Hi Russell, One inline comment. > -----Original Message----- > From: Russell King <rmk@xxxxxxxxxxxxxxx> On Behalf Of Russell King > Sent: 2023年10月24日 23:19 > To: linux-pm@xxxxxxxxxxxxxxx; loongarch@xxxxxxxxxxxxxxx; > linux-acpi@xxxxxxxxxxxxxxx; linux-arch@xxxxxxxxxxxxxxx; > linux-kernel@xxxxxxxxxxxxxxx; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; > linux-riscv@xxxxxxxxxxxxxxxxxxx; kvmarm@xxxxxxxxxxxxxxx; x86@xxxxxxxxxx; > linux-csky@xxxxxxxxxxxxxxx; linux-doc@xxxxxxxxxxxxxxx; > linux-ia64@xxxxxxxxxxxxxxx; linux-parisc@xxxxxxxxxxxxxxx > Cc: Salil Mehta <salil.mehta@xxxxxxxxxx>; Jean-Philippe Brucker > <jean-philippe@xxxxxxxxxx>; Jianyong Wu <Jianyong.Wu@xxxxxxx>; Justin He > <Justin.He@xxxxxxx>; James Morse <James.Morse@xxxxxxx>; Catalin > Marinas <Catalin.Marinas@xxxxxxx>; Will Deacon <will@xxxxxxxxxx>; Mark > Rutland <Mark.Rutland@xxxxxxx>; Lorenzo Pieralisi <lpieralisi@xxxxxxxxxx> > Subject: [PATCH 34/39] arm64: psci: Ignore DENIED CPUs > > From: Jean-Philippe Brucker <jean-philippe@xxxxxxxxxx> > > When a CPU is marked as disabled, but online capable in the MADT, PSCI applies > some firmware policy to control when it can be brought online. > PSCI returns DENIED to a CPU_ON request if this is not currently permitted. The > OS can learn the current policy from the _STA enabled bit. > > Handle the PSCI DENIED return code gracefully instead of printing an error. > > See https://developer.arm.com/documentation/den0022/f/?lang=en page 58. > > Signed-off-by: Jean-Philippe Brucker <jean-philippe@xxxxxxxxxx> [ morse: > Rewrote commit message ] > Signed-off-by: James Morse <james.morse@xxxxxxx> > Signed-off-by: Russell King (Oracle) <rmk+kernel@xxxxxxxxxxxxxxx> > --- > Changes since RFC v2 > * Add specification reference > * Use EPERM rather than EPROBE_DEFER > --- > arch/arm64/kernel/psci.c | 2 +- > arch/arm64/kernel/smp.c | 3 ++- > drivers/firmware/psci/psci.c | 2 ++ > 3 files changed, 5 insertions(+), 2 deletions(-) > > diff --git a/arch/arm64/kernel/psci.c b/arch/arm64/kernel/psci.c index > 29a8e444db83..4fcc0cdd757b 100644 > --- a/arch/arm64/kernel/psci.c > +++ b/arch/arm64/kernel/psci.c > @@ -40,7 +40,7 @@ static int cpu_psci_cpu_boot(unsigned int cpu) { > phys_addr_t pa_secondary_entry = __pa_symbol(secondary_entry); > int err = psci_ops.cpu_on(cpu_logical_map(cpu), pa_secondary_entry); > - if (err) > + if (err && err != -EPROBE_DEFER) Should this be EPERM? As the following psci cpu_on op will return it. I think you miss to change this when apply Jean-Philippe's patch. Thanks Jianyong > pr_err("failed to boot CPU%d (%d)\n", cpu, err); > > return err; > diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c index > 8c8f55721786..68ec7fbe166f 100644 > --- a/arch/arm64/kernel/smp.c > +++ b/arch/arm64/kernel/smp.c > @@ -124,7 +124,8 @@ int __cpu_up(unsigned int cpu, struct task_struct *idle) > /* Now bring the CPU into our world */ > ret = boot_secondary(cpu, idle); > if (ret) { > - pr_err("CPU%u: failed to boot: %d\n", cpu, ret); > + if (ret != -EPERM) > + pr_err("CPU%u: failed to boot: %d\n", cpu, ret); > return ret; > } > > diff --git a/drivers/firmware/psci/psci.c b/drivers/firmware/psci/psci.c index > d9629ff87861..ee82e7880d8c 100644 > --- a/drivers/firmware/psci/psci.c > +++ b/drivers/firmware/psci/psci.c > @@ -218,6 +218,8 @@ static int __psci_cpu_on(u32 fn, unsigned long cpuid, > unsigned long entry_point) > int err; > > err = invoke_psci_fn(fn, cpuid, entry_point, 0); > + if (err == PSCI_RET_DENIED) > + return -EPERM; > return psci_to_linux_errno(err); > } > > -- > 2.30.2
