Noticed the same here when upgrading from 6.1.0-13-amd64 to 6.5.0-0.deb12.1-amd64 (both Debian kernels) earlier this month: ============================================================================ $ sar -f /var/log/sysstat/sa20231108 CPU %user %nice %system %iowait %steal %idle [...] 18:30:03 all 1.03 0.00 0.45 0.04 0.00 98.47 18:40:01 all 1.07 0.00 0.52 0.05 0.00 98.36 18:50:01 all 1.07 0.00 0.53 0.04 0.00 98.37 19:00:01 all 1.35 0.00 0.69 0.08 0.00 97.88 19:10:04 all 1.09 0.00 0.52 0.07 0.00 98.31 19:20:02 all 1.14 0.00 0.51 0.05 0.00 98.30 19:30:04 all 1.62 0.00 0.65 0.08 0.00 97.65 Average: all 1.06 0.00 0.50 0.06 0.00 98.38 19:32:27 LINUX RESTART (2 CPU) 19:40:03 CPU %user %nice %system %iowait %steal %idle 19:50:00 all 2.27 0.00 3.23 57.40 0.00 37.11 20:00:02 all 1.29 0.00 2.70 59.27 0.00 36.75 20:10:03 all 1.48 0.00 2.93 58.38 0.00 37.21 20:20:03 all 1.40 0.00 2.94 58.93 0.00 36.73 20:30:02 all 1.39 0.00 2.87 59.99 0.00 35.74 20:40:03 all 1.48 0.00 3.44 59.83 0.00 35.26 20:50:00 all 1.29 0.00 2.88 60.84 0.00 34.98 21:00:03 all 1.31 0.00 2.63 59.81 0.00 36.25 21:10:03 all 1.33 0.00 2.72 59.85 0.00 36.09 21:20:01 all 1.31 0.00 2.82 59.28 0.00 36.59 21:30:01 all 1.39 0.00 2.92 60.51 0.00 35.18 21:40:01 all 1.34 0.00 3.04 60.04 0.00 35.57 21:50:03 all 1.29 0.00 2.51 59.79 0.00 36.41 22:00:03 all 1.36 0.00 3.23 59.81 0.00 35.59 22:10:03 all 1.37 0.00 2.56 59.13 0.00 36.93 22:20:03 all 1.36 0.00 2.88 58.46 0.00 37.29 22:30:03 all 1.31 0.00 2.65 59.07 0.00 36.97 22:40:00 all 1.32 0.00 2.72 59.61 0.00 36.35 22:50:01 all 1.32 0.00 2.72 59.35 0.00 36.61 23:00:03 all 1.29 0.00 2.68 59.30 0.00 36.72 23:10:03 all 1.35 0.00 2.62 60.11 0.00 35.91 23:20:02 all 1.29 0.00 2.91 59.55 0.00 36.25 23:30:03 all 1.32 0.00 2.72 58.37 0.00 37.59 23:40:01 all 1.34 0.00 2.97 57.74 0.00 37.95 23:50:00 all 1.33 0.00 2.54 59.90 0.00 36.24 Average: all 1.38 0.00 2.83 59.37 0.00 36.41 $ last -n 3 reboot reboot system boot 6.5.0-0.deb12.1- Wed Nov 8 19:32 still running reboot system boot 6.1.0-13-amd64 Mon Oct 9 23:14 - 19:32 (29+21:17) reboot system boot 6.1.0-13-amd64 Mon Oct 9 22:39 - 23:14 (00:35) ============================================================================ And top only shows a single [scsi_eh_2] thread using ~50% of CPU time, sometimes there's an events thread too. PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 336 root 20 0 0.0m 0.0m 0.0m D 50.0 0.0 53,37 [scsi_eh_2] 3794126 root 20 0 0.0m 0.0m 0.0m I 25.7 0.0 0:06.27 [kworker/0:0-events] This is a Debian/amd64 VM running on a VMware ESX host. There's a virtual CDROM drive, but nothing is attached here and I'm not using it, all: ============================================================================ $ lsblk -d --scsi NAME HCTL TYPE VENDOR MODEL REV SERIAL TRAN sda 0:0:0:0 disk VMware Virtual disk 2.0 sr0 2:0:0:0 rom NECVMWar VMware Virtual IDE CDROM Drive 1.00 10000000000000000001 ata $ dmesg -t | grep -i scsi Block layer SCSI generic (bsg) driver version 0.4 loaded (major 247) SCSI subsystem initialized VMware PVSCSI driver - version 1.0.7.0-k vmw_pvscsi: using 64bit dma vmw_pvscsi: max_id: 65 vmw_pvscsi: setting ring_pages to 32 vmw_pvscsi: enabling reqCallThreshold vmw_pvscsi: driver-based request coalescing enabled vmw_pvscsi: using MSI-X scsi host0: VMware PVSCSI storage adapter rev 2, req/cmp/msg rings: 32/32/1 pages, cmd_per_lun=254 vmw_pvscsi 0000:03:00.0: VMware PVSCSI rev 2 host #0 scsi 0:0:0:0: Direct-Access VMware Virtual disk 2.0 PQ: 0 ANSI: 6 sd 0:0:0:0: [sda] Attached SCSI disk sd 0:0:0:0: Attached scsi generic sg0 type 0 scsi host1: ata_piix scsi host2: ata_piix scsi 2:0:0:0: CD-ROM NECVMWar VMware IDE CDR10 1.00 PQ: 0 ANSI: 5 scsi 2:0:0:0: Attached scsi generic sg1 type 5 sr 2:0:0:0: [sr0] scsi3-mmc drive: 1x/1x writer dvd-ram cd/rw xa/form2 cdda tray sr 2:0:0:0: Attached scsi CD-ROM sr0 ============================================================================ Will that "scsi: Do no try to probe for CDL on old drives" patch land in mainline or is this still under discussion?