On 4/16/19 4:10 PM, Thomas Gleixner wrote: > kstack_end() is broken on interrupt stacks as they are not guaranteed to be > sized THREAD_SIZE and THREAD_SIZE aligned. > > As SLAB seems not to be used much with debugging enabled and might just go > away completely according to: > > https://lkml.kernel.org/r/612f9b99-a75b-6aeb-cf92-7dc5421cd950@xxxxxxx > > just remove the bogus code instead of trying to fix it. > > Fixes: 98eb235b7feb ("[PATCH] page unmapping debug") - History tree > Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> > Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> > Cc: Pekka Enberg <penberg@xxxxxxxxxx> > Cc: linux-mm@xxxxxxxxx Acked-by: Vlastimil Babka <vbabka@xxxxxxx> Thanks. > --- > V5: Remove the cruft. > V4: Make it actually work > V2: Made the code simpler to understand (Andy) > --- > mm/slab.c | 22 +++------------------- > 1 file changed, 3 insertions(+), 19 deletions(-) > > --- a/mm/slab.c > +++ b/mm/slab.c > @@ -1470,33 +1470,17 @@ static bool is_debug_pagealloc_cache(str > static void store_stackinfo(struct kmem_cache *cachep, unsigned long *addr, > unsigned long caller) > { > - int size = cachep->object_size; > + int size = cachep->object_size / sizeof(unsigned long); > > addr = (unsigned long *)&((char *)addr)[obj_offset(cachep)]; > > - if (size < 5 * sizeof(unsigned long)) > + if (size < 4) > return; > > *addr++ = 0x12345678; > *addr++ = caller; > *addr++ = smp_processor_id(); > - size -= 3 * sizeof(unsigned long); > - { > - unsigned long *sptr = &caller; > - unsigned long svalue; > - > - while (!kstack_end(sptr)) { > - svalue = *sptr++; > - if (kernel_text_address(svalue)) { > - *addr++ = svalue; > - size -= sizeof(unsigned long); > - if (size <= sizeof(unsigned long)) > - break; > - } > - } > - > - } > - *addr++ = 0x87654321; > + *addr = 0x87654321; > } > > static void slab_kernel_map(struct kmem_cache *cachep, void *objp, >
