On Sun, 14 Feb 2016, Marc MERLIN wrote: > I was able to make one bcache ok, but when trying to make a 2nd one > where I only have a backing device, I'm getting repeated page allocation > failures. > > Just to be clear, this is what I want to do: every new HD backed device > will have bcache on top even if I don't have a cache device for it, so > that I can add bcache later. > Is it something reasonable to do? Setup partitions as bcache backing > devices without a cache device for them? > > So right now, I'm trying to do > md5 - bcache - dmcrypt - btrfs > > So I did > make-bcache -B /dev/md5 > echo /dev/md5 > /sys/fs/bcache/register > > and it fails: > bash: page allocation failure: order:4, mode:0x2040d0 > CPU: 2 PID: 28043 Comm: bash Not tainted 4.3.3-amd64-i915-volpreempt-20150421 #2 Do you have the bcache stability patches? 4.3.3 might be missing some critical patches. Be sure to cherry-pick these from linux 4.5-rc1: git cherry-pick 2ef9ccbf~1..627ccd20 or use one of the 4.1 or 3.18 longterm kernels. I've not see any memory allocation issues before in bcache, but you definitely want those patches for general stability. -Eric > Hardware name: System manufacturer System Product Name/P8H67-M PRO, BIOS 3904 04/27/2013 > 0000000000000000 ffff88006f65ba78 ffffffff8134150e 0000000000000001 > ffff88006f65bb10 ffffffff8111f6ce ffff88021f5f4e38 00000004002040d0 > 0000000400000040 0000000000000286 0000000000000004 0000000000000040 > Call Trace: > [<ffffffff8134150e>] dump_stack+0x44/0x55 > [<ffffffff8111f6ce>] warn_alloc_failed+0x111/0x129 > [<ffffffff811220f8>] __alloc_pages_nodemask+0x6ae/0x70d > [<ffffffff8115fb98>] kmem_getpages+0x6a/0x162 > [<ffffffff8115fd89>] fallback_alloc+0xf9/0x193 > [<ffffffff8115ff46>] ____cache_alloc_node+0x123/0x130 > [<ffffffff81160f1e>] __kmalloc+0xf8/0x175 > [<ffffffffc057e141>] ? kzalloc.constprop.22+0xe/0x10 [bcache] > [<ffffffffc057e141>] kzalloc.constprop.22+0xe/0x10 [bcache] > [<ffffffffc0580986>] register_bcache+0x61b/0x1452 [bcache] > [<ffffffff81342ce0>] kobj_attr_store+0x10/0x1a > [<ffffffff811d9677>] sysfs_kf_write+0x39/0x3b > [<ffffffff811d8f79>] kernfs_fop_write+0xed/0x130 > [<ffffffff81177a05>] __vfs_write+0x26/0xa5 > [<ffffffff816c0fdd>] ? _raw_spin_lock+0xe/0x10 > [<ffffffff81179277>] ? fput+0x16/0x88 > [<ffffffff812cd113>] ? security_file_permission+0x3b/0x42 > [<ffffffff8108e79b>] ? percpu_down_read+0x14/0x46 > [<ffffffff81179ba7>] ? __sb_start_write+0x25/0x3c > [<ffffffff81178067>] vfs_write+0xa2/0xe6 > [<ffffffff81178835>] SyS_write+0x4d/0x78 > [<ffffffff816c3962>] sysenter_dispatch+0xf/0x29 > Mem-Info: > active_anon:412014 inactive_anon:222645 isolated_anon:0 > active_file:461209 inactive_file:499016 isolated_file:0 > unevictable:1166 dirty:28999 writeback:712 unstable:0 > slab_reclaimable:69514 slab_unreclaimable:47678 > mapped:420280 shmem:410182 pagetables:5369 bounce:0 > free:131404 free_pcp:1088 free_cma:0 > Node 0 DMA free:15888kB min:20kB low:24kB high:28kB active_anon:0kB inactive_anon:0kB active_file:0kB inactive_file:0kB unevictable:0kB isolated(anon):0kB isolated(file):0kB present:15976kB managed:15892kB mlocked:0kB dirty:0kB writeback:0kB mapped:0kB shmem:0kB slab_reclaimable:0kB slab_unreclaimable:4kB kernel_stack:0kB pagetables:0kB unstable:0kB bounce:0kB free_pcp:0kB local_pcp:0kB free_cma:0kB writeback_tmp:0kB pages_scanned:0 all_unreclaimable? yes > lowmem_reserve[]: 0 3203 7674 7674 > Node 0 DMA32 free:462160kB min:4644kB low:5804kB high:6964kB active_anon:443844kB inactive_anon:470452kB active_file:755044kB inactive_file:897988kB unevictable:1488kB isolated(anon):0kB isolated(file):0kB present:3362068kB managed:3283400kB mlocked:1488kB dirty:21656kB