我得到一个“无法处理内核分页请求”内核oops（请参阅下面的错误消息），我看不出原因。据我所知，当我访问我不应访问的内存时会出现此错误消息。但在这种情况下，错误消息似乎在分配后/中直接触发。
所以我的问题是：是否有另一个原因导致这种情况发生？
以下是错误消息：
[ 68.229185] Unable to handle kernel paging request at virtual address 5761308c
[ 68.236398] pgd = c0004000
[ 68.239094] [5761308c] *pgd=00000000
[ 68.242670] Internal error: Oops: 5 [#1] SMP ARM
[ 68.247266] Modules linked in: riddler(O)
[ 68.251285] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G W O 4.1.0 #14
[ 68.258388] Hardware name: Altera SOCFPGA
[ 68.262380] task: c07cffa8 ti: c07ca000 task.ti: c07ca000
[ 68.267763] PC is at kmem_cache_alloc_trace+0x60/0x184
[ 68.272883] LR is at riddler_nf_queue_handler+0x164/0x6d4 [riddler]
[ 68.279122] pc : [<c0118ea0>] lr : [<bf000630>] psr: 200f0113
[ 68.279122] sp : c07cbb80 ip : c07cbbc0 fp : c07cbbbc
[ 68.290546] r10: 00000000 r9 : ed66d800 r8 : 0000000c
[ 68.295746] r7 : edc01f00 r6 : bf000630 r5 : 00008020 r4 : 5761308c
[ 68.302243] r3 : 00000000 r2 : c07cbb80 r1 : c07cbce0 r0 : 2da0f000
[ 68.308741] Flags: nzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment kernel
[ 68.316015] Control: 10c5387d Table: 2cd3004a DAC: 00000015
[ 68.321734] Process swapper/0 (pid: 0, stack limit = 0xc07ca218)
[ 68.327713] Stack: (0xc07cbb80 to 0xc07cc000)
[ 68.332054] bb80: 000005dc c0448cdc c07cc404 00004058 2d66e000 ed5c99d0 bf001cfc ed5a8800
[ 68.340196] bba0: bf001cfc 000005c0 ed66d800 00000000 c07cbc14 c07cbbc0 bf000630 c0118e4c
[ 68.348338] bbc0: c07cbc9c 00000044 c07cbc14 c07cbbd8 00000000 00000000 00000001 00484c68
[ 68.356479] bbe0: 000005c0 0000001c 00000044 ed5a8800 c05b83f0 00000044 bf001984 edfebe40
[ 68.364621] bc00: bf001940 00000000 c07cbc64 c07cbc18 c0484e3c bf0004d8 c07cbc3c 00000000
[ 68.372762] bc20: 80000000 c04bbc02 ede3f000 00000000 00000000 c0489f30 c0483d08 c07cbc9c
[ 68.380903] bc40: edfebe40 c07cbc6c c07cdae8 00000003 ede3f000 c07cd524 c07cbc94 c07cbc68
[ 68.389045] bc60: c0483da8 c0484d00 edc817c0 bf001940 c07c9340 00000050 ecc91340 edfebe40
[ 68.397186] bc80: ede3f000 00000008 c07cbcd4 c07cbc98 c048a880 c0483d54 c07cbccc 00000000
[ 68.405327] bca0: 80000000 c04bbc02 ede3f000 00000000 00000000 c0489f30 edfebe40 c07ce898
[ 68.413468] bcc0: c048a4c4 ede3f000 c07cbd24 c07cbcd8 c0457b00 c048a4d0 00000000 ede3f000
[ 68.421610] bce0: edfebe40 ede3f580 00000020 edfebe40 00000000 ede3f05c c07cbd14 c07cd514
[ 68.429752] bd00: edfebe40 ede3f580 00000020 00000100 00000000 00000001 c07cbd3c c07cbd28
[ 68.437893] bd20: c045a34c c0457440 c07cd514 edfebe40 c07cbd6c c07cbd40 c045a400 c045a320
