The quilt patch titled Subject: dma/pool: do not complain if DMA pool is not allocated has been removed from the -mm tree. Its filename was dma-pool-do-not-complain-if-dma-pool-is-not-allocated.patch
This patch was dropped because an alternative patch was or shall be merged
------------------------------------------------------ From: Michal Hocko mhocko@suse.com Subject: dma/pool: do not complain if DMA pool is not allocated Date: Tue, 9 Aug 2022 17:37:59 +0200
We have a system complaining about order-10 allocation for the DMA pool.
[ 14.017417][ T1] swapper/0: page allocation failure: order:10, mode:0xcc1(GFP_KERNEL|GFP_DMA), nodemask=(null),cpuset=/,mems_allowed=0-7 [ 14.017429][ T1] CPU: 4 PID: 1 Comm: swapper/0 Not tainted 5.14.21-150400.22-default #1 SLE15-SP4 0b6a6578ade2de5c4a0b916095dff44f76ef1704 [ 14.017434][ T1] Hardware name: XXXX [ 14.017437][ T1] Call Trace: [ 14.017444][ T1] <TASK> [ 14.017449][ T1] dump_stack_lvl+0x45/0x57 [ 14.017469][ T1] warn_alloc+0xfe/0x160 [ 14.017490][ T1] __alloc_pages_slowpath.constprop.112+0xc27/0xc60 [ 14.017497][ T1] ? rdinit_setup+0x2b/0x2b [ 14.017509][ T1] ? rdinit_setup+0x2b/0x2b [ 14.017512][ T1] __alloc_pages+0x2d5/0x320 [ 14.017517][ T1] alloc_page_interleave+0xf/0x70 [ 14.017531][ T1] atomic_pool_expand+0x4a/0x200 [ 14.017541][ T1] ? rdinit_setup+0x2b/0x2b [ 14.017544][ T1] __dma_atomic_pool_init+0x44/0x90 [ 14.017556][ T1] dma_atomic_pool_init+0xad/0x13f [ 14.017560][ T1] ? __dma_atomic_pool_init+0x90/0x90 [ 14.017562][ T1] do_one_initcall+0x41/0x200 [ 14.017581][ T1] kernel_init_freeable+0x236/0x298 [ 14.017589][ T1] ? rest_init+0xd0/0xd0 [ 14.017596][ T1] kernel_init+0x16/0x120 [ 14.017599][ T1] ret_from_fork+0x22/0x30 [ 14.017604][ T1] </TASK> [...] [ 14.018026][ T1] Node 0 DMA free:160kB boost:0kB min:0kB low:0kB high:0kB reserved_highatomic:0KB active_anon:0kB inactive_anon:0kB active_file:0kB inactive_file:0kB unevictable:0kB writepending:0kB present:15996kB managed:15360kB mlocked:0kB bounce:0kB free_pcp:0kB local_pcp:0kB free_cma:0kB [ 14.018035][ T1] lowmem_reserve[]: 0 0 0 0 0 [ 14.018339][ T1] Node 0 DMA: 0*4kB 0*8kB 0*16kB 1*32kB (U) 0*64kB 1*128kB (U) 0*256kB 0*512kB 0*1024kB 0*2048kB 0*4096kB = 160kB
The usable memory in the DMA zone is obviously too small for the pool pre-allocation. The allocation failure raises concern by admins because this is considered an error state.
In fact the preallocation itself doesn't expose any actual problem. It is not even clear whether anybody is ever going to use this pool. If yes then a warning will be triggered anyway.
Silence the warning to prevent confusion and bug reports.
Link: https://lkml.kernel.org/r/YvJ/V2bor9Q3P6ov@dhcp22.suse.cz Signed-off-by: Michal Hocko mhocko@suse.com Reviewed-by: Baoquan He bhe@redhat.com Cc: Christoph Hellwig hch@lst.de Cc: John Donnelly john.p.donnelly@oracle.com Cc: David Hildenbrand david@redhat.com Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org ---
kernel/dma/pool.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/kernel/dma/pool.c~dma-pool-do-not-complain-if-dma-pool-is-not-allocated +++ a/kernel/dma/pool.c @@ -205,7 +205,7 @@ static int __init dma_atomic_pool_init(v ret = -ENOMEM; if (has_managed_dma()) { atomic_pool_dma = __dma_atomic_pool_init(atomic_pool_size, - GFP_KERNEL | GFP_DMA); + GFP_KERNEL | GFP_DMA | __GFP_NOWARN); if (!atomic_pool_dma) ret = -ENOMEM; } _
Patches currently in -mm which might be from mhocko@suse.com are