From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 3F0847494 for ; Fri, 7 Nov 2025 08:10:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762503020; cv=none; b=TZtGsLdE4xIt5vKrNuZd3MEkVhmLHrnSN758o3/nHa8HX1/4de570dyR8PMC9eh8eOsn7czaBlSqgAsXvkJZOsxnaTFv6yex/vgPFJeCHerjHsmksE2Z2D0p2E8EeS2zZNUXSA/+zdd2Qw/pLoRIr36zKT0W0nTYahLwR3+byms= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762503020; c=relaxed/simple; bh=JH6EpzHDDOKZ9X/qUeOGLrVUFHrWbP6JeOabD/0ZuYg=; h=From:To:Subject:Date:Message-ID:Content-Type:MIME-Version; b=UhZFDiwm/Tka2orBewueIG/6MpLRv/VUyj1sXrf52VLi6Mt+yTOBnrG+HTxpFQVP3Aueo4LL44qwSOgeEt0n8lkHgcUPvxfoaTAwve8Kqm0wF2rEcFqyNf4sNn2TTxjmLiiJYW55xDZep5MlQFc1ji5XhXhQ89vzaOG5ORoYzfk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=rCcXqWhH; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="rCcXqWhH" Received: by smtp.kernel.org (Postfix) with ESMTPS id D1ADCC116C6 for ; Fri, 7 Nov 2025 08:10:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1762503019; bh=JH6EpzHDDOKZ9X/qUeOGLrVUFHrWbP6JeOabD/0ZuYg=; h=From:To:Subject:Date:From; b=rCcXqWhH/b6c9f5KYIOTHBJ594Kk6elORCj9rTdDdWwzy5x0l2631kXkgRVNdncaI hc5lQH+0TbZDAm1EJk1sMpVnuwGRNiWK6mZ9PvInRC5x1Q6gcXr5rz6uzHhECqAdkN 8buNFaVfbNMx07GWCdCubxRqj4lhZQ/rb4PETyouNzlkXhNYe0h0y8eoyWGxJuiNBj OyiyfAbokqG2+rSEZF/ZI3eEjm3w21g2yapiKFtaacJV85eLA18UXeaQtB75raRryD mkDP0obsepoI20AjKqL+SnX+ZswPHlRWCL5UKWhZSptGjNGYQANlEaDbbWRZJjzGe3 ElNwJJw2u93nw== Received: by aws-us-west-2-korg-bugzilla-1.web.codeaurora.org (Postfix, from userid 48) id B48BEC53BC9; Fri, 7 Nov 2025 08:10:19 +0000 (UTC) From: bugzilla-daemon@kernel.org To: linux-ext4@vger.kernel.org Subject: [Bug 220760] New: Observed data-race in _find_next_bit+0x42/0xf0 Date: Fri, 07 Nov 2025 08:10:19 +0000 X-Bugzilla-Reason: None X-Bugzilla-Type: new X-Bugzilla-Watch-Reason: AssignedTo fs_ext4@kernel-bugs.osdl.org X-Bugzilla-Product: File System X-Bugzilla-Component: ext4 X-Bugzilla-Version: 2.5 X-Bugzilla-Keywords: X-Bugzilla-Severity: high X-Bugzilla-Who: parsishashank351@gmail.com X-Bugzilla-Status: NEW X-Bugzilla-Resolution: X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: fs_ext4@kernel-bugs.osdl.org X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: bug_id short_desc product version rep_platform op_sys bug_status bug_severity priority component assigned_to reporter cf_regression attachments.created Message-ID: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: https://bugzilla.kernel.org/ Auto-Submitted: auto-generated Precedence: bulk X-Mailing-List: linux-ext4@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 https://bugzilla.kernel.org/show_bug.cgi?id=3D220760 Bug ID: 220760 Summary: Observed data-race in _find_next_bit+0x42/0xf0 Product: File System Version: 2.5 Hardware: AMD OS: Linux Status: NEW Severity: high Priority: P3 Component: ext4 Assignee: fs_ext4@kernel-bugs.osdl.org