kernel/reboot.c | 43 +++++++++++++++++++++++++++++++++++++------ 1 file changed, 37 insertions(+), 6 deletions(-)
The register_platform_power_off() fails on m68k platform due to the
memory allocation error that happens at a very early boot time when
memory allocator isn't available yet. Fix it by using a static sys-off
handler for the platform-level power-off handlers.
Fixes: f0f7e5265b3b ("m68k: Switch to new sys-off handler API")
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
---
kernel/reboot.c | 43 +++++++++++++++++++++++++++++++++++++------
1 file changed, 37 insertions(+), 6 deletions(-)
diff --git a/kernel/reboot.c b/kernel/reboot.c
index a091145ee710..3b19b123efec 100644
--- a/kernel/reboot.c
+++ b/kernel/reboot.c
@@ -315,6 +315,37 @@ static int sys_off_notify(struct notifier_block *nb,
return handler->sys_off_cb(&data);
}
+static struct sys_off_handler platform_sys_off_handler;
+
+static struct sys_off_handler *alloc_sys_off_handler(int priority)
+{
+ struct sys_off_handler *handler;
+
+ /*
+ * Platforms like m68k can't allocate sys_off handler dynamically
+ * at the early boot time because memory allocator isn't available yet.
+ */
+ if (priority == SYS_OFF_PRIO_PLATFORM) {
+ handler = &platform_sys_off_handler;
+ if (handler->cb_data)
+ return ERR_PTR(-EBUSY);
+ } else {
+ handler = kzalloc(sizeof(*handler), GFP_KERNEL);
+ if (!handler)
+ return ERR_PTR(-ENOMEM);
+ }
+
+ return handler;
+}
+
+static void free_sys_off_handler(struct sys_off_handler *handler)
+{
+ if (handler == &platform_sys_off_handler)
+ memset(handler, 0, sizeof(*handler));
+ else
+ kfree(handler);
+}
+
/**
* register_sys_off_handler - Register sys-off handler
* @mode: Sys-off mode
@@ -345,9 +376,9 @@ register_sys_off_handler(enum sys_off_mode mode,
struct sys_off_handler *handler;
int err;
- handler = kzalloc(sizeof(*handler), GFP_KERNEL);
- if (!handler)
- return ERR_PTR(-ENOMEM);
+ handler = alloc_sys_off_handler(priority);
+ if (IS_ERR(handler))
+ return handler;
switch (mode) {
case SYS_OFF_MODE_POWER_OFF_PREPARE:
@@ -364,7 +395,7 @@ register_sys_off_handler(enum sys_off_mode mode,
break;
default:
- kfree(handler);
+ free_sys_off_handler(handler);
return ERR_PTR(-EINVAL);
}
@@ -391,7 +422,7 @@ register_sys_off_handler(enum sys_off_mode mode,
}
if (err) {
- kfree(handler);
+ free_sys_off_handler(handler);
return ERR_PTR(err);
}
@@ -422,7 +453,7 @@ void unregister_sys_off_handler(struct sys_off_handler *handler)
/* sanity check, shall never happen */
WARN_ON(err);
- kfree(handler);
+ free_sys_off_handler(handler);
}
EXPORT_SYMBOL_GPL(unregister_sys_off_handler);
--
2.35.3On Wed, Jun 1, 2022 at 12:11 AM Dmitry Osipenko
<dmitry.osipenko@collabora.com> wrote:
>
> The register_platform_power_off() fails on m68k platform due to the
> memory allocation error that happens at a very early boot time when
> memory allocator isn't available yet. Fix it by using a static sys-off
> handler for the platform-level power-off handlers.
