Как понять это сообщение об ошибке dmesg?
Я написал этот простой модуль для управления устройством и вызова некоторых из его методов управления питанием, таких как.suspend а также.resume, При его инициализации модуль просто ищет конкретное устройство и пытается вызвать его методы.
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/pci.h>
static int __init mfps_driver_init(void){
struct pci_dev *dev = NULL;
struct pci_driver *driver = NULL;
struct device *device = NULL;
dev = pci_get_device(0x8086, 0x15a2, NULL);
if((dev == NULL) || (dev == 0)){
printk(KERN_INFO "LEONZO: NOTHING FOUND SIZE %ld\n", sizeof(dev));
} else {
driver = dev->driver;
printk(KERN_INFO "LEONZO: I FOUND THE DEVICE OF THE SIZE %ld\n", sizeof(dev));
printk(KERN_INFO "LEONZO: HERE IS ITS DRIVER NAME %s\n", driver->name);
printk(KERN_INFO "LEONZO: CALLING IT SUSPEND METHOD\n");
*device = dev->dev;
device_lock(device);
device_unlock(device);
}
return 0;
}
static void __exit mfps_driver_exit(void){
}
module_init(mfps_driver_init);
module_exit(mfps_driver_exit);
Код успешно скомпилирован. Но я получаю ошибку ядра при загрузке модуля:
sudo insmod MyFirstPowerState.ko
И Dmesg показывают следующий вывод
[ 59.545180] MyFirstPowerState: module license 'unspecified' taints kernel.
[ 59.545183] Disabling lock debugging due to kernel taint
[ 59.546010] LEONZO: I FOUND THE DEVICE OF THE SIZE 8
[ 59.546012] LEONZO: HERE IS ITS DRIVER NAME e1000e
[ 59.546013] LEONZO: CALLING IT SUSPEND METHOD
[ 59.546021] BUG: unable to handle kernel NULL pointer dereference at (null)
[ 59.546051] IP: [<ffffffffc011907e>] mfps_driver_init+0x7e/0x1000 [MyFirstPowerState]
[ 59.546077] PGD 0
[ 59.546085] Oops: 0002 [#1] SMP
[ 59.546097] Modules linked in: MyFirstPowerState(POE+) xt_CHECKSUM arc4 iwlmvm mac80211 snd_hda_codec_hdmi snd_hda_codec_realtek iwlwifi snd_hda_codec_generic rtsx_pci_ms memstick cfg80211 nf_conntrack_netbios_ns nf_conntrack_broadcast ipt_MASQUERADE nf_nat_masquerade_ipv4 xt_tcpudp ip6t_REJECT nf_reject_ipv6 ipt_REJECT nf_reject_ipv4 xt_conntrack ebtable_nat ebtable_broute bridge stp llc ebtable_filter ebtables ip6table_nat nf_conntrack_ipv6 nf_defrag_ipv6 nf_nat_ipv6 ip6table_mangle ip6table_security ip6table_raw ip6table_filter ip6_tables iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 nf_nat nf_conntrack iptable_mangle iptable_security iptable_raw iptable_filter ip_tables x_tables dm_crypt hp_wmi sparse_keymap intel_rapl iosf_mbi x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel kvm crct10dif_pclmul dm_multipath crc32_pclmul scsi_dh aesni_intel aes_x86_64 lrw gf128mul glue_helper ablk_helper cryptd joydev serio_raw lpc_ich uvcvideo snd_seq_midi snd_seq_midi_event snd_rawmidi snd_hda_intel snd_hda_controller snd_hda_codec videobuf2_vmalloc snd_hwdep shpchp snd_pcm videobuf2_memops videobuf2_core v4l2_common snd_seq e1000e(OE) i915_bpo ptp mei_me pps_core mei videodev media snd_seq_device intel_ips snd_timer drm_kms_helper drm btusb snd i2c_algo_bit soundcore 8250_fintek hp_accel lis3lv02d input_polldev tpm_infineon hp_wireless mac_hid parport_pc ppdev lp parport rfcomm bnep bluetooth binfmt_misc btrfs xor raid6_pq dm_mirror dm_region_hash dm_log uas usb_storage hid_generic usbhid hid rtsx_pci_sdmmc ahci psmouse libahci rtsx_pci wmi video
