我试图找出内存不足问题的原因。我有一个内核。我正在尝试构建（信息：从飞思卡尔 SabreSD 到 Solidrun Hummingboard，版本 3.10，android 发行版）。我的系统有512MB物理内存。
我的内核使用这个虚拟内存布局启动：
Memory: 447MB 64MB = 511MB total
Memory: 238916k/238916k available, 285372k reserved, 0K highmem
Virtual kernel memory layout:
vector : 0xffff0000 - 0xffff1000 ( 4 kB)
fixmap : 0xfff00000 - 0xfffe0000 ( 896 kB)
vmalloc : 0xa0800000 - 0xff000000 (1512 MB)
lowmem : 0x80000000 - 0xa0000000 ( 512 MB)
pkmap : 0x7fe00000 - 0x80000000 ( 2 MB)
modules : 0x7f000000 - 0x7fe00000 ( 14 MB)
.text : 0x80008000 - 0x80e7a48c (14794 kB)
.init : 0x80e7b000 - 0x80ed0600 ( 342 kB)
.data : 0x80ed2000 - 0x80f56000 ( 528 kB)
.bss : 0x80f56000 - 0x80feacf8 ( 596 kB)
使用以下虚拟内存布局启动工作的3.0.35 内核时：
Memory: 431MB = 431MB total
Memory: 424264k/424264k available, 100024k reserved, 31744K highmem
Virtual kernel memory layout:
vector : 0xffff0000 - 0xffff1000 ( 4 kB)
fixmap : 0xfff00000 - 0xfffe0000 ( 896 kB)
DMA : 0xfbe00000 - 0xffe00000 ( 64 MB)
vmalloc : 0xd9800000 - 0xf2000000 ( 392 MB)
lowmem : 0xc0000000 - 0xd9000000 ( 400 MB)
pkmap : 0xbfe00000 - 0xc0000000 ( 2 MB)
modules : 0xbf000000 - 0xbfe00000 ( 14 MB)
.init : 0xc0008000 - 0xc0049000 ( 260 kB)
.text : 0xc0049000 - 0xc0994048 (9517 kB)
.data : 0xc0996000 - 0xc0a38858 ( 651 kB)
.bss : 0xc0a3887c - 0xc0bc3af0 (1581 kB)
据我了解，vmalloc 区域太大，lowmem 匹配物理可用内存。我的假设对吗？我应该看什么样的配置？
我试图了解我应该对内核或引导加载程序进行哪些配置更改以修改此内存映射（如果我猜它真的是错误的）。内核忽略命令行vmalloc参数（目前默认是400M，可能是因为至少配置了这么大）。内存布局是在 KConfig 中的某处配置还是在 Uboot 中初始化？你能帮我找出正确的地方吗？
编辑
将 CONFIG_VMSPLIT_2G 更改为 CONFIG_VMSPLIT_3G 后，我可以看到以下内存映射：
Memory: 447MB 64MB = 511MB total
Memory: 238884k/238884k available, 285404k reserved, 0K highmem
Virtual kernel memory layout:
vector : 0xffff0000 - 0xffff1000 ( 4 kB)
fixmap : 0xfff00000 - 0xfffe0000 ( 896 kB)
vmalloc : 0xe0800000 - 0xff000000 ( 488 MB)
lowmem : 0xc0000000 - 0xe0000000 ( 512 MB)
pkmap : 0xbfe00000 - 0xc0000000 ( 2 MB)
modules : 0xbf000000 - 0xbfe00000 ( 14 MB)
.text : 0xc0008000 - 0xc0e7a48c (14794 kB)
.init : 0xc0e7b000 - 0xc0ed0600 ( 342 kB)
.data : 0xc0ed2000 - 0xc0f56000 ( 528 kB)
.bss : 0xc0f56000 - 0xc0feacf8 ( 596 kB)
但是我在初始化中仍然有一个“内存不足”异常。
这是启动日志的详细信息：
request_suspend_state: wakeup (3->0) at 6224194667 (1970-01-01 00:00:05.154978000 UTC)
init: untracked pid 240 killed by signal 9
request_suspend_state: wakeup (0->0) at 10022039001 (1970-01-01 00:00:08.952822334 UTC)
init: untracked pid 287 killed by signal 9
request_suspend_state: wakeup (0->0) at 14912863668 (1970-01-01 00:00:13.843647334 UTC)
init: untracked pid 332 killed by signal 9
