xavi/android_kernel_m2note/drivers/cpufreq, branch ng-7.1.2

cpufreq: Fix timer/workqueue corruption by protecting reading governor_enabled

2019-05-03T14:07:03+00:00

When a CPU is hot removed we'll cancel all the delayed work items via gov_cancel_work(). Sometimes the delayed work function determines that it should adjust the delay for all other CPUs that the policy is managing. If this scenario occurs, the canceling CPU will cancel its own work but queue up the other CPUs works to run. Commit 3617f2 (cpufreq: Fix timer/workqueue corruption due to double queueing) has tried to fix this, but reading governor_enabled is not protected by cpufreq_governor_lock. Even though od_dbs_timer() checks governor_enabled before gov_queue_work(), this scenario may occur. For example: CPU0 CPU1 ---- ---- cpu_down() ... __cpufreq_remove_dev() od_dbs_timer() __cpufreq_governor() policy->governor_enabled policy->governor_enabled = false; cpufreq_governor_dbs() case CPUFREQ_GOV_STOP: gov_cancel_work(dbs_data, policy); cpu0 work is canceled timer is canceled cpu1 work is canceled gov_queue_work(*, *, true); cpu0 work queued cpu1 work queued cpu2 work queued ... cpu1 work is canceled cpu2 work is canceled ... At the end of the GOV_STOP case cpu0 still has a work queued to run although the code is expecting all of the works to be canceled. __cpufreq_remove_dev() will then proceed to re-initialize all the other CPUs works except for the CPU that is going down. The CPUFREQ_GOV_START case in cpufreq_governor_dbs() will trample over the queued work and debugobjects will spit out a warning: WARNING: at lib/debugobjects.c:260 debug_print_object+0x94/0xbc() ODEBUG: init active (active state 0) object type: timer_list hint: delayed_work_timer_fn+0x0/0x14 Modules linked in: CPU: 1 PID: 1205 Comm: sh Tainted: G W 3.10.0 #200 [] (unwind_backtrace+0x0/0xf8) from [] (show_stack+0x10/0x14) [] (show_stack+0x10/0x14) from [] (warn_slowpath_common+0x4c/0x68) [] (warn_slowpath_common+0x4c/0x68) from [] (warn_slowpath_fmt+0x30/0x40) [] (warn_slowpath_fmt+0x30/0x40) from [] (debug_print_object+0x94/0xbc) [] (debug_print_object+0x94/0xbc) from [] (__debug_object_init+0xc8/0x3c0) [] (__debug_object_init+0xc8/0x3c0) from [] (init_timer_key+0x20/0x104) [] (init_timer_key+0x20/0x104) from [] (cpufreq_governor_dbs+0x1dc/0x68c) [] (cpufreq_governor_dbs+0x1dc/0x68c) from [] (__cpufreq_governor+0x80/0x1b0) [] (__cpufreq_governor+0x80/0x1b0) from [] (__cpufreq_remove_dev.isra.12+0x22c/0x380) [] (__cpufreq_remove_dev.isra.12+0x22c/0x380) from [] (cpufreq_cpu_callback+0x48/0x5c) [] (cpufreq_cpu_callback+0x48/0x5c) from [] (notifier_call_chain+0x44/0x84) [] (notifier_call_chain+0x44/0x84) from [] (__cpu_notify+0x2c/0x48) [] (__cpu_notify+0x2c/0x48) from [] (_cpu_down+0x80/0x258) [] (_cpu_down+0x80/0x258) from [] (cpu_down+0x28/0x3c) [] (cpu_down+0x28/0x3c) from [] (store_online+0x30/0x74) [] (store_online+0x30/0x74) from [] (dev_attr_store+0x18/0x24) [] (dev_attr_store+0x18/0x24) from [] (sysfs_write_file+0x100/0x180) [] (sysfs_write_file+0x100/0x180) from [] (vfs_write+0xbc/0x184) [] (vfs_write+0xbc/0x184) from [] (SyS_write+0x40/0x68) [] (SyS_write+0x40/0x68) from [] (ret_fast_syscall+0x0/0x48) In gov_queue_work(), lock cpufreq_governor_lock before gov_queue_work, and unlock it after __gov_queue_work(). In this way, governor_enabled is guaranteed not changed in gov_queue_work(). Signed-off-by: Jane Li Acked-by: Viresh Kumar Reviewed-by: Dmitry Torokhov Signed-off-by: Rafael J. Wysocki Signed-off-by: Corinna Vinschen

