History log of /linux-master/drivers/cpufreq/amd-pstate-ut.c
Revision Date Author Comments
# 60dd2838 18-Aug-2023 Swapnil Sapkal <swapnil.sapkal@amd.com>

cpufreq: amd-pstate-ut: Fix kernel panic when loading the driver

After loading the amd-pstate-ut driver, amd_pstate_ut_check_perf()
and amd_pstate_ut_check_freq() use cpufreq_cpu_get() to get the policy
of the CPU and mark it as busy.

In these functions, cpufreq_cpu_put() should be used to release the
policy, but it is not, so any other entity trying to access the policy
is blocked indefinitely.

One such scenario is when amd_pstate mode is changed, leading to the
following splat:

[ 1332.103727] INFO: task bash:2929 blocked for more than 120 seconds.
[ 1332.110001] Not tainted 6.5.0-rc2-amd-pstate-ut #5
[ 1332.115315] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 1332.123140] task:bash state:D stack:0 pid:2929 ppid:2873 flags:0x00004006
[ 1332.123143] Call Trace:
[ 1332.123145] <TASK>
[ 1332.123148] __schedule+0x3c1/0x16a0
[ 1332.123154] ? _raw_read_lock_irqsave+0x2d/0x70
[ 1332.123157] schedule+0x6f/0x110
[ 1332.123160] schedule_timeout+0x14f/0x160
[ 1332.123162] ? preempt_count_add+0x86/0xd0
[ 1332.123165] __wait_for_common+0x92/0x190
[ 1332.123168] ? __pfx_schedule_timeout+0x10/0x10
[ 1332.123170] wait_for_completion+0x28/0x30
[ 1332.123173] cpufreq_policy_put_kobj+0x4d/0x90
[ 1332.123177] cpufreq_policy_free+0x157/0x1d0
[ 1332.123178] ? preempt_count_add+0x58/0xd0
[ 1332.123180] cpufreq_remove_dev+0xb6/0x100
[ 1332.123182] subsys_interface_unregister+0x114/0x120
[ 1332.123185] ? preempt_count_add+0x58/0xd0
[ 1332.123187] ? __pfx_amd_pstate_change_driver_mode+0x10/0x10
[ 1332.123190] cpufreq_unregister_driver+0x3b/0xd0
[ 1332.123192] amd_pstate_change_driver_mode+0x1e/0x50
[ 1332.123194] store_status+0xe9/0x180
[ 1332.123197] dev_attr_store+0x1b/0x30
[ 1332.123199] sysfs_kf_write+0x42/0x50
[ 1332.123202] kernfs_fop_write_iter+0x143/0x1d0
[ 1332.123204] vfs_write+0x2df/0x400
[ 1332.123208] ksys_write+0x6b/0xf0
[ 1332.123210] __x64_sys_write+0x1d/0x30
[ 1332.123213] do_syscall_64+0x60/0x90
[ 1332.123216] ? fpregs_assert_state_consistent+0x2e/0x50
[ 1332.123219] ? exit_to_user_mode_prepare+0x49/0x1a0
[ 1332.123223] ? irqentry_exit_to_user_mode+0xd/0x20
[ 1332.123225] ? irqentry_exit+0x3f/0x50
[ 1332.123226] ? exc_page_fault+0x8e/0x190
[ 1332.123228] entry_SYSCALL_64_after_hwframe+0x6e/0xd8
[ 1332.123232] RIP: 0033:0x7fa74c514a37
[ 1332.123234] RSP: 002b:00007ffe31dd0788 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
[ 1332.123238] RAX: ffffffffffffffda RBX: 0000000000000008 RCX: 00007fa74c514a37
[ 1332.123239] RDX: 0000000000000008 RSI: 000055e27c447aa0 RDI: 0000000000000001
[ 1332.123241] RBP: 000055e27c447aa0 R08: 00007fa74c5d1460 R09: 000000007fffffff
[ 1332.123242] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000008
[ 1332.123244] R13: 00007fa74c61a780 R14: 00007fa74c616600 R15: 00007fa74c615a00
[ 1332.123247] </TASK>

Fix this by calling cpufreq_cpu_put() wherever necessary.

