From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-oi2-f5.google.com (mail-oi2-f5.google.com [74.125.231.197]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2E5393537E0 for ; Sun, 20 Sep 2026 14:21:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=74.125.231.197 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789914094; cv=none; b=G9fxB6BZAQeXHoIiSf5y1nCfrW5LiQBrZF5tvF2vQJsx5mtc292gcDTBJTAjROBTa+rfdEgX8UrScJLdHPTLDkIX4uLsodwBODwDh0sYLj93iVqoOOgnqh21aqgt3EnA0rR9syk8cL2R1LOPEhIpzwNoyt84IGe+71q6KOEX1/I= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789914094; c=relaxed/simple; bh=Qs/AXDOMNVTVn/TaIRq5aMfQWNud2BuOIl1r8c5ZrJk=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=GBDrUDviecv1SQ55YBKkxDQ0c5wDSmDtO1cJzZM1PQBoLycqI4lN5YtF+1equNmNsu3yzbiRaq2/fwce/kMcVmBe7YZ+xRzLPmYPV1oNshhg06l9a+atSSRuXGS8MUIc0f3hxD9hUP2WwcmQic/UTGCe0+iTXtoXZGRwnTUYueg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com; arc=none smtp.client-ip=74.125.231.197 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com Received: by mail-oi2-f5.google.com with SMTP id 46e09a7af769-7f4e2118db8so1007393a34.1 for ; Sun, 20 Sep 2026 07:21:32 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20260707; t=1789914092; x=1790518892; h=content-type:to:from:subject:message-id:date:mime-version :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to :content-type; bh=SDF2KQTDPjG+jnet065vgzr3F9yXwCMJD8HQVg75NCQ=; b=npRG1AUhnw2+XPenbNIX1AWDzcjH+Fb3Cn/0rsAjxK3VZSv1ylALxQAUywposz25bU gm/8/hUAC3VR9B9s330zcsiY22vfBjLvKyT2+TYXBwgau7Bz+Jv5JCWoOI6ONKd2QMoq uilbYFK4/2LdhdwcMP0Zr9MeLmycqRaPFPDP6s23+wKAGTxwuctYBcZCUxDgvJut5obF 18nBFswAKGCLJpdNfBonZwb0riT9th3U0de7W8i4O2h68YsBuSSLCM+SflNwDW0EDp6d y1gzbY188jMjOPuHxe6Ru3c0FOSdtrRPKJaQLq57YWebYNW2lKEGR9Bfmx90AAIAn6lo sIZw== X-Gm-Message-State: AFuF++lvw0cdOAiBryeyT6NVnekv/d3LjiTH+A/ap2B+nw62mahw1Akr 6xZJsR7XwUCWLmHhKNoBIGYFu6G/9XqaTKW4gUDZ047nIsTKgjNko4T0FHToPKzs49/BEGC5BMX cl3psoJv6Qz50mwFhDR8it6f+ffDehE1DQ3CD9p/V9SP+Asc46V4qoHeovU6IXA== Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6820:1f03:b0:6b1:ba66:6998 with SMTP id 006d021491bc7-6ca9a1343a0mr7442248eaf.14.1789914092082; Sun, 20 Sep 2026 07:21:32 -0700 (PDT) Date: Sun, 20 Sep 2026 07:21:32 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <6aafebec.a6af0033.177e91.000d.GAE@google.com> Subject: [syzbot] [trace?] WARNING in check_buffer From: syzbot To: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, mathieu.desnoyers@efficios.com, mhiramat@kernel.org, rostedt@goodmis.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: 40288c9206c1 Merge tag 'drm-fixes-2026-09-19' of https://g.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=12daa525580000 kernel config: https://syzkaller.appspot.com/x/.config?x=84649d3ff8d550cb dashboard link: https://syzkaller.appspot.com/bug?extid=eb74dca0d1eb3ec227a7 compiler: gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/96e6db480769/disk-40288c92.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/d8cb5ded77e9/vmlinux-40288c92.xz kernel image: https://storage.googleapis.com/syzbot-assets/c127cac2df37/bzImage-40288c92.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+eb74dca0d1eb3ec227a7@syzkaller.appspotmail.com 0xe74: [135187] delta:1 PADDING 0xe98: [135188] delta:1 hd expected end:0xea8 last event actually ended at:0xea8 ------------[ cut here ]------------ system_state != SYSTEM_BOOTING WARNING: kernel/trace/ring_buffer.c:4783 at check_buffer.cold+0x1a2/0x1ef kernel/trace/ring_buffer.c:4783, CPU#0: syz.6.3124/18331 Modules linked in: CPU: 0 UID: 0 PID: 18331 Comm: syz.6.3124 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/05/2026 RIP: 0010:check_buffer.cold+0x1a2/0x1ef kernel/trace/ring_buffer.c:4783 Code: 03 0f b6 14 11 38 d0 7c 04 84 d2 75 5c 8b 2d 1c ce 21 10 31 ff 89 ee e8 af f2 e8 00 85 ed 0f 84 c8 8d eb 00 e8 32 f8 e8 00 90 <0f> 0b 90 e9 73 8b eb 00 49 c7 c7 c0 5e f6 8b e9 51 fe ff ff e8 88 RSP: 0018:ffffc900000078d0 EFLAGS: 00010046 RAX: 8000000001000003 RBX: 1ffff92000000f20 RCX: 0000000001000003 RDX: ffff88802d9c4b00 RSI: ffffffff8123277e RDI: ffff88802d9c4b00 RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000003 R11: 