diff options
Diffstat (limited to 'mm/memory.c')
| -rw-r--r-- | mm/memory.c | 23 |
1 files changed, 20 insertions, 3 deletions
diff --git a/mm/memory.c b/mm/memory.c index 793fe0f9841c..fc1987dfd8cc 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -1649,10 +1649,14 @@ EXPORT_SYMBOL(vm_insert_pfn_prot); int vm_insert_mixed(struct vm_area_struct *vma, unsigned long addr, pfn_t pfn) { + pgprot_t pgprot = vma->vm_page_prot; + BUG_ON(!(vma->vm_flags & VM_MIXEDMAP)); if (addr < vma->vm_start || addr >= vma->vm_end) return -EFAULT; + if (track_pfn_insert(vma, &pgprot, pfn)) + return -EINVAL; /* * If we don't have pte special, then we have to use the pfn_valid() @@ -1670,9 +1674,9 @@ int vm_insert_mixed(struct vm_area_struct *vma, unsigned long addr, * result in pfn_t_has_page() == false. */ page = pfn_to_page(pfn_t_to_pfn(pfn)); - return insert_page(vma, addr, page, vma->vm_page_prot); + return insert_page(vma, addr, page, pgprot); } - return insert_pfn(vma, addr, pfn, vma->vm_page_prot); + return insert_pfn(vma, addr, pfn, pgprot); } EXPORT_SYMBOL(vm_insert_mixed); @@ -3395,7 +3399,7 @@ static int do_numa_page(struct fault_env *fe, pte_t pte) * pte_dirty has unpredictable behaviour between PTE scan updates, * background writeback, dirty balancing and application behaviour. */ - if (!(vma->vm_flags & VM_WRITE)) + if (!pte_write(pte)) flags |= TNF_NO_GROUP; /* @@ -3658,6 +3662,19 @@ int handle_mm_fault(struct vm_area_struct *vma, unsigned long address, mem_cgroup_oom_synchronize(false); } + /* + * This mm has been already reaped by the oom reaper and so the + * refault cannot be trusted in general. Anonymous refaults would + * lose data and give a zero page instead e.g. This is especially + * problem for use_mm() because regular tasks will just die and + * the corrupted data will not be visible anywhere while kthread + * will outlive the oom victim and potentially propagate the date + * further. + */ + if (unlikely((current->flags & PF_KTHREAD) && !(ret & VM_FAULT_ERROR) + && test_bit(MMF_UNSTABLE, &vma->vm_mm->flags))) + ret = VM_FAULT_SIGBUS; + return ret; } EXPORT_SYMBOL_GPL(handle_mm_fault); |