| Message ID | 20220606165640.634811-1-dmitry.osipenko@collabora.com (mailing list archive) |
|---|---|
| State | Mainlined, archived |
| Headers | show |
| Series | [v1] kernel/reboot: Fix powering off using a non-syscall code paths | expand |
On Mon, Jun 6, 2022 at 6:57 PM Dmitry Osipenko <dmitry.osipenko@collabora.com> wrote: > > There are other methods of powering off machine than the reboot syscall. > Previously we missed to coved those methods and it created power-off > regression for some machines, like the PowerPC e500. Fix this problem > by moving the legacy sys-off handler registration to the latest phase > of power-off process and making the kernel_can_power_off() to check the > legacy pm_power_off presence. > > Tested-by: Michael Ellerman <mpe@ellerman.id.au> # ppce500 > Reported-by: Michael Ellerman <mpe@ellerman.id.au> # ppce500 > Fixes: da007f171fc9 ("kernel/reboot: Change registration order of legacy power-off handler") > Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com> > --- > kernel/reboot.c | 46 ++++++++++++++++++++++++++-------------------- > 1 file changed, 26 insertions(+), 20 deletions(-) > > diff --git a/kernel/reboot.c b/kernel/reboot.c > index 3b19b123efec..b5a71d1ff603 100644 > --- a/kernel/reboot.c > +++ b/kernel/reboot.c > @@ -320,6 +320,7 @@ 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; > + gfp_t flags; > > /* > * Platforms like m68k can't allocate sys_off handler dynamically > @@ -330,7 +331,12 @@ static struct sys_off_handler *alloc_sys_off_handler(int priority) > if (handler->cb_data) > return ERR_PTR(-EBUSY); > } else { > - handler = kzalloc(sizeof(*handler), GFP_KERNEL); > + if (system_state > SYSTEM_RUNNING) > + flags = GFP_ATOMIC; > + else > + flags = GFP_KERNEL; > + > + handler = kzalloc(sizeof(*handler), flags); > if (!handler) > return ERR_PTR(-ENOMEM); > } > @@ -440,7 +446,7 @@ void unregister_sys_off_handler(struct sys_off_handler *handler) > { > int err; > > - if (!handler) > + if (IS_ERR_OR_NULL(handler)) > return; > > if (handler->blocking) > @@ -615,7 +621,23 @@ static void do_kernel_power_off_prepare(void) > */ > void do_kernel_power_off(void) > { > + struct sys_off_handler *sys_off = NULL; > + > + /* > + * Register sys-off handlers for legacy PM callback. This allows > + * legacy PM callbacks temporary co-exist with the new sys-off API. > + * > + * TODO: Remove legacy handlers once all legacy PM users will be > + * switched to the sys-off based APIs. > + */ > + if (pm_power_off) > + sys_off = register_sys_off_handler(SYS_OFF_MODE_POWER_OFF, > + SYS_OFF_PRIO_DEFAULT, > + legacy_pm_power_off, NULL); > + > atomic_notifier_call_chain(&power_off_handler_list, 0, NULL); > + > + unregister_sys_off_handler(sys_off); > } > > /** > @@ -626,7 +648,8 @@ void do_kernel_power_off(void) > */ > bool kernel_can_power_off(void) > { > - return !atomic_notifier_call_chain_is_empty(&power_off_handler_list); > + return !atomic_notifier_call_chain_is_empty(&power_off_handler_list) || > + pm_power_off; > } > EXPORT_SYMBOL_GPL(kernel_can_power_off); > > @@ -661,7 +684,6 @@ SYSCALL_DEFINE4(reboot, int, magic1, int, magic2, unsigned int, cmd, > void __user *, arg) > { > struct pid_namespace *pid_ns = task_active_pid_ns(current); > - struct sys_off_handler *sys_off = NULL; > char buffer[256]; > int ret = 0; > > @@ -686,21 +708,6 @@ SYSCALL_DEFINE4(reboot, int, magic1, int, magic2, unsigned int, cmd, > if (ret) > return ret; > > - /* > - * Register sys-off handlers for legacy PM callback. This allows > - * legacy PM callbacks temporary co-exist with the new sys-off API. > - * > - * TODO: Remove legacy handlers once all legacy PM users will be > - * switched to the sys-off based APIs. > - */ > - if (pm_power_off) { > - sys_off = register_sys_off_handler(SYS_OFF_MODE_POWER_OFF, > - SYS_OFF_PRIO_DEFAULT, > - legacy_pm_power_off, NULL); > - if (IS_ERR(sys_off)) > - return PTR_ERR(sys_off); > - } > - > /* Instead of trying to make the power_off code look like > * halt when pm_power_off is not set do it the easy way. > */ > @@ -758,7 +765,6 @@ SYSCALL_DEFINE4(reboot, int, magic1, int, magic2, unsigned int, cmd, > break; > } > mutex_unlock(&system_transition_mutex); > - unregister_sys_off_handler(sys_off); > return ret; > } > > -- Applied (with a couple of edits in the changelog), thanks!
