From 737ffb27f2f1a8fe6644cac535486f7f25bbf6cb Mon Sep 17 00:00:00 2001 From: Viresh Kumar Date: Tue, 22 Oct 2019 15:47:57 +0530 Subject: [PATCH 1/4] cpufreq: Clarify the comment in cpufreq_set_policy() One of the responsibility of the ->verify() callback is to make sure that the policy's min frequency is <= max frequency as this isn't guaranteed by the QoS framework which gave us those values. Update the comment in cpufreq_set_policy() to clarify that. Suggested-by: Rafael J. Wysocki Signed-off-by: Viresh Kumar [ rjw: Minor changes of the new comment ] Signed-off-by: Rafael J. Wysocki --- drivers/cpufreq/cpufreq.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index 48a224a6b1781..dd16281923100 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -2385,7 +2385,10 @@ int cpufreq_set_policy(struct cpufreq_policy *policy, new_policy->min = freq_qos_read_value(&policy->constraints, FREQ_QOS_MIN); new_policy->max = freq_qos_read_value(&policy->constraints, FREQ_QOS_MAX); - /* verify the cpu speed can be set within this limit */ + /* + * Verify that the CPU speed can be set within these limits and make sure + * that min <= max. + */ ret = cpufreq_driver->verify(new_policy); if (ret) return ret; From db0d32d84031188443e25edbd50a71a6e7ac5d1d Mon Sep 17 00:00:00 2001 From: John Hubbard Date: Wed, 30 Oct 2019 22:21:59 -0700 Subject: [PATCH 2/4] cpufreq: powernv: fix stack bloat and hard limit on number of CPUs The following build warning occurred on powerpc 64-bit builds: drivers/cpufreq/powernv-cpufreq.c: In function 'init_chip_info': drivers/cpufreq/powernv-cpufreq.c:1070:1: warning: the frame size of 1040 bytes is larger than 1024 bytes [-Wframe-larger-than=] This is with a cross-compiler based on gcc 8.1.0, which I got from: https://mirrors.edge.kernel.org/pub/tools/crosstool/files/bin/x86_64/8.1.0/ The warning is due to putting 1024 bytes on the stack: unsigned int chip[256]; ...and it's also undesirable to have a hard limit on the number of CPUs here. Fix both problems by dynamically allocating based on num_possible_cpus, as recommended by Michael Ellerman. Fixes: 053819e0bf840 ("cpufreq: powernv: Handle throttling due to Pmax capping at chip level") Signed-off-by: John Hubbard Acked-by: Viresh Kumar Cc: 4.10+ # 4.10+ Signed-off-by: Rafael J. Wysocki --- drivers/cpufreq/powernv-cpufreq.c | 17 +++++++++++++---- 1 file changed, 13 insertions(+), 4 deletions(-) diff --git a/drivers/cpufreq/powernv-cpufreq.c b/drivers/cpufreq/powernv-cpufreq.c index 6061850e59c90..56f4bc0d209ec 100644 --- a/drivers/cpufreq/powernv-cpufreq.c +++ b/drivers/cpufreq/powernv-cpufreq.c @@ -1041,9 +1041,14 @@ static struct cpufreq_driver powernv_cpufreq_driver = { static int init_chip_info(void) { - unsigned int chip[256]; + unsigned int *chip; unsigned int cpu, i; unsigned int prev_chip_id = UINT_MAX; + int ret = 0; + + chip = kcalloc(num_possible_cpus(), sizeof(*chip), GFP_KERNEL); + if (!chip) + return -ENOMEM; for_each_possible_cpu(cpu) { unsigned int id = cpu_to_chip_id(cpu); @@ -1055,8 +1060,10 @@ static int init_chip_info(void) } chips = kcalloc(nr_chips, sizeof(struct chip), GFP_KERNEL); - if (!chips) - return -ENOMEM; + if (!chips) { + ret = -ENOMEM; + goto free_and_return; + } for (i = 0; i < nr_chips; i++) { chips[i].id = chip[i]; @@ -1066,7 +1073,9 @@ static int init_chip_info(void) per_cpu(chip_info, cpu) = &chips[i]; } - return 0; +free_and_return: + kfree(chip); + return ret; } static inline void clean_chip_info(void) From 8d2eecead5bf23865cb73062a4e7139a9dbce5a1 Mon Sep 17 00:00:00 2001 From: Jamal Shareef Date: Mon, 4 Nov 2019 21:54:27 -0800 Subject: [PATCH 3/4] cpufreq: intel_pstate: Fix plain int as pointer warning from sparse Fix sparse warning: Using plain integer as NULL pointer. Replace assignment of 0 to pointers with NULL assignment. Signed-off-by: Jamal Shareef Signed-off-by: Rafael J. Wysocki --- drivers/cpufreq/intel_pstate.c | 30 +++++++++++++++--------------- 1 file