diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2015-05-19 11:19:49 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2015-05-19 11:19:49 -0700 |
commit | 416716ed390782e373875f39b39ee23c91902688 (patch) | |
tree | aebef7c785d76634dc2b15803f590101ddbf1ceb /arch | |
parent | 68465bb08ca68ab00997ff54a3a27dcb8c541357 (diff) | |
parent | 5e95235ccd5442d4a4fe11ec4eb99ba1b7959368 (diff) |
Merge tag 'powerpc-4.1-4' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux
Pull powerpc fixes from Michael Ellerman:
- THP/hugetlb fixes from Aneesh.
- MCE fix from Daniel.
- TOC fix from Anton.
* tag 'powerpc-4.1-4' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux:
powerpc: Align TOC to 256 bytes
powerpc/mce: fix off by one errors in mce event handling
powerpc/mm: Return NULL for not present hugetlb page
powerpc/thp: Serialize pmd clear against a linux page table walk.
Diffstat (limited to 'arch')
-rw-r--r-- | arch/powerpc/kernel/mce.c | 4 | ||||
-rw-r--r-- | arch/powerpc/kernel/vmlinux.lds.S | 1 | ||||
-rw-r--r-- | arch/powerpc/mm/hugetlbpage.c | 25 | ||||
-rw-r--r-- | arch/powerpc/mm/pgtable_64.c | 11 |
4 files changed, 30 insertions, 11 deletions
diff --git a/arch/powerpc/kernel/mce.c b/arch/powerpc/kernel/mce.c index 15c99b649b04..b2eb4686bd8f 100644 --- a/arch/powerpc/kernel/mce.c +++ b/arch/powerpc/kernel/mce.c @@ -73,7 +73,7 @@ void save_mce_event(struct pt_regs *regs, long handled, uint64_t nip, uint64_t addr) { uint64_t srr1; - int index = __this_cpu_inc_return(mce_nest_count); + int index = __this_cpu_inc_return(mce_nest_count) - 1; struct machine_check_event *mce = this_cpu_ptr(&mce_event[index]); /* @@ -184,7 +184,7 @@ void machine_check_queue_event(void) if (!get_mce_event(&evt, MCE_EVENT_RELEASE)) return; - index = __this_cpu_inc_return(mce_queue_count); + index = __this_cpu_inc_return(mce_queue_count) - 1; /* If queue is full, just return for now. */ if (index >= MAX_MC_EVT) { __this_cpu_dec(mce_queue_count); diff --git a/arch/powerpc/kernel/vmlinux.lds.S b/arch/powerpc/kernel/vmlinux.lds.S index f096e72262f4..1db685104ffc 100644 --- a/arch/powerpc/kernel/vmlinux.lds.S +++ b/arch/powerpc/kernel/vmlinux.lds.S @@ -213,6 +213,7 @@ SECTIONS *(.opd) } + . = ALIGN(256); .got : AT(ADDR(.got) - LOAD_OFFSET) { __toc_start = .; #ifndef CONFIG_RELOCATABLE diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c index 0ce968b00b7c..3385e3d0506e 100644 --- a/arch/powerpc/mm/hugetlbpage.c +++ b/arch/powerpc/mm/hugetlbpage.c @@ -689,27 +689,34 @@ void hugetlb_free_pgd_range(struct mmu_gather *tlb, struct page * follow_huge_addr(struct mm_struct *mm, unsigned long address, int write) { - pte_t *ptep; - struct page *page; + pte_t *ptep, pte; unsigned shift; unsigned long mask, flags; + struct page *page = ERR_PTR(-EINVAL); + + local_irq_save(flags); + ptep = find_linux_pte_or_hugepte(mm->pgd, address, &shift); + if (!ptep) + goto no_page; + pte = READ_ONCE(*ptep); /* + * Verify it is a huge page else bail. * Transparent hugepages are handled by generic code. We can skip them * here. */ - local_irq_save(flags); - ptep = find_linux_pte_or_hugepte(mm->pgd, address, &shift); + if (!shift || pmd_trans_huge(__pmd(pte_val(pte)))) + goto no_page; - /* Verify it is a huge page else bail. */ - if (!ptep || !shift || pmd_trans_huge(*(pmd_t *)ptep)) { - local_irq_restore(flags); - return ERR_PTR(-EINVAL); + if (!pte_present(pte)) { + page = NULL; + goto no_page; } mask = (1UL << shift) - 1; - page = pte_page(*ptep); + page = pte_page(pte); if (page) page += (address & mask) / PAGE_SIZE; +no_page: local_irq_restore(flags); return page; } diff --git a/arch/powerpc/mm/pgtable_64.c b/arch/powerpc/mm/pgtable_64.c index 59daa5eeec25..6bfadf1aa5cb 100644 --- a/arch/powerpc/mm/pgtable_64.c +++ b/arch/powerpc/mm/pgtable_64.c @@ -839,6 +839,17 @@ pmd_t pmdp_get_and_clear(struct mm_struct *mm, * hash fault look at them. */ memset(pgtable, 0, PTE_FRAG_SIZE); + /* + * Serialize against find_linux_pte_or_hugepte which does lock-less + * lookup in page tables with local interrupts disabled. For huge pages + * it casts pmd_t to pte_t. Since format of pte_t is different from + * pmd_t we want to prevent transit from pmd pointing to page table + * to pmd pointing to huge page (and back) while interrupts are disabled. + * We clear pmd to possibly replace it with page table pointer in + * different code paths. So make sure we wait for the parallel + * find_linux_pte_or_hugepage to finish. + */ + kick_all_cpus_sync(); return old_pmd; } |