On Wed, Oct 04, 2017 at 06:03:47AM +0000, Vlastimil Babka wrote:
> On 10/02/2017 10:04 AM, Kirill A. Shutemov wrote:
> > On machine with 5-level paging support a process can allocate
> > significant amount of memory and stay unnoticed by oom-killer and
> > memory cgroup. The trick is to allocate a lot of PUD page tables.
> > We don't account PUD page tables, only PMD and PTE.
> >
> > We already addressed the same issue for PMD page tables, see
> > dc6c9a35b66b ("mm: account pmd page tables to the process").
> > Introduction 5-level paging bring the same issue for PUD page tables.
> >
> > The patch expands accounting to PUD level.
> >
> > Signed-off-by: Kirill A. Shutemov <kirill.shute...@linux.intel.com>
> > Cc: Michal Hocko <mho...@suse.com>
> > Cc: Vlastimil Babka <vba...@suse.cz>
>
> Acked-by: Vlastimil Babka <vba...@suse.cz>
>
> Small fix below:
>
> > --- a/fs/proc/task_mmu.c
> > +++ b/fs/proc/task_mmu.c
> > @@ -25,7 +25,7 @@
> >
> > void task_mem(struct seq_file *m, struct mm_struct *mm)
> > {
> > - unsigned long text, lib, swap, ptes, pmds, anon, file, shmem;
> > + unsigned long text, lib, swap, ptes, pmds, puds, anon, file, shmem;
> > unsigned long hiwater_vm, total_vm, hiwater_rss, total_rss;
> >
> > anon = get_mm_counter(mm, MM_ANONPAGES);
> > @@ -51,6 +51,7 @@ void task_mem(struct seq_file *m, struct mm_struct *mm)
> > swap = get_mm_counter(mm, MM_SWAPENTS);
> > ptes = PTRS_PER_PTE * sizeof(pte_t) * atomic_long_read(&mm->nr_ptes);
> > pmds = PTRS_PER_PMD * sizeof(pmd_t) * mm_nr_pmds(mm);
> > + puds = PTRS_PER_PUD * sizeof(pmd_t) * mm_nr_puds(mm);
>
> ^ pud_t ?
Ouch. Thanks for spotting this.
Andrew, could you take this fixup:
diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index 0bf9e423aa99..627de66204bd 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -51,7 +51,7 @@ void task_mem(struct seq_file *m, struct mm_struct *mm)
swap = get_mm_counter(mm, MM_SWAPENTS);
ptes = PTRS_PER_PTE * sizeof(pte_t) * atomic_long_read(&mm->nr_ptes);
pmds = PTRS_PER_PMD * sizeof(pmd_t) * mm_nr_pmds(mm);
- puds = PTRS_PER_PUD * sizeof(pmd_t) * mm_nr_puds(mm);
+ puds = PTRS_PER_PUD * sizeof(pud_t) * mm_nr_puds(mm);
seq_printf(m,
"VmPeak:\t%8lu kB\n"
"VmSize:\t%8lu kB\n"
--
Kirill A. Shutemov
