On Sat, 14 Aug 2021 04:07:23 -0700 syzbot <syzbot+57876cfc2dca0c6b2e6a@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote: > Hello, > > syzbot found the following issue on: Thanks. > HEAD commit: 92d00774360d Add linux-next specific files for 20210810 > git tree: linux-next > console output: https://syzkaller.appspot.com/x/log.txt?x=12e2b4d9300000 > kernel config: https://syzkaller.appspot.com/x/.config?x=a6933fa6f9a86ca9 > dashboard link: https://syzkaller.appspot.com/bug?extid=57876cfc2dca0c6b2e6a > compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.1 > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=16f81581300000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=11419dfa300000 > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > Reported-by: syzbot+57876cfc2dca0c6b2e6a@xxxxxxxxxxxxxxxxxxxxxxxxx > > BUG: unable to handle page fault for address: fffffffffffffffc > #PF: supervisor write access in kernel mode > #PF: error_code(0x0002) - not-present page > PGD b68f067 P4D b68f067 PUD b691067 PMD 0 > Oops: 0002 [#1] PREEMPT SMP KASAN > CPU: 0 PID: 6601 Comm: syz-executor361 Not tainted 5.14.0-rc5-next-20210810-syzkaller #0 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 > RIP: 0010:__list_add include/linux/list.h:71 [inline] > RIP: 0010:list_add include/linux/list.h:86 [inline] > RIP: 0010:alloc_huge_page+0xdcb/0x11b0 mm/hugetlb.c:2821 That appears to be list_add(&page->lru, &h->hugepage_activelist); I'm suspecting Mike's surplus page changes? > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=11419dfa300000 Nice to have that,