Replace with globally

2018-11-29T16:49:05+00:00

This was entirely automated, using the script by Al: PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*' sed -i -e "s!$PATT!#include !" \ $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h) to do the replacement at the end of the merge window. Requested-by: Al Viro Signed-off-by: Linus Torvalds Signed-off-by: Moyster

format-security: move static strings to const

2017-12-05T17:06:11+00:00

While examining output from trial builds with -Wformat-security enabled, many strings were found that should be defined as "const", or as a char array instead of char pointer. This makes some static analysis easier, by producing fewer false positives. As these are all trivial changes, it seemed best to put them all in a single patch rather than chopping them up per maintainer. Link: http://lkml.kernel.org/r/20170405214711.GA5711@beast Signed-off-by: Kees Cook Acked-by: Jes Sorensen [runner.c] Cc: Tony Lindgren Cc: Russell King Cc: "Maciej W. Rozycki" Cc: Ralf Baechle Cc: Arnd Bergmann Cc: Greg Kroah-Hartman Cc: "Rafael J. Wysocki" Cc: Viresh Kumar Cc: Daniel Vetter Cc: Jani Nikula Cc: Sean Paul Cc: David Airlie Cc: Yisen Zhuang Cc: Salil Mehta Cc: Thomas Bogendoerfer Cc: Jiri Slaby Cc: Patrice Chotard Cc: "David S. Miller" Cc: James Hogan Cc: Paul Burton Cc: Matt Redfearn Cc: Paolo Bonzini Cc: Ingo Molnar Cc: Rasmus Villemoes Cc: Mugunthan V N Cc: Felipe Balbi Cc: Jarod Wilson Cc: Florian Westphal Cc: Antonio Quartulli Cc: Dmitry Torokhov Cc: Kejian Yan Cc: Daode Huang Cc: Qianqian Xie Cc: Philippe Reynes Cc: Colin Ian King Cc: Eric Dumazet Cc: Christian Gromm Cc: Andrey Shvetsov Cc: Jason Litzinger Cc: WANG Cong Signed-off-by: Andrew Morton

cpufreq: s3c2416: double free on driver init error path

2017-11-06T14:31:04+00:00

commit a69261e4470d680185a15f748d9cdafb37c57a33 upstream. The "goto err_armclk;" error path already does a clk_put(s3c_freq->hclk); so this is a double free. Fixes: 34ee55075265 ([CPUFREQ] Add S3C2416/S3C2450 cpufreq driver) Signed-off-by: Dan Carpenter Reviewed-by: Krzysztof Kozlowski Acked-by: Viresh Kumar Signed-off-by: Rafael J. Wysocki Signed-off-by: Willy Tarreau

cpufreq: conservative: Allow down_threshold to take values from 1 to 10

2017-11-06T14:19:13+00:00

commit b8e11f7d2791bd9320be1c6e772a60b2aa093e45 upstream. Commit 27ed3cd2ebf4 (cpufreq: conservative: Fix the logic in frequency decrease checking) removed the 10 point substraction when comparing the load against down_threshold but did not remove the related limit for the down_threshold value. As a result, down_threshold lower than 11 is not allowed even though values from 1 to 10 do work correctly too. The comment ("cannot be lower than 11 otherwise freq will not fall") also does not apply after removing the substraction. For this reason, allow down_threshold to take any value from 1 to 99 and fix the related comment. Fixes: 27ed3cd2ebf4 (cpufreq: conservative: Fix the logic in frequency decrease checking) Signed-off-by: Tomasz Wilczyński Acked-by: Viresh Kumar Cc: 3.10+ # 3.10+ Signed-off-by: Rafael J. Wysocki Signed-off-by: Willy Tarreau

drivers: cpufreq: checks to avoid kernel crash in cpufreq_interactive

2017-09-14T16:24:20+00:00

In cpufreq_governor_interactive, driver throws warning with WARN_ON for !tunables and event != CPUFREQ_GOV_POLICY_INIT. In case when tunables is NULL for event other than CPUFREQ_GOV_POLICY_INIT, kernel will crash as there is no safe check available before accessing tunables. So to handle such case and avoid the kernel crash, return -EINVAL if WARN_ON returns TRUE. Change-Id: I7a3a22d58e3c8a315a1cc1d31143649dc8807dee Signed-off-by: gaurav jindal

cpufreq: Fix and clean up show_cpuinfo_cur_freq()

2017-07-04T10:11:08+00:00

commit 9b4f603e7a9f4282aec451063ffbbb8bb410dcd9 upstream. There is a missing newline in show_cpuinfo_cur_freq(), so add it, but while at it clean that function up somewhat too. Signed-off-by: Rafael J. Wysocki Acked-by: Viresh Kumar Signed-off-by: Jiri Slaby Signed-off-by: Willy Tarreau

drivers: cpufreq: fix maybe-uninitialized warning

2017-05-23T17:21:31+00:00

drivers/cpufreq/cpufreq_stats.c: In function 'cpufreq_stat_notifier_policy': drivers/cpufreq/cpufreq_stats.c:588:6: warning: 'ret' may be used uninitialized in this function [-Wmaybe-uninitialized] int ret, count = 0, i; ^~~ Signed-off-by: Nathan Chancellor

