jennings
2014-11-18 14:23 ` Jiri Slaby
2014-11-18 14:42 ` Seth Jennings
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