(CC: davem, soheil & gregkh) On 03/17/18 20:12, Holger Hoffstätte wrote: > On 03/17/18 19:41, Carlos Carvalho wrote: >> I've put 4.14.27 this morning in this machine and in about 2h it started >> showing null dereferences identical to the following one. There were several of >> them, with about 1/2h of interval. Strangely it continued to work and I saw no >> other anomalies. I've just reverted to 4.14.26. >> >> It only happened in this machine, which has a net traffic of several Gb/s and >> thousands of simultaneous connections. >> >> Mar 17 13:29:21 sagres kernel: : BUG: unable to handle kernel NULL pointer dereference at 0000000000000038 >> Mar 17 13:29:21 sagres kernel: : IP: tcp_push+0x4e/0xe7 >> Mar 17 13:29:21 sagres kernel: : PGD 0 P4D 0 >> Mar 17 13:29:21 sagres kernel: : Oops: 0002 [#1] SMP PTI >> Mar 17 13:29:21 sagres kernel: : CPU: 55 PID: 2658 Comm: apache2 Not tainted 4.14.27 #4 (snip) > > Fixed by: https://www.spinics.net/lists/netdev/msg489445.html > > -h > This patch is in the netdev patchwork at https://patchwork.ozlabs.org/patch/886324/ but has been marked as "not applicable" without further queued/rejected comment from Dave, so I believe it became a victim of email lossage. As the patch says it doesn't apply to anything older than 4.14, but it has been tested & reported by several people as fixing the problem, and indeed works fine. Since GregKH only accepts net patches from Dave I wanted to make sure it got queued up for 4.14. Thanks, Holger