From b9693304b7133b81741add5bfb56f022596df012 Mon Sep 17 00:00:00 2001 From: Shengjiu Wang Date: Fri, 30 Sep 2022 15:50:16 +0800 Subject: [PATCH] remoteproc: imx_dsp_rproc: Add mutex protection for workqueue commit 47e6ab07018edebf94ce873cf50a05ec76ff2dde upstream. The workqueue may execute late even after remoteproc is stopped or stopping, some resources (rpmsg device and endpoint) have been released in rproc_stop_subdevices(), then rproc_vq_interrupt() accessing these resources will cause kennel dump. Call trace: virtqueue_add_split+0x1ac/0x560 virtqueue_add_inbuf+0x4c/0x60 rpmsg_recv_done+0x15c/0x294 vring_interrupt+0x6c/0xa4 rproc_vq_interrupt+0x30/0x50 imx_dsp_rproc_vq_work+0x24/0x40 [imx_dsp_rproc] process_one_work+0x1d0/0x354 worker_thread+0x13c/0x470 kthread+0x154/0x160 ret_from_fork+0x10/0x20 Add mutex protection in imx_dsp_rproc_vq_work(), if the state is not running, then just skip calling rproc_vq_interrupt(). Also the flush workqueue operation can't be added in rproc stop for the same reason. The call sequence is rproc_shutdown -> rproc_stop ->rproc_stop_subdevices ->rproc->ops->stop() ->imx_dsp_rproc_stop ->flush_work -> rproc_vq_interrupt The resource needed by rproc_vq_interrupt has been released in rproc_stop_subdevices, so flush_work is not safe to be called in imx_dsp_rproc_stop. Fixes: ec0e5549f358 ("remoteproc: imx_dsp_rproc: Add remoteproc driver for DSP on i.MX") Signed-off-by: Shengjiu Wang Reviewed-by: Peng Fan Cc: stable Link: https://lore.kernel.org/r/1664524216-19949-1-git-send-email-shengjiu.wang@nxp.com Signed-off-by: Mathieu Poirier Signed-off-by: Greg Kroah-Hartman --- drivers/remoteproc/imx_dsp_rproc.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/drivers/remoteproc/imx_dsp_rproc.c b/drivers/remoteproc/imx_dsp_rproc.c index 899aa8d..95da1cb 100644 --- a/drivers/remoteproc/imx_dsp_rproc.c +++ b/drivers/remoteproc/imx_dsp_rproc.c @@ -347,9 +347,6 @@ static int imx_dsp_rproc_stop(struct rproc *rproc) struct device *dev = rproc->dev.parent; int ret = 0; - /* Make sure work is finished */ - flush_work(&priv->rproc_work); - if (rproc->state == RPROC_CRASHED) { priv->flags &= ~REMOTE_IS_READY; return 0; @@ -432,9 +429,18 @@ static void imx_dsp_rproc_vq_work(struct work_struct *work) { struct imx_dsp_rproc *priv = container_of(work, struct imx_dsp_rproc, rproc_work); + struct rproc *rproc = priv->rproc; + + mutex_lock(&rproc->lock); + + if (rproc->state != RPROC_RUNNING) + goto unlock_mutex; rproc_vq_interrupt(priv->rproc, 0); rproc_vq_interrupt(priv->rproc, 1); + +unlock_mutex: + mutex_unlock(&rproc->lock); } /** -- 2.7.4