[CFT] Always enable SMP mode on MP capable CPUs

Tony Lindgren tony at atomide.com
Thu May 25 10:10:00 PDT 2017


* Russell King - ARM Linux <linux at armlinux.org.uk> [170525 10:00]:
> On Thu, May 25, 2017 at 09:15:19AM -0700, Florian Fainelli wrote:
> > On 05/18/2017 03:52 AM, Russell King - ARM Linux wrote:
> > > As a result of a recent bug report, it has been found that certain CPUs
> > > must always have SMP mode enabled in order for the caches to work.
> > > 
> > > Remove the conditional on setting the SMP bit(s).
> > > 
> > > Signed-off-by: Russell King <rmk+kernel at armlinux.org.uk>
> > > ---
> > > This needs to be tested on:
> > > 
> > > - Cortex A5MP
> > > - Cortex A9MP
> > > - Cortex R7MP
> > > - Cortex A7MP
> > > - Cortex A12MP
> > > - Cortex A15MP
> > > - Cortex A17MP
> > > - Brahma B15
> > 
> > Sorry just saw this, what kind of test do you want me to run on B15?
> > Should I build a !SMP kernel, or force a SMP kernel with maxcpus=1?
> 
> What I'm after is testing on any single-core systems with these SMP
> capable cores.  If the core never appears in a single-core configuration,
> then please let me know so it can be crossed off the list.
> 
> With the bug that crept in fixed (as pointed out by Tony) there is no
> difference for kernels built with SMP enabled and detected as a SMP
> capable CPU.

At least am437x needs to be tested as it's UP with some quirks.

Regards,

Tony



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