changed, 15 insertions(+), 15 deletions(-) diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c index 53a51c169451f..cfcf34e04c3d0 100644 --- a/drivers/cpufreq/intel_pstate.c +++ b/drivers/cpufreq/intel_pstate.c @@ -2664,21 +2664,21 @@ enum { /* Hardware vendor-specific info that has its own power management modes */ static struct acpi_platform_list plat_info[] __initdata = { - {"HP ", "ProLiant", 0, ACPI_SIG_FADT, all_versions, 0, PSS}, - {"ORACLE", "X4-2 ", 0, ACPI_SIG_FADT, all_versions, 0, PPC}, - {"ORACLE", "X4-2L ", 0, ACPI_SIG_FADT, all_versions, 0, PPC}, - {"ORACLE", "X4-2B ", 0, ACPI_SIG_FADT, all_versions, 0, PPC}, - {"ORACLE", "X3-2 ", 0, ACPI_SIG_FADT, all_versions, 0, PPC}, - {"ORACLE", "X3-2L ", 0, ACPI_SIG_FADT, all_versions, 0, PPC}, - {"ORACLE", "X3-2B ", 0, ACPI_SIG_FADT, all_versions, 0, PPC}, - {"ORACLE", "X4470M2 ", 0, ACPI_SIG_FADT, all_versions, 0, PPC}, - {"ORACLE", "X4270M3 ", 0, ACPI_SIG_FADT, all_versions, 0, PPC}, - {"ORACLE", "X4270M2 ", 0, ACPI_SIG_FADT, all_versions, 0, PPC}, - {"ORACLE", "X4170M2 ", 0, ACPI_SIG_FADT, all_versions, 0, PPC}, - {"ORACLE", "X4170 M3", 0, ACPI_SIG_FADT, all_versions, 0, PPC}, - {"ORACLE", "X4275 M3", 0, ACPI_SIG_FADT, all_versions, 0, PPC}, - {"ORACLE", "X6-2 ", 0, ACPI_SIG_FADT, all_versions, 0, PPC}, - {"ORACLE", "Sudbury ", 0, ACPI_SIG_FADT, all_versions, 0, PPC}, + {"HP ", "ProLiant", 0, ACPI_SIG_FADT, all_versions, NULL, PSS}, + {"ORACLE", "X4-2 ", 0, ACPI_SIG_FADT, all_versions, NULL, PPC}, + {"ORACLE", "X4-2L ", 0, ACPI_SIG_FADT, all_versions, NULL, PPC}, + {"ORACLE", "X4-2B ", 0, ACPI_SIG_FADT, all_versions, NULL, PPC}, + {"ORACLE", "X3-2 ", 0, ACPI_SIG_FADT, all_versions, NULL, PPC}, + {"ORACLE", "X3-2L ", 0, ACPI_SIG_FADT, all_versions, NULL, PPC}, + {"ORACLE", "X3-2B ", 0, ACPI_SIG_FADT, all_versions, NULL, PPC}, + {"ORACLE", "X4470M2 ", 0, ACPI_SIG_FADT, all_versions, NULL, PPC}, + {"ORACLE", "X4270M3 ", 0, ACPI_SIG_FADT, all_versions, NULL, PPC}, + {"ORACLE", "X4270M2 ", 0, ACPI_SIG_FADT, all_versions, NULL, PPC}, + {"ORACLE", "X4170M2 ", 0, ACPI_SIG_FADT, all_versions, NULL, PPC}, + {"ORACLE", "X4170 M3", 0, ACPI_SIG_FADT, all_versions, NULL, PPC}, + {"ORACLE", "X4275 M3", 0, ACPI_SIG_FADT, all_versions, NULL, PPC}, + {"ORACLE", "X6-2 ", 0, ACPI_SIG_FADT, all_versions, NULL, PPC}, + {"ORACLE", "Sudbury ", 0, ACPI_SIG_FADT, all_versions, NULL, PPC}, { } /* End */ }; From e6e8df07268c1f75dd9215536e2ce4587b70f977 Mon Sep 17 00:00:00 2001 From: Kai Shen Date: Thu, 7 Nov 2019 05:08:17 +0000 Subject: [PATCH 4/4] cpufreq: Add NULL checks to show() and store() methods of cpufreq Add NULL checks to show() and store() in cpufreq.c to avoid attempts to invoke a NULL callback. Though some interfaces of cpufreq are set as read-only, users can still get write permission using chmod which can lead to a kernel crash, as follows: chmod +w /sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq echo 1 > /sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq This bug was found in linux 4.19. Signed-off-by: Kai Shen Reported-by: Feilong Lin Reviewed-by: Feilong Lin Acked-by: Viresh Kumar [ rjw: Subject & changelog ] Cc: All applicable Signed-off-by: Rafael J. Wysocki --- drivers/cpufreq/cpufreq.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index dd16281923100..0a10cf9d0b1ad 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -933,6 +933,9 @@ static ssize_t show(struct kobject *kobj, struct attribute *attr, char *buf) struct freq_attr *fattr = to_attr(attr); ssize_t ret; + if (!fattr->show) + return -EIO; + down_read(&policy->rwsem); ret = fattr->show(policy, buf); up_read(&policy->rwsem); @@ -947,6 +950,9 @@ static ssize_t store(struct kobject *kobj, struct attribute *attr, struct freq_attr *fattr = to_attr(attr); ssize_t ret = -EINVAL; + if (!fattr->store) + return -EIO; + /* * cpus_read_trylock() is used here to work around a circular lock * dependency problem with respect to the cpufreq_register_driver().