[ 59.546577] CPU: 1 PID: 4180 Comm: insmod Tainted: P OE 3.19.0-51-generic #58~14.04.1-Ubuntu
[ 59.546613] Hardware name: Hewlett-Packard HP EliteBook 840 G2/2216, BIOS M71 Ver. 01.05 03/26/2015
[ 59.546648] task: ffff880241a7b110 ti: ffff880242f68000 task.ti: ffff880242f68000
[ 59.546678] RIP: 0010:[<ffffffffc011907e>] [<ffffffffc011907e>] mfps_driver_init+0x7e/0x1000 [MyFirstPowerState]
[ 59.546720] RSP: 0018:ffff880242f6bd18 EFLAGS: 00010246
[ 59.546741] RAX: 0000000000000000 RBX: ffff880245b4d000 RCX: 00000000000000ae
[ 59.546772] RDX: 0000000000000000 RSI: ffff880245b4d098 RDI: 0000000000000000
[ 59.546807] RBP: ffff880242f6bd28 R08: 000000000000000a R09: 0000000000000000
[ 59.546839] R10: 0000000000000d53 R11: ffff880242f6b9de R12: ffffffffc06a8000
[ 59.546868] R13: 0000000000000000 R14: ffffffffc0119000 R15: ffff880242f6bef8
[ 59.546900] FS: 00007f8787aa6740(0000) GS:ffff88024f440000(0000) knlGS:0000000000000000
[ 59.546921] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 59.546936] CR2: 0000000000000000 CR3: 0000000244393000 CR4: 00000000003407e0
[ 59.546955] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 59.546978] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 59.547006] Stack:
[ 59.547014] ffffffff81c1d060 ffff880204cd3280 ffff880242f6bda8 ffffffff81002144
[ 59.547046] 0000000000000001 0000000000000002 ffff8801f8ddc4c0 0000000000000001
[ 59.547079] ffff880242f6bd88 ffffffff811cef19 ffffffff810f7aac 0000000000000018
[ 59.547114] Call Trace:
[ 59.547131] [<ffffffff81002144>] do_one_initcall+0xd4/0x210
[ 59.547162] [<ffffffff811cef19>] ? kmem_cache_alloc_trace+0x199/0x220
[ 59.547194] [<ffffffff810f7aac>] ? load_module+0x164c/0x1cc0
[ 59.547222] [<ffffffff810f7ae5>] load_module+0x1685/0x1cc0
[ 59.547247] [<ffffffff810f3380>] ? store_uevent+0x40/0x40
[ 59.547274] [<ffffffff810f8296>] SyS_finit_module+0x86/0xb0
[ 59.547298] [<ffffffff817b788d>] system_call_fastpath+0x16/0x1b
[ 59.547314] Code: c7 80 c0 4b c0 31 c0 e8 19 14 69 c1 48 c7 c7 a8 c0 4b c0 31 c0 e8 0b 14 69 c1 31 c0 48 8d b3 98 00 00 00 b9 ae 00 00 00 48 89 c7 <f3> a5 bf 60 00 00 00 e8 26 c7 69 c1 bf 60 00 00 00 e8 ac c5 69
[ 59.547393] RIP [<ffffffffc011907e>] mfps_driver_init+0x7e/0x1000 [MyFirstPowerState]
[ 59.547416] RSP <ffff880242f6bd18>
[ 59.547425] CR2: 0000000000000000
[ 59.554577] ---[ end trace 42e3b1c73677cdfa ]---
Я также заметил, что поэтому невозможно удалить модуль:
sudo rmmod MyFirstPowerState.ko
rmmod: ERROR: Module MyFirstPowerState is in use
Любая идея о том, что этот код означает и как исправить ошибку?