diff --git a/kernel/reboot.c b/kernel/reboot.c index 3b19b123efec..b5a71d1ff603 100644 --- a/kernel/reboot.c +++ b/kernel/reboot.c @@ -320,6 +320,7 @@ 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; + gfp_t flags; /* * Platforms like m68k can't allocate sys_off handler dynamically @@ -330,7 +331,12 @@ static struct sys_off_handler *alloc_sys_off_handler(int priority) if (handler->cb_data) return ERR_PTR(-EBUSY); } else { - handler = kzalloc(sizeof(*handler), GFP_KERNEL); + if (system_state > SYSTEM_RUNNING) + flags = GFP_ATOMIC; + else + flags = GFP_KERNEL; + + handler = kzalloc(sizeof(*handler), flags); if (!handler) return ERR_PTR(-ENOMEM); } @@ -440,7 +446,7 @@ void unregister_sys_off_handler(struct sys_off_handler *handler) { int err; - if (!handler) + if (IS_ERR_OR_NULL(handler)) return; if (handler->blocking) @@ -615,7 +621,23 @@ static void do_kernel_power_off_prepare(void) */ void do_kernel_power_off(void) { + struct sys_off_handler *sys_off = NULL; + + /* + * Register sys-off handlers for legacy PM callback. This allows + * legacy PM callbacks temporary co-exist with the new sys-off API. + * + * TODO: Remove legacy handlers once all legacy PM users will be + * switched to the sys-off based APIs. + */ + if (pm_power_off) + sys_off = register_sys_off_handler(SYS_OFF_MODE_POWER_OFF, + SYS_OFF_PRIO_DEFAULT, + legacy_pm_power_off, NULL); + atomic_notifier_call_chain(&power_off_handler_list, 0, NULL); + + unregister_sys_off_handler(sys_off); } /** @@ -626,7 +648,8 @@ void do_kernel_power_off(void) */ bool kernel_can_power_off(void) { - return !atomic_notifier_call_chain_is_empty(&power_off_handler_list); + return !atomic_notifier_call_chain_is_empty(&power_off_handler_list) || + pm_power_off; } EXPORT_SYMBOL_GPL(kernel_can_power_off); @@ -661,7 +684,6 @@ SYSCALL_DEFINE4(reboot, int, magic1, int, magic2, unsigned int, cmd, void __user *, arg) { struct pid_namespace *pid_ns = task_active_pid_ns(current); - struct sys_off_handler *sys_off = NULL; char buffer[256]; int ret = 0; @@ -686,21 +708,6 @@ SYSCALL_DEFINE4(reboot, int, magic1, int, magic2, unsigned int, cmd, if (ret) return ret; - /* - * Register sys-off handlers for legacy PM callback. This allows - * legacy PM callbacks temporary co-exist with the new sys-off API. - * - * TODO: Remove legacy handlers once all legacy PM users will be - * switched to the sys-off based APIs. - */ - if (pm_power_off) { - sys_off = register_sys_off_handler(SYS_OFF_MODE_POWER_OFF, - SYS_OFF_PRIO_DEFAULT, - legacy_pm_power_off, NULL); - if (IS_ERR(sys_off)) - return PTR_ERR(sys_off); - } - /* Instead of trying to make the power_off code look like * halt when pm_power_off is not set do it the easy way. */ @@ -758,7 +765,6 @@ SYSCALL_DEFINE4(reboot, int, magic1, int, magic2, unsigned int, cmd, break; } mutex_unlock(&system_transition_mutex); - unregister_sys_off_handler(sys_off); return ret; }