CONFIG_PPC is not available for thedefaultarchitecture x86.
Result is shown for architecture powerpc

CONFIG_PPC (not configurable)

configname: CONFIG_PPC

Linux Kernel Configuration
└─>PPC
In linux kernel since version 2.6.15 (release Date: 2006-01-02)  
selects
CONFIG_ARCH_32BIT_OFF_T
CONFIG_ARCH_DISABLE_KASAN_INLINE
CONFIG_ARCH_ENABLE_MEMORY_HOTPLUG
CONFIG_ARCH_ENABLE_MEMORY_HOTREMOVE
CONFIG_ARCH_HAS_COPY_MC
CONFIG_ARCH_HAS_CURRENT_STACK_POINTER
CONFIG_ARCH_HAS_DEBUG_VIRTUAL
CONFIG_ARCH_HAS_DEBUG_VM_PGTABLE
CONFIG_ARCH_HAS_DEBUG_WX
CONFIG_ARCH_HAS_DEVMEM_IS_ALLOWED
CONFIG_ARCH_HAS_DMA_MAP_DIRECT
CONFIG_ARCH_HAS_FORTIFY_SOURCE
CONFIG_ARCH_HAS_GCOV_PROFILE_ALL
CONFIG_ARCH_HAS_HUGEPD
CONFIG_ARCH_HAS_KCOV
CONFIG_ARCH_HAS_MEMBARRIER_CALLBACKS
CONFIG_ARCH_HAS_MEMBARRIER_SYNC_CORE
CONFIG_ARCH_HAS_MEMREMAP_COMPAT_ALIGN
CONFIG_ARCH_HAS_MMIOWB
CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
CONFIG_ARCH_HAS_PHYS_TO_DMA
CONFIG_ARCH_HAS_PMEM_API
CONFIG_ARCH_HAS_PTE_DEVMAP
CONFIG_ARCH_HAS_PTE_SPECIAL
CONFIG_ARCH_HAS_SCALED_CPUTIME
CONFIG_ARCH_HAS_SET_MEMORY
CONFIG_ARCH_HAS_STRICT_KERNEL_RWX
CONFIG_ARCH_HAS_STRICT_KERNEL_RWX
CONFIG_ARCH_HAS_STRICT_MODULE_RWX
CONFIG_ARCH_HAS_SYSCALL_WRAPPER
CONFIG_ARCH_HAS_TICK_BROADCAST
CONFIG_ARCH_HAS_UACCESS_FLUSHCACHE
CONFIG_ARCH_HAS_UBSAN_SANITIZE_ALL
CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG
CONFIG_ARCH_KEEP_MEMBLOCK
CONFIG_ARCH_MIGHT_HAVE_PC_PARPORT
CONFIG_ARCH_MIGHT_HAVE_PC_SERIO
CONFIG_ARCH_OPTIONAL_KERNEL_RWX
CONFIG_ARCH_OPTIONAL_KERNEL_RWX_DEFAULT
CONFIG_ARCH_SPLIT_ARG64
CONFIG_ARCH_STACKWALK
CONFIG_ARCH_SUPPORTS_ATOMIC_RMW
CONFIG_ARCH_SUPPORTS_DEBUG_PAGEALLOC
CONFIG_ARCH_USE_BUILTIN_BSWAP
CONFIG_ARCH_USE_CMPXCHG_LOCKREF
CONFIG_ARCH_USE_MEMTEST
CONFIG_ARCH_USE_QUEUED_RWLOCKS
CONFIG_ARCH_USE_QUEUED_SPINLOCKS
CONFIG_ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT
CONFIG_ARCH_WANT_IPC_PARSE_VERSION
CONFIG_ARCH_WANT_IRQS_OFF_ACTIVATE_MM
CONFIG_ARCH_WANT_LD_ORPHAN_WARN
CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC
CONFIG_ARCH_WEAK_RELEASE_ACQUIRE
CONFIG_BINFMT_ELF
CONFIG_BUILDTIME_TABLE_SORT
CONFIG_CLONE_BACKWARDS
CONFIG_CPUMASK_OFFSTACK
CONFIG_DCACHE_WORD_ACCESS
CONFIG_DMA_OPS_BYPASS
CONFIG_DMA_OPS
CONFIG_DYNAMIC_FTRACE
CONFIG_EDAC_ATOMIC_SCRUB
CONFIG_EDAC_SUPPORT
CONFIG_GENERIC_ATOMIC64
CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
CONFIG_GENERIC_CMOS_UPDATE
CONFIG_GENERIC_CPU_AUTOPROBE
CONFIG_GENERIC_CPU_VULNERABILITIES
CONFIG_GENERIC_EARLY_IOREMAP
CONFIG_GENERIC_GETTIMEOFDAY
CONFIG_GENERIC_IRQ_SHOW
CONFIG_GENERIC_IRQ_SHOW_LEVEL
CONFIG_GENERIC_PCI_IOMAP
CONFIG_GENERIC_PTDUMP
CONFIG_GENERIC_SMP_IDLE_THREAD
CONFIG_GENERIC_TIME_VSYSCALL
CONFIG_GENERIC_VDSO_TIME_NS
CONFIG_HAVE_ARCH_AUDITSYSCALL
