Re: Problems with -git14

Re: Problems with -git14

[Arjan van de Ven]

On Wed, 30 Apr 2008 16:17:46 +0100 (BST)
Hugh Dickins <hugh@veritas.com> wrote:

> One point worth noting - is it a worry?  Prior to that smpboot merge,
> my Xeon booted the two HT siblings on one physical first, then the
> two siblings on the other physical after - when i386, but alternated
> them when x86_64.  Since the merge, the x86_64 sequence is unchanged,
> but the i386 sequence is now like x86_64.  I prefer this consistency,
> and I prefer the new sequence: booting with maxcpus=2 then uses the
> independent physicals without HT sharing; but surprises in store?
> 

this is how it always was supposed to be!
At least this is how Intel specifies it to the BIOS vendors (but remember, it's the bios
that pretty much sets the cpu order; some will be weird).

Exactly for the maxcpus=2 reason... (and for systems where the cpu scheduler does 
load balancing "from 0 up" it also makes sense)

Problems with -git14

[J.A. Magallón]

Hi...

I have a couple problems with latest git (-14):

- It only recognises 2 processors out of 4 (dual Xeon HT)
- It oopses on the swapper process just on boot...

Difference in dmesg is below. If full correct dmesg or config is
needed, please ask for them. The kernel was built copying old
2.6.25 config to .config && make oldconfig. I filled the missing
gaps like PAT and others...

