Difference between revisions of "Problems with SATA and Linux"

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Linux kernels (as of 2.6.15-rc3) do not support suspend and resume for SATA devices. As a result, the machine hangs upon the first disk access after resume. A kernel patch ([http://lkml.org/lkml/2005/5/2/46 LKML posting]) fixes this by adding SATA power management support.
 
Linux kernels (as of 2.6.15-rc3) do not support suspend and resume for SATA devices. As a result, the machine hangs upon the first disk access after resume. A kernel patch ([http://lkml.org/lkml/2005/5/2/46 LKML posting]) fixes this by adding SATA power management support.
  
Current release-candidates for 2.6.16 ([http://www.kernel.org/pub/linux/kernel/v2.6/testing/ChangeLog-2.6.16-rc1 Changelog for 2.6.16-rc1]) have the patch already included], so no more patching will be necessary with 2.6.16. In fact, the 2.6.15.1 release has the patch included.
+
Current release-candidates for 2.6.16 ([http://www.kernel.org/pub/linux/kernel/v2.6/testing/ChangeLog-2.6.16-rc1 Changelog for 2.6.16-rc1]) have the patch already included], so no more patching will be necessary with 2.6.16.
  
 
===Patches===
 
===Patches===

Revision as of 18:21, 17 January 2006

Some ThinkPad models use a SATA controller for the system hard disk. This causes several complications for Linux installation. The following lists these problems and known workarounds. Note that the details are often version- and distribution-specific.

Models using a SATA disk interface

Models using a SATA controller and a SATA system disk:

Models using a SATA controller and a PATA (IDE) system disk with a SATA-to-PATA bridge:

NOTE!
Some of these problems (namely SMART support, power management and disk information) are solved in Linux 2.6.15 with the inclusion of libata pass-through. See the SATA driver features, software status and hardware status.

Hang on resume from suspend to RAM

Linux kernels (as of 2.6.15-rc3) do not support suspend and resume for SATA devices. As a result, the machine hangs upon the first disk access after resume. A kernel patch (LKML posting) fixes this by adding SATA power management support.

Current release-candidates for 2.6.16 (Changelog for 2.6.16-rc1) have the patch already included], so no more patching will be necessary with 2.6.16.

Patches

Some distributions already include this patch (e.g., Ubuntu Breezy), but some don't (e.g., Fedora 4).

Links

Failed resume from suspend to disk

Suspend to disk (using swsusp or Software Suspend 2) needs to load the memory image from the SATA disk. For this to work, you either need an initrd with all the necessary SATA modules, or the SATA drivers compiled into the kernel.

DVD drive not recognized

The ata_piix SATA driver grabs ownership over the IDE ports when it is loaded, but (by default) does not support PATA ATAPI devices such as the Ultrabay optical drives. Thus, if the ide driver is compiled as a module and loaded after ata_piix, the DVD drive will not be recognized by either driver.

Either of the following configurations will work:

  • For kernel 2.6.14 and newer: enable ATAPI support in the SATA system using libata.atapi_enabled=1 (see below; this is experimental).
  • Compile IDE into the kernel (non-module).
  • Compile both IDE and SATA as modules and make sure IDE is loaded first (the module is called 'ide_generic').

Note that the optical drive must be in the Ultrabay during system boot (Ultrabay device swapping is currently unsupported).

No DMA on DVD drive

Using the IDE driver, DMA support cannot be enabled on an Ultrabay optical drive:

# hdparm -d1 /dev/hdc

/dev/hdc:
 setting using_dma to 1 (on)
 HDIO_SET_DMA failed: Operation not permitted
 using_dma    =  0 (off)

As a result, the optical drive is slow, and in particular, too slow to play video DVDs.

One workaround is to use employ the SATA driver (instead of the IDE driver) for the optical drive. This requires enabling two featues of the SATA driver, namely ATAPI support and PATA support, which are both in active development and far from stable. Using this will probably devour all your data and go on to eat all the food in your fridge. But if you have full backups and an empty fridge, do the following:

  • Grab the latest kernel (must be 2.6.14 or newer; the relevant code is under active development).
  • Do one of the following:
    • Configure the SATA system (and in particular ata_piix and libata) as built-in and add libata.atapi_enabled=1 to your kernel command line (e.g., in in /boot/grub/menu.lst).
    • Configure the SATA system as module (this is often the default) and add "options libata atapi_enabled=1" to your /etc/modprobe.conf (or the equivalent in your distribution).
  • Do one of the following:
    • Disable the IDE system.
    • Build the IDE driver as built-in (this is often the default) and add the hdc=noprobe kernel argument (e.g., in in /boot/grub/menu.lst).
    • Build the IDE driver as module and add "options ide hdc=noprobe" to your /etc/modprobe.conf (or the equivalent in your distribution).
  • If you chose to use modules above, regenerate your initrd file.