Get rid of __cpuinit

2017-04-11T09:00:11+00:00

This commit is the result of find . -name '*.c' | xargs sed -i 's/ __cpuinit / /g' find . -name '*.c' | xargs sed -i 's/ __cpuexit / /g' find . -name '*.c' | xargs sed -i 's/ __cpuinitdata / /g' find . -name '*.c' | xargs sed -i 's/ __cpuinit$//g' find ./arch/ -name '*.h' | xargs sed -i 's/ __cpuinit//g' find . -name '*.c' | xargs sed -i 's/^__cpuinit //g' find . -name '*.c' | xargs sed -i 's/^__cpuinitdata //g' find . -name '*.c' | xargs sed -i 's/\*__cpuinit /\*/g' find . -name '*.c' | xargs sed -i 's/ __cpuinitconst / /g' find . -name '*.h' | xargs sed -i 's/ __cpuinit / /g' find . -name '*.h' | xargs sed -i 's/ __cpuinitdata / /g' git add . git reset include/linux/init.h git checkout -- include/linux/init.h based off : https://github.com/jollaman999/jolla-kernel_bullhead/commit/bc15db84a622eed7d61d3ece579b577154d0ec29

cpufreq: ondemand: Eliminate the deadband effect

2016-09-13T11:23:00+00:00

using the formula: Target frequency = C * load where C = policy->cpuinfo.max_freq / 100 Though, in many cases, the minimum available frequency is pretty high and the above calculation introduces a dead band from load 0 to 100 * policy->cpuinfo.min_freq / policy->cpuinfo.max_freq where the target frequency is always calculated to less than policy->cpuinfo.min_freq and the minimum frequency is selected. For example: on Intel i7-3770 @ 3.4GHz the policy->cpuinfo.min_freq = 1600000 and the policy->cpuinfo.max_freq = 3400000 (without turbo). Thus, the CPU starts to scale up at a load above 47. On quad core 1500MHz Krait the policy->cpuinfo.min_freq = 384000 and the policy->cpuinfo.max_freq = 1512000. Thus, the CPU starts to scale at load above 25. Change the calculation of target frequency to eliminate the above effect using the formula: Target frequency = A + B * load where A = policy->cpuinfo.min_freq and B = (policy->cpuinfo.max_freq - policy->cpuinfo->min_freq) / 100 This will map load values 0 to 100 linearly to cpuinfo.min_freq to cpuinfo.max_freq. Also, use the CPUFREQ_RELATION_C in __cpufreq_driver_target to select the closest frequency in frequency_table. This is necessary to avoid selection of minimum frequency only when load equals to 0. It will also help for selection of frequencies using a more 'fair' criterion. Tables below show the difference in selected frequency for specific values of load without and with this patch. On Intel i7-3770 @ 3.40GHz: Without With Load Target Selected Target Selected 0 0 1600000 1600000 1600000 5 170050 1600000 1690050 1700000 10 340100 1600000 1780100 1700000 15 510150 1600000 1870150 1900000 20 680200 1600000 1960200 2000000 25 850250 1600000 2050250 2100000 30 1020300 1600000 2140300 2100000 35 1190350 1600000 2230350 2200000 40 1360400 1600000 2320400 2400000 45 1530450 1600000 2410450 2400000 50 1700500 1900000 2500500 2500000 55 1870550 1900000 2590550 2600000 60 2040600 2100000 2680600 2600000 65 2210650 2400000 2770650 2800000 70 2380700 2400000 2860700 2800000 75 2550750 2600000 2950750 3000000 80 2720800 2800000 3040800 3000000 85 2890850 2900000 3130850 3100000 90 3060900 3100000 3220900 3300000 95 3230950 3300000 3310950 3300000 100 3401000 3401000 3401000 3401000 On ARM quad core 1500MHz Krait: Without With Load Target Selected Target Selected 0 0 384000 384000 384000 5 75600 384000 440400 486000 10 151200 384000 496800 486000 15 226800 384000 553200 594000 20 302400 384000 609600 594000 25 378000 384000 666000 702000 30 453600 486000 722400 702000 35 529200 594000 778800 810000 40 604800 702000 835200 810000 45 680400 702000 891600 918000 50 756000 810000 948000 918000 55 831600 918000 1004400 1026000 60 907200 918000 1060800 1026000 65 982800 1026000 1117200 1134000 70 1058400 1134000 1173600 1134000 75 1134000 1134000 1230000 1242000 80 1209600 1242000 1286400 1242000 85 1285200 1350000 1342800 1350000 90 1360800 1458000 1399200 1350000 95 1436400 1458000 1455600 1458000 100 1512000 1512000 1512000 1512000 Tested on Intel i7-3770 CPU @ 3.40GHz and on ARM quad core 1500MHz Krait (Android smartphone). Benchmarks on Intel i7 shows a performance improvement on low and medium work loads with lower power consumption. Specifics: Phoronix Linux Kernel Compilation 3.1: Time: -0.40%, energy: -0.07% Phoronix Apache: Time: -4.98%, energy: -2.35% Phoronix FFMPEG: Time: -6.29%, energy: -4.02% Also, running mp3 decoding (very low load) shows no differences with and without this patch. Signed-off-by: Stratos Karafotis Signed-off-by: Rafael J. Wysocki