Fixes: 14eb1c96e3a3 ("cpufreq: amd-pstate: Add test module for amd-pstate driver")
Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>
Reviewed-by: Meng Li <li.meng@amd.com>
Reviewed-by: Wyes Karny <wyes.karny@amd.com>
Suggested-by: Wyes Karny <wyes.karny@amd.com>
Signed-off-by: Swapnil Sapkal <swapnil.sapkal@amd.com>
[ rjw: Subject and changelog edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>


# 8d6e5e82 18-Aug-2023 Swapnil Sapkal <swapnil.sapkal@amd.com>

cpufreq: amd-pstate-ut: Remove module parameter access

In amd-pstate-ut, shared memory-based systems call
get_shared_mem() as part of amd_pstate_ut_check_enabled()
function. This function was written when CONFIG_X86_AMD_PSTATE
was tristate config and amd_pstate can be built as a module.

Currently CONFIG_X86_AMD_PSTATE is a boolean config and module
parameter shared_mem is removed. But amd-pstate-ut code still
accesses this module parameter. Remove those accesses.

Fixes: 456ca88d8a52 ("cpufreq: amd-pstate: change amd-pstate driver to be built-in type")
Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>
Reviewed-by: Meng Li <li.meng@amd.com>
Reviewed-by: Wyes Karny <wyes.karny@amd.com>
Suggested-by: Wyes Karny <wyes.karny@amd.com>
Signed-off-by: Swapnil Sapkal <swapnil.sapkal@amd.com>
[ rjw: Subject edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>


# d3dec5bb 02-Aug-2023 Meng Li <li.meng@amd.com>

cpufreq: amd-pstate-ut: Modify the function to get the highest_perf value

The previous function amd_get_highest_perf() will be deprecated.
It can only return 166 or 255 by cpuinfo. For platforms that
support preferred core, the value of highest perf can be between
166 and 255. Therefore, it will cause amd-pstate-ut to fail when
run amd_pstate_ut_check_perf().

Signed-off-by: Meng Li <li.meng@amd.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>


# 2dfb010d 13-Nov-2022 Meng Li <li.meng@amd.com>

cpufreq: amd-pstate: fix spdxcheck warnings for amd-pstate-ut.c

spdxcheck warnings: (new ones prefixed by >>)
>> drivers/cpufreq/amd-pstate-ut.c: 1:28 Invalid License ID:
GPL-1.0-or-later
drivers/spi/spi-gxp.c: 1:35 Invalid token: =or-later

Signed-off-by: Meng Li <li.meng@amd.com>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>


# ce29a148 05-Sep-2022 Meng Li <li.meng@amd.com>

cpufreq: amd-pstate: modify type in argument 2 for filp_open

Modify restricted FMODE_PREAD to experted int O_RDONLY to
fix the sparse warnings below:
sparse warnings: (new ones prefixed by >>)
>> drivers/cpufreq/amd-pstate-ut.c:74:40: sparse: sparse: incorrect type
>> in argument 2 (different base types) @@ expected int @@ got
>> restricted fmode_t [usertype] @@
drivers/cpufreq/amd-pstate-ut.c:74:40: sparse: expected int
drivers/cpufreq/amd-pstate-ut.c:74:40: sparse: got restricted
fmode_t [usertype]

Signed-off-by: Meng Li <li.meng@amd.com>
Reported-by: kernel test robot <lkp@intel.com>
Acked-by: Huang Rui <ray.huang@amd.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>


# 14eb1c96 16-Aug-2022 Meng Li <li.meng@amd.com>

cpufreq: amd-pstate: Add test module for amd-pstate driver

Add amd-pstate-ut test module, this module is used by kselftest
to unit test amd-pstate functionality. This module will be
expected by some of selftests to be present and loaded.

Signed-off-by: Meng Li <li.meng@amd.com>
Acked-by: Huang Rui <ray.huang@amd.com>
Reviewed-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>