[ 68.446034] bd40: 2690390a 14562ba2 edfebe40 ede3f580 00000020 00000100 00000003 edfebe40
[ 68.454175] bd60: c07cbd8c c07cbd70 c045ada8 c045a3b4 ede3f580 edfebe40 000005ea 00000020
[ 68.462316] bd80: c07cbdec c07cbd90 c03a50c8 c045acec 00000000 e2d32d80 0000000f ee1d5400
[ 68.470456] bda0: 00000001 ede3f4c0 c07cbde4 c07cbdb8 c07d153c 00000100 00000040 00000002
[ 68.478597] bdc0: ffffffff ede3f580 00000001 00000040 0000012c ee1d8b80 c07cc100 c07cbe18
[ 68.486738] bde0: c07cbe54 c07cbdf0 c045be80 c03a4e04 ffffa577 c06b2a60 c07cd514 c07cd514
[ 68.494880] be00: c082ce31 ee1d8b80 c082f608 2da0f000 c07c9b80 ffffa579 c07cbe18 c07cbe18
[ 68.503021] be20: c07cbe20 c07cbe20 00000001 c07cc08c 00000003 00000000 00000100 c07ca000
[ 68.511163] be40: 00000008 c082cf0c c07cbebc c07cbe58 c002a684 c045bc68 00000011 edd41180
[ 68.519304] be60: edd411e0 00200000 c07cc100 ffffa578 c05769b4 0000000a c08302c0 c07c52c8
[ 68.527445] be80: c07cc080 c07cbe58 0000000c 00000004 00000000 c07c7c2c 00000024 00000000
[ 68.535587] bea0: 00000000 edc10800 c07cc450 c05769a8 c07cbed4 c07cbec0 c002ab68 c002a5a0
[ 68.543728] bec0: c07c7c2c 00000024 c07cbefc c07cbed8 c006738c c002aaec fee0010c c07cce2c
[ 68.551870] bee0: c07cbf20 fee00100 c082d4c0 c07cc450 c07cbf1c c07cbf00 c0009470 c0067328
[ 68.560011] bf00: c0010648 600f0013 ffffffff c07cbf54 c07cbf74 c07cbf20 c0014680 c0009448
[ 68.568153] bf20: 00000000 00000000 000198a0 c0021be0 00000000 c07ca000 c07cc49c ffffffff
[ 68.576295] bf40: c082d4c0 c07cc450 c05769a8 c07cbf74 c07cbf78 c07cbf68 c0010644 c0010648
[ 68.584437] bf60: 600f0013 ffffffff c07cbf9c c07cbf78 c005db84 c001060c 00000000 c082cc99
[ 68.592578] bf80: c07c5304 c07cbf78 c0570680 ffffffff c07cbfac c07cbfa0 c056be78 c005d9f4
[ 68.600719] bfa0: c07cbff4 c07cbfb0 c0763cc0 c056bdfc ffffffff ffffffff c07636d8 00000000
[ 68.608861] bfc0: 00000000 c07a98c8 00000000 c082fc14 c07cc440 c07a98c4 c07d1218 0000406a
[ 68.617002] bfe0: 413fc090 00000000 00000000 c07cbff8 0000807c c0763978 00000000 00000000
[ 68.625154] [<c0118ea0>] (kmem_cache_alloc_trace) from [<bf000630>] (riddler_nf_queue_handler+0x164/0x6d4 [riddler])
[ 68.635638] [<bf000630>] (riddler_nf_queue_handler [riddler]) from [<c0484e3c>] (nf_queue+0x148/0x17c)
[ 68.644907] [<c0484e3c>] (nf_queue) from [<c0483da8>] (nf_hook_slow+0x60/0xfc)
[ 68.652104] [<c0483da8>] (nf_hook_slow) from [<c048a880>] (ip_rcv+0x3bc/0x4c4)
[ 68.659308] [<c048a880>] (ip_rcv) from [<c0457b00>] (__netif_receive_skb_core+0x6cc/0x874)
