Changed HOTPLUG_CPU dependency to SMP and either ARCH_HIBERNATION_POSSIBLE or ARCH_SUSPEND_POSSIBLE, aligning with systems' suspend/hibernation capabilities. This update links CPU hotplugging more logically with platforms' capabilities.
Other changes include 1. configs ARCH_HIBERNATION_POSSIBLE and ARCH_SUSPEND_POSSIBLE are now selected only if required platform dependencies are met. 2. Defaults for configs ARCH_HIBERNATION_POSSIBLE and ARCH_SUSPEND_POSSIBLE has been set to 'N' Reported-by: Srikar Dronamraju <sri...@linux.vnet.ibm.com> Suggested-by: Aneesh Kumar K V <aneesh.ku...@linux.ibm.com> Suggested-by: Michael Ellerman <m...@ellerman.id.au> Signed-off-by: Vishal Chourasia <vish...@linux.ibm.com> v1: https://lore.kernel.org/all/20231114082046.6018-1-vish...@linux.ibm.com --- During the configuration process with 'make randconfig' followed by 'make olddefconfig', we observed a warning indicating an unmet direct dependency for the HOTPLUG_CPU option. The dependency in question relates to various PowerPC configurations (PPC_PSERIES, PPC_PMAC, PPC_POWERNV, FSL_SOC_BOOKE) which were not enabled, yet the HOTPLUG_CPU was being erroneously selected due to an implicit assumption by the PM_SLEEP_SMP option. This misalignment in dependencies could potentially lead to inconsistent kernel configuration states, especially when considering the necessary hardware support for CPU hot-plugging on PowerPC platforms. The patch aims to correct this by ensuring that ARCH_HIBERNATION_POSSIBLE is contingent upon the appropriate PowerPC configurations being active. steps to reproduce (before applying the patch): Run 'make pseries_le_defconfig' Run 'make menuconfig' Enable hibernation [ Kernel options -> Hibernation (aka 'suspend to disk') ] Disable [ Platform support -> IBM PowerNV (Non-Virtualized) platform support ] Disable [ Platform support -> IBM pSeries & new (POWER5-based) iSeries ] Enable SMP [ Processor support -> Symmetric multi-processing support ] Save the config Run 'make olddefconfig' arch/powerpc/Kconfig | 13 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-) diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 6f105ee4f3cf..6e7e9af2f0c1 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -155,6 +155,8 @@ config PPC select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST select ARCH_HAS_UACCESS_FLUSHCACHE select ARCH_HAS_UBSAN_SANITIZE_ALL + select ARCH_HIBERNATION_POSSIBLE if (PPC_PSERIES || PPC_PMAC || PPC_POWERNV || FSL_SOC_BOOKE) + select ARCH_SUSPEND_POSSIBLE if (ADB_PMU || PPC_EFIKA || PPC_LITE5200 || PPC_83xx || (PPC_85xx && !PPC_E500MC) || PPC_86xx || PPC_PSERIES || 44x || 40x) select ARCH_HAVE_NMI_SAFE_CMPXCHG select ARCH_KEEP_MEMBLOCK select ARCH_MHP_MEMMAP_ON_MEMORY_ENABLE if PPC_RADIX_MMU @@ -380,14 +382,10 @@ config DEFAULT_UIMAGE Used to allow a board to specify it wants a uImage built by default config ARCH_HIBERNATION_POSSIBLE - bool - default y + def_bool n config ARCH_SUSPEND_POSSIBLE - def_bool y - depends on ADB_PMU || PPC_EFIKA || PPC_LITE5200 || PPC_83xx || \ - (PPC_85xx && !PPC_E500MC) || PPC_86xx || PPC_PSERIES \ - || 44x || 40x + def_bool n config ARCH_SUSPEND_NONZERO_CPU def_bool y @@ -568,8 +566,7 @@ config ARCH_USING_PATCHABLE_FUNCTION_ENTRY config HOTPLUG_CPU bool "Support for enabling/disabling CPUs" - depends on SMP && (PPC_PSERIES || \ - PPC_PMAC || PPC_POWERNV || FSL_SOC_BOOKE) + depends on SMP && (ARCH_HIBERNATION_POSSIBLE || ARCH_SUSPEND_POSSIBLE) help Say Y here to be able to disable and re-enable individual CPUs at runtime on SMP machines. -- 2.41.0