From: Joe Perches <joe@perches.com>
To: Theodore Ts'o <tytso@mit.edu>,
Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux-next@vger.kernel.org, linux-mm@kvack.org,
linux-kernel@vger.kernel.org,
Martin Schwidefsky <schwidefsky@de.ibm.com>
Subject: Re: [BUG -next] "random: make /dev/urandom scalable for silly userspace programs" causes crash
Date: Thu, 28 Jul 2016 11:12:09 -0700 [thread overview]
Message-ID: <1469729529.3998.59.camel@perches.com> (raw)
In-Reply-To: <20160728034601.GC20032@thunk.org>
On Wed, 2016-07-27 at 23:46 -0400, Theodore Ts'o wrote:
> On Wed, Jul 27, 2016 at 09:14:00AM +0200, Heiko Carstens wrote:
> >
> > it looks like your patch "random: make /dev/urandom scalable for silly
> > userspace programs" within linux-next seems to be a bit broken:
> >
> > It causes this allocation failure and subsequent crash on s390 with fake
> > NUMA enabled
> Thanks for reporting this. This patch fixes things for you, yes?
trivia:
> diff --git a/drivers/char/random.c b/drivers/char/random.c
[]
> @@ -1668,13 +1668,12 @@ static int rand_initialize(void)
> #ifdef CONFIG_NUMA
> pool = kmalloc(num_nodes * sizeof(void *),
> GFP_KERNEL|__GFP_NOFAIL|__GFP_ZERO);
The __GFP_ZERO is unusual and this could use kcalloc instead.
> - for (i=0; i < num_nodes; i++) {
> + for_each_online_node(i) {
> crng = kmalloc_node(sizeof(struct crng_state),
> GFP_KERNEL | __GFP_NOFAIL, i);
> spin_lock_init(&crng->lock);
> crng_initialize(crng);
> pool[i] = crng;
> -
> }
> mb();
> crng_node_pool = pool;
--
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WARNING: multiple messages have this Message-ID (diff)
From: Joe Perches <joe@perches.com>
To: Theodore Ts'o <tytso@mit.edu>,
Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux-next@vger.kernel.org, linux-mm@kvack.org,
linux-kernel@vger.kernel.org,
Martin Schwidefsky <schwidefsky@de.ibm.com>
Subject: Re: [BUG -next] "random: make /dev/urandom scalable for silly userspace programs" causes crash
Date: Thu, 28 Jul 2016 11:12:09 -0700 [thread overview]
Message-ID: <1469729529.3998.59.camel@perches.com> (raw)
In-Reply-To: <20160728034601.GC20032@thunk.org>
On Wed, 2016-07-27 at 23:46 -0400, Theodore Ts'o wrote:
> On Wed, Jul 27, 2016 at 09:14:00AM +0200, Heiko Carstens wrote:
> >
> > it looks like your patch "random: make /dev/urandom scalable for silly
> > userspace programs" within linux-next seems to be a bit broken:
> >
> > It causes this allocation failure and subsequent crash on s390 with fake
> > NUMA enabled
> Thanks for reporting this. This patch fixes things for you, yes?
trivia:
> diff --git a/drivers/char/random.c b/drivers/char/random.c
[]
> @@ -1668,13 +1668,12 @@ static int rand_initialize(void)
> #ifdef CONFIG_NUMA
> pool = kmalloc(num_nodes * sizeof(void *),
> GFP_KERNEL|__GFP_NOFAIL|__GFP_ZERO);
The __GFP_ZERO is unusual and this could use kcalloc instead.
> - for (i=0; i < num_nodes; i++) {
> + for_each_online_node(i) {
> crng = kmalloc_node(sizeof(struct crng_state),
> GFP_KERNEL | __GFP_NOFAIL, i);
> spin_lock_init(&crng->lock);
> crng_initialize(crng);
> pool[i] = crng;
> -
> }
> mb();
> crng_node_pool = pool;
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
WARNING: multiple messages have this Message-ID (diff)
From: Joe Perches <joe@perches.com>
To: "Theodore Ts'o" <tytso@mit.edu>,
Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux-next@vger.kernel.org, linux-mm@kvack.org,
linux-kernel@vger.kernel.org,
Martin Schwidefsky <schwidefsky@de.ibm.com>
Subject: Re: [BUG -next] "random: make /dev/urandom scalable for silly userspace programs" causes crash
Date: Thu, 28 Jul 2016 11:12:09 -0700 [thread overview]
Message-ID: <1469729529.3998.59.camel@perches.com> (raw)
In-Reply-To: <20160728034601.GC20032@thunk.org>
On Wed, 2016-07-27 at 23:46 -0400, Theodore Ts'o wrote:
> On Wed, Jul 27, 2016 at 09:14:00AM +0200, Heiko Carstens wrote:
> >
> > it looks like your patch "random: make /dev/urandom scalable for silly
> > userspace programs" within linux-next seems to be a bit broken:
> >
> > It causes this allocation failure and subsequent crash on s390 with fake
> > NUMA enabled
> Thanks for reporting this. This patch fixes things for you, yes?
trivia:
> diff --git a/drivers/char/random.c b/drivers/char/random.c
[]
> @@ -1668,13 +1668,12 @@ static int rand_initialize(void)
> #ifdef CONFIG_NUMA
> pool = kmalloc(num_nodes * sizeof(void *),
> GFP_KERNEL|__GFP_NOFAIL|__GFP_ZERO);
The __GFP_ZERO is unusual and this could use kcalloc instead.
> - for (i=0; i < num_nodes; i++) {
> + for_each_online_node(i) {
> crng = kmalloc_node(sizeof(struct crng_state),
> GFP_KERNEL | __GFP_NOFAIL, i);
> spin_lock_init(&crng->lock);
> crng_initialize(crng);
> pool[i] = crng;
> -
> }
> mb();
> crng_node_pool = pool;
next prev parent reply other threads:[~2016-07-28 18:12 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-07-27 7:14 [BUG -next] "random: make /dev/urandom scalable for silly userspace programs" causes crash Heiko Carstens
2016-07-27 7:14 ` Heiko Carstens
2016-07-28 3:46 ` Theodore Ts'o
2016-07-28 3:46 ` Theodore Ts'o
2016-07-28 5:55 ` Heiko Carstens
2016-07-28 5:55 ` Heiko Carstens
2016-07-28 7:24 ` Heiko Carstens
2016-07-28 7:24 ` Heiko Carstens
2016-07-28 13:41 ` Theodore Ts'o
2016-07-28 13:41 ` Theodore Ts'o
2016-07-28 23:56 ` Tony Luck
2016-07-28 23:56 ` Tony Luck
2016-07-28 18:12 ` Joe Perches [this message]
2016-07-28 18:12 ` Joe Perches
2016-07-28 18:12 ` Joe Perches
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