Reporter: parsishashank351@gmail.com Regression: No Created attachment 308913 --> https://bugzilla.kernel.org/attachment.cgi?id=3D308913&action=3Dedit _find_next_bit+0x42/0xf0 Hello Team, i have build linux kernel 6.17.7 by taking code from kernel.org and i have enabled CONFIG_KCSAN in kernel config file and installed the kernel. After the initial boot, i saw some concurrency issues in dmesg kernel ring buffer. Few are related to ACPI and few are related to timer subsystem. ref dmesg log: [ 356.704237] BUG: KCSAN: data-race in _find_next_bit+0x42/0xf0 [ 356.704264] race at unknown origin, with read to 0xffff88a9c0004230 of 8 bytes by interrupt on cpu 0: [ 356.704279] _find_next_bit+0x42/0xf0 [ 356.704297] _nohz_idle_balance.isra.0+0x219/0x3a0 [ 356.704317] sched_balance_softirq+0x73/0x90 [ 356.704335] handle_softirqs+0xd8/0x310 [ 356.704358] __irq_exit_rcu+0x11a/0x140 [ 356.704377] irq_exit_rcu+0xe/0x20 [ 356.704396] sysvec_call_function_single+0x96/0xb0 [ 356.704421] asm_sysvec_call_function_single+0x1b/0x20 [ 356.704440] pv_native_safe_halt+0xb/0x10 [ 356.704454] arch_cpu_idle+0x9/0x10 [ 356.704471] default_idle_call+0x30/0x110 [ 356.704489] do_idle+0x203/0x240 [ 356.704505] cpu_startup_entry+0x2c/0x30 [ 356.704520] rest_init+0x121/0x140 [ 356.704536] start_kernel+0x9ed/0xe60 [ 356.704559] x86_64_start_reservations+0x18/0x30 [ 356.704579] x86_64_start_kernel+0xfe/0x150 [ 356.704596] common_startup_64+0x13e/0x141 [ 356.704627] value changed: 0x000000009ffdfbfd -> 0x000000009ffdebfd [ 356.704645] Reported by Kernel Concurrency Sanitizer on: [ 356.704658] CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.17.7 #4 PREEMPT(voluntary) [ 356.704678] Hardware name: VMware, Inc. VMware20,1/440BX Desktop Referen= ce Platform, BIOS VMW201.00V.23553139.B64.2403260940 03/26/2024 [ 356.704690] =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D [ 356.705780] scsi host28: ahci [ 356.707193] scsi host29: ahci [ 356.708567] scsi host30: ahci [ 356.709878] scsi host31: ahci [ 356.711303] scsi host32: ahci [ 356.712465] ata3: SATA max UDMA/133 abar m4096@0xfe210000 port 0xfe210100 irq 34 lpm-pol 1 ext [ 356.712481] ata4: SATA max UDMA/133 abar m4096@0xfe210000 port 0xfe210180 irq 34 lpm-pol 1 ext [ 356.712531] ata5: SATA max UDMA/133 abar m4096@0xfe210000 port 0xfe210200 irq 34 lpm-pol 1 ext [ 356.712545] ata6: SATA max UDMA/133 abar m4096@0xfe210000 port 0xfe210280 irq 34 lpm-pol 1 ext [ 356.712559] ata7: SATA max UDMA/133 abar m4096@0xfe210000 port 0xfe210300 irq 34 lpm-pol 1 ext [ 356.712572] ata8: SATA max UDMA/133 abar m4096@0xfe210000 port 0xfe210380 irq 34 lpm-pol 1 ext [ 356.712596] ata9: SATA max UDMA/133 abar m4096@0xfe210000 port 0xfe210400 irq 34 lpm-pol 1 ext [ 356.712674] ata10: SATA max UDMA/133 abar m4096@0xfe210000 port 0xfe2104= 80 irq 34 lpm-pol 1 ext [ 356.712687] ata11: SATA max UDMA/133 abar m4096@0xfe210000 