From: linux@arm.linux.org.uk (Russell King - ARM Linux)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH] [ARM] Unconditional call to smp_cross_call on UP crashes
Date: Thu, 24 May 2012 17:17:33 +0100 [thread overview]
Message-ID: <20120524161733.GF6908@n2100.arm.linux.org.uk> (raw)
In-Reply-To: <1337889024-10416-1-git-send-email-panto@antoniou-consulting.com>
On Thu, May 24, 2012 at 07:50:24PM +0000, Pantelis Antoniou wrote:
> omap2plus_defconfig builds with SMP & SMP_ON_UP set.
> On beagle (which is UP) is_smp() returns false and we don't call
> smp_init_cpus which in turn does not initialize smp_cross_call which
> remains NULL.
>
> When issuing a reboot we OOPS with a NULL dereference on stop smp_call.
I've been wondering whether we should make smp_cross_call() a no-op instead
by default, rather than a NULL pointer.
Alternatively, if may be well worth changing this to do:
if (!cpumask_empty(&mask))
smp_cross_call(&mask, IPI_CPU_STOP);
instead, so we avoid calling smp_cross_call() when we're on a SMP system
with only one CPU online. I like this approach better because it removes
a potential call into platform code which is inappropriate.
next prev parent reply other threads:[~2012-05-24 16:17 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-05-24 19:50 [PATCH] [ARM] Unconditional call to smp_cross_call on UP crashes Pantelis Antoniou
2012-05-24 16:17 ` Russell King - ARM Linux [this message]
2012-05-24 16:55 ` Pantelis Antoniou
2012-05-24 17:15 ` Russell King - ARM Linux
-- strict thread matches above, loose matches on Subject: below --
2012-05-24 19:40 Pantelis Antoniou
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