Will Deacon b90d72a6bf Revert "arm64: Enable perf events based hard lockup detector" ... This reverts commit 367c820ef0. 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>		2021-01-13 15:08:41 +00:00
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hisilicon	drivers/perf: hisi: Add identifier sysfs file	2020-11-25 15:10:35 +00:00
Kconfig	…
Makefile	…
arm-cci.c	…
arm-ccn.c	…
arm-cmn.c	…
arm_dmc620_pmu.c	…
arm_dsu_pmu.c	…
arm_pmu.c	Revert "arm64: Enable perf events based hard lockup detector"	2021-01-13 15:08:41 +00:00
arm_pmu_acpi.c	…
arm_pmu_platform.c	…
arm_smmuv3_pmu.c	perf/smmuv3: Support sysfs identifier file	2020-11-25 15:10:35 +00:00
arm_spe_pmu.c	…
fsl_imx8_ddr_perf.c	perf/imx_ddr: Add system PMU identifier for userspace	2020-12-09 14:14:02 +00:00
qcom_l2_pmu.c	…
qcom_l3_pmu.c	…
thunderx2_pmu.c	…
xgene_pmu.c	…