[v2, 1/4] powerpc/64/kexec: fix race in kexec when XIVE is shutdown

[Michael Ellerman]

On Tue, 2018-05-08 at 07:05:14 UTC, =?utf-8?q?C=C3=A9dric_Le_Goater?= wrote:
> The kexec_state KEXEC_STATE_IRQS_OFF barrier is reached by all
> secondary CPUs before the kexec_cpu_down() operation is called on
> secondaries. This can raise conflicts and provoque errors in the XIVE
> hcalls when XIVE is shutdown with H_INT_RESET on the primary CPU.
> 
> To synchronize the kexec_cpu_down() operations and make sure the
> secondaries have completed their task before the primary starts doing
> the same, let's move the primary kexec_cpu_down() after the
> KEXEC_STATE_REAL_MODE barrier.
> 
> This change of the ending sequence of kexec is mostly useful on the
> pseries platform but it impacts also the powernv, ps3 and 85xx
> platforms. powernv can be easily tested and fixed but some caution is
> required for the other two.
> 
> Signed-off-by: Cédric Le Goater <clg at kaod.org>

Series applied to powerpc next, thanks.

https://git.kernel.org/powerpc/c/d2b04b0c78881ef1c051cc3a4a2c61

cheers