Arch Linux

sunnyraj

Member

Registered: 2015-01-19

Posts: 3

Wifi with stock kernel driver rtl8192ce not working consistently

Hi,

My wifi card RTL8188CE does not work consistently with kernel driver rlt8192ce. The problem that i observe is that after some time ~1hr wifi devices get disconnected and are not able to reconnect. On restarting wifi using systemctl restart hostapd sometimes the system hangs.

Here are the outputs.

        03:00.0 Network controller: Realtek Semiconductor Co., Ltd. RTL8188CE 802.11b/g/n WiFi Adapter (rev 01)
	Subsystem: ASUSTeK Computer Inc. Device 84b5
	Kernel driver in use: rtl8192ce
	Kernel modules: rtl8192ce

Logs

Jan 22 19:30:56 Blitz-4 kernel: DMA: Out of SW-IOMMU space for 105 bytes at device 0000:05:00.0
Jan 22 19:30:56 Blitz-4 kernel: [color=red]rtl8192ce 0000:05:00.0: swiotlb buffer is full (sz: 105 bytes)[/color]
Jan 22 19:30:56 Blitz-4 kernel: DMA: Out of SW-IOMMU space for 105 bytes at device 0000:05:00.0
Jan 22 19:30:56 Blitz-4 kernel: rtl8192ce 0000:05:00.0: swiotlb buffer is full (sz: 105 bytes)
Jan 22 19:30:56 Blitz-4 kernel: DMA: Out of SW-IOMMU space for 105 bytes at device 0000:05:00.0
Jan 22 19:30:57 Blitz-4 kernel: rtl8192ce 0000:05:00.0: swiotlb buffer is full (sz: 105 bytes)
Jan 22 19:30:57 Blitz-4 kernel: DMA: Out of SW-IOMMU space for 105 bytes at device 0000:05:00.0
Jan 22 19:30:57 Blitz-4 kernel: rtl8192ce 0000:05:00.0: swiotlb buffer is full (sz: 105 bytes)
Jan 22 19:30:57 Blitz-4 kernel: DMA: Out of SW-IOMMU space for 105 bytes at device 0000:05:00.0
Jan 22 19:30:57 Blitz-4 kernel: DMA: Out of SW-IOMMU space for 105 bytes at device 0000:05:00.0
Jan 22 19:30:57 Blitz-4 kernel: DMA: Out of SW-IOMMU space for 9100 bytes at device 0000:05:00.0
Jan 22 19:30:57 Blitz-4 kernel: DMA: Out of SW-IOMMU space for 105 bytes at device 0000:05:00.0
Jan 22 19:30:57 Blitz-4 kernel: DMA: Out of SW-IOMMU space for 105 bytes at device 0000:05:00.0
Jan 22 19:30:57 Blitz-4 kernel: DMA: Out of SW-IOMMU space for 105 bytes at device 0000:05:00.0
Jan 22 19:30:58 Blitz-4 kernel: BUG: unable to handle kernel paging request at 000060240000801d
Jan 22 19:30:58 Blitz-4 kernel: IP: [<ffffffff811b29a6>] __kmalloc+0x86/0x1c0
Jan 22 19:30:58 Blitz-4 kernel: PGD 0 
Jan 22 19:30:58 Blitz-4 kernel: Oops: 0000 [#1] PREEMPT SMP 
Jan 22 19:30:58 Blitz-4 kernel: Modules linked in: nls_iso8859_1 nls_cp437 vfat fat ctr ccm fuse bridge stp llc snd_hda_codec_hdmi arc4 mousedev hid_generic coretemp hwmon ppdev intel_rapl x86_pkg_temp_thermal intel_powerclamp kvm_intel rtl8192ce rtl_pci rtl8192c_common rtlwifi kvm mac80211 crct10dif_pclmul crc32_pclmul evdev crc32c_intel mac_hid uas ghash_clmulni_intel usb_storage usbhid cfg80211 hid snd_hda_codec_realtek snd_hda_codec_generic i915 aesni_intel iTCO_wdt iTCO_vendor_support aes_x86_64 lrw snd_hda_intel gf128mul drm_kms_helper rfkill snd_hda_controller glue_helper ablk_helper psmouse drm snd_hda_codec cryptd pcspkr serio_raw snd_hwdep intel_gtt snd_pcm i2c_i801 r8168(O) i2c_algo_bit i2c_core snd_timer parport_pc tpm_infineon snd fan thermal tpm_tis parport mei_me tpm soundcore battery mei video shpchp
Jan 22 19:30:58 Blitz-4 kernel:  button lpc_ich processor sch_fq_codel ext4 crc16 mbcache jbd2 sd_mod atkbd libps2 ahci libahci libata xhci_pci ehci_pci xhci_hcd ehci_hcd scsi_mod usbcore usb_common i8042 serio
Jan 22 19:30:58 Blitz-4 kernel:CPU: 3 PID: 1238 Comm: Cache2 I/O Tainted: G           O   3.18.2-2-ARCH #1