--- dm.txt	2008-04-30 01:47:55.000000000 +0200
+++ dm-git14.txt	2008-04-30 01:47:29.000000000 +0200
@@ -1,4 +1,4 @@
-Linux version 2.6.25-jam01 (root@werewolf) (gcc version 4.2.3 (4.2.3-6mnb1)) #6 SMP PREEMPT Mon Apr 21 20:28:14 CEST 2008
+Linux version 2.6.25-jam02 (root@werewolf) (gcc version 4.2.3 (4.2.3-6mnb1)) #1 SMP PREEMPT Wed Apr 30 00:49:19 CEST 2008
 BIOS-provided physical RAM map:
  BIOS-e820: 0000000000000000 - 000000000009f400 (usable)
  BIOS-e820: 000000000009f400 - 00000000000a0000 (reserved)
@@ -8,11 +8,9 @@
  BIOS-e820: 000000007fee3000 - 000000007fef0000 (ACPI data)
  BIOS-e820: 000000007fef0000 - 000000007ff00000 (reserved)
  BIOS-e820: 00000000fec00000 - 0000000100000000 (reserved)
+x86 PAT enabled: cpu 0, old 0x7040600070406, new 0x7010600070106
 1150MB HIGHMEM available.
 896MB LOWMEM available.
-Scan SMP from c0000000 for 1024 bytes.
-Scan SMP from c009fc00 for 1024 bytes.
-Scan SMP from c00f0000 for 65536 bytes.
 found SMP MP-table at [c00f57c0] 000f57c0
 Entering add_active_range(0, 0, 524000) 0 entries of 256 used
 Zone PFN ranges:
@@ -42,13 +40,13 @@
 ACPI: PM-Timer IO Port: 0x408
 ACPI: Local APIC address 0xfee00000
 ACPI: LAPIC (acpi_id[0x00] lapic_id[0x00] enabled)
-Processor #0 15:2 APIC version 20
+BIOS bug, APIC version is 0 for CPU#0! fixing up to 0x10. (tell your hw vendor)
 ACPI: LAPIC (acpi_id[0x01] lapic_id[0x06] enabled)
-Processor #6 15:2 APIC version 20
-ACPI: LAPIC (acpi_id[0x02] lapic_id[0x07] enabled)
-Processor #7 15:2 APIC version 20
-ACPI: LAPIC (acpi_id[0x03] lapic_id[0x01] enabled)
-Processor #1 15:2 APIC version 20
+BIOS bug, APIC version is 0 for CPU#0! fixing up to 0x10. (tell your hw vendor)
+ACPI: LAPIC (acpi_id[0x02] lapic_id[0x01] enabled)
+BIOS bug, APIC version is 0 for CPU#0! fixing up to 0x10. (tell your hw vendor)
+ACPI: LAPIC (acpi_id[0x03] lapic_id[0x07] enabled)
+BIOS bug, APIC version is 0 for CPU#0! fixing up to 0x10. (tell your hw vendor)
 ACPI: LAPIC_NMI (acpi_id[0x00] high edge lint[0x1])
 ACPI: LAPIC_NMI (acpi_id[0x01] high edge lint[0x1])
 ACPI: LAPIC_NMI (acpi_id[0x02] high edge lint[0x1])
@@ -63,6 +61,8 @@
 Enabling APIC mode:  Flat.  Using 1 I/O APICs
 Using ACPI (MADT) for SMP configuration information
 Allocating PCI resources starting at 80000000 (gap: 7ff00000:7ed00000)
+PERCPU: Allocating 39024 bytes of per cpu data
+NR_CPUS: 4, nr_cpu_ids: 4
 Built 1 zonelists in Zone order, mobility grouping on.  Total pages: 519907
 Kernel command line: video=vesafb:mtrr,ywrap vga=773 ro root=/dev/sda1
 mapped APIC to ffffb000 (fee00000)
@@ -70,72 +70,57 @@
 Enabling fast FPU save and restore... done.
 Enabling unmasked SIMD FPU exception support... done.
 Initializing CPU#0
-CPU 0 irqstacks, hard=c0458000 soft=c0454000
+CPU 0 irqstacks, hard=c043b000 soft=c0437000
 PID hash table entries: 4096 (order: 12, 16384 bytes)
-Detected 2405.510 MHz processor.
+Detected 2405.615 MHz processor.
 Console: colour dummy device 80x25
 console [tty0] enabled
 Dentry cache hash table entries: 131072 (order: 7, 524288 bytes)
 Inode-cache hash table entries: 65536 (order: 6, 262144 bytes)
-Memory: 2073904k/2096000k available (2298k kernel code, 21036k reserved, 812k data, 268k init, 1178496k highmem)
+Memory: 2074016k/2096000k available (2218k kernel code, 20936k reserved, 812k data, 232k init, 1178496k highmem)
 virtual kernel memory layout:
     fixmap  : 0xfff81000 - 0xfffff000   ( 504 kB)
     pkmap   : 0xff800000 - 0xffc00000   (4096 kB)
     vmalloc : 0xf8800000 - 0xff7fe000   ( 111 MB)
     lowmem  : 0xc0000000 - 0xf8000000   ( 896 MB)
-      .init : 0xc040e000 - 0xc0451000   ( 268 kB)
-      .data : 0xc033e8de - 0xc0409a48   ( 812 kB)
-      .text : 0xc0100000 - 0xc033e8de   (2298 kB)
+      .init : 0xc03fa000 - 0xc0434000   ( 232 kB)
+      .data : 0xc032aa15 - 0xc03f5af0   ( 812 kB)
+      .text : 0xc0100000 - 0xc032aa15   (2218 kB)
 Checking if this processor honours the WP bit even in supervisor mode...Ok.
 CPA: page pool initialized 1 of 1 pages preallocated
-SLUB: Genslabs=12, HWalign=128, Order=0-1, MinObjects=4, CPUs=4, Nodes=1
-Calibrating delay using timer specific routine.. 4813.42 BogoMIPS (lpj=2406712)
+SLUB: Genslabs=12, HWalign=128, Order=0-3, MinObjects=0, CPUs=4, Nodes=1
+Calibrating delay using timer specific routine.. 4813.29 BogoMIPS (lpj=2406649)
 Mount-cache hash table entries: 512
 CPU: Trace cache: 12K uops, L1 D cache: 8K
 CPU: L2 cache: 512K
 CPU: Physical Processor ID: 0
 Compat vDSO mapped to ffffe000.
 Checking 'hlt' instruction... OK.
-Freeing SMP alternatives: 11k freed
+Freeing SMP alternatives: 10k freed
 ACPI: Core revision 20070126
+ENABLING IO-APIC IRQs
+..TIMER: vector=0x31 apic1=0 pin1=2 apic2=-1 pin2=-1
 CPU0: Intel(R) Xeon(TM) CPU 2.40GHz stepping 09
+CPU 1 irqstacks, hard=c043c000 soft=c0438000
 Booting processor 1/1 ip 2000
-CPU 1 irqstacks, hard=c0459000 soft=c0455000
 Initializing CPU#1
-Calibrating delay using timer specific routine.. 4810.24 BogoMIPS (lpj=2405121)
+Calibrating delay using timer specific routine.. 4810.28 BogoMIPS (lpj=2405142)
 CPU: Trace cache: 12K uops, L1 D cache: 8K
 CPU: L2 cache: 512K
 CPU: Physical Processor ID: 0
+x86 PAT enabled: cpu 1, old 0x7040600070406, new 0x7010600070106
 CPU1: Intel(R) Xeon(TM) CPU 2.40GHz stepping 09
-Booting processor 2/6 ip 2000
-CPU 2 irqstacks, hard=c045a000 soft=c0456000
-Initializing CPU#2
-Calibrating delay using timer specific routine.. 4810.31 BogoMIPS (lpj=2405158)
-CPU: Trace cache: 12K uops, L1 D cache: 8K
-CPU: L2 cache: 512K
-CPU: Physical Processor ID: 3
-CPU2: Intel(R) Xeon(TM) CPU 2.40GHz stepping 09
-Booting processor 3/7 ip 2000
-CPU 3 irqstacks, hard=c045b000 soft=c0457000
-Initializing CPU#3
-Calibrating delay using timer specific routine.. 4810.31 BogoMIPS (lpj=2405158)
-CPU: Trace cache: 12K uops, L1 D cache: 8K
-CPU: L2 cache: 512K
-CPU: Physical Processor ID: 3
-CPU3: Intel(R) Xeon(TM) CPU 2.40GHz stepping 09
-Total of 4 processors activated (19244.29 BogoMIPS).
-ENABLING IO-APIC IRQs
-..TIMER: vector=0x31 apic1=0 pin1=2 apic2=-1 pin2=-1
 checking TSC synchronization [CPU#0 -> CPU#1]: passed.
-checking TSC synchronization [CPU#0 -> CPU#2]: passed.
-checking TSC synchronization [CPU#0 -> CPU#3]: passed.
-Brought up 4 CPUs
-net_namespace: 160 bytes
+native_cpu_up: bad cpu 2
+native_cpu_up: bad cpu 3
+Brought up 2 CPUs
+Total of 2 processors activated (9623.58 BogoMIPS).
+net_namespace: 200 bytes
 NET: Registered protocol family 16
 No dock devices found.
 ACPI: bus type pci registered
 PCI: PCI BIOS revision 2.10 entry at 0xfb7f0, last bus=3
-PCI: Using configuration type 1
+PCI: Using configuration type 1 for base access
 Setting up standard PCI resources
 ACPI: EC: Look up EC in DSDT
 ACPI: Interpreter enabled
@@ -167,7 +152,6 @@