[ 68.667542] [<c0457b00>] (__netif_receive_skb_core) from [<c045a34c>] (__netif_receive_skb+0x38/0x94)
[ 68.676724] [<c045a34c>] (__netif_receive_skb) from [<c045a400>] (netif_receive_skb_internal+0x58/0xcc)
[ 68.686077] [<c045a400>] (netif_receive_skb_internal) from [<c045ada8>] (napi_gro_receive+0xc8/0xf4)
[ 68.695176] [<c045ada8>] (napi_gro_receive) from [<c03a50c8>] (stmmac_poll+0x2d0/0x644)
[ 68.703148] [<c03a50c8>] (stmmac_poll) from [<c045be80>] (net_rx_action+0x224/0x354)
[ 68.710864] [<c045be80>] (net_rx_action) from [<c002a684>] (__do_softirq+0xf0/0x304)
[ 68.718577] [<c002a684>] (__do_softirq) from [<c002ab68>] (irq_exit+0x88/0xc0)
[ 68.725774] [<c002ab68>] (irq_exit) from [<c006738c>] (__handle_domain_irq+0x70/0xc4)
[ 68.733575] [<c006738c>] (__handle_domain_irq) from [<c0009470>] (gic_handle_irq+0x34/0x6c)
[ 68.741893] [<c0009470>] (gic_handle_irq) from [<c0014680>] (__irq_svc+0x40/0x54)
[ 68.749340] Exception stack(0xc07cbf20 to 0xc07cbf68)
[ 68.754371] bf20: 00000000 00000000 000198a0 c0021be0 00000000 c07ca000 c07cc49c ffffffff
[ 68.762512] bf40: c082d4c0 c07cc450 c05769a8 c07cbf74 c07cbf78 c07cbf68 c0010644 c0010648
[ 68.770650] bf60: 600f0013 ffffffff
[ 68.774133] [<c0014680>] (__irq_svc) from [<c0010648>] (arch_cpu_idle+0x48/0x4c)
[ 68.781508] [<c0010648>] (arch_cpu_idle) from [<c005db84>] (cpu_startup_entry+0x19c/0x264)
[ 68.789743] [<c005db84>] (cpu_startup_entry) from [<c056be78>] (rest_init+0x88/0x8c)
[ 68.797465] [<c056be78>] (rest_init) from [<c0763cc0>] (start_kernel+0x354/0x360)
[ 68.804917] Code: e7914000 e3540000 0a000038 e5973014 (e7949003)
[ 68.811024] ---[ end trace 11b433a852b633dc ]---
这是导致它的代码段（我想，我使用gdb“list *（riddler_nf_queue_handler）+ 0x164”来找到它）：
new = (struct fpga_kfifo_entry *) kzalloc(sizeof(struct fpga_kfifo_entry), GFP_ATOMIC);
new->entry = entry;
new->dma_buffer = dma_buffer; //+0x164 is here
new->dma_buffer_size = data_length_pad;
if(!(kfifo_put(&irq_fifo, new))) {
// FIFO was full
#ifdef DEBUG
pr_info("IRQ Fifo is full, couldn't add new entry!\n");
#endif
kfree(dma_buffer);
kfree(new);
nf_reinject(entry, NF_DROP);
return 0;
}
dma_buffer在同一个函数中分配，但更早：
data_length_pad = round_to_word_size(data_length + 1);
dma_buffer = (unsigned char *) kzalloc(data_length_pad, GFP_ATOMIC);
if (!dma_buffer) {
kfree(dma_buffer);
nf_reinject(entry, NF_DROP);
return 0;
} else {
// Only continue when allocation was successful
dma_buffer[data_length_pad - 1] = (unsigned char) data_length_pad - data_length;
}
提前致谢！