request_suspend_state: wakeup (0->0) at 20705884002 (1970-01-01 00:00:19.636667335 UTC)
init: untracked pid 376 killed by signal 9
request_suspend_state: wakeup (0->0) at 26695295003 (1970-01-01 00:00:25.626078336 UTC)
init: untracked pid 411 killed by signal 9
request_suspend_state: wakeup (0->0) at 31950397337 (1970-01-01 00:00:30.881180670 UTC)
init: untracked pid 454 killed by signal 9
request_suspend_state: wakeup (0->0) at 37370094004 (1970-01-01 00:00:36.300875670 UTC)
init: untracked pid 490 exited with status 1
request_suspend_state: wakeup (0->0) at 42182273338 (1970-01-01 00:00:41.113056337 UTC)
init: untracked pid 535 killed by signal 9
request_suspend_state: wakeup (0->0) at 47580075672 (1970-01-01 00:00:46.510858671 UTC)
netd invoked oom-killer: gfp_mask=0x2084d0, order=0, oom_score_adj=-1000
CPU: 0 PID: 588 Comm: netd Not tainted 3.10.53-g4f0dd92 #1
[<c0013fc8>] (unwind_backtrace+0x0/0xf8) from [<c00118f4>] (show_stack+0x10/0x14)
[<c00118f4>] (show_stack+0x10/0x14) from [<c07d9e28>] (dump_header.isra.10+0x6c/0x194)
[<c07d9e28>] (dump_header.isra.10+0x6c/0x194) from [<c00a8418>] (out_of_memory+0x29c/0x2d4)
[<c00a8418>] (out_of_memory+0x29c/0x2d4) from [<c00ac20c>] (__alloc_pages_nodemask+0x834/0x85c)
[<c00ac20c>] (__alloc_pages_nodemask+0x834/0x85c) from [<c00c16c0>] (__pte_alloc+0x24/0x13c)
[<c00c16c0>] (__pte_alloc+0x24/0x13c) from [<c00c4724>] (handle_mm_fault+0xdc/0xf0)
[<c00c4724>] (handle_mm_fault+0xdc/0xf0) from [<c00c490c>] (__get_user_pages+0x110/0x424)
[<c00c490c>] (__get_user_pages+0x110/0x424) from [<c00e2c20>] (get_arg_page+0x50/0xb4)
[<c00e2c20>] (get_arg_page+0x50/0xb4) from [<c00e2d88>] (copy_strings+0x104/0x260)
[<c00e2d88>] (copy_strings+0x104/0x260) from [<c00e2f04>] (copy_strings_kernel+0x20/0x28)
[<c00e2f04>] (copy_strings_kernel+0x20/0x28) from [<c00e4718>] (do_execve+0x3d8/0x4b8)
[<c00e4718>] (do_execve+0x3d8/0x4b8) from [<c00e4a0c>] (SyS_execve+0x30/0x44)
[<c00e4a0c>] (SyS_execve+0x30/0x44) from [<c000e0c0>] (ret_fast_syscall+0x0/0x30)
Mem-info:
DMA per-cpu:
CPU 0: hi: 90, btch: 15 usd: 22
CPU 1: hi: 90, btch: 15 usd: 42
active_anon:55770 inactive_anon:3 isolated_anon:0
active_file:650 inactive_file:1024 isolated_file:0
unevictable:342 dirty:0 writeback:0 unstable:0
free:30058 slab_reclaimable:733 slab_unreclaimable:1420
mapped:870 shmem:9 pagetables:263 bounce:0
free_cma:29780
