On Wed, Dec 5, 2018 at 4:08 AM Rafael David Tinoco rafael.tinoco@linaro.org wrote:
On 12/5/18 4:58 AM, Greg Kroah-Hartman wrote:
On Tue, Dec 04, 2018 at 07:09:46PM -0200, Rafael David Tinoco wrote:
On 12/4/18 8:48 AM, Greg Kroah-Hartman wrote:
This is the start of the stable review cycle for the 4.19.7 release. There are 139 patches in this series, all will be posted as a response to this one. If anyone has any issues with these being applied, please let me know.
Responses should be made by Thu Dec 6 10:36:22 UTC 2018. Anything received after that time might be too late.
The whole patch series can be found in one patch at: https://www.kernel.org/pub/linux/kernel/v4.x/stable-review/patch-4.19.7-rc1.... or in the git tree and branch at: git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git linux-4.19.y and the diffstat can be found below.
thanks,
greg k-h
During functional tests for this v4.19 release, we faced a PANIC, described bellow, but unlikely related to this specific v4.19 version.
First a WARN() at tcp_output.c:
tcp_send_loss_probe(): ... /* Retransmit last segment. */ if (WARN_ON(!skb)) goto rearm_timer; ...
[ 173.557528] WARNING: CPU: 1 PID: 0 at /srv/oe/build/tmp-rpb-glibc/work-shared/juno/kernel-source/net/ipv4/tcp_output.c:2485 tcp_send_loss_probe+0x164/0x1e8 [ 173.571425] Modules linked in: crc32_ce crct10dif_ce fuse [ 173.576804] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.19.7-rc1 #1 [ 173.583014] Hardware name: ARM Juno development board (r2) (DT)
So only this one machine saw this failure?
If you can reproduce it again, bisection would be great to do if possible.
Yes, the only machine... I'm afraid this issue is intermittent and depends on TCP Tail Loss and a specific race causing the NULL dereference, so bisection would be tricky since it has happened independently of the functional test that was running. I have also copied authors for the Tail Loss code to check if they got any clues even without KASAN data.
There cause is an inconsistency of packet accounting: TCP retransmission queue is empty but tp->packets_out is not zero. We will send a fix soon. Thanks.
Thank you,
Rafael D. Tinoco