diff options
| -rw-r--r-- | arch/powerpc/include/asm/lppaca.h | 24 | ||||
| -rw-r--r-- | arch/powerpc/kernel/machine_kexec_64.c | 15 | ||||
| -rw-r--r-- | arch/powerpc/kernel/paca.c | 89 | ||||
| -rw-r--r-- | arch/powerpc/kvm/book3s_hv.c | 3 | ||||
| -rw-r--r-- | arch/powerpc/mm/numa.c | 4 | ||||
| -rw-r--r-- | arch/powerpc/platforms/pseries/kexec.c | 7 |
6 files changed, 63 insertions, 79 deletions
diff --git a/arch/powerpc/include/asm/lppaca.h b/arch/powerpc/include/asm/lppaca.h index 6e4589eee2da..65d589689f01 100644 --- a/arch/powerpc/include/asm/lppaca.h +++ b/arch/powerpc/include/asm/lppaca.h @@ -36,14 +36,16 @@ #include <asm/mmu.h> /* - * We only have to have statically allocated lppaca structs on - * legacy iSeries, which supports at most 64 cpus. - */ -#define NR_LPPACAS 1 - -/* - * The Hypervisor barfs if the lppaca crosses a page boundary. A 1k - * alignment is sufficient to prevent this + * The lppaca is the "virtual processor area" registered with the hypervisor, + * H_REGISTER_VPA etc. + * + * According to PAPR, the structure is 640 bytes long, must be L1 cache line + * aligned, and must not cross a 4kB boundary. Its size field must be at + * least 640 bytes (but may be more). + * + * Pre-v4.14 KVM hypervisors reject the VPA if its size field is smaller than + * 1kB, so we dynamically allocate 1kB and advertise size as 1kB, but keep + * this structure as the canonical 640 byte size. */ struct lppaca { /* cacheline 1 contains read-only data */ @@ -97,11 +99,9 @@ struct lppaca { __be32 page_ins; /* CMO Hint - # page ins by OS */ u8 reserved11[148]; - volatile __be64 dtl_idx; /* Dispatch Trace Log head index */ + volatile __be64 dtl_idx; /* Dispatch Trace Log head index */ u8 reserved12[96]; -} __attribute__((__aligned__(0x400))); - -extern struct lppaca lppaca[]; +} ____cacheline_aligned; #define lppaca_of(cpu) (*paca_ptrs[cpu]->lppaca_ptr) diff --git a/arch/powerpc/kernel/machine_kexec_64.c b/arch/powerpc/kernel/machine_kexec_64.c index a250e3331f94..1044bf15d5ed 100644 --- a/arch/powerpc/kernel/machine_kexec_64.c +++ b/arch/powerpc/kernel/machine_kexec_64.c @@ -323,17 +323,24 @@ void default_machine_kexec(struct kimage *image) kexec_stack.thread_info.cpu = current_thread_info()->cpu; /* We need a static PACA, too; copy this CPU's PACA over and switch to - * it. Also poison per_cpu_offset to catch anyone using non-static - * data. + * it. Also poison per_cpu_offset and NULL lppaca to catch anyone using + * non-static data. */ memcpy(&kexec_paca, get_paca(), sizeof(struct paca_struct)); kexec_paca.data_offset = 0xedeaddeadeeeeeeeUL; +#ifdef CONFIG_PPC_PSERIES + kexec_paca.lppaca_ptr = NULL; +#endif paca_ptrs[kexec_paca.paca_index] = &kexec_paca; + setup_paca(&kexec_paca); - /* XXX: If anyone does 'dynamic lppacas' this will also need to be - * switched to a static version! + /* + * The lppaca should be unregistered at this point so the HV won't + * touch it. In the case of a crash, none of the lppacas are + * unregistered so there is not much we can do about it here. */ + /* * On Book3S, the copy must happen with the MMU off if we are either * using Radix page tables or we are not in an LPAR since we can diff --git a/arch/powerpc/kernel/paca.c b/arch/powerpc/kernel/paca.c index eef4891c9af6..6cddb9bdc151 100644 --- a/arch/powerpc/kernel/paca.c +++ b/arch/powerpc/kernel/paca.c @@ -23,82 +23,50 @@ #ifdef CONFIG_PPC_PSERIES /* - * The structure which the hypervisor knows about - this structure - * should not cross a page boundary. The vpa_init/register_vpa call - * is now known to fail if the lppaca structure crosses a page - * boundary. The lppaca is also used on POWER5 pSeries boxes. - * The lppaca is 640 bytes long, and cannot readily - * change since the hypervisor knows its layout, so a 1kB alignment - * will suffice to ensure that it doesn't cross a page boundary. + * See asm/lppaca.h for more detail. + * + * lppaca structures must must be 1kB in size, L1 cache line aligned, + * and not cross 4kB boundary. A 1kB size and 1kB alignment will satisfy + * these requirements. */ -struct lppaca lppaca[] = { - [0 ... (NR_LPPACAS-1)] = { +static inline void init_lppaca(struct lppaca *lppaca) +{ + BUILD_BUG_ON(sizeof(struct lppaca) != 640); + + *lppaca = (struct lppaca) { .desc = cpu_to_be32(0xd397d781), /* "LpPa" */ - .size = cpu_to_be16(sizeof(struct lppaca)), + .size = cpu_to_be16(0x400), .fpregs_in_use = 1, .slb_count = cpu_to_be16(64), .vmxregs_in_use = 0, - .page_ins = 0, - }, + .page_ins = 0, }; }; -static struct lppaca *extra_lppacas; -static long __initdata lppaca_size; - -static void __init allocate_lppacas(int nr_cpus, unsigned long limit) -{ - if (early_cpu_has_feature(CPU_FTR_HVMODE)) - return; - - if (nr_cpus <= NR_LPPACAS) - return; - - lppaca_size = PAGE_ALIGN(sizeof(struct lppaca) * - (nr_cpus - NR_LPPACAS)); - extra_lppacas = __va(memblock_alloc_base(lppaca_size, - PAGE_SIZE, limit)); -} - -static struct lppaca * __init new_lppaca(int cpu) +static struct lppaca * __init new_lppaca(int cpu, unsigned long limit) { struct lppaca *lp; + size_t size = 0x400; + + BUILD_BUG_ON(size < sizeof(struct lppaca)); if (early_cpu_has_feature(CPU_FTR_HVMODE)) return NULL; - if (cpu < NR_LPPACAS) - return &lppaca[cpu]; - - lp = extra_lppacas + (cpu - NR_LPPACAS); - *lp = lppaca[0]; + lp = __va(memblock_alloc_base(size, 0x400, limit)); + init_lppaca(lp); return lp; } -static void __init free_lppacas(void) +static void __init free_lppaca(struct lppaca *lp) { - long new_size = 0, nr; + size_t size = 0x400; if (early_cpu_has_feature(CPU_FTR_HVMODE)) return; - if (!lppaca_size) - return; - nr = num_possible_cpus() - NR_LPPACAS; - if (nr > 0) - new_size = PAGE_ALIGN(nr * sizeof(struct lppaca)); - if (new_size >= lppaca_size) - return; - - memblock_free(__pa(extra_lppacas) + new_size, lppaca_size - new_size); - lppaca_size = new_size; + memblock_free(__pa(lp), size); } - -#else - -static inline void allocate_lppacas(int nr_cpus, unsigned long limit) { } -static inline void free_lppacas(void) { } - #endif /* CONFIG_PPC_BOOK3S */ #ifdef CONFIG_PPC_BOOK3S_64 @@ -167,7 +135,7 @@ EXPORT_SYMBOL(paca_ptrs); void __init initialise_paca(struct paca_struct *new_paca, int cpu) { #ifdef CONFIG_PPC_PSERIES - new_paca->lppaca_ptr = new_lppaca(cpu); + new_paca->lppaca_ptr = NULL; #endif #ifdef CONFIG_PPC_BOOK3E new_paca->kernel_pgd = swapper_pg_dir; @@ -254,13 +222,15 @@ void __init allocate_pacas(void) printk(KERN_DEBUG "Allocated %lu bytes for %u pacas\n", size, nr_cpu_ids); - allocate_lppacas(nr_cpu_ids, limit); - allocate_slb_shadows(nr_cpu_ids, limit); /* Can't use for_each_*_cpu, as they aren't functional yet */ - for (cpu = 0; cpu < nr_cpu_ids; cpu++) + for (cpu = 0; cpu < nr_cpu_ids; cpu++) { initialise_paca(paca_ptrs[cpu], cpu); +#ifdef CONFIG_PPC_PSERIES + paca_ptrs[cpu]->lppaca_ptr = new_lppaca(cpu, limit); +#endif + } } void __init free_unused_pacas(void) @@ -272,6 +242,9 @@ void __init free_unused_pacas(void) for (cpu = 0; cpu < paca_nr_cpu_ids; cpu++) { if (!cpu_possible(cpu)) { unsigned long pa = __pa(paca_ptrs[cpu]); +#ifdef CONFIG_PPC_PSERIES + free_lppaca(paca_ptrs[cpu]->lppaca_ptr); +#endif memblock_free(pa, sizeof(struct paca_struct)); paca_ptrs[cpu] = NULL; size += sizeof(struct paca_struct); @@ -288,8 +261,6 @@ void __init free_unused_pacas(void) if (size) printk(KERN_DEBUG "Freed %lu bytes for unused pacas\n", size); - free_lppacas(); - paca_nr_cpu_ids = nr_cpu_ids; paca_ptrs_size = new_ptrs_size; } diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c index 41fce69714d5..9b48d4a191ff 100644 --- a/arch/powerpc/kvm/book3s_hv.c +++ b/arch/powerpc/kvm/book3s_hv.c @@ -498,7 +498,8 @@ static unsigned long do_h_register_vpa(struct kvm_vcpu *vcpu, * use 640 bytes of the structure though, so we should accept * clients that set a size of 640. */ - if (len < 640) + BUILD_BUG_ON(sizeof(struct lppaca) != 640); + if (len < sizeof(struct lppaca)) break; vpap = &tvcpu->arch.vpa; err = 0; diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c index 314d19ab9385..e9ec465068f1 100644 --- a/arch/powerpc/mm/numa.c +++ b/arch/powerpc/mm/numa.c @@ -1110,7 +1110,7 @@ static void setup_cpu_associativity_change_counters(void) for_each_possible_cpu(cpu) { int i; u8 *counts = vphn_cpu_change_counts[cpu]; - volatile u8 *hypervisor_counts = lppaca[cpu].vphn_assoc_counts; + volatile u8 *hypervisor_counts = lppaca_of(cpu).vphn_assoc_counts; for (i = 0; i < distance_ref_points_depth; i++) counts[i] = hypervisor_counts[i]; @@ -1136,7 +1136,7 @@ static int update_cpu_associativity_changes_mask(void) for_each_possible_cpu(cpu) { int i, changed = 0; u8 *counts = vphn_cpu_change_counts[cpu]; - volatile u8 *hypervisor_counts = lppaca[cpu].vphn_assoc_counts; + volatile u8 *hypervisor_counts = lppaca_of(cpu).vphn_assoc_counts; for (i = 0; i < distance_ref_points_depth; i++) { if (hypervisor_counts[i] != counts[i]) { diff --git a/arch/powerpc/platforms/pseries/kexec.c b/arch/powerpc/platforms/pseries/kexec.c index eeb13429d685..3fe126796975 100644 --- a/arch/powerpc/platforms/pseries/kexec.c +++ b/arch/powerpc/platforms/pseries/kexec.c @@ -23,7 +23,12 @@ void pseries_kexec_cpu_down(int crash_shutdown, int secondary) { - /* Don't risk a hypervisor call if we're crashing */ + /* + * Don't risk a hypervisor call if we're crashing + * XXX: Why? The hypervisor is not crashing. It might be better + * to at least attempt unregister to avoid the hypervisor stepping + * on our memory. + */ if (firmware_has_feature(FW_FEATURE_SPLPAR) && !crash_shutdown) { int ret; int cpu = smp_processor_id(); |