From: Suman Anna s-anna@ti.com
[ Upstream commit 880a66e026fbe6a17cd59fe0ee942bbad62a6c26 ]
The PRU firmware interrupt mappings are configured and unconfigured in .start() and .stop() callbacks respectively using the variables 'evt_count' and a 'mapped_irq' pointer. These variables are modified only during these callbacks but are not re-initialized/reset properly during unwind or failure paths. These stale values caused a kernel crash while stopping a PRU remoteproc running a different firmware with no events on a subsequent run after a previous run that was running a firmware with events.
Fix this crash by ensuring that the evt_count is 0 and the mapped_irq pointer is set to NULL in pru_dispose_irq_mapping(). Also, reset these variables properly during any failures in the .start() callback. While at this, the pru_dispose_irq_mapping() callsites are all made to look the same, moving any conditional logic to inside the function.
Reviewed-by: Mathieu Poirier mathieu.poirier@linaro.org Fixes: c75c9fdac66e ("remoteproc: pru: Add support for PRU specific interrupt configuration") Reported-by: Vignesh Raghavendra vigneshr@ti.com Signed-off-by: Suman Anna s-anna@ti.com Link: https://lore.kernel.org/r/20210407155641.5501-4-s-anna@ti.com Signed-off-by: Bjorn Andersson bjorn.andersson@linaro.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/remoteproc/pru_rproc.c | 22 +++++++++++++++++----- 1 file changed, 17 insertions(+), 5 deletions(-)
diff --git a/drivers/remoteproc/pru_rproc.c b/drivers/remoteproc/pru_rproc.c index dcd5ea0d1f37..549ed3fed625 100644 --- a/drivers/remoteproc/pru_rproc.c +++ b/drivers/remoteproc/pru_rproc.c @@ -266,12 +266,17 @@ static void pru_rproc_create_debug_entries(struct rproc *rproc)
static void pru_dispose_irq_mapping(struct pru_rproc *pru) { - while (pru->evt_count--) { + if (!pru->mapped_irq) + return; + + while (pru->evt_count) { + pru->evt_count--; if (pru->mapped_irq[pru->evt_count] > 0) irq_dispose_mapping(pru->mapped_irq[pru->evt_count]); }
kfree(pru->mapped_irq); + pru->mapped_irq = NULL; }
/* @@ -307,8 +312,10 @@ static int pru_handle_intrmap(struct rproc *rproc) pru->evt_count = rsc->num_evts; pru->mapped_irq = kcalloc(pru->evt_count, sizeof(unsigned int), GFP_KERNEL); - if (!pru->mapped_irq) + if (!pru->mapped_irq) { + pru->evt_count = 0; return -ENOMEM; + }
/* * parse and fill in system event to interrupt channel and @@ -317,13 +324,19 @@ static int pru_handle_intrmap(struct rproc *rproc) * corresponding sibling PRUSS INTC node. */ parent = of_get_parent(dev_of_node(pru->dev)); - if (!parent) + if (!parent) { + kfree(pru->mapped_irq); + pru->mapped_irq = NULL; + pru->evt_count = 0; return -ENODEV; + }
irq_parent = of_get_child_by_name(parent, "interrupt-controller"); of_node_put(parent); if (!irq_parent) { kfree(pru->mapped_irq); + pru->mapped_irq = NULL; + pru->evt_count = 0; return -ENODEV; }
@@ -398,8 +411,7 @@ static int pru_rproc_stop(struct rproc *rproc) pru_control_write_reg(pru, PRU_CTRL_CTRL, val);
/* dispose irq mapping - new firmware can provide new mapping */ - if (pru->mapped_irq) - pru_dispose_irq_mapping(pru); + pru_dispose_irq_mapping(pru);
return 0; }