linux-kernel - [PATCH] opp: avoid uninitialized-variable use

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Date:   Fri, 29 May 2020 22:17:16 +0200
From:   Arnd Bergmann <arnd@...db.de>
To:     Viresh Kumar <vireshk@...nel.org>, Nishanth Menon <nm@...com>,
        Stephen Boyd <sboyd@...nel.org>,
        Georgi Djakov <georgi.djakov@...aro.org>
Cc:     Arnd Bergmann <arnd@...db.de>, Sibi Sankar <sibis@...eaurora.org>,
        Viresh Kumar <viresh.kumar@...aro.org>,
        Matthias Kaehlcke <mka@...omium.org>,
        Rajendra Nayak <rnayak@...eaurora.org>,
        linux-pm@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: [PATCH] opp: avoid uninitialized-variable use

An uninitialized pointer is passed into another function but
ignored there:

drivers/opp/core.c:875:32: error: variable 'opp' is uninitialized when used here [-Werror,-Wuninitialized]
                ret = _set_opp_bw(opp_table, opp, dev, true);
                                             ^~~
drivers/opp/core.c:849:34: note: initialize the variable 'opp' to silence this warning
        struct dev_pm_opp *old_opp, *opp;
                                        ^

gcc no longer warns about this, but it seems it really should,
so change the code to just pass a NULL pointer here.

See-also: 78a5255ffb6a ("Stop the ad-hoc games with -Wno-maybe-initialized")
Fixes: c57afacc9270 ("opp: Remove bandwidth votes when target_freq is zero")
Signed-off-by: Arnd Bergmann <arnd@...db.de>
---
 drivers/opp/core.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/opp/core.c b/drivers/opp/core.c
index df12c3804533..7302f2631f8d 100644
--- a/drivers/opp/core.c
+++ b/drivers/opp/core.c
@@ -872,7 +872,7 @@ int dev_pm_opp_set_rate(struct device *dev, unsigned long target_freq)
 			goto put_opp_table;
 		}
 
-		ret = _set_opp_bw(opp_table, opp, dev, true);
+		ret = _set_opp_bw(opp_table, NULL, dev, true);
 		if (ret)
 			return ret;
 
-- 
2.26.2