writeback:2912kB mapped:703428kB shmem:665604kB slab_reclaimable:71416kB slab_unreclaimable:69108kB kernel_stack:7056kB pagetables:6732kB unstable:0kB bounce:0kB free_pcp:3008kB local_pcp:0kB free_cma:0kB writeback_tmp:0kB pages_scanned:0 all_unreclaimable? no > lowmem_reserve[]: 0 0 4471 4471 > Node 0 Normal free:26576kB min:6480kB low:8100kB high:9720kB active_anon:1199644kB inactive_anon:420120kB active_file:1091280kB inactive_file:1101072kB unevictable:3176kB isolated(anon):0kB isolated(file):0kB present:4708352kB managed:4578508kB mlocked:3176kB dirty:78692kB writeback:8900kB mapped:977740kB shmem:975112kB slab_reclaimable:206628kB slab_unreclaimable:124308kB kernel_stack:5120kB pagetables:14888kB unstable:0kB bounce:0kB free_pcp:3364kB local_pcp:0kB free_cma:0kB writeback_tmp:0kB pages_scanned:0 all_unreclaimable? no > lowmem_reserve[]: 0 0 0 0 > Node 0 DMA: 0*4kB 0*8kB 1*16kB (U) 0*32kB 2*64kB (U) 1*128kB (U) 1*256kB (U) 0*512kB 1*1024kB (U) 1*2048kB (M) 3*4096kB (M) = 15888kB > Node 0 DMA32: 79732*4kB (UEM) 17590*8kB (UEM) 151*16kB (UM) 1*32kB (U) 0*64kB 0*128kB 0*256kB 0*512kB 0*1024kB 0*2048kB 0*4096kB = 462096kB > Node 0 Normal: 4435*4kB (UEM) 5*8kB (UE) 0*16kB 0*32kB 0*64kB 0*128kB 0*256kB 0*512kB 0*1024kB 0*2048kB 0*4096kB = 17780kB > Node 0 hugepages_total=0 hugepages_free=0 hugepages_surp=0 hugepages_size=2048kB > 1387415 total pagecache pages > 11051 pages in swap cache > Swap cache stats: add 4480800, delete 4469749, find 1201429612/1202240702 > Free swap = 14096744kB > Total swap = 15616764kB > 2021599 pages RAM > 0 pages HighMem/MovableOnly > 52149 pages reserved > 4096 pages cma reserved > 0 pages hwpoisoned > bcache: register_bcache() error opening /dev/md5: (null) > > Any idea what's going on? > > gargamel:~# free > total used free shared buffers cached > Mem: 7877800 6065272 1812528 0 224 4193616 > -/+ buffers/cache: 1871432 6006368 > Swap: 15616764 1519056 14097708 > gargamel:~# cat /proc/meminfo > MemTotal: 7877800 kB > MemFree: 1799936 kB > MemAvailable: 4602768 kB > Buffers: 224 kB > Cached: 4208328 kB > SwapCached: 44472 kB > Active: 3595380 kB > Inactive: 1508064 kB > Active(anon): 1647420 kB > Inactive(anon): 891972 kB > Active(file): 1947960 kB > Inactive(file): 616092 kB > Unevictable: 4664 kB > Mlocked: 4664 kB > SwapTotal: 15616764 kB > SwapFree: 14097712 kB > Dirty: 104932 kB > Writeback: 0 kB > AnonPages: 876480 kB > Mapped: 1679836 kB > Shmem: 1640716 kB > Slab: 469492 kB > SReclaimable: 280564 kB > SUnreclaim: 188928 kB > KernelStack: 12288 kB > PageTables: 21264 kB > NFS_Unstable: 0 kB > Bounce: 0 kB > WritebackTmp: 0 kB > CommitLimit: 19555664 kB > Committed_AS: 7995116 kB > VmallocTotal: 34359738367 kB > VmallocUsed: 409412 kB > VmallocChunk: 34358947836 kB > HardwareCorrupted: 0 kB > AnonHugePages: 0 kB > CmaTotal: 16384 kB > CmaFree: 232 kB > HugePages_Total: 0 > HugePages_Free: 0 > HugePages_Rsvd: 0 > HugePages_Surp: 0 > Hugepagesize: 2048 kB > DirectMap4k: 740628 kB > DirectMap2M: 7346176 kB > > Thanks, > Marc > -- > "A mouse is a device used to point at the xterm you want to type in" - A.S.R. > Microsoft is to operating systems .... > .... what McDonalds is to gourmet cooking > Home page: http://marc.merlins.org/ | PGP 1024R/763BE901 > -- > To unsubscribe from this list: send the line "unsubscribe linux-bcache" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- Eric Wheeler, President eWheeler, Inc. dba Global Linux Security 888-LINUX26 (888-546-8926) Fax: 503-716-3878 PO Box 25107 www.GlobalLinuxSecurity.pro Linux since 1996! Portland, OR 97298 -- To unsubscribe from this list: send the line "unsubscribe linux-bcache" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html