Bug 205303

Summary:	Compilation for PPC64 fails on warning in watchdog.o
Product:	Platform Specific/Hardware	Reporter:	Edward Swiftwood (payphoneed)
Component:	PPC-64	Assignee:	platform_ppc-64
Status:	RESOLVED CODE_FIX
Severity:	blocking	CC:	awilfox, michael
Priority:	P1
Hardware:	PPC-64
OS:	Linux
Kernel Version:	5.3.7	Subsystem:
Regression:	No	Bisected commit-id:

Description Edward Swiftwood 2019-10-24 08:23:39 UTC

Kernel compilation of 5.3.7 on PowerPC 64bit fails with a compiler warning treated as an error.

arch/powerpc/kernel/watchdog.c: In function *watchdog_smp_panic*:
arch/powerpc/kernel/watchdog.c:175:4: error: implicit declaration of function *smp_send_nmi_ipi*: did you mean *smp_send_stop*? [-Werror=implicit-function-declaration]

SMP and Watchdog Timer Support are both disabled in this kernel configuration.

If additional information is necessary please ask.

Comment 1 Edward Swiftwood 2019-10-24 08:33:34 UTC

I failed to mention, the machine is an Apple iMac G5 "PowerMac8,1", PPC970FX @ 1600MHz. (https://everymac.com/systems/apple/imac/specs/imac_g5_1.6_17.html)

Comment 2 A. Wilcox 2019-10-25 08:04:01 UTC

This is because CONFIG_HARDLOCK_DETECTOR is on and CONFIG_NMI_IPI is off.

CONFIG_HARDLOCK_DETECTOR pulls in CONFIG_PPC_WATCHDOG, which unconditionally uses smp_send_nmi_ipi (and I believe requires such to work properly).  CONFIG_PPC_WATCHDOG doesn't depend on CONFIG_NMI_IPI which it probably should.  And then CONFIG_HARDLOCK_DETECTOR_ARCH should probably depend on CONFIG_NMI_IPI or CONFIG_PPC_WATCHDOG.

Comment 3 Michael Ellerman 2021-07-23 10:21:25 UTC

This was fixed by:

4fe529449d85 ("powerpc: Fix HAVE_HARDLOCKUP_DETECTOR_ARCH build configuration")