* syzbot <syzbot+28eb226ee1d37f08087a@xxxxxxxxxxxxxxxxxxxxxxxxx> [220718 03:45]: > Hello, > > syzbot found the following issue on: > > HEAD commit: cb71b93c2dc3 Add linux-next specific files for 20220628 > git tree: linux-next > console+strace: https://syzkaller.appspot.com/x/log.txt?x=15583826080000 > kernel config: https://syzkaller.appspot.com/x/.config?x=badbc1adb2d582eb > dashboard link: https://syzkaller.appspot.com/bug?extid=28eb226ee1d37f08087a > compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2 > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=12222b9a080000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1560ab8c080000 > > The issue was bisected to: > > commit 2ee236fe53a8e2ab54679c74e8a1fb77e55b29bb > Author: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx> > Date: Tue Jun 21 20:46:53 2022 +0000 > > mm: start tracking VMAs with maple tree > > bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=10b5b252080000 > final oops: https://syzkaller.appspot.com/x/report.txt?x=12b5b252080000 > console output: https://syzkaller.appspot.com/x/log.txt?x=14b5b252080000 > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > Reported-by: syzbot+28eb226ee1d37f08087a@xxxxxxxxxxxxxxxxxxxxxxxxx > Fixes: 2ee236fe53a8 ("mm: start tracking VMAs with maple tree") > Thank you. Yes, it looks like failing the allocation after vma_adjust_trans_huge() is not working out here. What happens is a split fails to vm_adjust, so we enter the __split_vm() error code path which calls vm_ops->close(). The account for the hughtlb is actually done in the close() operation. What I can do is to avoid accounting by setting vm_start = vm_end, and vm_pgoff = 0. This way, the accounting will charge 0 as apposed to removing the vma that was never added.