 usbcore: registered new interface driver hub
 usbcore: registered new device driver usb
 PCI: Using ACPI for IRQ routing
-PCI: If a device doesn't work, try "pci=routeirq".  If it helps, post a report
 hpet clockevent registered
 hpet0: at MMIO 0xfed00000, IRQs 2, 8, 0
 hpet0: 3 64-bit timers, 14318180 Hz
@@ -213,7 +197,9 @@
 TCP bind hash table entries: 65536 (order: 7, 524288 bytes)
 TCP: Hash tables configured (established 131072 bind 65536)
 TCP reno registered
+NET: Registered protocol family 1
 highmem bounce pool size: 64 pages
+msgmni has been set to 1750 for ipc namespace c03dadc0
 io scheduler noop registered
 io scheduler anticipatory registered
 io scheduler deadline registered
@@ -231,10 +217,8 @@
 Non-volatile memory driver v1.2
 intel_rng: FWH not detected
 ACPI: PCI Interrupt 0000:03:0a.0[A] -> GSI 22 (level, low) -> IRQ 22
-Switched to high resolution mode on CPU 2
-Switched to high resolution mode on CPU 3
-Switched to high resolution mode on CPU 0
 Switched to high resolution mode on CPU 1
+Switched to high resolution mode on CPU 0
 scsi0 : Adaptec AIC79XX PCI-X SCSI HBA DRIVER, Rev 3.0
         <Adaptec 29320 Ultra320 SCSI adapter>
         aic7902: Ultra320 Wide Channel A, SCSI Id=7, PCI 33 or 66Mhz, 512 SCBs
@@ -243,19 +227,81 @@
         <Adaptec 29320 Ultra320 SCSI adapter>
         aic7902: Ultra320 Wide Channel B, SCSI Id=7, PCI 33 or 66Mhz, 512 SCBs
 scsi 1:0:0:0: Direct-Access     SEAGATE  ST336807LW       0C01 PQ: 0 ANSI: 3
- target1:0:0: asynchronous
+------------[ cut here ]------------
+WARNING: at include/linux/blkdev.h:427 blk_queue_init_tags+0x110/0x11f()
+Modules linked in:
+Pid: 1, comm: swapper Not tainted 2.6.25-jam02 #1
+ [<c011e618>] warn_on_slowpath+0x4d/0x66
+ [<c0133078>] __atomic_notifier_call_chain+0x27/0x48
+ [<c01330b0>] atomic_notifier_call_chain+0x17/0x1b
+ [<c024367e>] notify_update+0x1f/0x23
+ [<c02438c7>] vt_console_print+0x1dd/0x2ab
+ [<c02436ea>] vt_console_print+0x0/0x2ab
+ [<c0132c3e>] up+0x9/0x2b
+ [<c01eca3c>] init_tag_map+0x4e/0x95
+ [<c01ecb61>] __blk_queue_init_tags+0x27/0x4e
+ [<c01ecc98>] blk_queue_init_tags+0x110/0x11f
+ [<c027e9fb>] ahd_platform_set_tags+0x177/0x1a7
+ [<c027f0a7>] ahd_linux_slave_configure+0xcd/0x131
+ [<c02576fe>] scsi_probe_and_add_lun+0x706/0x964
+ [<c0257b27>] __scsi_scan_target+0xd9/0x5d9
+ [<c019c3b3>] sysfs_ilookup_test+0x0/0xd
+ [<c019ce3a>] sysfs_addrm_finish+0x14/0x1c7
+ [<c019c6bd>] sysfs_find_dirent+0x1e/0x27
+ [<c019c701>] sysfs_add_one+0x3b/0x8b
+ [<c019c24c>] sysfs_add_file_mode+0x4d/0x76
+ [<c019da1c>] internal_create_group+0xd7/0x196
+ [<c0322dd2>] klist_next+0x53/0x90
+ [<c025809f>] scsi_scan_channel+0x78/0x8d
+ [<c025815c>] scsi_scan_host_selected+0xa8/0xd1
+ [<c02581ed>] do_scsi_scan_host+0x68/0x6a
+ [<c027e26c>] ahd_linux_register_host+0x267/0x2db
+ [<c02808cf>] ahd_pci_map_int+0x2c/0x50
+ [<c0279bba>] ahd_pci_config+0x533/0x824
+ [<c01f6736>] kobject_get+0xf/0x13
+ [<c024a495>] get_device+0xe/0x14
+ [<c0202579>] pci_dev_get+0xf/0x13
+ [<c0280a96>] ahd_linux_pci_dev_probe+0x139/0x17f
+ [<c019ce3a>] sysfs_addrm_finish+0x14/0x1c7
+ [<c019c6bd>] sysfs_find_dirent+0x1e/0x27
+ [<c019c701>] sysfs_add_one+0x3b/0x8b
+ [<c019d3a3>] sysfs_create_link+0x89/0x106
+ [<c0202819>] pci_match_device+0x9c/0xad
+ [<c0202880>] pci_device_probe+0x40/0x60
+ [<c024c9d3>] driver_probe_device+0x76/0x152
+ [<c024cb05>] __driver_attach+0x56/0x58