Please suggest any workaround/modules.

mike_nzk

Member

Registered: 2012-07-24

Posts: 14

Re: Wifi with stock kernel driver rtl8192ce not working consistently

Same problem to me. lspci output:

07:00.0 Network controller: Realtek Semiconductor Co., Ltd. RTL8188CE 802.11b/g/n WiFi Adapter (rev 01)

and logs:

Apr 04 16:06:29 nzk kernel: rtl8192ce 0000:07:00.0: swiotlb buffer is full (sz: 9100 bytes)
Apr 04 16:06:29 nzk kernel: DMA: Out of SW-IOMMU space for 9100 bytes at device 0000:07:00.0
Apr 04 16:06:29 nzk kernel: rtl8192ce 0000:07:00.0: swiotlb buffer is full (sz: 9100 bytes)
Apr 04 16:06:29 nzk kernel: DMA: Out of SW-IOMMU space for 9100 bytes at device 0000:07:00.0
Apr 04 16:06:29 nzk kernel: rtl8192ce 0000:07:00.0: swiotlb buffer is full (sz: 9100 bytes)
Apr 04 16:06:29 nzk kernel: DMA: Out of SW-IOMMU space for 9100 bytes at device 0000:07:00.0
Apr 04 16:06:29 nzk kernel: rtl8192ce 0000:07:00.0: swiotlb buffer is full (sz: 9100 bytes)
Apr 04 16:06:29 nzk kernel: DMA: Out of SW-IOMMU space for 9100 bytes at device 0000:07:00.0

A bug report submitted to redhat bugzilla https://bugzilla.redhat.com/show_bug.cg … id=1203241 suggests it may be caused by a bug in the rtl8192ce kernel module since linux 3.17.7. I hope this problem could be solved as quickly as possible.

Last edited by mike_nzk (2015-04-04 08:33:59)

b4nst0n

Member

Registered: 2013-08-08

Posts: 50

Re: Wifi with stock kernel driver rtl8192ce not working consistently

Same problem here.
uname -r

3.19.2-1-ARCH

lspci

03:00.0 Network controller: Realtek Semiconductor Co., Ltd. RTL8188CE 802.11b/g/n WiFi Adapter (rev 01)

running mentohust and create_ap, system works fine about 20-40 minute, and it suddenly crash, everything freezing and I could only cold reboot.

Last edited by b4nst0n (2015-04-04 16:04:36)

lokesh987

Member

Registered: 2014-12-15

Posts: 43

Re: Wifi with stock kernel driver rtl8192ce not working consistently

Don't know whether this applies, my stock kernel driver was rtl8192cu.

I had similar problems using a wlan dongle with RTL8188CUS. The original Kernel driver is known to be buggy. An alternative exists:https://github.com/pvaret/rtl8192cu-fixes

mike_nzk

Member

Registered: 2012-07-24

Posts: 14

Re: Wifi with stock kernel driver rtl8192ce not working consistently

After upgrading to linux kernel 4.0.4, the driver causes a kernel panic immediately after hostapd starts to launch AP (with the same config). It seems that the driver is problematic all the time. Looking for a fix as soon as possible.

mike_nzk

Member

Registered: 2012-07-24

Posts: 14

Re: Wifi with stock kernel driver rtl8192ce not working consistently

This problem is still not fixed after upgrading to linux 4.1.2-2.

mike_nzk

Member

Registered: 2012-07-24

Posts: 14

Re: Wifi with stock kernel driver rtl8192ce not working consistently

This problem is still not fixed after upgrading to linux 4.1.6.

Head_on_a_Stick

Member

From: London

Registered: 2014-02-20

Posts: 7,732

Website

Re: Wifi with stock kernel driver rtl8192ce not working consistently

Looking for a fix as soon as possible.

Perform a git bisect and submit a patch then.
https://wiki.archlinux.org/index.php/Bisecting_bugs

---

Are you infected with Wetiko?

mike_nzk

Member

Registered: 2012-07-24

Posts: 14

Re: Wifi with stock kernel driver rtl8192ce not working consistently

This problem is finally fixed after upgrading to linux-lts 4.1.9-2.