From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C249230C160 for ; Fri, 4 Sep 2026 05:40:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788500447; cv=none; b=V5FjaTs931gimcBDX7p3TTboGir9wvkZn3DS+Lj4Nx5gaRr7uz1g4mij9CYoVqouI+WyH0CWsMZRdudPi0UMfuWt3Ugh1Lyjxxec6/fVx7DgxWinEEvmZBp4VrVY73qkZNt5f/x4pz5c4dAxq5MwPzUndo84D1uHOd7uZZUwpUc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788500447; c=relaxed/simple; bh=oBkZqD8z7VEeSY4eMxro8rmnifQulYHdec6qnb762zw=; h=From:To:Cc:Subject:In-Reply-To:References:Date:Message-ID: MIME-Version:Content-Type; b=qNa4eNba7s2IY0/9eVsX2Zmbdm/byvoy84nPTwWIs3k5Eg5Yuz1S8Lvar7UXFGH7j8WhGSaAmttt55RYHOy01G3ktZSjnQWAakK2P7C0jtQuyjeL4aCDyF3bDij1jbCtB3Yxahgbhc5MwfiU3NJDrcGFzcs3BJPOgx2H/YfZiN0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Y4Nt/Xbg; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Y4Nt/Xbg" Received: by smtp.kernel.org (Postfix) with ESMTPSA id EF3201F00A3E; Fri, 4 Sep 2026 05:40:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1788500445; bh=BlKzeHDQmdtQhSMD7OZocK5DgYOQx2sPWKFRmowF4ZA=; h=From:To:Cc:Subject:In-Reply-To:References:Date; b=Y4Nt/XbgyI8nVqTwDtBy/J2KzyHS2HOTvEw+ONB+x+Qe4BI+8XA29uFRrhjEiXBsS nVoEeo8qQnWTyzKYycrZ/OChUZQEOWR8CU+P3Gg9CzxqXrOKgPVPKPHgNNNKgb8M+X rYToNvecMtejJkCQaOZ7vNiJfOQ5oOt1hGG+AifQhnhFKmTD0ZdDpDu92fZ42o/yWh EVjeWIGWG14do/+Ftly9yAA7Rlcg92BEit6NpzuUjrenoedMdR8/WZVw75toIy8IML VVyjnWo0Xm3zMAleaV4FwUkxEhss7K/SGb3TFqXST0JQsTsFLtAGEaWQWizR3h9WvV h9vB5Jffv81fA== From: Thomas Gleixner To: syzbot , andrealmeid@igalia.com, dave@stgolabs.net, dvhart@infradead.org, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, syzkaller-bugs@googlegroups.com Cc: Catalin Marinas , Will Deacon , Mark Rutland Subject: Re: [syzbot] [kernel?] Internal error in futex_wake_op In-Reply-To: <6a908778.1d9ded08.62e62.00dc.GAE@google.com> References: <6a908778.1d9ded08.62e62.00dc.GAE@google.com> Date: Fri, 04 Sep 2026 07:40:42 +0200 Message-ID: <877bl1a811.ffs@fw13> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain On Thu, Aug 27 2026 at 11:52, syzbot wrote: CC+: ARM64 people... > Hello, > > syzbot found the following issue on: > > HEAD commit: 68f892e99df9 Merge branch 'for-next/core' into for-kernelci > git tree: git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci > console output: https://syzkaller.appspot.com/x/log.txt?x=13dc7415580000 > kernel config: https://syzkaller.appspot.com/x/.config?x=d1128bc53f2ef7f3 > dashboard link: https://syzkaller.appspot.com/bug?extid=417a6b7c02d5d03f9aa6 > compiler: Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8 > userspace arch: arm64 > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1512d625580000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=13e2859e580000 > > Downloadable assets: > disk image: https://storage.googleapis.com/syzbot-assets/f98dd20a7b98/disk-68f892e9.raw.xz > vmlinux: https://storage.googleapis.com/syzbot-assets/441f1ad32549/vmlinux-68f892e9.xz > kernel image: https://storage.googleapis.com/syzbot-assets/8da5227b7dc8/Image-68f892e9.gz.xz > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > Reported-by: syzbot+417a6b7c02d5d03f9aa6@syzkaller.appspotmail.com > > futex_wake_op: syz.0.17 tries to shift op by 144; fix this program > Internal error: synchronous external abort: 0000000096000010 [#1] SMP > Modules linked in: > CPU: 0 UID: 0 PID: 4917 Comm: syz.0.17 Tainted: G M syzkaller #0 PREEMPT > Tainted: [M]=MACHINE_CHECK > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/07/2026 > pstate: 83000005 (Nzcv daif -PAN -UAO +TCO +DIT -SSBS BTYPE=--) > pc : __llsc_futex_atomic_or arch/arm64/include/asm/futex.h:51 [inline] > pc : __futex_atomic_or arch/arm64/include/asm/futex.h:239 [inline] > pc : arch_futex_atomic_op_inuser arch/arm64/include/asm/futex.h:269 [inline] > pc : futex_atomic_op_inuser kernel/futex/waitwake.c:251 [inline] > pc : futex_wake_op+0x450/0xfe8 kernel/futex/waitwake.c:302 > lr : mte_enable_tco arch/arm64/include/asm/mte-kasan.h:62 [inline] > lr : uaccess_enable_privileged arch/arm64/include/asm/uaccess.h:147 [inline] > lr : __llsc_futex_atomic_or arch/arm64/include/asm/futex.h:51 [inline] > lr : __futex_atomic_or arch/arm64/include/asm/futex.h:239 [inline] > lr : arch_futex_atomic_op_inuser arch/arm64/include/asm/futex.h:269 [inline] > lr : futex_atomic_op_inuser kernel/futex/waitwake.c:251 [inline] > lr : futex_wake_op+0x43c/0xfe8 kernel/futex/waitwake.c:302 > sp : ffff800093197980 > x29: ffff800093197b40 x28: 0000000000010000 x27: 0000000000000000 > x26: 1fffe00018d2a3ad x25: dfff800000000000 x24: ffff0000c6951d40 > x23: ffff0000c6951d6c x22: 0000000000000002 x21: 1fffe00018d2a685 > x20: ffff0000c1df3780 x19: ffff0000c695342c x18: 0000000000000000 > x17: 72676f7270207369 x16: 687420786966203b x15: 3434312079622070 > x14: 6f20746669687320 x13: 0000000000000001 x12: 0000000000000000 > x11: 0000000000000000 x10: 00000000fffffff5 x9 : 0000000000000000 > x8 : 0000000000000080 x7 : ffff80008048c60c x6 : 0000000000000000 > x5 : 0000000000000000 x4 : 0000000000000000 x3 : ffff8000805b0678 > x2 : 0000000000000002 x1 : ffff0000c6951d40 x0 : 0000000000000000 > Call trace: > __llsc_futex_atomic_or arch/arm64/include/asm/futex.h:51 [inline] (P) > __futex_atomic_or arch/arm64/include/asm/futex.h:239 [inline] (P) > arch_futex_atomic_op_inuser arch/arm64/include/asm/futex.h:269 [inline] (P) > futex_atomic_op_inuser kernel/futex/waitwake.c:251 [inline] (P) > futex_wake_op+0x450/0xfe8 kernel/futex/waitwake.c:302 (P) > do_futex+0x200/0x378 kernel/futex/syscalls.c:144 > __do_sys_futex kernel/futex/syscalls.c:210 [inline] > __se_sys_futex kernel/futex/syscalls.c:191 [inline] > __arm64_sys_futex+0x2e4/0x418 kernel/futex/syscalls.c:191 > __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] > invoke_syscall+0x98/0x244 arch/arm64/kernel/syscall.c:49 > el0_svc_common+0xec/0x23c arch/arm64/kernel/syscall.c:121 > do_el0_svc+0x4c/0x5c arch/arm64/kernel/syscall.c:140 > el0_svc+0x64/0x260 arch/arm64/kernel/entry-common.c:758 > el0t_64_sync_handler+0x44/0x104 arch/arm64/kernel/entry-common.c:777 > el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:590 > Code: d500409f 1280014a f94057eb f9800171 (885f7d76) > ---[ end trace 0000000000000000 ]--- > ---------------- > Code disassembly (best guess): > 0: d500409f msr pan, #0x0 > 4: 1280014a mov w10, #0xfffffff5 // #-11 > 8: f94057eb ldr x11, [sp, #168] > c: f9800171 prfm pstl1strm, [x11] > * 10: 885f7d76 ldxr w22, [x11] <-- trapping instruction > > > --- > 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. > > If the report is already addressed, let syzbot know by replying with: > #syz fix: exact-commit-title > > If you want syzbot to run the reproducer, reply with: > #syz test: git://repo/address.git branch-or-commit-hash > If you attach or paste a git patch, syzbot will apply it before testing. > > If you want to overwrite report's subsystems, reply with: > #syz set subsystems: new-subsystem > (See the list of subsystem names on the web dashboard) > > If the report is a duplicate of another one, reply with: > #syz dup: exact-subject-of-another-report > > If you want to undo deduplication, reply with: > #syz undup