On Tue, Nov 5, 2019 at 9:06 AM Thibaut Sautereau <thibaut.sautereau@xxxxxxxxxxx> wrote: > > On Mon, Nov 04, 2019 at 09:33:18AM -0800, Eric Dumazet wrote: > > > > > > On 11/4/19 9:03 AM, Thibaut Sautereau wrote: > > > > > > We first encountered this issue under huge network traffic (system image > > > download), and I was able to reproduce by simply sending a big packet > > > with `ping -s 65507 <ip>`, which crashes the kernel every single time. > > > > > > > Since you have a repro, could you start a bisection ? > > From my previous email: > > "Bisection points to the following commit: 1b7e816fc80e ("mm: slub: > Fix slab walking for init_on_free"), and indeed the BUG is not > triggered when init_on_free is disabled." > > Or are you meaning something else? Could you please give more specific reproduction steps? I've checked out v5.3.8 from git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git, ran `make defconfig` and added CONFIG_SLUB_DEBUG_ON=y. Then I've built the kernel, ran it on QEMU with slub_debug=F and init_on_free=1, SSHed into the machine and executed `ping -s 65507 127.0.0.1` This however didn't trigger any crashes. Am I missing something? > -- > Thibaut Sautereau > CLIP OS developer -- Alexander Potapenko Software Engineer Google Germany GmbH Erika-Mann-Straße, 33 80636 München Geschäftsführer: Paul Manicle, Halimah DeLaine Prado Registergericht und -nummer: Hamburg, HRB 86891 Sitz der Gesellschaft: Hamburg