Messages in this thread | | | Date | Tue, 24 Nov 2015 08:52:06 -0800 | From | "Paul E. McKenney" <> | Subject | Re: suspicious RCU usage on 4.4-rc2 ARM platform |
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On Tue, Nov 24, 2015 at 04:27:50PM +0000, Juri Lelli wrote: > Hi Paul, > > I'm hitting these splats while running simple hotplug tests on an ARM > TC2 platform. The following seems to cure it, but I don't think it never > made it to mainline: > > https://lkml.org/lkml/2015/5/12/892 > > Any reason why?
If I remember correctly, it could result in failures on some ARM processors. The problem was that this patch assumes that the CPU caches remain active throughout, when in fact they can be disabled at an inconvenient time. As I understand it, this can result in other updates to that cache line being lost when the CPU is powered off.
RMK would know more.
Thanx, Paul
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