+ [<c024c40d>] bus_for_each_dev+0x39/0x57
+ [<c0202840>] pci_device_probe+0x0/0x60
+ [<c024c896>] driver_attach+0x16/0x1a
+ [<c024caaf>] __driver_attach+0x0/0x58
+ [<c024bf1a>] bus_add_driver+0x19c/0x214
+ [<c0202534>] pci_device_remove+0x0/0x36
+ [<c0202840>] pci_device_probe+0x0/0x60
+ [<c024cc24>] driver_register+0x3b/0xd3
+ [<c020274b>] __pci_register_driver+0x32/0x64
+ [<c040eb5f>] ahd_linux_init+0x53/0x6f
+ [<c03faa36>] kernel_init+0x11d/0x287
+ [<c01174c2>] finish_task_switch+0x1f/0x6d
+ [<c0117711>] schedule_tail+0x16/0x44
+ [<c0102c6a>] ret_from_fork+0x6/0x1c
+ [<c03fa919>] kernel_init+0x0/0x287
+ [<c03fa919>] kernel_init+0x0/0x287
+ [<c0103947>] kernel_thread_helper+0x7/0x10
+ =======================
+---[ end trace 73ab2f7863b8a5fa ]---
+scsi target1:0:0: asynchronous
 scsi1:A:0:0: Tagged Queuing enabled.  Depth 32
- target1:0:0: Beginning Domain Validation
- target1:0:0: wide asynchronous
- target1:0:0: FAST-160 WIDE SCSI 320.0 MB/s DT IU QAS RDSTRM WRFLOW PCOMP (6.25 ns, offset 63)
- target1:0:0: Ending Domain Validation
+scsi target1:0:0: Beginning Domain Validation
+scsi target1:0:0: wide asynchronous
+scsi target1:0:0: FAST-160 WIDE SCSI 320.0 MB/s DT IU QAS RDSTRM WRFLOW PCOMP (6.25 ns, offset 63)
+scsi target1:0:0: Ending Domain Validation
 scsi 1:0:1:0: Direct-Access     SEAGATE  ST336807LW       0C01 PQ: 0 ANSI: 3
- target1:0:1: asynchronous
+scsi target1:0:1: asynchronous
 scsi1:A:1:0: Tagged Queuing enabled.  Depth 32
- target1:0:1: Beginning Domain Validation
- target1:0:1: wide asynchronous
- target1:0:1: FAST-160 WIDE SCSI 320.0 MB/s DT IU QAS RDSTRM WRFLOW PCOMP (6.25 ns, offset 63)
- target1:0:1: Ending Domain Validation
+scsi target1:0:1: Beginning Domain Validation
+scsi target1:0:1: wide asynchronous
+scsi target1:0:1: FAST-160 WIDE SCSI 320.0 MB/s DT IU QAS RDSTRM WRFLOW PCOMP (6.25 ns, offset 63)
+scsi target1:0:1: Ending Domain Validation
 Driver 'sd' needs updating - please use bus_type methods
 sd 1:0:0:0: [sda] 71687372 512-byte hardware sectors (36704 MB)
 sd 1:0:0:0: [sda] Write Protect is off
@@ -353,6 +399,7 @@
 usb usb3: configuration #1 chosen from 1 choice
 hub 3-0:1.0: USB hub found
 hub 3-0:1.0: 2 ports detected
+hub 1-0:1.0: unable to enumerate USB device on port 1
 ACPI: PCI Interrupt 0000:00:1d.2[C] -> GSI 18 (level, low) -> IRQ 18
 PCI: Setting latency timer of device 0000:00:1d.2 to 64
 uhci_hcd 0000:00:1d.2: UHCI Host Controller
@@ -361,6 +408,7 @@
 usb usb4: configuration #1 chosen from 1 choice
 hub 4-0:1.0: USB hub found
 hub 4-0:1.0: 2 ports detected
+hub 1-0:1.0: unable to enumerate USB device on port 4
 ACPI: PCI Interrupt 0000:00:1d.3[A] -> GSI 16 (level, low) -> IRQ 16
 PCI: Setting latency timer of device 0000:00:1d.3 to 64
 uhci_hcd 0000:00:1d.3: UHCI Host Controller
@@ -389,61 +437,61 @@
 input: Mitsumi Electric Apple Extended USB Keyboard as /devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.3/2-1.3:1.1/input/input3
 input: USB HID v1.10 Device [Mitsumi Electric Apple Extended USB Keyboard] on usb-0000:00:1d.0-1.3
 usbcore: registered new interface driver usbhid
-drivers/hid/usbhid/hid-core.c: v2.6:USB HID core driver
+usbhid: v2.6:USB HID core driver
 TCP cubic registered
-NET: Registered protocol family 1
 NET: Registered protocol family 17
 p4-clockmod: P4/Xeon(TM) CPU On-Demand Clock Modulation available
 Using IPI Shortcut mode
