disable_nonboot_cpus() is not safe to use when doing machine_down(),
because it relies on freeze_secondary_cpus() which in turn is
a suspend/resume related freeze and could abort if the logic detects any
pending activities that can prevent finishing the offlining process.
Beside disable_nonboot_cpus() is dependent on CONFIG_PM_SLEEP_SMP which
is an othogonal config to rely on to ensure this function works
correctly.
Use `reboot_cpu` variable instead of hardcoding 0 as the reboot cpu.
Signed-off-by: Qais Yousef <[email protected]>
CC: Catalin Marinas <[email protected]>
CC: Will Deacon <[email protected]>
CC: [email protected]
CC: [email protected]
---
arch/arm64/kernel/process.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c
index bbb0f0c145f6..b33b415fb32e 100644
--- a/arch/arm64/kernel/process.c
+++ b/arch/arm64/kernel/process.c
@@ -141,11 +141,11 @@ void arch_cpu_idle_dead(void)
* to execute e.g. a RAM-based pin loop is not sufficient. This allows the
* kexec'd kernel to use any and all RAM as it sees fit, without having to
* avoid any code or data used by any SW CPU pin loop. The CPU hotplug
- * functionality embodied in disable_nonboot_cpus() to achieve this.
+ * functionality embodied in smpt_shutdown_nonboot_cpus() to achieve this.
*/
void machine_shutdown(void)
{
- disable_nonboot_cpus();
+ smp_shutdown_nonboot_cpus(reboot_cpu);
}
/*
--
2.17.1
On Sun, Feb 23, 2020 at 07:29:32PM +0000, Qais Yousef wrote:
> disable_nonboot_cpus() is not safe to use when doing machine_down(),
> because it relies on freeze_secondary_cpus() which in turn is
> a suspend/resume related freeze and could abort if the logic detects any
> pending activities that can prevent finishing the offlining process.
>
> Beside disable_nonboot_cpus() is dependent on CONFIG_PM_SLEEP_SMP which
> is an othogonal config to rely on to ensure this function works
> correctly.
>
> Use `reboot_cpu` variable instead of hardcoding 0 as the reboot cpu.
>
> Signed-off-by: Qais Yousef <[email protected]>
> CC: Catalin Marinas <[email protected]>
> CC: Will Deacon <[email protected]>
> CC: [email protected]
> CC: [email protected]
I'm not sure whether these patches have been queued already (still
unread in my inbox), so here it is:
Acked-by: Catalin Marinas <[email protected]>
On 03/17/20 11:21, Catalin Marinas wrote:
> On Sun, Feb 23, 2020 at 07:29:32PM +0000, Qais Yousef wrote:
> > disable_nonboot_cpus() is not safe to use when doing machine_down(),
> > because it relies on freeze_secondary_cpus() which in turn is
> > a suspend/resume related freeze and could abort if the logic detects any
> > pending activities that can prevent finishing the offlining process.
> >
> > Beside disable_nonboot_cpus() is dependent on CONFIG_PM_SLEEP_SMP which
> > is an othogonal config to rely on to ensure this function works
> > correctly.
> >
> > Use `reboot_cpu` variable instead of hardcoding 0 as the reboot cpu.
> >
> > Signed-off-by: Qais Yousef <[email protected]>
> > CC: Catalin Marinas <[email protected]>
> > CC: Will Deacon <[email protected]>
> > CC: [email protected]
> > CC: [email protected]
>
> I'm not sure whether these patches have been queued already (still
> unread in my inbox), so here it is:
>
> Acked-by: Catalin Marinas <[email protected]>
Thanks Catalin!
Russel has requested to split the arm patch into 2 so that the change to
use reboot_cpu is in a separate patch. I'll do the same for arm64 to stay
consistent. I'll add your Acked-by to both patches if that's okay.
Please shout if you have any objection.
Thanks
--
Qais Yousef