remoteproc: core: Remove state checking before calling rproc_boot()
There is no mutex protection of the state checking before rproc_boot(), which can't guarantee there is no another instance is trying to do same operation. Consider two instances case: Instance1: echo start > /sys/class/remoteproc/remoteproc0/state Instance2: echo start > /sys/class/remoteproc/remoteproc0/state ... Instance2: echo stop > /sys/class/remoteproc/remoteproc0/state ... Instance1: echo stop > /sys/class/remoteproc/remoteproc0/state The one issue is that the instance2 case may success when 'start' happens at same time as instance1, then rproc->power = 2; Or it may fail with -BUSY, then rproc->power = 1; which is uncertain. The another issue is for 'stop' operation, if the rproc->power = 1, when instance2 'stop' the remoteproc the instance1 will be impacted for it still needs the service at that time. The reference counter rproc->power is used to manage state changing and there is mutex protection in each operation function for multi instance case. So remove this state checking in rproc_cdev_write() and state_store() for 'start' operation, just let reference counter rproc->power to manage the behaviors. Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com> Link: https://lore.kernel.org/r/1648434012-16655-2-git-send-email-shengjiu.wang@nxp.comSigned-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
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