On Wed, Apr 03, 2019 at 10:00:38AM +0800, kernel test robot wrote: > Greetings, > > 0day kernel testing robot got the below dmesg and the first bad commit is > > https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master > > commit 15c8410c67adefd26ea0df1f1b86e1836051784b > Author: Tobin C. Harding <tobin@xxxxxxxxxx> > AuthorDate: Fri Mar 29 10:01:23 2019 +1100 > Commit: Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx> > CommitDate: Sat Mar 30 16:09:41 2019 +1100 > > mm/slob.c: respect list_head abstraction layer > > Currently we reach inside the list_head. This is a violation of the layer > of abstraction provided by the list_head. It makes the code fragile. > More importantly it makes the code wicked hard to understand. > > The code logic is based on the page in which an allocation was made, we > want to modify the slob_list we are working on to have this page at the > front. We already have a function to check if an entry is at the front of > the list. Recently a function was added to list.h to do the list > rotation. We can use these two functions to reduce line count, reduce > code fragility, and reduce cognitive load required to read the code. > > Use list_head functions to interact with lists thereby maintaining the > abstraction provided by the list_head structure. > > Link: http://lkml.kernel.org/r/20190318000234.22049-3-tobin@xxxxxxxxxx > Signed-off-by: Tobin C. Harding <tobin@xxxxxxxxxx> > Cc: Christoph Lameter <cl@xxxxxxxxx> > Cc: David Rientjes <rientjes@xxxxxxxxxx> > Cc: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx> > Cc: Pekka Enberg <penberg@xxxxxxxxxx> > Cc: Roman Gushchin <guro@xxxxxx> > Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> > Signed-off-by: Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx> > > 2e1f88301e include/linux/list.h: add list_rotate_to_front() > 15c8410c67 mm/slob.c: respect list_head abstraction layer > 05d08e2995 Add linux-next specific files for 20190402 > +-------------------------------------------------------+------------+------------+---------------+ > | | 2e1f88301e | 15c8410c67 | next-20190402 | > +-------------------------------------------------------+------------+------------+---------------+ > | boot_successes | 1009 | 198 | 299 | > | boot_failures | 0 | 2 | 44 | > | WARNING:at_lib/list_debug.c:#__list_add_valid | 0 | 2 | 44 | > | RIP:__list_add_valid | 0 | 2 | 44 | > | WARNING:at_lib/list_debug.c:#__list_del_entry_valid | 0 | 2 | 25 | > | RIP:__list_del_entry_valid | 0 | 2 | 25 | > | WARNING:possible_circular_locking_dependency_detected | 0 | 2 | 44 | > | RIP:_raw_spin_unlock_irqrestore | 0 | 2 | 2 | > | BUG:kernel_hang_in_test_stage | 0 | 0 | 6 | > | BUG:unable_to_handle_kernel | 0 | 0 | 1 | > | Oops:#[##] | 0 | 0 | 1 | > | RIP:slob_page_alloc | 0 | 0 | 1 | > | Kernel_panic-not_syncing:Fatal_exception | 0 | 0 | 1 | > | RIP:delay_tsc | 0 | 0 | 2 | > +-------------------------------------------------------+------------+------------+---------------+ > > [ 2.618737] db_root: cannot open: /etc/target > [ 2.620114] mtdoops: mtd device (mtddev=name/number) must be supplied > [ 2.620967] slram: not enough parameters. > [ 2.621614] ------------[ cut here ]------------ > [ 2.622254] list_add corruption. prev->next should be next (ffffffffaeeb71b0), but was ffffcee1406d3f70. (prev=ffffcee140422508). Is this perhaps a false positive because we hackishly move the list_head 'head' and insert it back into the list. Perhaps this is confusing the validation functions? Tobin
