Hi Gavin, On Sun, Jun 30, 2024 at 10:39:04AM +1000, Gavin Shan wrote: > On 5/29/24 11:34 PM, Jonathan Cameron wrote: > > In order to move arch_register_cpu() to be called via the same path > > for initially present CPUs described by ACPI and hotplugged CPUs > > ACPI_HOTPLUG_CPU needs to be enabled. > > > > The protection against invalid IDs in acpi_map_cpu() is needed as > > at least one production BIOS is in the wild which reports entries > > in DSDT (with no _STA method, so assumed enabled and present) > > that don't match MADT. > > > > Tested-by: Miguel Luis <miguel.luis@xxxxxxxxxx> > > Reviewed-by: Gavin Shan <gshan@xxxxxxxxxx> > > Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx> > > --- > > arch/arm64/Kconfig | 1 + > > arch/arm64/kernel/acpi.c | 22 ++++++++++++++++++++++ > > 2 files changed, 23 insertions(+) > > > > diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig > > index 5d91259ee7b5..e8f2ef2312db 100644 > > --- a/arch/arm64/Kconfig > > +++ b/arch/arm64/Kconfig > > @@ -5,6 +5,7 @@ config ARM64 > > select ACPI_CCA_REQUIRED if ACPI > > select ACPI_GENERIC_GSI if ACPI > > select ACPI_GTDT if ACPI > > + select ACPI_HOTPLUG_CPU if ACPI_PROCESSOR > > ACPI_HOTPLUG_CPU depends on (ACPI_PROCESSOR && HOTPLUG_CPU). It needs to be: > > select ACPI_HOTPLUG_CPU if ACPI_PROCESSOR && HOTPLUG_CPU > > Otherwise, we can have compiling error with the following configurations. > > CONFIG_ACPI_PROCESSOR=y > CONFIG_HOTPLUG_CPU=n > CONFIG_ACPI_HOTPLUG_CPU=y > > arch/arm64/kernel/smp.c: In function ‘arch_unregister_cpu’: > arch/arm64/kernel/smp.c:563:9: error: implicit declaration of function ‘unregister_cpu’; did you mean ‘register_cpu’? [-Werror=implicit-function-declaration] > 563 | unregister_cpu(c); > | ^~~~~~~~~~~~~~ > | register_cpu Ah, I thought that in addition to the warning for unmet dependencies, kbuild would also leave the option off. I need to add SUSPEND=n and HIBERNATE=n to my build scripts. The fix matches what x86 does, so I'm ok with it. > Since the series has been queued to Catalin's "for-next/vcpu-hotplug" branch, I > guess the easiest way would be to fix it in place with Catalin's help. I wasn't planning to rebase the branch unless there's something major. Since the doesn't happen with defconfig, it's doesn't affect bisection that much, so my preference would be for a fix on top of this branch (and with a Fixes: tag since the branch is stable). Thanks. -- Catalin