DMA free:120232kB min:1952kB low:2440kB high:2928kB active_anon:223224kB inactive_anon:12kB active_file:2600kB inactive_file:4168kB unevictable:1368kB isolated(anon):0kB isolated(file):0kB present:523264kB managed:238884kB mlocked:0kB dirty:0kB writeback:0kB mapped:3532kB shmem:36kB slab_reclaimable:2932kB slab_unreclaimable:5680kB kernel_stack:880kB pagetables:1052kB unstable:0kB bounce:0kB free_cma:119120kB writeback_tmp:0kB pages_scanned:9097 all_unreclaimable? yes
lowmem_reserve[]: 0 0 0 0
DMA: 2124*4kB (UC) 2122*8kB (MC) 2124*16kB (UC) 1875*32kB (UMC) 1*64kB (M) 0*128kB 0*256kB 0*512kB 0*1024kB 0*2048kB 0*4096kB 0*8192kB 0*16384kB 0*32768kB = 119520kB
2181 total pagecache pages
0 pages in swap cache
Swap cache stats: add 0, delete 0, find 0/0
Free swap = 0kB
Total swap = 0kB
131072 pages of RAM
29928 free pages
5552 reserved pages
1542 slab pages
2939 pages shared
0 pages swap cached
[ pid ] uid tgid total_vm rss nr_ptes swapents oom_score_adj name
[ 134] 0 134 655 109 4 0 -1000 ueventd
[ 135] 0 135 654 30 4 0 -1000 watchdogd
[ 146] 1036 146 3060 186 8 0 -1000 logd
[ 147] 0 147 922 73 4 0 -1000 healthd
[ 148] 0 148 1118 121 4 0 -1000 lmkd
[ 149] 1000 149 812 124 3 0 -1000 servicemanager
[ 150] 0 150 2445 196 7 0 -1000 vold
[ 153] 0 153 1228 241 4 0 -1000 debuggerd
[ 154] 1019 154 3495 307 8 0 -1000 drmserver
[ 156] 1012 156 801 68 3 0 -1000 installd
[ 157] 1017 157 1571 144 5 0 -1000 keystore
[ 158] 0 158 1310 165 4 0 -1000 rild
[ 161] 1023 161 2317 119 6 0 -1000 sdcard
[ 163] 2000 163 1935 32 6 0 -1000 adbd
[ 402] 0 402 32816 17695 48 0 -1000 main
[ 444] 0 444 30768 15807 46 0 -1000 main
[ 487] 0 487 29744 13571 41 0 -1000 main
[ 528] 0 528 29744 7304 31 0 -1000 main
[ 583] 0 583 1103 148 4 0 -1000 netd
[ 584] 1000 584 2173 286 5 0 -1000 surfaceflinger
[ 585] 1013 585 3026 619 7 0 -1000 mediaserver
[ 586] 0 586 2168 356 6 0 -1000 app_process
[ 588] 0 588 1103 91 4 0 -1000 netd
Kernel panic - not syncing: Out of memory and no killable processes...
CPU0: stopping
CPU: 0 PID: 528 Comm: main Not tainted 3.10.53-g4f0dd92 #1
[<c0013fc8>] (unwind_backtrace+0x0/0xf8) from [<c00118f4>] (show_stack+0x10/0x14)
[<c00118f4>] (show_stack+0x10/0x14) from [<c0013214>] (handle_IPI+0x178/0x1a4)
[<c0013214>] (handle_IPI+0x178/0x1a4) from [<c0008564>] (gic_handle_irq+0x54/0x5c)
[<c0008564>] (gic_handle_irq+0x54/0x5c) from [<c000de7c>] (__irq_usr+0x3c/0x60)
Exception stack(0xc3ff3fb0 to 0xc3ff3ff8)
3fa0: f9ab7147 b61cf1a0 00000000 f8d0b34a
3fc0: b5324c28 b5324c28 b5325360 b61cf1a0 00000000 00000000 b5325300 b5310400
3fe0: b6eca758 be809c00 b6ce96a1 b6cda996 200e3430 ffffffff
Rebooting in 5 seconds..
知道我内存不足的原因吗？