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Revision b90d72a6bfdb5e5c62cd223a8cdf4045bfbcb94d authored by Will Deacon on 12 January 2021, 22:18:55 UTC, committed by Catalin Marinas on 13 January 2021, 15:08:41 UTC 
Revert "arm64: Enable perf events based hard lockup detector"
 
This reverts commit 367c820ef08082e68df8a3bc12e62393af21e4b5.

lockup_detector_init() makes heavy use of per-cpu variables and must be
called with preemption disabled. Usually, it's handled early during boot
in kernel_init_freeable(), before SMP has been initialised.

Since we do not know whether or not our PMU interrupt can be signalled
as an NMI until considerably later in the boot process, the Arm PMU
driver attempts to re-initialise the lockup detector off the back of a
device_initcall(). Unfortunately, this is called from preemptible
context and results in the following splat:

  | BUG: using smp_processor_id() in preemptible [00000000] code: swapper/0/1
  | caller is debug_smp_processor_id+0x20/0x2c
  | CPU: 2 PID: 1 Comm: swapper/0 Not tainted 5.10.0+ #276
  | Hardware name: linux,dummy-virt (DT)
  | Call trace:
  |   dump_backtrace+0x0/0x3c0
  |   show_stack+0x20/0x6c
  |   dump_stack+0x2f0/0x42c
  |   check_preemption_disabled+0x1cc/0x1dc
  |   debug_smp_processor_id+0x20/0x2c
  |   hardlockup_detector_event_create+0x34/0x18c
  |   hardlockup_detector_perf_init+0x2c/0x134
  |   watchdog_nmi_probe+0x18/0x24
  |   lockup_detector_init+0x44/0xa8
  |   armv8_pmu_driver_init+0x54/0x78
  |   do_one_initcall+0x184/0x43c
  |   kernel_init_freeable+0x368/0x380
  |   kernel_init+0x1c/0x1cc
  |   ret_from_fork+0x10/0x30

Rather than bodge this with raw_smp_processor_id() or randomly disabling
preemption, simply revert the culprit for now until we figure out how to
do this properly.

Reported-by: Lecopzer Chen <lecopzer.chen@mediatek.com>
Signed-off-by: Will Deacon <will@kernel.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: Sumit Garg <sumit.garg@linaro.org>
Cc: Alexandru Elisei <alexandru.elisei@arm.com>
Link: https://lore.kernel.org/r/20201221162249.3119-1-lecopzer.chen@mediatek.com
Link: https://lore.kernel.org/r/20210112221855.10666-1-will@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
1 parent df06824
Raw File
da7219-aad.h 
/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
 * da7219-aad.h - DA7322 ASoC Codec AAD Driver Platform Data
 *
 * Copyright (c) 2015 Dialog Semiconductor Ltd.
 *
 * Author: Adam Thomson <Adam.Thomson.Opensource@diasemi.com>
 */

#ifndef __DA7219_AAD_PDATA_H
#define __DA7219_AAD_PDATA_H

enum da7219_aad_micbias_pulse_lvl {
	DA7219_AAD_MICBIAS_PULSE_LVL_OFF = 0,
	DA7219_AAD_MICBIAS_PULSE_LVL_2_8V = 6,
	DA7219_AAD_MICBIAS_PULSE_LVL_2_9V,
};

enum da7219_aad_btn_cfg {
	DA7219_AAD_BTN_CFG_2MS = 1,
	DA7219_AAD_BTN_CFG_5MS,
	DA7219_AAD_BTN_CFG_10MS,
	DA7219_AAD_BTN_CFG_50MS,
	DA7219_AAD_BTN_CFG_100MS,
	DA7219_AAD_BTN_CFG_200MS,
	DA7219_AAD_BTN_CFG_500MS,
};

enum da7219_aad_mic_det_thr {
	DA7219_AAD_MIC_DET_THR_200_OHMS = 0,
	DA7219_AAD_MIC_DET_THR_500_OHMS,
	DA7219_AAD_MIC_DET_THR_750_OHMS,
	DA7219_AAD_MIC_DET_THR_1000_OHMS,
};

enum da7219_aad_jack_ins_deb {
	DA7219_AAD_JACK_INS_DEB_5MS = 0,
	DA7219_AAD_JACK_INS_DEB_10MS,
	DA7219_AAD_JACK_INS_DEB_20MS,
	DA7219_AAD_JACK_INS_DEB_50MS,
	DA7219_AAD_JACK_INS_DEB_100MS,
	DA7219_AAD_JACK_INS_DEB_200MS,
	DA7219_AAD_JACK_INS_DEB_500MS,
	DA7219_AAD_JACK_INS_DEB_1S,
};

enum da7219_aad_jack_det_rate {
	DA7219_AAD_JACK_DET_RATE_32_64MS = 0,
	DA7219_AAD_JACK_DET_RATE_64_128MS,
	DA7219_AAD_JACK_DET_RATE_128_256MS,
	DA7219_AAD_JACK_DET_RATE_256_512MS,
};

enum da7219_aad_jack_rem_deb {
	DA7219_AAD_JACK_REM_DEB_1MS = 0,
	DA7219_AAD_JACK_REM_DEB_5MS,
	DA7219_AAD_JACK_REM_DEB_10MS,
	DA7219_AAD_JACK_REM_DEB_20MS,
};

enum da7219_aad_btn_avg {
	DA7219_AAD_BTN_AVG_1 = 0,
	DA7219_AAD_BTN_AVG_2,
	DA7219_AAD_BTN_AVG_4,
	DA7219_AAD_BTN_AVG_8,
};

enum da7219_aad_adc_1bit_rpt {
	DA7219_AAD_ADC_1BIT_RPT_1 = 0,
	DA7219_AAD_ADC_1BIT_RPT_2,
	DA7219_AAD_ADC_1BIT_RPT_4,
	DA7219_AAD_ADC_1BIT_RPT_8,
};

struct da7219_aad_pdata {
	int irq;

	enum da7219_aad_micbias_pulse_lvl micbias_pulse_lvl;
	u32 micbias_pulse_time;
	enum da7219_aad_btn_cfg btn_cfg;
	enum da7219_aad_mic_det_thr mic_det_thr;
	enum da7219_aad_jack_ins_deb jack_ins_deb;
	enum da7219_aad_jack_det_rate jack_det_rate;
	enum da7219_aad_jack_rem_deb jack_rem_deb;

	u8 a_d_btn_thr;
	u8 d_b_btn_thr;
	u8 b_c_btn_thr;
	u8 c_mic_btn_thr;

	enum da7219_aad_btn_avg btn_avg;
	enum da7219_aad_adc_1bit_rpt adc_1bit_rpt;
};

#endif /* __DA7219_AAD_PDATA_H */
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