Hi all,
On a ThinkPad T430 running Linux 6.7, when I attempt to delete the ATA
device for a hard drive in the Ultrabay slot (to hotswap/undock it[1])
the process freezes in an unterruptible sleep. Specifically, if I run
echo 1 >/sys/devices/pci0000:00/0000:00:1f.2/ata2/host1/target1:0:0/1:0:0:0/delete
The shell process hangs in the write(2) syscall. The last dmesg
entries post hang are:
sd 1:0:0:0: [sda] Synchronizing SCSI cache
ata2: SATA link up 6.0 Gbps (SStatus 133 SControl 300)
ata2.00: ACPI cmd f5/00:00:00:00:00:a0(SECURITY FREEZE LOCK) filtered out
ata2.00: ACPI cmd ef/10:03:00:00:00:a0(SET FEATURES) filtered out
ata2.00: ACPI cmd f5/00:00:00:00:00:a0(SECURITY FREEZE LOCK) filtered out
ata2.00: ACPI cmd ef/10:03:00:00:00:a0(SET FEATURES) filtered out
ata2.00: configured for UDMA/133
ata2.00: retrying FLUSH 0xea Emask 0x0
On kernel versions prior to 6.5-rc1, dmesg would subsequently contain:
sd 1:0:0:0: [sda] Stopping disk
ata2.00: disable device
Note that the hang only occurs when deleting a hard disk drive. It
does not occur when deleting an optical disk drive.
I bisected the regression to 8b566edbdbfb5cde31a322c57932694ff48125ed.
I know very little about the SCSI/ATA subsystems or the internals of
ATA hotswapping/undocking. I'd appreciate any help investigating the
issue, or properly undocking.
Thanks,
Kevin
[1]: https://www.thinkwiki.org/wiki/How_to_hotswap_Ultrabay_devices
