[PATCH 5.10 168/599] clocksource: acpi_pm: fix return value of __setup handler

[Greg Kroah-Hartman]

From: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>

[ Upstream commit 6a861abceecb68497dd82a324fee45a5332dcece ]

__setup() handlers should return 1 to obsolete_checksetup() in
init/main.c to indicate that the boot option has been handled.
A return of 0 causes the boot option/value to be listed as an Unknown
kernel parameter and added to init's (limited) environment strings.

The __setup() handler interface isn't meant to handle negative return
values -- they are non-zero, so they mean "handled" (like a return
value of 1 does), but that's just a quirk. So return 1 from
parse_pmtmr(). Also print a warning message if kstrtouint() returns
an error.

Fixes: 6b148507d3d0 ("pmtmr: allow command line override of ioport")
Signed-off-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
Reported-by: Igor Zhbanov <i.zhbanov@xxxxxxxxxxxx>
Link: lore.kernel.org/r/64644a2f-4a20-bab3-1e15-3b2cdd0defe3@xxxxxxxxxxxx
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/clocksource/acpi_pm.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/clocksource/acpi_pm.c b/drivers/clocksource/acpi_pm.c
index eb596ff9e7bb..279ddff81ab4 100644
--- a/drivers/clocksource/acpi_pm.c
+++ b/drivers/clocksource/acpi_pm.c
@@ -229,8 +229,10 @@ static int __init parse_pmtmr(char *arg)
 	int ret;
 
 	ret = kstrtouint(arg, 16, &base);
-	if (ret)
-		return ret;
+	if (ret) {
+		pr_warn("PMTMR: invalid 'pmtmr=' value: '%s'\n", arg);
+		return 1;
+	}
 
 	pr_info("PMTMR IOPort override: 0x%04x -> 0x%04x\n", pmtmr_ioport,
 		base);
-- 
2.34.1