From: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com> variable flat_state_cnt mainline inclusion from mainline-v6.18-rc1 commit e4c628e91c6ab12f89500a023adfb030f737f3fd category: bugfix bugzilla: https://atomgit.com/openeuler/kernel/issues/9134 CVE: NA Reference: https://web.git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commi... ---------------------------------------------------------------------- Instead of using static variable flat_state_cnt to pass data between functions involved in the _LPI information processing, pass the current number of "flattened" idle states to flatten_lpi_states() and make it return the updated number of those states. At the same time, use a local variable called state_count to store the number of "flattened" idle states found so far in acpi_processor_get_lpi_info(). No intentional functional impact. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Sudeep Holla <sudeep.holla@arm.com> Tested-by: Sudeep Holla <sudeep.holla@arm.com> Acked-by: lihuisong@huawei.com Link: https://patch.msgid.link/10715991.nUPlyArG6x@rafael.j.wysocki Signed-off-by: Huisong Li <lihuisong@huawei.com> Signed-off-by: Hongye Lin <linhongye@h-partners.com> --- drivers/acpi/processor_idle.c | 25 +++++++++++-------------- 1 file changed, 11 insertions(+), 14 deletions(-) diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c index ad3de5200c0b..986b6fddbcd9 100644 --- a/drivers/acpi/processor_idle.c +++ b/drivers/acpi/processor_idle.c @@ -1009,11 +1009,6 @@ static int acpi_processor_evaluate_lpi(acpi_handle handle, return ret; } -/* - * flat_state_cnt - the number of composite LPI states after the process of flattening - */ -static int flat_state_cnt; - /** * combine_lpi_states - combine local and parent LPI states to form a composite LPI state * @@ -1056,9 +1051,10 @@ static void stash_composite_state(struct acpi_lpi_states_array *curr_level, curr_level->composite_states[curr_level->composite_states_size++] = t; } -static int flatten_lpi_states(struct acpi_processor *pr, - struct acpi_lpi_states_array *curr_level, - struct acpi_lpi_states_array *prev_level) +static unsigned int flatten_lpi_states(struct acpi_processor *pr, + unsigned int flat_state_cnt, + struct acpi_lpi_states_array *curr_level, + struct acpi_lpi_states_array *prev_level) { int i, j, state_count = curr_level->size; struct acpi_lpi_state *p, *t = curr_level->entries; @@ -1098,7 +1094,7 @@ static int flatten_lpi_states(struct acpi_processor *pr, } kfree(curr_level->entries); - return 0; + return flat_state_cnt; } int __weak acpi_processor_ffh_lpi_probe(unsigned int cpu) @@ -1113,6 +1109,7 @@ static int acpi_processor_get_lpi_info(struct acpi_processor *pr) acpi_handle handle = pr->handle, pr_ahandle; struct acpi_device *d = NULL; struct acpi_lpi_states_array info[2], *tmp, *prev, *curr; + unsigned int state_count; /* make sure our architecture has support */ ret = acpi_processor_ffh_lpi_probe(pr->id); @@ -1125,14 +1122,13 @@ static int acpi_processor_get_lpi_info(struct acpi_processor *pr) if (!acpi_has_method(handle, "_LPI")) return -EINVAL; - flat_state_cnt = 0; prev = &info[0]; curr = &info[1]; handle = pr->handle; ret = acpi_processor_evaluate_lpi(handle, prev); if (ret) return ret; - flatten_lpi_states(pr, prev, NULL); + state_count = flatten_lpi_states(pr, 0, prev, NULL); status = acpi_get_parent(handle, &pr_ahandle); while (ACPI_SUCCESS(status)) { @@ -1154,18 +1150,19 @@ static int acpi_processor_get_lpi_info(struct acpi_processor *pr) break; /* flatten all the LPI states in this level of hierarchy */ - flatten_lpi_states(pr, curr, prev); + state_count = flatten_lpi_states(pr, state_count, curr, prev); tmp = prev, prev = curr, curr = tmp; status = acpi_get_parent(handle, &pr_ahandle); } - pr->power.count = flat_state_cnt; /* reset the index after flattening */ - for (i = 0; i < pr->power.count; i++) + for (i = 0; i < state_count; i++) pr->power.lpi_states[i].index = i; + pr->power.count = state_count; + /* Tell driver that _LPI is supported. */ pr->flags.has_lpi = 1; pr->flags.power = 1; -- 2.33.0