Bug 33892

Summary:	Kernel sometimes fails to find major/minor number of root device
Product:	IO/Storage	Reporter:	Aaron Barany (akb825)
Component:	Serial ATA	Assignee:	Jeff Garzik (jgarzik)
Status:	CLOSED UNREPRODUCIBLE
Severity:	high	CC:	florian, maciej.rutecki, rjw, tj
Priority:	P1
Hardware:	All
OS:	Linux
Kernel Version:	2.6.38	Subsystem:
Regression:	Yes	Bisected commit-id:
Bug Depends on:
Bug Blocks:	27352

Description Aaron Barany 2011-04-23 20:13:08 UTC

Since upgrading to kernel 2.6.38 on Arch Linux, booting sometimes fails with the following error message:
Unable to determine major/minor number of root device /dev/sda6

This happens randomly, and as a rough estimate happens around one out of every five times I boot. I haven't seen this on another computer I have running 2.6.38, but the hardware configuration is quite a bit different.

This is the output of hdparm -I /dev/sda:

ATA device, with non-removable media
	Model Number:       WDC WD1001FALS-00J7B0                   
	Serial Number:      WD-WMATV0932011
	Firmware Revision:  05.00K05
	Transport:          Serial, SATA 1.0a, SATA II Extensions, SATA Rev 2.5
Standards:
	Supported: 8 7 6 5 
	Likely used: 8
Configuration:
	Logical		max	current
	cylinders	16383	16383
	heads		16	16
	sectors/track	63	63
	--
	CHS current addressable sectors:   16514064
	LBA    user addressable sectors:  268435455
	LBA48  user addressable sectors: 1953525168
	Logical/Physical Sector size:           512 bytes
	device size with M = 1024*1024:      953869 MBytes
	device size with M = 1000*1000:     1000204 MBytes (1000 GB)
	cache/buffer size  = unknown
Capabilities:
	LBA, IORDY(can be disabled)
	Queue depth: 32
	Standby timer values: spec'd by Standard, with device specific minimum
	R/W multiple sector transfer: Max = 16	Current = 16
	Recommended acoustic management value: 128, current value: 254
	DMA: mdma0 mdma1 mdma2 udma0 udma1 udma2 udma3 udma4 udma5 *udma6 
	     Cycle time: min=120ns recommended=120ns
	PIO: pio0 pio1 pio2 pio3 pio4 
	     Cycle time: no flow control=120ns  IORDY flow control=120ns
Commands/features:
	Enabled	Supported:
	   *	SMART feature set
	    	Security Mode feature set
	   *	Power Management feature set
	   *	Write cache
	   *	Look-ahead
	   *	Host Protected Area feature set
	   *	WRITE_BUFFER command
	   *	READ_BUFFER command
	   *	NOP cmd
	   *	DOWNLOAD_MICROCODE
	    	Power-Up In Standby feature set
	   *	SET_FEATURES required to spinup after power up
	    	SET_MAX security extension
	    	Automatic Acoustic Management feature set
	   *	48-bit Address feature set
	   *	Device Configuration Overlay feature set
	   *	Mandatory FLUSH_CACHE
	   *	FLUSH_CACHE_EXT
	   *	SMART error logging
	   *	SMART self-test
	   *	General Purpose Logging feature set
	   *	64-bit World wide name
	   *	Segmented DOWNLOAD_MICROCODE
	   *	Gen1 signaling speed (1.5Gb/s)
	   *	Gen2 signaling speed (3.0Gb/s)
	   *	Native Command Queueing (NCQ)
	   *	Host-initiated interface power management
	   *	Phy event counters
	    	DMA Setup Auto-Activate optimization
	   *	Software settings preservation
	   *	SMART Command Transport (SCT) feature set
	   *	SCT Long Sector Access (AC1)
	   *	SCT LBA Segment Access (AC2)
	   *	SCT Error Recovery Control (AC3)
	   *	SCT Features Control (AC4)
	   *	SCT Data Tables (AC5)
	    	unknown 206[12] (vendor specific)
	    	unknown 206[13] (vendor specific)
Security: 
	Master password revision code = 65534
		supported
	not	enabled
	not	locked
		frozen
	not	expired: security count
		supported: enhanced erase
	194min for SECURITY ERASE UNIT. 194min for ENHANCED SECURITY ERASE UNIT.
Logical Unit WWN Device Identifier: 50014ee0011c66d3
	NAA		: 5
	IEEE OUI	: 0014ee
	Unique ID	: 0011c66d3
Checksum: correct

And this is the output of lspci -nn:

00:00.0 Host bridge [0600]: Intel Corporation 5520/5500/X58 I/O Hub to ESI Port [8086:3405] (rev 12)
00:01.0 PCI bridge [0604]: Intel Corporation 5520/5500/X58 I/O Hub PCI Express Root Port 1 [8086:3408] (rev 12)
00:03.0 PCI bridge [0604]: Intel Corporation 5520/5500/X58 I/O Hub PCI Express Root Port 3 [8086:340a] (rev 12)
00:07.0 PCI bridge [0604]: Intel Corporation 5520/5500/X58 I/O Hub PCI Express Root Port 7 [8086:340e] (rev 12)
00:14.0 PIC [0800]: Intel Corporation 5520/5500/X58 I/O Hub System Management Registers [8086:342e] (rev 12)
00:14.1 PIC [0800]: Intel Corporation 5520/5500/X58 I/O Hub GPIO and Scratch Pad Registers [8086:3422] (rev 12)
00:14.2 PIC [0800]: Intel Corporation 5520/5500/X58 I/O Hub Control Status and RAS Registers [8086:3423] (rev 12)
00:14.3 PIC [0800]: Intel Corporation 5520/5500/X58 I/O Hub Throttle Registers [8086:3438] (rev 12)
00:1a.0 USB Controller [0c03]: Intel Corporation 82801JI (ICH10 Family) USB UHCI Controller #4 [8086:3a37]
00:1a.1 USB Controller [0c03]: Intel Corporation 82801JI (ICH10 Family) USB UHCI Controller #5 [8086:3a38]
00:1a.2 USB Controller [0c03]: Intel Corporation 82801JI (ICH10 Family) USB UHCI Controller #6 [8086:3a39]
00:1a.7 USB Controller [0c03]: Intel Corporation 82801JI (ICH10 Family) USB2 EHCI Controller #2 [8086:3a3c]
00:1b.0 Audio device [0403]: Intel Corporation 82801JI (ICH10 Family) HD Audio Controller [8086:3a3e]
00:1c.0 PCI bridge [0604]: Intel Corporation 82801JI (ICH10 Family) PCI Express Root Port 1 [8086:3a40]
00:1c.1 PCI bridge [0604]: Intel Corporation 82801JI (ICH10 Family) PCI Express Port 2 [8086:3a42]
00:1c.4 PCI bridge [0604]: Intel Corporation 82801JI (ICH10 Family) PCI Express Root Port 5 [8086:3a48]
00:1c.5 PCI bridge [0604]: Intel Corporation 82801JI (ICH10 Family) PCI Express Root Port 6 [8086:3a4a]
00:1d.0 USB Controller [0c03]: Intel Corporation 82801JI (ICH10 Family) USB UHCI Controller #1 [8086:3a34]
00:1d.1 USB Controller [0c03]: Intel Corporation 82801JI (ICH10 Family) USB UHCI Controller #2 [8086:3a35]
00:1d.2 USB Controller [0c03]: Intel Corporation 82801JI (ICH10 Family) USB UHCI Controller #3 [8086:3a36]
00:1d.7 USB Controller [0c03]: Intel Corporation 82801JI (ICH10 Family) USB2 EHCI Controller #1 [8086:3a3a]
00:1e.0 PCI bridge [0604]: Intel Corporation 82801 PCI Bridge [8086:244e] (rev 90)
00:1f.0 ISA bridge [0601]: Intel Corporation 82801JIR (ICH10R) LPC Interface Controller [8086:3a16]
00:1f.2 IDE interface [0101]: Intel Corporation 82801JI (ICH10 Family) 4 port SATA IDE Controller #1 [8086:3a20]
00:1f.3 SMBus [0c05]: Intel Corporation 82801JI (ICH10 Family) SMBus Controller [8086:3a30]
00:1f.5 IDE interface [0101]: Intel Corporation 82801JI (ICH10 Family) 2 port SATA IDE Controller #2 [8086:3a26]
02:00.0 VGA compatible controller [0300]: nVidia Corporation GF104 [GeForce GTX 460] [10de:0e22] (rev a1)
02:00.1 Audio device [0403]: nVidia Corporation GF104 High Definition Audio Controller [10de:0beb] (rev a1)
05:00.0 SATA controller [0106]: JMicron Technology Corp. JMB362/JMB363 Serial ATA Controller [197b:2363] (rev 03)
05:00.1 IDE interface [0101]: JMicron Technology Corp. JMB362/JMB363 Serial ATA Controller [197b:2363] (rev 03)
06:00.0 Ethernet controller [0200]: Realtek Semiconductor Co., Ltd. RTL8111/8168B PCI Express Gigabit Ethernet controller [10ec:8168] (rev 02)
07:00.0 FireWire (IEEE 1394) [0c00]: JMicron Technology Corp. IEEE 1394 Host Controller [197b:2380] (rev 10)

Comment 1 Tejun Heo 2011-04-25 09:49:22 UTC

Hmmm... too little information.  Can you please capture kernel log on failed and successful boots?  You'll probably need to setup net or serialconsole.  The most likely cause is usb or other type of storage device getting detected before the SATA device.  If that's the case, using UUID or LABEL is the correct solution.  /dev/sdX assignment order isn't guaranteed.

Thanks.

Comment 2 Aaron Barany 2011-05-07 22:43:43 UTC

Since reporting this, I've installed updates to both the kernel and udev, and I haven't experienced this issue for over a week. At this point I think it's likely been fixed, but if I encounter it again I will try to use netconsole and post the logs.

Comment 3 Florian Mickler 2011-05-09 06:36:14 UTC

Ok, in the meantime, I'm closing this.