Bug 200991 - iwlwifi: "BUG: scheduling while atomic" on wrong credential for WPA2-EAP hotspot
Summary: iwlwifi: "BUG: scheduling while atomic" on wrong credential for WPA2-EAP hotspot
Status: CLOSED PATCH_ALREADY_AVAILABLE
Alias: None
Product: Drivers
Classification: Unclassified
Component: network-wireless (show other bugs)
Hardware: All Linux
: P1 normal
Assignee: DO NOT USE - assign "network-wireless-intel" component instead
URL:
Keywords:
: 201297 201355 (view as bug list)
Depends on:
Blocks:
 
Reported: 2018-09-01 18:03 UTC by hexchain
Modified: 2019-01-10 06:00 UTC (History)
5 users (show)

See Also:
Kernel Version: 4.18.5-arch1-1-ARCH
Subsystem:
Regression: No
Bisected commit-id:


Attachments
relevant lines from journalctl -b (59.16 KB, text/plain)
2018-09-01 18:03 UTC, hexchain
Details
iwlwifi scheduling while atomic, dmesg output (23.06 KB, application/pgp-encrypted)
2018-10-30 17:19 UTC, Florian Kargl
Details

Description hexchain 2018-09-01 18:03:15 UTC
Created attachment 278231 [details]
relevant lines from journalctl -b

When connecting to an Eduroam hotspot with wrong credentials, iwlwifi prints out lots of (scary) error messages, followed by a hardware restart.

The distro is Arch Linux, and a relevant log file is attached.
Comment 1 Luca Coelho 2018-09-28 10:49:04 UTC
Do you have any idea if this was happening before 4.18?

Can you try our core39 release, as explained in our wiki[1] and see if the problem still happens with that?

We had a bunch of changes in the IRQ rx handler recently, so the problem may be solved in our internal tree already.

[1] https://wireless.wiki.kernel.org/en/users/drivers/iwlwifi/core_release
Comment 2 hexchain 2018-09-28 13:23:20 UTC
No idea, but I'll give a try with LTS 4.14.72.

I will also try core39 release. The new -41 firmware is also needed, right?
Comment 3 hexchain 2018-10-01 12:32:24 UTC
Here's some test result:

1. The issue does not happen (no "BUG" line or stack traces) on 4.14.72 but is reproducible on 4.18.11.

2. The issue also does not happen with the new core39 release and -41 firmware.

3. The "Unhandled alg: 0x707" line appears in all cases.

Test method:

Using 123456/123456 as username/password, and TTLS/MSCHAPv2 as the authentication mechanism for a WPA2-EAP Eduroam hotspot. In my case, the hotspot is provided by some Cisco device.
Comment 4 hexchain 2018-10-01 12:37:45 UTC
As a side note, the scripts/uninstall.sh in backport-iwlwifi does not support xz compression for kernel modules.
Comment 5 Luca Coelho 2018-10-12 11:00:48 UTC
Thanks for the initial analysis, we'll try to find if there's any patch that fixes it in core39.
Comment 6 Johannes Berg 2018-10-12 11:03:29 UTC
(In reply to Haochen Tong from comment #4)
> As a side note, the scripts/uninstall.sh in backport-iwlwifi does not
> support xz compression for kernel modules.

Fixed that in upstream backports, it'll take a while to propagate to backport-iwlwifi, but it eventually will.

Thanks for the report!
Comment 7 Luca Coelho 2018-10-13 06:19:38 UTC
Thanks, Johannes! I'll pull your fix into our core release soon, during my next round of merging back from upstream.

The patch that fixes this "scheduling while atomic" issue is already in net-next.git[1] and should go to 4.20.  When it reaches 4.20 it will be automatically backported to the relevant stable kernels.  I could have sent it to the 4.19-rc series, but since it's not a regression in 4.19, I preferred to send it to -next instead.

[1] https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git/commit/?id=3baf7528d6f832b28622d1ddadd2e47f6c2b5e08
Comment 8 Luca Coelho 2018-10-13 06:33:19 UTC
*** Bug 201297 has been marked as a duplicate of this bug. ***
Comment 9 Luca Coelho 2018-10-13 06:33:40 UTC
*** Bug 201355 has been marked as a duplicate of this bug. ***
Comment 10 Florian Kargl 2018-10-30 17:19:18 UTC
Created attachment 279255 [details]
iwlwifi scheduling while atomic, dmesg output

Just ran into a similar issue while trying to connect to eduroam, although with correct credentials (stored in password manager). I know it's been fixed already, but more data can't hurt.

Debian 4.18.10-2,
iwlwifi-7260-17.ucode,
firmware version: 17.948900127.0

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