| Message ID | 20180508070517.947-2-clg@kaod.org (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | d2b04b0c78881ef1c051cc3a4a2c61b7bf91aa53 |
| Headers | show |
| Series | powerpc/xive: add support for H_INT_RESET | expand |
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@kaod.org> Series applied to powerpc next, thanks. https://git.kernel.org/powerpc/c/d2b04b0c78881ef1c051cc3a4a2c61 cheers
diff --git a/arch/powerpc/kernel/machine_kexec_64.c b/arch/powerpc/kernel/machine_kexec_64.c index 1044bf15d5ed..a0f6f45005bd 100644 --- a/arch/powerpc/kernel/machine_kexec_64.c +++ b/arch/powerpc/kernel/machine_kexec_64.c @@ -231,16 +231,16 @@ static void kexec_prepare_cpus(void) /* we are sure every CPU has IRQs off at this point */ kexec_all_irq_disabled = 1; - /* after we tell the others to go down */ - if (ppc_md.kexec_cpu_down) - ppc_md.kexec_cpu_down(0, 0); - /* * Before removing MMU mappings make sure all CPUs have entered real * mode: */ kexec_prepare_cpus_wait(KEXEC_STATE_REAL_MODE); + /* after we tell the others to go down */ + if (ppc_md.kexec_cpu_down) + ppc_md.kexec_cpu_down(0, 0); + put_cpu(); }
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@kaod.org> --- arch/powerpc/kernel/machine_kexec_64.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)