From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "Maciej W. Rozycki" , Alexandre Belloni Subject: [PATCH 4.19 286/361] rtc: cmos: Fix non-ACPI undefined reference to `hpet_rtc_interrupt Date: Sun, 11 Nov 2018 14:20:33 -0800 Message-Id: <20181111221656.308454300@linuxfoundation.org> In-Reply-To: <20181111221619.915519183@linuxfoundation.org> References: <20181111221619.915519183@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: 4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Maciej W. Rozycki commit d197a253855d2d8e507a003880aab35c4e2473db upstream. Fix a commit 311ee9c151ad ("rtc: cmos: allow using ACPI for RTC alarm instead of HPET") `rtc-cmos' regression causing a link error: drivers/rtc/rtc-cmos.o: In function `cmos_platform_probe': rtc-cmos.c:(.init.text+0x33c): undefined reference to `hpet_rtc_interrupt' rtc-cmos.c:(.init.text+0x3f4): undefined reference to `hpet_rtc_interrupt' with non-ACPI platforms using this driver. The cause is the change of the condition guarding the use of `hpet_rtc_interrupt'. Previously it was a call to `is_hpet_enabled'. That function is static inline and has a hardcoded 0 result for non-ACPI platforms, which imply !HPET_EMULATE_RTC. Consequently the compiler optimized the whole block away including the reference to `hpet_rtc_interrupt', which never made it to the link stage. Now the guarding condition is a call to `use_hpet_alarm', which is not static inline and therefore the compiler may not be able to prove that it actually always returns 0 for non-ACPI platforms. Consequently the build breaks with an unsatisfied reference, because `hpet_rtc_interrupt' is nowhere defined at link time. Fix the problem by marking `use_hpet_alarm' inline. As the `inline' keyword serves as an optimization hint rather than a requirement the compiler is still free to choose whether inlining will be beneficial or not for ACPI platforms. Signed-off-by: Maciej W. Rozycki Fixes: 311ee9c151ad ("rtc: cmos: allow using ACPI for RTC alarm instead of HPET") Cc: stable@vger.kernel.org # 4.18+ Signed-off-by: Alexandre Belloni Signed-off-by: Greg Kroah-Hartman --- drivers/rtc/rtc-cmos.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/rtc/rtc-cmos.c +++ b/drivers/rtc/rtc-cmos.c @@ -167,7 +167,7 @@ static inline int hpet_unregister_irq_ha #endif /* Don't use HPET for RTC Alarm event if ACPI Fixed event is used */ -static int use_hpet_alarm(void) +static inline int use_hpet_alarm(void) { return is_hpet_enabled() && !use_acpi_alarm; }