Hi heiko, On Mon, Oct 15, 2018 at 1:54 PM Pingfan Liu <kernelfans@xxxxxxxxx> wrote: > > On Tue, Oct 9, 2018 at 2:35 PM Heiko Carstens <heiko.carstens@xxxxxxxxxx> wrote: > > > > Hello, > > > > with linux-next for 20181008 I can reliably crash my system with lot's of > > debugging options enabled on s390. List debugging triggers the list > > corruption below, which I could bisect down to this commit: > > > > fde06e07750477f049f12d7d471ffa505338a3e7 is the first bad commit > > commit fde06e07750477f049f12d7d471ffa505338a3e7 > > Author: Pingfan Liu <kernelfans@xxxxxxxxx> > > Date: Thu Oct 4 07:43:01 2018 +1000 > > > > mm/slub: remove useless condition in deactivate_slab > > > > The var l should be used to reflect the original list, on which the page > > should be. But c->page is not on any list. Furthermore, the current code > > does not update the value of l. Hence remove the related logic > > > > Link: http://lkml.kernel.org/r/1537941430-16217-1-git-send-email-kernelfans@xxxxxxxxx > > Signed-off-by: Pingfan Liu <kernelfans@xxxxxxxxx> > > Acked-by: Christoph Lameter <cl@xxxxxxxxx> > > Cc: Pekka Enberg <penberg@xxxxxxxxxx> > > Cc: David Rientjes <rientjes@xxxxxxxxxx> > > Cc: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx> > > Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> > > Signed-off-by: Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx> > > > > list_add double add: new=000003d1029ecc08, prev=000000008ff846d0,next=000003d1029ecc08. > > ------------[ cut here ]------------ > > kernel BUG at lib/list_debug.c:31! > > illegal operation: 0001 ilc:1 [#1] PREEMPT SMP > > Modules linked in: > > CPU: 3 PID: 106 Comm: (sd-executor) Not tainted 4.19.0-rc6-00291-gfde06e077504 #21 > > Hardware name: IBM 2964 NC9 702 (z/VM 6.4.0) > > Krnl PSW : (____ptrval____) (____ptrval____) (__list_add_valid+0x98/0xa8) > > R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:1 PM:0 RI:0 EA:3 > > Krnl GPRS: 0000000074311fdf 0000000080000001 0000000000000058 0000000000e7b8b2 > > 0000000000000000 0000000075438c64 00000000a7b31928 001c007b00000000 > > 000000008fe99d00 00000000a7b31b40 000003d1029ecc08 00000000a7c03a80 > > 000003d1029ecc08 000000008ff84680 00000000007b5674 00000000a7c03960 > > Krnl Code: 00000000007b5668: c0200034734a larl %r2,e43cfc > > 00000000007b566e: c0e5ffd0cf51 brasl %r14,1cf510 > > #00000000007b5674: a7f40001 brc 15,7b5676 > > >00000000007b5678: a7290001 lghi %r2,1 > > 00000000007b567c: ebcff0a00004 lmg %r12,%r15,160(%r15) > > 00000000007b5682: 07fe bcr 15,%r14 > > 00000000007b5684: 0707 bcr 0,%r7 > > 00000000007b5686: 0707 bcr 0,%r7 > > Call Trace: > > ([<00000000007b5674>] __list_add_valid+0x94/0xa8) > > [<000000000037d30e>] deactivate_slab.isra.15+0x45e/0x810 > > [<000000000037ede4>] ___slab_alloc+0x76c/0x7c0 > > [<000000000037eeb0>] __slab_alloc.isra.16+0x78/0xa8 > > [<00000000003808c8>] kmem_cache_alloc+0x160/0x458 > > [<0000000000141a3a>] vm_area_dup+0x3a/0x60 > > [<0000000000142f0a>] copy_process+0xd72/0x2100 > > [<000000000014449a>] _do_fork+0xba/0x688 > > [<0000000000144bb0>] sys_clone+0x48/0x50 > > [<0000000000b8faf0>] system_call+0xd8/0x2d0 > > INFO: lockdep is turned off. > > Last Breaking-Event-Address: > > [<00000000007b5674>] __list_add_valid+0x94/0xa8 > > > > Kernel panic - not syncing: Fatal exception: panic_on_oops > > > > Sorry that just see this email, and reply late. > I think it is caused by the uinon page->lru and page->next. It can be fixed by: > diff --git a/include/linux/slub_def.h b/include/linux/slub_def.h > index 3a1a1db..4aa0fb5 100644 > --- a/include/linux/slub_def.h > +++ b/include/linux/slub_def.h > @@ -56,6 +56,7 @@ struct kmem_cache_cpu { > #define slub_set_percpu_partial(c, p) \ > ({ \ > slub_percpu_partial(c) = (p)->next; \ > + p->next = NULL; \ > }) > > I will do some test and post the fix. > Please ignore the above comment. And after re-check the code, I am sure that all callers of deactivate_slab(), pass c->page, which means that page should not be on any list. But your test result "list_add double add: new=000003d1029ecc08, prev=000000008ff846d0,next=000003d1029ecc08" indicates that page(new) is already on a list. I think that maybe something else is wrong which is covered. I can not reproduce this bug on x86. Could you share your config and cmdline? Any do you turn on any debug option of slub? Thanks, Pingfan
