firmware_loading_complete is used to synchronize operations on rproc while asynchronous firmware loading is in progress. However, rproc_boot() no longer waits on firmware_loading_complete. Hence drop this completion variable altogether and handle the race between rproc_del() and rproc_boot() using new state RPROC_DELETED.
The request_firmware_nowait() will hold the reference to rproc device by using a get_device()/put_device(), so the rproc struct will remain valid even when we return from rproc_del() before the asynchronous call to rproc_fw_config_virtio() completes. CC: Loic Pallardy <loic.palla...@st.com> CC: Bjorn Andersson <bjorn.anders...@linaro.org> Signed-off-by: Sarangdhar Joshi <spjo...@codeaurora.org> --- The current patch series is a v2 version of original patch listed at https://lkml.org/lkml/2016/12/16/534 Changes from v1: * Add new RPROC_DELETED state * Use the new state RPROC_DELETED to handle race between rproc_del() and rproc_boot() drivers/remoteproc/remoteproc_core.c | 22 +++++++++++----------- include/linux/remoteproc.h | 2 -- 2 files changed, 11 insertions(+), 13 deletions(-) diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c index 78200a7..f58e634 100644 --- a/drivers/remoteproc/remoteproc_core.c +++ b/drivers/remoteproc/remoteproc_core.c @@ -975,17 +975,12 @@ static void rproc_fw_config_virtio(const struct firmware *fw, void *context) rproc_boot(rproc); release_firmware(fw); - /* allow rproc_del() contexts, if any, to proceed */ - complete_all(&rproc->firmware_loading_complete); } static int rproc_add_virtio_devices(struct rproc *rproc) { int ret; - /* rproc_del() calls must wait until async loader completes */ - init_completion(&rproc->firmware_loading_complete); - /* * We must retrieve early virtio configuration info from * the firmware (e.g. whether to register a virtio device, @@ -997,10 +992,8 @@ static int rproc_add_virtio_devices(struct rproc *rproc) ret = request_firmware_nowait(THIS_MODULE, FW_ACTION_HOTPLUG, rproc->firmware, &rproc->dev, GFP_KERNEL, rproc, rproc_fw_config_virtio); - if (ret < 0) { + if (ret < 0) dev_err(&rproc->dev, "request_firmware_nowait err: %d\n", ret); - complete_all(&rproc->firmware_loading_complete); - } return ret; } @@ -1097,6 +1090,12 @@ static int __rproc_boot(struct rproc *rproc) return ret; } + if (rproc->state == RPROC_DELETED) { + ret = -ENODEV; + dev_err(dev, "can't boot deleted rproc %s\n", rproc->name); + goto unlock_mutex; + } + /* skip the boot process if rproc is already powered up */ if (atomic_inc_return(&rproc->power) > 1) { ret = 0; @@ -1481,14 +1480,15 @@ int rproc_del(struct rproc *rproc) if (!rproc) return -EINVAL; - /* if rproc is just being registered, wait */ - wait_for_completion(&rproc->firmware_loading_complete); - /* if rproc is marked always-on, rproc_add() booted it */ /* TODO: make sure this works with rproc->power > 1 */ if (rproc->auto_boot) rproc_shutdown(rproc); + mutex_lock(&rproc->lock); + rproc->state = RPROC_DELETED; + mutex_unlock(&rproc->lock); + rproc_delete_debug_dir(rproc); /* the rproc is downref'ed as soon as it's removed from the klist */ diff --git a/include/linux/remoteproc.h b/include/linux/remoteproc.h index 25a8c37..26328c4 100644 --- a/include/linux/remoteproc.h +++ b/include/linux/remoteproc.h @@ -399,7 +399,6 @@ enum rproc_crash_type { * @num_traces: number of trace buffers * @carveouts: list of physically contiguous memory allocations * @mappings: list of iommu mappings we initiated, needed on shutdown - * @firmware_loading_complete: marks e/o asynchronous firmware loading * @bootaddr: address of first instruction to boot rproc with (optional) * @rvdevs: list of remote virtio devices * @subdevs: list of subdevices, to following the running state @@ -430,7 +429,6 @@ struct rproc { int num_traces; struct list_head carveouts; struct list_head mappings; - struct completion firmware_loading_complete; u32 bootaddr; struct list_head rvdevs; struct list_head subdevs; -- The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project
