[PATCH 5.5 36/46] iwlwifi: yoyo: dont add TLV offset when reading FIFOs

From: Greg Kroah-Hartman
Date: Tue Apr 07 2020 - 06:26:03 EST


From: Mordechay Goodstein <mordechay.goodstein@xxxxxxxxx>

commit a5688e600e78f9fc68102bf0fe5c797fc2826abe upstream.

The TLV offset is only used to read registers, while the offset used for
the FIFO addresses are hard coded in the driver and not given by the
TLV.

If we try to apply the TLV offset when reading the FIFOs, we'll read
from invalid addresses, causing the driver to hang.

Signed-off-by: Mordechay Goodstein <mordechay.goodstein@xxxxxxxxx>
Fixes: 8d7dea25ada7 ("iwlwifi: dbg_ini: implement Rx fifos dump")
Signed-off-by: Luca Coelho <luciano.coelho@xxxxxxxxx>
Link: https://lore.kernel.org/r/iwlwifi.20200306151129.fbab869c26fa.I4ddac20d02f9bce41855a816aa6855c89bc3874e@changeid
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/net/wireless/intel/iwlwifi/fw/dbg.c | 10 +++-------
1 file changed, 3 insertions(+), 7 deletions(-)

--- a/drivers/net/wireless/intel/iwlwifi/fw/dbg.c
+++ b/drivers/net/wireless/intel/iwlwifi/fw/dbg.c
@@ -8,7 +8,7 @@
* Copyright(c) 2008 - 2014 Intel Corporation. All rights reserved.
* Copyright(c) 2013 - 2015 Intel Mobile Communications GmbH
* Copyright(c) 2015 - 2017 Intel Deutschland GmbH
- * Copyright(c) 2018 - 2019 Intel Corporation
+ * Copyright(c) 2018 - 2020 Intel Corporation
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of version 2 of the GNU General Public License as
@@ -31,7 +31,7 @@
* Copyright(c) 2005 - 2014 Intel Corporation. All rights reserved.
* Copyright(c) 2013 - 2015 Intel Mobile Communications GmbH
* Copyright(c) 2015 - 2017 Intel Deutschland GmbH
- * Copyright(c) 2018 - 2019 Intel Corporation
+ * Copyright(c) 2018 - 2020 Intel Corporation
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
@@ -1407,11 +1407,7 @@ static int iwl_dump_ini_rxf_iter(struct
goto out;
}

- /*
- * region register have absolute value so apply rxf offset after
- * reading the registers
- */
- offs += rxf_data.offset;
+ offs = rxf_data.offset;

/* Lock fence */
iwl_write_prph_no_grab(fwrt->trans, RXF_SET_FENCE_MODE + offs, 0x1);