Re: [PATCH] mm/page_alloc: silence a KASAN false positive

2020-06-30 Thread Vasily Gorbik
On Wed, Jun 10, 2020 at 08:26:00AM -0400, Qian Cai wrote: > On Wed, Jun 10, 2020 at 07:54:50AM +0200, Dmitry Vyukov wrote: > > On Wed, Jun 10, 2020 at 7:22 AM Qian Cai wrote: > > > > > > kernel_init_free_pages() will use memset() on s390 to clear all pages > > > from kmalloc_order() which will

Re: [PATCH] mm/page_alloc: silence a KASAN false positive

2020-06-23 Thread Heiko Carstens
On Wed, Jun 10, 2020 at 08:26:00AM -0400, Qian Cai wrote: > On Wed, Jun 10, 2020 at 07:54:50AM +0200, Dmitry Vyukov wrote: > > On Wed, Jun 10, 2020 at 7:22 AM Qian Cai wrote: > > > > > > kernel_init_free_pages() will use memset() on s390 to clear all pages > > > from kmalloc_order() which will

Re: [PATCH] mm/page_alloc: silence a KASAN false positive

2020-06-10 Thread Qian Cai
On Wed, Jun 10, 2020 at 01:02:04PM +0200, Alexander Potapenko wrote: > On Wed, Jun 10, 2020 at 7:55 AM Dmitry Vyukov wrote: > > > > On Wed, Jun 10, 2020 at 7:22 AM Qian Cai wrote: > > > > > > kernel_init_free_pages() will use memset() on s390 to clear all pages > > > from kmalloc_order() which

Re: [PATCH] mm/page_alloc: silence a KASAN false positive

2020-06-10 Thread Qian Cai
On Wed, Jun 10, 2020 at 07:54:50AM +0200, Dmitry Vyukov wrote: > On Wed, Jun 10, 2020 at 7:22 AM Qian Cai wrote: > > > > kernel_init_free_pages() will use memset() on s390 to clear all pages > > from kmalloc_order() which will override KASAN redzones because a > > redzone was setup from the end

Re: [PATCH] mm/page_alloc: silence a KASAN false positive

2020-06-10 Thread Alexander Potapenko
On Wed, Jun 10, 2020 at 7:55 AM Dmitry Vyukov wrote: > > On Wed, Jun 10, 2020 at 7:22 AM Qian Cai wrote: > > > > kernel_init_free_pages() will use memset() on s390 to clear all pages > > from kmalloc_order() which will override KASAN redzones because a > > redzone was setup from the end of the

Re: [PATCH] mm/page_alloc: silence a KASAN false positive

2020-06-09 Thread Dmitry Vyukov
On Wed, Jun 10, 2020 at 7:22 AM Qian Cai wrote: > > kernel_init_free_pages() will use memset() on s390 to clear all pages > from kmalloc_order() which will override KASAN redzones because a > redzone was setup from the end of the allocation size to the end of the > last page. Silence it by not

[PATCH] mm/page_alloc: silence a KASAN false positive

2020-06-09 Thread Qian Cai
kernel_init_free_pages() will use memset() on s390 to clear all pages from kmalloc_order() which will override KASAN redzones because a redzone was setup from the end of the allocation size to the end of the last page. Silence it by not reporting it there. An example of the report is, BUG: