diff --git a/mm/percpu.c b/mm/percpu.c index 46485e1b26fc..6470e7710231 100644 --- a/mm/percpu.c +++ b/mm/percpu.c @@ -229,8 +229,8 @@ static int __maybe_unused pcpu_page_idx(unsigned int cpu, int page_idx) return pcpu_unit_map[cpu] * pcpu_unit_pages + page_idx; } -static unsigned long __maybe_unused pcpu_chunk_addr(struct pcpu_chunk *chunk, - unsigned int cpu, int page_idx) +static unsigned long pcpu_chunk_addr(struct pcpu_chunk *chunk, + unsigned int cpu, int page_idx) { return (unsigned long)chunk->base_addr + pcpu_unit_offsets[cpu] + (page_idx << PAGE_SHIFT); @@ -978,7 +978,32 @@ bool is_kernel_percpu_address(unsigned long addr) */ phys_addr_t per_cpu_ptr_to_phys(void *addr) { - if (pcpu_addr_in_first_chunk(addr)) { + void __percpu *base = __addr_to_pcpu_ptr(pcpu_base_addr); + bool in_first_chunk = false; + unsigned long first_start, first_end; + unsigned int cpu; + + /* + * The following test on first_start/end isn't strictly + * necessary but will speed up lookups of addresses which + * aren't in the first chunk. + */ + first_start = pcpu_chunk_addr(pcpu_first_chunk, pcpu_first_unit_cpu, 0); + first_end = pcpu_chunk_addr(pcpu_first_chunk, pcpu_last_unit_cpu, + pcpu_unit_pages); + if ((unsigned long)addr >= first_start && + (unsigned long)addr < first_end) { + for_each_possible_cpu(cpu) { + void *start = per_cpu_ptr(base, cpu); + + if (addr >= start && addr < start + pcpu_unit_size) { + in_first_chunk = true; + break; + } + } + } + + if (in_first_chunk) { if ((unsigned long)addr < VMALLOC_START || (unsigned long)addr >= VMALLOC_END) return __pa(addr);