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| author | Ingo Molnar <mingo@kernel.org> | 2018-12-03 13:42:17 +0300 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2018-12-03 13:42:17 +0300 |
| commit | 5f675231e456cb599b283f8361f01cf34b0617df (patch) | |
| tree | afb2bdfd6fdbb18336146f41ba7659120a5ff9d2 /mm/hugetlb.c | |
| parent | 3e184501083c38fa091f640acb13af17a21fd228 (diff) | |
| parent | 2595646791c319cadfdbf271563aac97d0843dc7 (diff) | |
| download | linux-5f675231e456cb599b283f8361f01cf34b0617df.tar.xz | |
Merge tag 'v4.20-rc5' into sched/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'mm/hugetlb.c')
| -rw-r--r-- | mm/hugetlb.c | 31 |
1 files changed, 23 insertions, 8 deletions
diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 7b5c0ad9a6bd..705a3e9cc910 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -15,7 +15,7 @@ #include <linux/compiler.h> #include <linux/cpuset.h> #include <linux/mutex.h> -#include <linux/bootmem.h> +#include <linux/memblock.h> #include <linux/sysfs.h> #include <linux/slab.h> #include <linux/mmdebug.h> @@ -2100,9 +2100,9 @@ int __alloc_bootmem_huge_page(struct hstate *h) for_each_node_mask_to_alloc(h, nr_nodes, node, &node_states[N_MEMORY]) { void *addr; - addr = memblock_virt_alloc_try_nid_raw( + addr = memblock_alloc_try_nid_raw( huge_page_size(h), huge_page_size(h), - 0, BOOTMEM_ALLOC_ACCESSIBLE, node); + 0, MEMBLOCK_ALLOC_ACCESSIBLE, node); if (addr) { /* * Use the beginning of the huge page to store the @@ -3233,7 +3233,7 @@ static int is_hugetlb_entry_hwpoisoned(pte_t pte) int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src, struct vm_area_struct *vma) { - pte_t *src_pte, *dst_pte, entry; + pte_t *src_pte, *dst_pte, entry, dst_entry; struct page *ptepage; unsigned long addr; int cow; @@ -3261,15 +3261,30 @@ int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src, break; } - /* If the pagetables are shared don't copy or take references */ - if (dst_pte == src_pte) + /* + * If the pagetables are shared don't copy or take references. + * dst_pte == src_pte is the common case of src/dest sharing. + * + * However, src could have 'unshared' and dst shares with + * another vma. If dst_pte !none, this implies sharing. + * Check here before taking page table lock, and once again + * after taking the lock below. + */ + dst_entry = huge_ptep_get(dst_pte); + if ((dst_pte == src_pte) || !huge_pte_none(dst_entry)) continue; dst_ptl = huge_pte_lock(h, dst, dst_pte); src_ptl = huge_pte_lockptr(h, src, src_pte); spin_lock_nested(src_ptl, SINGLE_DEPTH_NESTING); entry = huge_ptep_get(src_pte); - if (huge_pte_none(entry)) { /* skip none entry */ + dst_entry = huge_ptep_get(dst_pte); + if (huge_pte_none(entry) || !huge_pte_none(dst_entry)) { + /* + * Skip if src entry none. Also, skip in the + * unlikely case dst entry !none as this implies + * sharing with another vma. + */ ; } else if (unlikely(is_hugetlb_entry_migration(entry) || is_hugetlb_entry_hwpoisoned(entry))) { @@ -4065,7 +4080,7 @@ int hugetlb_mcopy_atomic_pte(struct mm_struct *dst_mm, /* fallback to copy_from_user outside mmap_sem */ if (unlikely(ret)) { - ret = -EFAULT; + ret = -ENOENT; *pagep = page; /* don't free the page */ goto out; |