On 4/29/24 7:47 AM, Christoph Hellwig wrote: > This loses flags like GFP_NOFS and GFP_NOIO that are important to avoid > deadlocks as well as GFP_NOLOCKDEP that otherwise generates lockdep false > positives. GFP_NOFS and GFP_NOIO translate to GFP_KERNEL without __GFP_FS/__GFP_IO so I don't see how this patch would have helped with those. __GFP_NOLOCKDEP is likely the actual issue and stackdepot solved it like this: https://lore.kernel.org/linux-xfs/20240418141133.22950-1-ryabinin.a.a@xxxxxxxxx/ So we could just do the same here. > Fixes: 217b2119b9e2 ("mm,page_owner: implement the tracking of the stacks count") > Reported-by: Reported-by: syzbot+b7e8d799f0ab724876f9@xxxxxxxxxxxxxxxxxxxxxxxxx > Signed-off-by: Christoph Hellwig <hch@xxxxxx> > --- > mm/page_owner.c | 2 -- > 1 file changed, 2 deletions(-) > > diff --git a/mm/page_owner.c b/mm/page_owner.c > index d17d1351ec84af..d214488846fa92 100644 > --- a/mm/page_owner.c > +++ b/mm/page_owner.c > @@ -168,9 +168,7 @@ static void add_stack_record_to_list(struct stack_record *stack_record, > unsigned long flags; > struct stack *stack; > > - /* Filter gfp_mask the same way stackdepot does, for consistency */ > gfp_mask &= ~GFP_ZONEMASK; > - gfp_mask &= (GFP_ATOMIC | GFP_KERNEL); > gfp_mask |= __GFP_NOWARN; > > set_current_in_page_owner();