0000000000000001 R12: 0000000000021015 R13: ffff88801c095000 R14: ffff88805713c000 R15: ffffffff8bf65a60 FS: 00007ff5dabbc6c0(0000) GS:ffff888123b56000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b32508ff8 CR3: 0000000084816000 CR4: 00000000003526f0 Call Trace: __rb_reserve_next.constprop.0+0x486/0x1640 kernel/trace/ring_buffer.c:4873 rb_reserve_next_event kernel/trace/ring_buffer.c:5010 [inline] ring_buffer_lock_reserve+0x49a/0x1220 kernel/trace/ring_buffer.c:5069 __trace_buffer_lock_reserve kernel/trace/trace.h:1677 [inline] trace_event_buffer_lock_reserve+0x123/0x6f0 kernel/trace/trace.c:1924 trace_event_buffer_reserve+0x1f9/0x350 kernel/trace/trace_events.c:715 __eprobe_trace_func kernel/trace/trace_eprobe.c:443 [inline] eprobe_trigger_func+0x558/0x1450 kernel/trace/trace_eprobe.c:487 data_ops_trigger kernel/trace/trace_events_trigger.c:154 [inline] event_triggers_call+0x29e/0x4d0 kernel/trace/trace_events_trigger.c:209 __event_trigger_test_discard kernel/trace/trace.h:1738 [inline] trace_event_buffer_commit+0x66b/0xa80 kernel/trace/trace.c:2014 do_trace_event_raw_event_msr_trace_class arch/x86/include/asm/msr-trace.h:21 [inline] trace_event_raw_event_msr_trace_class+0x17d/0x270 arch/x86/include/asm/msr-trace.h:21 __do_trace_read_msr arch/x86/include/asm/msr-trace.h:40 [inline] trace_read_msr+0x160/0x1f0 arch/x86/include/asm/msr-trace.h:40 native_read_msr_safe arch/x86/include/asm/msr.h:127 [inline] rdmsrq_safe arch/x86/include/asm/msr.h:220 [inline] __rdmsr_safe_on_cpu+0xc8/0xf0 arch/x86/lib/msr-smp.c:124 csd_do_func kernel/smp.c:143 [inline] __flush_smp_call_function_queue+0x43a/0x8c0 kernel/smp.c:632 __sysvec_call_function_single+0x81/0x420 arch/x86/kernel/smp.c:272 instr_sysvec_call_function_single arch/x86/kernel/smp.c:267 [inline] sysvec_call_function_single+0x9e/0xc0 arch/x86/kernel/smp.c:267 asm_sysvec_call_function_single+0x1a/0x20 arch/x86/include/asm/idtentry.h:681 RIP: 0010:__vmcs_writel arch/x86/kvm/vmx/vmx_ops.h:224 [inline] RIP: 0010:vmcs_write32 arch/x86/kvm/vmx/vmx_ops.h:242 [inline] RIP: 0010:vmx_set_constant_host_state+0x1d4/0x740 arch/x86/kvm/vmx/vmx.c:4498 Code: e8 71 ed 6b 00 b9 74 01 00 00 0f 32 48 c1 e2 20 48 89 d3 48 09 c3 e9 ba 01 00 00 e8 56 ed 6b 00 89 db b8 00 4c 00 00 0f 79 c3 <0f> 86 f5 01 00 00 e8 41 ed 6b 00 b9 76 01 00 00 0f 32 48 c1 e2 20 RSP: 0018:ffffc90003d97828 EFLAGS: 00000202 RAX: 0000000000004c00 RBX: 0000000000000010 RCX: ffffc9000ebc9000 RDX: 0000000000080000 RSI: ffffffff81a0325a RDI: ffff88802d9c4b00 RBP: 00000000003526f0 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffff88807e391f78 R13: ffff88807e391ed8 R14: ffff888051ff8000 R15: ffff88807e391f78 init_vmcs arch/x86/kvm/vmx/vmx.c:4946 [inline] __vmx_vcpu_reset arch/x86/kvm/vmx/vmx.c:5014 [inline] vmx_vcpu_reset+0x117b/0x3160 arch/x86/kvm/vmx/vmx.c:5047 kvm_vcpu_reset+0x9d1/0x1ae0 arch/x86/kvm/x86.c:9615 kvm_arch_vcpu_create+0x70c/0xab0 arch/x86/kvm/x86.c:9415 kvm_vm_ioctl_create_vcpu virt/kvm/kvm_main.c:4213 [inline] kvm_vm_ioctl+0x7e3/0x42d0 virt/kvm/kvm_main.c:5178 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl fs/ioctl.c:583 [inline] __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7ff5d9d9e159 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ff5dabbc028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007ff5da026090 RCX: 00007ff5d9d9e159 RDX: 0000000000000000 RSI: 000000000000ae41 RDI: 0000000000000005 RBP: 00007ff5d9e3506b R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ff5da026128 R14: 00007ff5da026090 R15: 00007fff730b6718 ---------------- Code disassembly (best guess): 0: e8 71 ed 6b 00 call 0x6bed76 5: b9 74 01 00 00 mov $0x174,%ecx a: 0f 32 rdmsr c: 48 c1 e2 20 shl $0x20,%rdx 10: 48 89 d3 mov %rdx,%rbx 13: 48 09 c3 or %rax,%rbx 16: e9 ba 01 00 00 jmp 0x1d5 1b: e8 56 ed 6b 00 call 0x6bed76 20: 89 db mov %ebx,%ebx 22: b8 00 4c 00 00 mov $0x4c00,%eax 27: 0f 79 c3 vmwrite %rbx,%rax * 2a: 0f 86 f5 01 00 00 jbe 0x225 <-- trapping instruction 30: e8 41 ed 6b 00 call 0x6bed76 35: b9 76 01 00 00 mov $0x176,%ecx 3a: 0f 32 rdmsr 3c: 48 c1 e2 20 shl $0x20,%rdx --- This report is generated by a bot. 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