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charset="UTF-8" X-Stat-Signature: 66r4oueu8gxzwhwk7djk57w9ppdpydbp Authentication-Results: imf07.hostedemail.com; dkim=pass header.d=google.com header.s=20210112 header.b=hCoZTDIK; spf=pass (imf07.hostedemail.com: domain of dvyukov@google.com designates 209.85.161.44 as permitted sender) smtp.mailfrom=dvyukov@google.com; dmarc=pass (policy=reject) header.from=google.com X-Rspam-User: X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: C901640002 X-HE-Tag: 1651215037-932839 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Fri, 29 Apr 2022 at 08:42, syzbot wrote: > > Hello, > > syzbot found the following issue on: > > HEAD commit: 0966d385830d riscv: Fix auipc+jalr relocation range checks > git tree: git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux.git fixes > console output: https://syzkaller.appspot.com/x/log.txt?x=1128ae72f00000 > kernel config: https://syzkaller.appspot.com/x/.config?x=6295d67591064921 > dashboard link: https://syzkaller.appspot.com/bug?extid=f8181becdab66ab4b181 > compiler: riscv64-linux-gnu-gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2 > userspace arch: riscv64 > > Unfortunately, I don't have any reproducer for this issue yet. > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > Reported-by: syzbot+f8181becdab66ab4b181@syzkaller.appspotmail.com > > ============================================ > WARNING: possible recursive locking detected > 5.17.0-rc1-syzkaller-00002-g0966d385830d #0 Not tainted > -------------------------------------------- > dhcpcd-run-hook/3780 is trying to acquire lock: > ffffaf8010608d18 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_lock include/linux/mmap_lock.h:117 [inline] > ffffaf8010608d18 (&mm->mmap_lock){++++}-{3:3}, at: do_page_fault+0x24e/0xa3c arch/riscv/mm/fault.c:285 > > but task is already holding lock: > ffffaf8010608d18 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline] > ffffaf8010608d18 (&mm->mmap_lock){++++}-{3:3}, at: setup_arg_pages+0x1aa/0x4b8 fs/exec.c:793 > > other info that might help us debug this: > Possible unsafe locking scenario: > > CPU0 > ---- > lock(&mm->mmap_lock); > lock(&mm->mmap_lock); > > *** DEADLOCK *** > > May be due to missing lock nesting notation > > 1 lock held by dhcpcd-run-hook/3780: > #0: ffffaf8010608d18 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline] > #0: ffffaf8010608d18 (&mm->mmap_lock){++++}-{3:3}, at: setup_arg_pages+0x1aa/0x4b8 fs/exec.c:793 > > stack backtrace: > CPU: 1 PID: 3780 Comm: dhcpcd-run-hook Not tainted 5.17.0-rc1-syzkaller-00002-g0966d385830d #0 > Hardware name: riscv-virtio,qemu (DT) > Call Trace: > [] dump_backtrace+0x2e/0x3c arch/riscv/kernel/stacktrace.c:113 > [] show_stack+0x34/0x40 arch/riscv/kernel/stacktrace.c:119 > [] __dump_stack lib/dump_stack.c:88 [inline] > [] dump_stack_lvl+0xe4/0x150 lib/dump_stack.c:106 > [] dump_stack+0x1c/0x24 lib/dump_stack.c:113 > [] print_deadlock_bug kernel/locking/lockdep.c:2956 [inline] > [] check_deadlock kernel/locking/lockdep.c:2999 [inline] > [] validate_chain kernel/locking/lockdep.c:3788 [inline] > [] __lock_acquire+0x1dcc/0x333e kernel/locking/lockdep.c:5027 > [] lock_acquire.part.0+0x1d0/0x424 kernel/locking/lockdep.c:5639 > [] lock_acquire+0x54/0x6a kernel/locking/lockdep.c:5612 > [] down_read+0x3c/0x54 kernel/locking/rwsem.c:1461 > [] mmap_read_lock include/linux/mmap_lock.h:117 [inline] > [] do_page_fault+0x24e/0xa3c arch/riscv/mm/fault.c:285 +riscv maintainers this looks riscv related > [] ret_from_exception+0x0/0x10 > [] __stack_depot_save+0x40/0x4b2 lib/stackdepot.c:360 > > > --- > This report is generated by a bot. It may contain errors. > See https://goo.gl/tpsmEJ for more information about syzbot. > syzbot engineers can be reached at syzkaller@googlegroups.com. > > syzbot will keep track of this issue. See: > https://goo.gl/tpsmEJ#status for how to communicate with syzbot. > > -- > You received this message because you are subscribed to the Google Groups "syzkaller-bugs" group. > To unsubscribe from this group and stop receiving emails from it, send an email to syzkaller-bugs+unsubscribe@googlegroups.com. > To view this discussion on the web visit https://groups.google.com/d/msgid/syzkaller-bugs/00000000000001044205ddc55870%40google.com.