From: Luca Coelho <luciano.coelho@xxxxxxxxx> In iwl_dbgfs_mem_read(), the len variable may become negative and is compared to < 0 (an error case). Comparing size_t (which is unsigned) to < 0 causes a warning on certain platforms (like i386): drivers/net/wireless/intel/iwlwifi/mvm/debugfs.c:1561:5-8: WARNING: Unsigned expression compared with zero: len < 0 To prevent that, use ssize_t for len instead. Fixes: commit 2b55f43f8e47 ("iwlwifi: mvm: Add mem debugfs entry") Reported-by: kbuild test robot <fengguang.wu@xxxxxxxxx> Signed-off-by: Luca Coelho <luciano.coelho@xxxxxxxxx> --- drivers/net/wireless/intel/iwlwifi/mvm/debugfs.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/debugfs.c b/drivers/net/wireless/intel/iwlwifi/mvm/debugfs.c index 539d718..06805a6 100644 --- a/drivers/net/wireless/intel/iwlwifi/mvm/debugfs.c +++ b/drivers/net/wireless/intel/iwlwifi/mvm/debugfs.c @@ -1529,8 +1529,8 @@ static ssize_t iwl_dbgfs_mem_read(struct file *file, char __user *user_buf, .data = { &cmd, }, .len = { sizeof(cmd) }, }; - size_t delta, len; - ssize_t ret; + size_t delta; + ssize_t ret, len; hcmd.id = iwl_cmd_id(*ppos >> 24 ? UMAC_RD_WR : LMAC_RD_WR, DEBUG_GROUP, 0); -- 2.9.3