From: Luis Chamberlain <mcgrof@kernel.org>
To: Prarit Bhargava <prarit@redhat.com>,
David Hildenbrand <david@redhat.com>
Cc: pmladek@suse.com, Petr Pavlu <petr.pavlu@suse.com>,
linux-modules@vger.kernel.org, linux-kernel@vger.kernel.org,
mcgrof@kernel.org
Subject: Re: [PATCH v2 2/2] module: Merge same-name module load requests
Date: Fri, 11 Nov 2022 17:47:17 -0800 [thread overview]
Message-ID: <Y277Jb9i2VeXQoTL@bombadil.infradead.org> (raw)
In-Reply-To: <d0bc50e3-0e42-311b-20ed-7538bb918c5b@suse.com>
On Wed, Oct 19, 2022 at 02:00:55PM +0200, Petr Pavlu wrote:
> On 10/18/22 20:33, Luis Chamberlain wrote:
> > On Sat, Oct 15, 2022 at 11:27:10AM +0200, Petr Pavlu wrote:
> >> The patch does address a regression observed after commit 6e6de3dee51a
> >> ("kernel/module.c: Only return -EEXIST for modules that have finished
> >> loading"). I guess it can have a Fixes tag added to the patch.
> >>
> >> I think it is hard to split this patch into parts because the implemented
> >> "optimization" is the fix.
> >
> > git describe --contains 6e6de3dee51a
> > v5.3-rc1~38^2~6
> >
> > I'm a bit torn about this situation. Reverting 6e6de3dee51a would be the
> > right thing to do, but without it, it still leaves the issue reported
> > by Prarit Bhargava. We need a way to resolve the issue on stable and
> > then your optimizations can be applied on top.
>
> Simpler could be to do the following:
>
> diff --git a/kernel/module/main.c b/kernel/module/main.c
> index d02d39c7174e..0302ac387e93 100644
> --- a/kernel/module/main.c
> +++ b/kernel/module/main.c
> @@ -2386,7 +2386,8 @@ static bool finished_loading(const char *name)
> sched_annotate_sleep();
> mutex_lock(&module_mutex);
> mod = find_module_all(name, strlen(name), true);
> - ret = !mod || mod->state == MODULE_STATE_LIVE;
> + ret = !mod || mod->state == MODULE_STATE_LIVE
> + || mod->state == MODULE_STATE_GOING;
> mutex_unlock(&module_mutex);
>
> return ret;
> @@ -2566,7 +2567,8 @@ static int add_unformed_module(struct module *mod)
> mutex_lock(&module_mutex);
> old = find_module_all(mod->name, strlen(mod->name), true);
> if (old != NULL) {
> - if (old->state != MODULE_STATE_LIVE) {
> + if (old->state == MODULE_STATE_COMING
> + || old->state == MODULE_STATE_UNFORMED) {
> /* Wait in case it fails to load. */
> mutex_unlock(&module_mutex);
> err = wait_event_interruptible(module_wq,
> @@ -2575,7 +2577,7 @@ static int add_unformed_module(struct module *mod)
> goto out_unlocked;
> goto again;
> }
> - err = -EEXIST;
> + err = old->state != MODULE_STATE_LIVE ? -EBUSY : -EEXIST;
> goto out;
> }
> mod_update_bounds(mod);
Prarit, can you verify this still does not break the issue you reported?
David, does this also fix your issue?
Petr, does this solve *any* of your issues? Can you also send a proper
patch with a commit log once we get confirmation of the tests.
I've been nose diving onto all of these 3 issues now and I have some
ideas of how to split this crap better and save even more memory on
bootup due to these stupid multiple requests. I want to first solve this
regression.
Luis
next prev parent reply other threads:[~2022-11-12 1:47 UTC|newest]
Thread overview: 43+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-09-19 12:32 [PATCH v2 0/2] module: Merge same-name module load requests Petr Pavlu
2022-09-19 12:32 ` [PATCH v2 1/2] module: Correct wake up of module_wq Petr Pavlu
2022-09-30 20:22 ` Luis Chamberlain
2022-10-14 8:40 ` Petr Mladek
2022-09-19 12:32 ` [PATCH v2 2/2] module: Merge same-name module load requests Petr Pavlu
2022-09-30 20:30 ` Luis Chamberlain
2022-10-15 9:27 ` Petr Pavlu
2022-10-18 18:33 ` Luis Chamberlain
2022-10-18 19:19 ` Prarit Bhargava
2022-10-18 19:53 ` Prarit Bhargava
2022-10-20 7:19 ` Petr Mladek
2022-10-24 13:22 ` Prarit Bhargava
2022-10-24 17:08 ` Luis Chamberlain
2022-10-24 12:37 ` Petr Pavlu
2022-10-24 14:00 ` Prarit Bhargava
2022-11-13 16:44 ` Petr Pavlu
2022-10-19 12:00 ` Petr Pavlu
2022-10-20 7:03 ` Petr Mladek
2022-10-24 17:53 ` Luis Chamberlain
2022-11-12 1:47 ` Luis Chamberlain [this message]
2022-11-14 8:57 ` David Hildenbrand
2022-11-14 15:38 ` Luis Chamberlain
2022-11-14 15:45 ` David Hildenbrand
2022-11-15 19:29 ` Luis Chamberlain
2022-11-16 16:03 ` Prarit Bhargava
2022-11-21 16:00 ` Petr Pavlu
2022-11-21 19:03 ` Luis Chamberlain
2022-11-21 19:50 ` David Hildenbrand
2022-11-21 20:27 ` Luis Chamberlain
2022-11-22 13:59 ` Petr Pavlu
2022-11-22 17:58 ` Luis Chamberlain
2022-11-16 16:04 ` David Hildenbrand
2022-11-18 17:32 ` David Hildenbrand
2022-11-28 16:29 ` Prarit Bhargava
2022-11-29 13:13 ` Petr Pavlu
2022-12-02 16:36 ` Petr Mladek
2022-12-06 12:31 ` Prarit Bhargava
2022-12-07 13:23 ` Petr Pavlu
2022-12-04 19:58 ` Prarit Bhargava
2022-10-14 7:54 ` David Hildenbrand
2022-10-15 9:49 ` Petr Pavlu
2022-10-14 13:52 ` Petr Mladek
2022-10-16 12:25 ` Petr Pavlu
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