Messages in this thread | | | Subject | Re: [PATCH v2 1/2] bus: arm-ccn: Fix use of smp_processor_id() in preemptible context | From | Marc Zyngier <> | Date | Wed, 4 Oct 2017 13:32:11 +0100 |
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On 04/10/17 12:26, Pawel Moll wrote: > On Tue, 2017-10-03 at 18:14 +0100, Marc Zyngier wrote: >> Booting a DEBUG_PREEMPT enabled kernel on a CCN-based system >> results in the following splat: >> >> [...] >> arm-ccn e8000000.ccn: No access to interrupts, using timer. >> BUG: using smp_processor_id() in preemptible [00000000] code: >> swapper/0/1 >> caller is debug_smp_processor_id+0x1c/0x28 >> CPU: 1 PID: 1 Comm: swapper/0 Not tainted 4.13.0 #6111 >> Hardware name: AMD Seattle/Seattle, BIOS 17:08:23 Jun 26 2017 >> Call trace: >> [<ffff000008089e78>] dump_backtrace+0x0/0x278 >> [<ffff00000808a22c>] show_stack+0x24/0x30 >> [<ffff000008bc3bc4>] dump_stack+0x8c/0xb0 >> [<ffff00000852b534>] check_preemption_disabled+0xfc/0x100 >> [<ffff00000852b554>] debug_smp_processor_id+0x1c/0x28 >> [<ffff000008551bd8>] arm_ccn_probe+0x358/0x4f0 >> [...] >> >> as we use smp_processor_id() in the wrong context. >> >> Turn this into a get_cpu()/put_cpu() that extends over the CPU >> hotplug >> registration, making sure that we don't race against a CPU down >> operation. >> >> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> > > Acked-by: Pawel Moll <pawel.moll@arm.com> > > I assume you'll get this merged yourself? Or do you want me to relay > the CCN one (I've got a couple of other small changes to the driver in > the queue).
I'd rather you take care of it if you already have a queue of patches. Otherwise, I'll bundle the two patches and ask the armsoc folks to do something with them.
Thanks,
M. -- Jazz is not dead. It just smells funny...
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