On Mon, Jun 20, 2016 at 9:50 PM, Sasha Levin <sasha.levin@xxxxxxxxxx> wrote: > On 06/20/2016 08:53 AM, Alexander Potapenko wrote: >> On Sun, Jun 19, 2016 at 7:40 PM, Sasha Levin <sasha.levin@xxxxxxxxxx> wrote: >>> > On 06/19/2016 03:24 AM, Alexander Potapenko wrote: >>>> >> Hi Sasha, >>>> >> >>>> >> This commit delays the reuse of memory after it has been freed, so >>>> >> it's intended to help people find more use-after-free errors. >>> > >>> > Is there a way to tell if the use-after-free access was to a memory >>> > that is quarantined? >>> > >>>> >> But I'm puzzled why the stacks are missing. >>> > >>> > I looked at the logs, it looks like stackdepot ran out of room pretty >>> > early during boot. >> This is quite strange, as there's room for ~80k stacks in the depot, >> and usually the number of unique stacks is lower than 30k. >> I wonder if this is specific to your config, can you please share it >> (assuming you're using ToT kernel)? >> Attached is the patch that you can try out to dump the new stacks >> after 30k - it's really interesting where do they come from (note the >> patch is not for submission). > > Attached a log file generated with that patch, and my kernel config. I haven't looked close yet, but your log contains 1455 unique 'DRIVERNAME_driver_init' function names, for which it's quite likely that 80k allocation stacks are generated. Can you remove the dump_stack() call from my patch, fuzz for a while and see to which number does |alloc_cnt| converge on your machine? Maybe our estimate was just too optimistic, and we need to increase the memory limit for the stack depot. > > Thanks, > Sasha > -- Alexander Potapenko Software Engineer Google Germany GmbH Erika-Mann-Straße, 33 80636 München Geschäftsführer: Matthew Scott Sucherman, Paul Terence Manicle Registergericht und -nummer: Hamburg, HRB 86891 Sitz der Gesellschaft: Hamburg -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href