port 0xfe2105= 00 irq 34 lpm-pol 1 ext [ 356.712701] ata12: SATA max UDMA/133 abar m4096@0xfe210000 port 0xfe2105= 80 irq 34 lpm-pol 1 ext [ 356.712770] ata13: SATA max UDMA/133 abar m4096@0xfe210000 port 0xfe2106= 00 irq 34 lpm-pol 1 ext [ 356.712784] ata14: SATA max UDMA/133 abar m4096@0xfe210000 port 0xfe2106= 80 irq 34 lpm-pol 1 ext [ 356.712798] ata15: SATA max UDMA/133 abar m4096@0xfe210000 port 0xfe2107= 00 irq 34 lpm-pol 1 ext [ 356.712812] ata16: SATA max UDMA/133 abar m4096@0xfe210000 port 0xfe2107= 80 irq 34 lpm-pol 1 ext [ 356.712826] ata17: SATA max UDMA/133 abar m4096@0xfe210000 port 0xfe2108= 00 irq 34 lpm-pol 1 ext [ 356.712840] ata18: SATA max UDMA/133 abar m4096@0xfe210000 port 0xfe2108= 80 irq 34 lpm-pol 1 ext [ 356.712914] ata19: SATA max UDMA/133 abar m4096@0xfe210000 port 0xfe2109= 00 irq 34 lpm-pol 1 ext [ 356.712928] ata20: SATA max UDMA/133 abar m4096@0xfe210000 port 0xfe2109= 80 irq 34 lpm-pol 1 ext [ 356.712942] ata21: SATA max UDMA/133 abar m4096@0xfe210000 port 0xfe210a= 00 irq 34 lpm-pol 1 ext [ 356.712955] ata22: SATA max UDMA/133 abar m4096@0xfe210000 port 0xfe210a= 80 irq 34 lpm-pol 1 ext [ 356.712968] ata23: SATA max UDMA/133 abar m4096@0xfe210000 port 0xfe210b= 00 irq 34 lpm-pol 1 ext [ 356.713031] ata24: SATA max UDMA/133 abar m4096@0xfe210000 port 0xfe210b= 80 irq 34 lpm-pol 1 ext [ 356.713044] ata25: SATA max UDMA/133 abar m4096@0xfe210000 port 0xfe210c= 00 irq 34 lpm-pol 1 ext [ 356.713057] ata26: SATA max UDMA/133 abar m4096@0xfe210000 port 0xfe210c= 80 irq 34 lpm-pol 1 ext [ 356.713072] ata27: SATA max UDMA/133 abar m4096@0xfe210000 port 0xfe210d= 00 irq 34 lpm-pol 1 ext [ 356.713125] ata28: SATA max UDMA/133 abar m4096@0xfe210000 port 0xfe210d= 80 irq 34 lpm-pol 1 ext [ 356.713138] ata29: SATA max UDMA/133 abar m4096@0xfe210000 port 0xfe210e= 00 irq 34 lpm-pol 1 ext [ 356.713164] ata30: SATA max UDMA/133 abar m4096@0xfe210000 port 0xfe210e= 80 irq 34 lpm-pol 1 ext [ 356.713240] ata31: SATA max UDMA/133 abar m4096@0xfe210000 port 0xfe210f= 00 irq 34 lpm-pol 1 ext [ 356.713253] ata32: SATA max UDMA/133 abar m4096@0xfe210000 port 0xfe210f= 80 irq 34 lpm-pol 1 ext [ 356.738288] usbcore: registered new interface driver usbhid [ 356.738300] usbhid: USB HID core driver [ 357.022742] ata27: SATA link down (SStatus 0 SControl 300) [ 357.022941] ata25: SATA link down (SStatus 0 SControl 300) [ 357.023093] ata22: SATA link down (SStatus 0 SControl 300) [ 357.023241] ata31: SATA link down (SStatus 0 SControl 300) [ 357.023373] ata13: SATA link down (SStatus 0 SControl 300) [ 357.023490] ata24: SATA link down (SStatus 0 SControl 300) [ 357.023618] ata20: SATA link down (SStatus 0 SControl 300) [ 357.023763] ata7: SATA link down (SStatus 0 SControl 300) [ 357.023994] ata18: SATA link down (SStatus 0 SControl 300) [ 357.024218] ata32: SATA link down (SStatus 0 SControl 300) [ 357.024352] ata19: SATA link down (SStatus 0 SControl 300) [ 357.024499] ata9: SATA link down (SStatus 0 SControl 300) [ 357.024712] ata6: SATA link down (SStatus 0 SControl 300) [ 357.024901] ata26: SATA link down (SStatus 0 SControl 300) [ 357.025010] ata12: SATA link down (SStatus 0 SControl 300) [ 357.025116] ata30: SATA link down (SStatus 0 SControl 300) [ 357.025308] ata17: SATA link down (SStatus 0 SControl 300) [ 357.025426] ata28: SATA link down (SStatus 0 SControl 300) [ 357.025544] ata4: SATA link down (SStatus 0 SControl 300) [ 357.025630] ata23: SATA link down (SStatus 0 SControl 300) [ 357.025760] ata3: SATA link up 6.0 Gbps (SStatus 133 SControl 300) [ 357.025908] ata15: SATA link down (SStatus 0 SControl 300) [ 357.026035] ata16: SATA link down (SStatus 0 SControl 300) [ 357.026210] ata29: SATA link down (SStatus 0 SControl 300) [ 357.026322] ata21: SATA link down (SStatus 0 SControl 300) [ 357.026432] ata10: SATA link down (SStatus 0 SControl 300) [ 357.026631] ata5: SATA link down (SStatus 0 SControl 300) [ 357.026733] ata11: SATA link down (SStatus 0 SControl 300) [ 357.026848] ata8: SATA link down (SStatus 0 SControl 300) [ 357.027037] ata14: SATA link down (SStatus 0 SControl 300) [ 357.027222] ata3.00: ATAPI: VMware Virtual SATA CDRW Drive, 00000001, max UDMA/33 [ 357.027523] ata3.00: configured for UDMA/33 [ 357.028728] scsi 3:0:0:0: CD-ROM NECVMWar VMware SATA CD00 1.= 00 PQ: 0 ANSI: 5 [ 357.030610] sr 3:0:0:0: [sr0] scsi3-mmc drive: 1x/1x writer dvd-ram cd/rw xa/form2 cdda tray [ 357.030693] cdrom: Uniform CD-ROM driver Revision: 3.20 [ 357.071982] sr 3:0:0:0: Attached scsi CD-ROM sr0 [ 357.072960] sr 3:0:0:0: Attached scsi generic sg1 type 5 [ 357.098035] input: VMware VMware Virtual USB Mouse as /devices/pci0000:02/0000:02:01.0/usb1/1-1/1-1:1.0/0003:0E0F:0003.0001/input= /input5 [ 357.099472] hid-generic 0003:0E0F:0003.0001: input,hidraw0: USB HID v1.10 Mouse [VMware VMware Virtual USB Mouse] on usb-0000:02:01.0-1/input0 [ 357.398735] fbcon: Taking over console [ 357.402271] Console: switching to colour frame buffer device 128x48 [ 357.549114] EXT4-fs (sda4): mounted filesystem 574a78d5-a611-492b-a2fd-0fd9308f950d ro with ordered data mode. Quota mode: none. [ 363.330092] systemd[1]: Inserted module 'autofs4' [ 363.381819] systemd[1]: systemd 249.11-0ubuntu3.16 running in system mode (+PAM +AUDIT +SELINUX +APPARMOR +IMA +SMACK +SECCOMP +GCRYPT +GNUTLS +OPENS= SL +ACL +BLKID +CURL +ELFUTILS +FIDO2 +IDN2 -IDN +IPTC +KMOD +LIBCRYPTSETUP +LIBFDISK +PCRE2 -PWQUALITY -P11KIT -QRENCODE +BZIP2 +LZ4 +XZ +ZLIB +ZSTD -XKBCOMMON +UTMP +SYSVINIT default-hierarchy=3Dunified) [ 363.382132] systemd[1]: Detected virtualization vmware. [ 363.382510] systemd[1]: Detected architecture x86-64. --=20 You may reply to this email to add a comment. You are receiving this mail because: You are watching the assignee of the bug.=