diff options
author | John Hubbard <jhubbard@nvidia.com> | 2019-10-31 08:21:59 +0300 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-12-17 21:56:26 +0300 |
commit | 5ec6a40b88d8d791adcaa5503ed7c8d6ab5013b2 (patch) | |
tree | 3bca8bffa23dc7ddc8417be3aced9d1f89cb83a4 /drivers/cpufreq | |
parent | 1b5d4a3a0957dbbd403a3f1ce3a6e23b5d3db2c0 (diff) | |
download | linux-5ec6a40b88d8d791adcaa5503ed7c8d6ab5013b2.tar.xz |
cpufreq: powernv: fix stack bloat and hard limit on number of CPUs
commit db0d32d84031188443e25edbd50a71a6e7ac5d1d upstream.
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 <jhubbard@nvidia.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: 4.10+ <stable@vger.kernel.org> # 4.10+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/cpufreq')
-rw-r--r-- | drivers/cpufreq/powernv-cpufreq.c | 17 |
1 files changed, 13 insertions, 4 deletions
diff --git a/drivers/cpufreq/powernv-cpufreq.c b/drivers/cpufreq/powernv-cpufreq.c index 6061850e59c9..56f4bc0d209e 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) |