Under heavy load it is likely that the controller is done with its own task but the thread unlocking the wait is not scheduled in time. Increasing IFC_TIMEOUT_MSECS allows the controller to respond within allowable timeslice of 1 sec

fsl,ifc-nand 7e800000.nand: Controller is not responding main/smp_fsm.c:1884 <inrcu: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P116/2:b..l (detected by 1, t=2102 jiffies, g=7729, q=754) task:irq/31-arm-irq1 state:D stack: 0 pid: 116 ppid: 2 flags:0x00000000 [<8064b97f>] (__schedule) from [<8064bb01>] (schedule+0x8d/0xc2) [<8064bb01>] (schedule) from [<8064dacd>] [<8064dacd>] (rt_mutex_slowlock_block.constprop.0) from [<8064db57>] [<8064db57>] (__rt_mutex_slowlock.constprop.0) from [<8064dbf7>] [<8064dbf7>] (rt_mutex_slowlock.constprop.0) from [<804b2047>] [<804b2047>] (nand_get_device) from [<804b5335>] (nand_write_oob+0x1b/0x4a) [<804b5335>] (nand_write_oob) from [<804a3585>] (mtd_write+0x41/0x5c) [<804a3585>] (mtd_write) from [<804c1d47>] (ubi_io_write+0x17f/0x22c) [<804c1d47>] (ubi_io_write) from [<804c047b>] (ubi_eba_write_leb+0x5b/0x1d0)

Cc: stable@vger.kernel.org Signed-off-by: Ronald Monthero debug.penguin32@gmail.com --- drivers/mtd/nand/raw/fsl_ifc_nand.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/mtd/nand/raw/fsl_ifc_nand.c b/drivers/mtd/nand/raw/fsl_ifc_nand.c index 20bb1e0cb5eb..42f8ea46b6a8 100644 --- a/drivers/mtd/nand/raw/fsl_ifc_nand.c +++ b/drivers/mtd/nand/raw/fsl_ifc_nand.c @@ -21,7 +21,7 @@

#define ERR_BYTE 0xFF /* Value returned for read bytes when read failed */ -#define IFC_TIMEOUT_MSECS 500 /* Maximum number of mSecs to wait +#define IFC_TIMEOUT_MSECS 1000 /* Maximum number of mSecs to wait for IFC NAND Machine */

struct fsl_ifc_ctrl;