The following commit has been merged into the smp/urgent branch of tip: Commit-ID: 932d8476399f622aa0767a4a0a9e78e5341dc0e1 Gitweb: https://git.kernel.org/tip/932d8476399f622aa0767a4a0a9e78e5341dc0e1 Author: Yuntao Wang <ytcoode@xxxxxxxxx> AuthorDate: Wed, 15 May 2024 21:45:54 +08:00 Committer: Thomas Gleixner <tglx@xxxxxxxxxxxxx> CommitterDate: Mon, 17 Jun 2024 15:08:04 +02:00 cpu/hotplug: Fix dynstate assignment in __cpuhp_setup_state_cpuslocked() Commit 4205e4786d0b ("cpu/hotplug: Provide dynamic range for prepare stage") added a dynamic range for the prepare states, but did not handle the assignment of the dynstate variable in __cpuhp_setup_state_cpuslocked(). This causes the corresponding startup callback not to be invoked when calling __cpuhp_setup_state_cpuslocked() with the CPUHP_BP_PREPARE_DYN parameter, even though it should be. Currently, the users of __cpuhp_setup_state_cpuslocked(), for one reason or another, have not triggered this bug. Fixes: 4205e4786d0b ("cpu/hotplug: Provide dynamic range for prepare stage") Signed-off-by: Yuntao Wang <ytcoode@xxxxxxxxx> Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx Link: https://lore.kernel.org/r/20240515134554.427071-1-ytcoode@xxxxxxxxx --- kernel/cpu.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/kernel/cpu.c b/kernel/cpu.c index 563877d..74cfdb6 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -2446,7 +2446,7 @@ EXPORT_SYMBOL_GPL(__cpuhp_state_add_instance); * The caller needs to hold cpus read locked while calling this function. * Return: * On success: - * Positive state number if @state is CPUHP_AP_ONLINE_DYN; + * Positive state number if @state is CPUHP_AP_ONLINE_DYN or CPUHP_BP_PREPARE_DYN; * 0 for all other states * On failure: proper (negative) error code */ @@ -2469,7 +2469,7 @@ int __cpuhp_setup_state_cpuslocked(enum cpuhp_state state, ret = cpuhp_store_callbacks(state, name, startup, teardown, multi_instance); - dynstate = state == CPUHP_AP_ONLINE_DYN; + dynstate = state == CPUHP_AP_ONLINE_DYN || state == CPUHP_BP_PREPARE_DYN; if (ret > 0 && dynstate) { state = ret; ret = 0; @@ -2500,8 +2500,8 @@ int __cpuhp_setup_state_cpuslocked(enum cpuhp_state state, out: mutex_unlock(&cpuhp_state_mutex); /* - * If the requested state is CPUHP_AP_ONLINE_DYN, return the - * dynamically allocated state in case of success. + * If the requested state is CPUHP_AP_ONLINE_DYN or CPUHP_BP_PREPARE_DYN, + * return the dynamically allocated state in case of success. */ if (!ret && dynstate) return state;