If this doesn't work, use lspci -vn to check whether one of the following chipsets is used in the Thinkpad:

PCI ID Name
8086:7111 Intel 82371AB/EB/MB PIIX4 IDE
8086:24db Intel 82801EB/ER (ICH5/ICH5R) IDE Controller
8086:25a2 Intel 6300ESB PATA Storage Controller

If yes, enable support for these chipsets has to be enabled by setting

#define ATA_ENABLE_PATA

in include/linux/libata.h (and report your ThinkPad model in the discussion page).

There have been reports that DVD burning doesn't work under this configuration, but it seems to work with kernel 2.6.14 and later (tested on a ThinkPad T43 and T43p with a UltraBay Slim DVD Multi-Burner Plus).

Links

No DMA on system hard disk

In some Linux kernels, both the SATA driver and the IDE driver can handle the system hard disk. With the SATA driver, it shows as /dev/sda and DMA is enabled. With the IDE driver, it shows as /dev/hda and DMA is disabled.

The simplest way to enable DMA is to force the IDE driver to ignore the system hard disk by passing the hda=noprobe kernel argument. The driver will then be handled by the SATA driver. Note that this will change its device name to /dev/sda (which may require changes in /etc/fstab and the boot loader) and may cause other problems as listed above.

(Observed on a ThinkPad T43 with Fedora Core kernel 2.6.13-1.1526_FC4.)

No SMART support

Prior to kernel 2.6.15, the Linux SATA system did not support SMART commands (e.g., via smartctl).

The necessary capability is "libata pass-through", which was incorporated into Linux 2.6.15-rc1 and later. A patch is available for older kernels:

After applying the patch, run smartctl with the "-d ata" parameter:

# smartctl -d ata -a /dev/sda

No disk power management

Prior to kernel 2.6.15, the Linux SATA system did not support power management commands on these models.

The above patches for SMART support resolves this, and in particular enables the following commands:

  • # hdparm -y (spin down)
  • # hdparm -S num (automatic spin down timeout)
  • # hdparm -B num (advanced power management level)

Note that this command is still rejected:

  • # hdparm -M num (acoustic management)

(Tested with patched kernels 2.6.13.1 and 2.6.12-4 and a 60GB 7200RPM disk model HTS726060M9AT00.)

Note that even when Laptop-mode is used, the "hddtemp" daemon (as shipped with Fedora Core 4) will wake up the disk every minute, and must thus be disabled for power management to be effective. Its accesses are not visibile through the /proc/sys/vm/block_dump facility. It is unclear whether disk temperature can be monitored without causing the disk to spin up (on the T43, none of the /proc/acpi/ibm/thermal values corresponds to the disk's built-in temperature sensor).

No disk information

Prior to kernel 2.6.15, on these models the disk information could not be read by the standard commands such as:

  • # hdparm -i /dev/sda
  • # hdparm -I /dev/sda

The latter is fixed by the above patch for SMART support.

No swapping of UltraBay device

The libata driver does not yet support hot-swapping (or warm-swapping) of PATA devices. If you use a DVD or 2nd PATA HDD via the libata (SATA) driver, to swap them in or out you must power down the machine.

If you use the ide driver for a PATA UltraBay device, hot-swapping might work using hdparm, idectl or hotswap (please report). However, DMA will be disabled on these models (see above).

If you use a SATA device in the UltraBay, libata hot-swapping might work (please report).

Swapping of the UltraBay Slim Battery does work.

BIOS error 2010 on user-installed hard disk

While not a Linux issue, note that there is an issue with installing alternative PATA (IDE) hard disks as the system drive. Unless the disk is one of the few approved disks listed inside the BIOS, you will get an BIOS error 2010 during system boot, and the disk may operate unreliably. See Problem with non-ThinkPad hard disks.