CONFIG_HAVE_ARCH_HUGE_VMALLOC
CONFIG_HAVE_ARCH_HUGE_VMAP
CONFIG_HAVE_ARCH_JUMP_LABEL
CONFIG_HAVE_ARCH_JUMP_LABEL_RELATIVE
CONFIG_HAVE_ARCH_KASAN
CONFIG_HAVE_ARCH_KASAN
CONFIG_HAVE_ARCH_KASAN
CONFIG_HAVE_ARCH_KASAN_VMALLOC
CONFIG_HAVE_ARCH_KFENCE
CONFIG_HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET
CONFIG_HAVE_ARCH_KGDB
CONFIG_HAVE_ARCH_MMAP_RND_BITS
CONFIG_HAVE_ARCH_MMAP_RND_COMPAT_BITS
CONFIG_HAVE_ARCH_NVRAM_OPS
CONFIG_HAVE_ARCH_SECCOMP_FILTER
CONFIG_HAVE_ARCH_TRACEHOOK
CONFIG_HAVE_ASM_MODVERSIONS
CONFIG_HAVE_CONTEXT_TRACKING_USER
CONFIG_HAVE_C_RECORDMCOUNT
CONFIG_HAVE_DEBUG_KMEMLEAK
CONFIG_HAVE_DEBUG_STACKOVERFLOW
CONFIG_HAVE_DYNAMIC_FTRACE
CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS
CONFIG_HAVE_DYNAMIC_FTRACE_WITH_REGS
CONFIG_HAVE_EBPF_JIT
CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
CONFIG_HAVE_FAST_GUP
CONFIG_HAVE_FTRACE_MCOUNT_RECORD
CONFIG_HAVE_FUNCTION_DESCRIPTORS
CONFIG_HAVE_FUNCTION_ERROR_INJECTION
CONFIG_HAVE_FUNCTION_GRAPH_TRACER
CONFIG_HAVE_FUNCTION_TRACER
CONFIG_HAVE_GCC_PLUGINS
CONFIG_HAVE_GENERIC_VDSO
CONFIG_HAVE_HARDLOCKUP_DETECTOR_ARCH
CONFIG_HAVE_HARDLOCKUP_DETECTOR_PERF
CONFIG_HAVE_HW_BREAKPOINT
CONFIG_HAVE_IOREMAP_PROT
CONFIG_HAVE_IRQ_TIME_ACCOUNTING
CONFIG_HAVE_KERNEL_GZIP
CONFIG_HAVE_KERNEL_LZMA
CONFIG_HAVE_KERNEL_LZO
CONFIG_HAVE_KERNEL_XZ
CONFIG_HAVE_KPROBES
CONFIG_HAVE_KPROBES_ON_FTRACE
CONFIG_HAVE_KRETPROBES
CONFIG_HAVE_LD_DEAD_CODE_DATA_ELIMINATION
CONFIG_HAVE_LIVEPATCH
CONFIG_HAVE_MOD_ARCH_SPECIFIC
CONFIG_HAVE_NMI
CONFIG_HAVE_OPTPROBES
CONFIG_HAVE_PERF_EVENTS
CONFIG_HAVE_PERF_EVENTS_NMI
CONFIG_HAVE_PERF_REGS
CONFIG_HAVE_PERF_USER_STACK_DUMP
CONFIG_HAVE_REGS_AND_STACK_ACCESS_API
CONFIG_HAVE_RELIABLE_STACKTRACE
CONFIG_HAVE_RSEQ
CONFIG_HAVE_SETUP_PER_CPU_AREA
CONFIG_HAVE_SOFTIRQ_ON_OWN_STACK
CONFIG_HAVE_STACKPROTECTOR
CONFIG_HAVE_STACKPROTECTOR
CONFIG_HAVE_STATIC_CALL
CONFIG_HAVE_SYSCALL_TRACEPOINTS
CONFIG_HAVE_VIRT_CPU_ACCOUNTING
CONFIG_HUGETLB_PAGE_SIZE_VARIABLE
CONFIG_IOMMU_HELPER
CONFIG_IRQ_DOMAIN
CONFIG_IRQ_FORCED_THREADING
CONFIG_KASAN_VMALLOC
CONFIG_LOCK_MM_AND_FIND_VMA
CONFIG_MMU_GATHER_PAGE_SIZE
CONFIG_MMU_GATHER_RCU_TABLE_FREE
CONFIG_MMU_GATHER_MERGE_VMAS
CONFIG_MODULES_USE_ELF_RELA
CONFIG_NEED_DMA_MAP_STATE
CONFIG_NEED_PER_CPU_EMBED_FIRST_CHUNK
CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK
CONFIG_NEED_SG_DMA_LENGTH
CONFIG_OF
CONFIG_OF_DMA_DEFAULT_COHERENT
CONFIG_OF_EARLY_FLATTREE
CONFIG_OLD_SIGACTION
CONFIG_OLD_SIGSUSPEND
CONFIG_PCI_DOMAINS
CONFIG_PCI_MSI_ARCH_FALLBACKS
CONFIG_PCI_SYSCALL
CONFIG_PPC_DAWR
CONFIG_RTC_LIB
CONFIG_SPARSE_IRQ
CONFIG_STRICT_KERNEL_RWX
CONFIG_SYSCTL_EXCEPTION_TRACE
CONFIG_THREAD_INFO_IN_TASK
CONFIG_TRACE_IRQFLAGS_SUPPORT

is selected by
CONFIG_DEBUG_PAGEALLOC