From: Michal Hocko <mhocko@xxxxxxxx> Subject: mm: make slab and vmalloc allocators __GFP_NOLOCKDEP aware sl?b and vmalloc allocators reduce the given gfp mask for their internal needs. For that they use GFP_RECLAIM_MASK to preserve the reclaim behavior and constrains. __GFP_NOLOCKDEP is not a part of that mask because it doesn't really control the reclaim behavior strictly speaking. On the other hand it tells the underlying page allocator to disable reclaim recursion detection so arguably it should be part of the mask. Having __GFP_NOLOCKDEP in the mask will not alter the behavior in any form so this change is safe pretty much by definition. It also adds a support for this flag to SL?B and vmalloc allocators which will in turn allow its use to kvmalloc as well. A lack of the support has been noticed recently in http://lkml.kernel.org/r/20211119225435.GZ449541@xxxxxxxxxxxxxxxxxxx Link: https://lkml.kernel.org/r/YZ9XtLY4AEjVuiEI@xxxxxxxxxxxxxx Signed-off-by: Michal Hocko <mhocko@xxxxxxxx> Reported-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx> Acked-by: Dave Chinner <dchinner@xxxxxxxxxx> Acked-by: Vlastimil Babka <vbabka@xxxxxxx> Cc: Christoph Hellwig <hch@xxxxxx> Cc: Dave Chinner <david@xxxxxxxxxxxxx> Cc: Ilya Dryomov <idryomov@xxxxxxxxx> Cc: Jeff Layton <jlayton@xxxxxxxxxx> Cc: Neil Brown <neilb@xxxxxxx> Cc: Uladzislau Rezki (Sony) <urezki@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/internal.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/mm/internal.h~mm-make-slab-and-vmalloc-allocators-__gfp_nolockdep-aware +++ a/mm/internal.h @@ -21,7 +21,7 @@ #define GFP_RECLAIM_MASK (__GFP_RECLAIM|__GFP_HIGH|__GFP_IO|__GFP_FS|\ __GFP_NOWARN|__GFP_RETRY_MAYFAIL|__GFP_NOFAIL|\ __GFP_NORETRY|__GFP_MEMALLOC|__GFP_NOMEMALLOC|\ - __GFP_ATOMIC) + __GFP_ATOMIC|__GFP_NOLOCKDEP) /* The GFP flags allowed during early boot */ #define GFP_BOOT_MASK (__GFP_BITS_MASK & ~(__GFP_RECLAIM|__GFP_IO|__GFP_FS)) _
