On Mon, Jun 05, 2023 at 09:11:07PM +0100, Lorenzo Stoakes wrote: > In __vmalloc_area_node() we always warn_alloc() when an allocation > performed by vm_area_alloc_pages() fails unless it was due to a pending > fatal signal. > > However, huge page allocations instigated either by vmalloc_huge() or > __vmalloc_node_range() (or a caller that invokes this like kvmalloc() or > kvmalloc_node()) always falls back to order-0 allocations if the huge page > allocation fails. > > This renders the warning useless and noisy, especially as all callers > appear to be aware that this may fallback. This has already resulted in at > least one bug report from a user who was confused by this (see link). > > Therefore, simply update the code to only output this warning for order-0 > pages when no fatal signal is pending. > > Link: https://bugzilla.suse.com/show_bug.cgi?id=1211410 > Signed-off-by: Lorenzo Stoakes <lstoakes@xxxxxxxxx> > --- > mm/vmalloc.c | 17 +++++++++++++---- > 1 file changed, 13 insertions(+), 4 deletions(-) > > diff --git a/mm/vmalloc.c b/mm/vmalloc.c > index ab606a80f475..e563f40ad379 100644 > --- a/mm/vmalloc.c > +++ b/mm/vmalloc.c > @@ -3149,11 +3149,20 @@ static void *__vmalloc_area_node(struct vm_struct *area, gfp_t gfp_mask, > * allocation request, free them via vfree() if any. > */ > if (area->nr_pages != nr_small_pages) { > - /* vm_area_alloc_pages() can also fail due to a fatal signal */ > - if (!fatal_signal_pending(current)) > + /* > + * vm_area_alloc_pages() can fail due to insufficient memory but > + * also:- > + * > + * - a pending fatal signal > + * - insufficient huge page-order pages > + * > + * Since we always retry allocations at order-0 in the huge page > + * case a warning for either is spurious. > + */ > + if (!fatal_signal_pending(current) && page_order == 0) > warn_alloc(gfp_mask, NULL, > - "vmalloc error: size %lu, page order %u, failed to allocate pages", > - area->nr_pages * PAGE_SIZE, page_order); > + "vmalloc error: size %lu, failed to allocate pages", > + area->nr_pages * PAGE_SIZE); > goto fail; > } > > -- > 2.40.1 > Reviewed-by: Uladzislau Rezki (Sony) <urezki@xxxxxxxxx>