>
> Fixes: f0f7e5265b3b ("m68k: Switch to new sys-off handler API")
> Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
> Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
> ---
> kernel/reboot.c | 43 +++++++++++++++++++++++++++++++++++++------
> 1 file changed, 37 insertions(+), 6 deletions(-)
>
> diff --git a/kernel/reboot.c b/kernel/reboot.c
> index a091145ee710..3b19b123efec 100644
> --- a/kernel/reboot.c
> +++ b/kernel/reboot.c
> @@ -315,6 +315,37 @@ static int sys_off_notify(struct notifier_block *nb,
> return handler->sys_off_cb(&data);
> }
>
> +static struct sys_off_handler platform_sys_off_handler;
> +
> +static struct sys_off_handler *alloc_sys_off_handler(int priority)
> +{
> + struct sys_off_handler *handler;
> +
> + /*
> + * Platforms like m68k can't allocate sys_off handler dynamically
> + * at the early boot time because memory allocator isn't available yet.
> + */
> + if (priority == SYS_OFF_PRIO_PLATFORM) {
> + handler = &platform_sys_off_handler;
> + if (handler->cb_data)
> + return ERR_PTR(-EBUSY);
> + } else {
> + handler = kzalloc(sizeof(*handler), GFP_KERNEL);
> + if (!handler)
> + return ERR_PTR(-ENOMEM);
> + }
> +
> + return handler;
> +}
> +
> +static void free_sys_off_handler(struct sys_off_handler *handler)
> +{
> + if (handler == &platform_sys_off_handler)
> + memset(handler, 0, sizeof(*handler));
> + else
> + kfree(handler);
> +}
> +
> /**
> * register_sys_off_handler - Register sys-off handler
> * @mode: Sys-off mode
> @@ -345,9 +376,9 @@ register_sys_off_handler(enum sys_off_mode mode,
> struct sys_off_handler *handler;
> int err;
>
> - handler = kzalloc(sizeof(*handler), GFP_KERNEL);
> - if (!handler)
> - return ERR_PTR(-ENOMEM);
> + handler = alloc_sys_off_handler(priority);
> + if (IS_ERR(handler))
> + return handler;
>
> switch (mode) {
> case SYS_OFF_MODE_POWER_OFF_PREPARE:
> @@ -364,7 +395,7 @@ register_sys_off_handler(enum sys_off_mode mode,
> break;
>
> default:
> - kfree(handler);
> + free_sys_off_handler(handler);
> return ERR_PTR(-EINVAL);
> }
>
> @@ -391,7 +422,7 @@ register_sys_off_handler(enum sys_off_mode mode,
> }
>
> if (err) {
> - kfree(handler);
> + free_sys_off_handler(handler);
> return ERR_PTR(err);
> }
>
> @@ -422,7 +453,7 @@ void unregister_sys_off_handler(struct sys_off_handler *handler)
> /* sanity check, shall never happen */
> WARN_ON(err);
>
> - kfree(handler);
> + free_sys_off_handler(handler);
> }
> EXPORT_SYMBOL_GPL(unregister_sys_off_handler);
>
> --
Applied now (with the tags from Geert), but if there are any more
followup changes in that area, can you please CC them to linux-pm, so
people who have seen your original series can see them too?
Thanks!
On 6/2/22 21:40, Rafael J. Wysocki wrote: .. > Applied now (with the tags from Geert), but if there are any more > followup changes in that area, can you please CC them to linux-pm, so > people who have seen your original series can see them too? > > Thanks! Sure, I actually wanted to CC linux-pm, but missed twice to update the send-mail command from the bash history. Thank you all! -- Best regards, Dmitry
Hi Dmitry,
On Wed, Jun 1, 2022 at 12:11 AM Dmitry Osipenko
<dmitry.osipenko@collabora.com> wrote:
> The register_platform_power_off() fails on m68k platform due to the
> memory allocation error that happens at a very early boot time when
> memory allocator isn't available yet. Fix it by using a static sys-off
> handler for the platform-level power-off handlers.
>
> Fixes: f0f7e5265b3b ("m68k: Switch to new sys-off handler API")
> Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
> Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
Thank you, that fixes the issue.
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
© 2016 - 2026 Red Hat, Inc.