Sebastian Andrzej Siewior 817a7c9967 scsi: message: fusion: Remove in_interrupt() usage in mptsas_cleanup_fw_event_q() ... mptsas_cleanup_fw_event_q() uses in_interrupt() to determine if it is safe to cancel a worker item. Aside of that in_interrupt() is deprecated as it does not provide what the name suggests. It covers more than hard/soft interrupt servicing context and is semantically ill defined. Looking closer there are a few problems with the current construct: - It could be invoked from an interrupt handler / non-blocking context because cancel_delayed_work() has no such restriction. Also, mptsas_free_fw_event() has no such restriction. - The list is accessed unlocked. It may dequeue a valid work-item but at the time of invoking cancel_delayed_work() the memory may be released or reused because the worker has already run. mptsas_cleanup_fw_event_q() is invoked via mptsas_shutdown() which is always invoked from preemtible context on device shutdown. It is also invoked via mptsas_ioc_reset(, MPT_IOC_POST_RESET) which is a MptResetHandlers callback. The only caller here are mpt_SoftResetHandler(), mpt_HardResetHandler() and mpt_Soft_Hard_ResetHandler(). All these functions have a `sleepFlag' argument and each caller uses caller uses `CAN_SLEEP' here and according to current documentation: | @sleepFlag: Indicates if sleep or schedule must be called So it is safe to sleep. Add mptsas_hotplug_event::users member. Initialize it to one by default so mptsas_free_fw_event() will free the memory. mptsas_cleanup_fw_event_q() will increment its value for items it dequeues and then it may keep a pointer after dropping the lock. Invoke cancel_delayed_work_sync() to cancel the work item and wait if the worker is currently busy. Free the memory afterwards since it owns the last reference to it. Link: https://lore.kernel.org/r/20201126132952.2287996-15-bigeasy@linutronix.de Cc: Sathya Prakash <sathya.prakash@broadcom.com> Cc: Sreekanth Reddy <sreekanth.reddy@broadcom.com> Cc: Suganath Prabu Subramani <suganath-prabu.subramani@broadcom.com> Cc: MPT-FusionLinux.pdl@broadcom.com Reviewed-by: Daniel Wagner <dwagner@suse.de> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>		2020-12-01 00:03:54 -05:00
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fusion	scsi: message: fusion: Remove in_interrupt() usage in mptsas_cleanup_fw_event_q()	2020-12-01 00:03:54 -05:00
Makefile	treewide: Add SPDX license identifier - Makefile/Kconfig	2019-05-21 10:50:46 +02:00