The kthread_run() function returns error pointers so the max3421_hcd->spi_thread pointer can be either error pointers or NULL. Check for both before dereferencing it. Fixes: 05dfa5c9bc37 ("usb: host: max3421-hcd: fix "spi_rd8" uses dynamic stack allocation warning") Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> --- drivers/usb/host/max3421-hcd.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/usb/host/max3421-hcd.c b/drivers/usb/host/max3421-hcd.c index dcf31a592f5d..4b5f03f683f7 100644 --- a/drivers/usb/host/max3421-hcd.c +++ b/drivers/usb/host/max3421-hcd.c @@ -1916,7 +1916,7 @@ max3421_probe(struct spi_device *spi) if (hcd) { kfree(max3421_hcd->tx); kfree(max3421_hcd->rx); - if (max3421_hcd->spi_thread) + if (!IS_ERR_OR_NULL(max3421_hcd->spi_thread)) kthread_stop(max3421_hcd->spi_thread); usb_put_hcd(hcd); } -- 2.47.2