 kjournald starting.  Commit interval 5 seconds
 EXT3-fs: mounted filesystem with ordered data mode.
 VFS: Mounted root (ext3 filesystem) readonly.
-Freeing unused kernel memory: 268k freed
-sd 1:0:0:0: Attached scsi generic sg0 type 0
-sd 1:0:1:0: Attached scsi generic sg1 type 0
-sd 2:0:0:0: Attached scsi generic sg2 type 0
-sr 2:0:1:0: Attached scsi generic sg3 type 5
-sd 4:0:0:0: Attached scsi generic sg4 type 0
+Freeing unused kernel memory: 232k freed
 Linux agpgart interface v0.103
-ACPI: PCI Interrupt 0000:00:1f.3[B] -> GSI 17 (level, low) -> IRQ 17
-usblp0: USB Bidirectional printer dev 2 if 0 alt 0 proto 2 vid 0x03F0 pid 0x3404
-usbcore: registered new interface driver usblp
-rtc_cmos 00:03: rtc core: registered rtc_cmos as rtc0
-rtc0: alarms up to one month
 agpgart: Detected an Intel i875 Chipset.
 agpgart: AGP aperture is 32M @ 0xf0000000
 Intel(R) PRO/1000 Network Driver - version 7.3.20-k2
 Copyright (c) 1999-2006 Intel Corporation.
 ACPI: PCI Interrupt 0000:02:01.0[A] -> GSI 18 (level, low) -> IRQ 18
 PCI: Setting latency timer of device 0000:02:01.0 to 64
+usblp0: USB Bidirectional printer dev 2 if 0 alt 0 proto 2 vid 0x03F0 pid 0x3404
+usbcore: registered new interface driver usblp
 e1000: 0000:02:01.0: e1000_probe: (PCI:33MHz:32-bit) 00:0e:a6:8b:e9:85
+sd 1:0:0:0: Attached scsi generic sg0 type 0
+sd 1:0:1:0: Attached scsi generic sg1 type 0
+sd 2:0:0:0: Attached scsi generic sg2 type 0
+sr 2:0:1:0: Attached scsi generic sg3 type 5
+sd 4:0:0:0: Attached scsi generic sg4 type 0
+e1000: eth0: e1000_probe: Intel(R) PRO/1000 Network Connection
+ACPI: PCI Interrupt 0000:03:03.0[A] -> GSI 20 (level, low) -> IRQ 20
+ohci1394: fw-host0: OHCI-1394 1.1 (PCI): IRQ=[20]  MMIO=[f6008000-f60087ff]  Max Packet=[2048]  IR/IT contexts=[4/8]
+ACPI: PCI Interrupt 0000:03:0d.0[A] -> GSI 21 (level, low) -> IRQ 21
+3c59x: Donald Becker and others.
+0000:03:0d.0: 3Com PCI 3c980C Python-T at f881e000.
+ACPI: PCI Interrupt 0000:00:1f.3[B] -> GSI 17 (level, low) -> IRQ 17
+gameport: EMU10K1 is pci0000:03:0b.1/gameport0, io 0x9400, speed 994kHz
+rtc_cmos 00:03: rtc core: registered rtc_cmos as rtc0
+rtc0: alarms up to one month
 Serial: 8250/16550 driver $Revision: 1.90 $ 4 ports, IRQ sharing disabled
 serial8250: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A
 serial8250: ttyS1 at I/O 0x2f8 (irq = 3) is a 16550A
 00:07: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A
 00:08: ttyS1 at I/O 0x2f8 (irq = 3) is a 16550A
-parport_pc 00:09: reported by Plug and Play ACPI
-parport0: PC-style at 0x378, irq 7 [PCSPP(,...)]
-e1000: eth0: e1000_probe: Intel(R) PRO/1000 Network Connection
-ACPI: PCI Interrupt 0000:03:0d.0[A] -> GSI 21 (level, low) -> IRQ 21
-3c59x: Donald Becker and others.
-0000:03:0d.0: 3Com PCI 3c980C Python-T at f882e000.
-udev: renamed network interface eth0 to eth1
-ACPI: PCI Interrupt 0000:03:03.0[A] -> GSI 20 (level, low) -> IRQ 20
-ohci1394: fw-host0: OHCI-1394 1.1 (PCI): IRQ=[20]  MMIO=[f6008000-f60087ff]  Max Packet=[2048]  IR/IT contexts=[4/8]
-ACPI: PCI Interrupt 0000:03:0b.0[A] -> GSI 23 (level, low) -> IRQ 23
-gameport: EMU10K1 is pci0000:03:0b.1/gameport0, io 0x9400, speed 1028kHz
 ACPI: PCI Interrupt 0000:00:1f.5[B] -> GSI 17 (level, low) -> IRQ 17
 PCI: Setting latency timer of device 0000:00:1f.5 to 64
+parport_pc 00:09: reported by Plug and Play ACPI
+parport0: PC-style at 0x378, irq 7 [PCSPP(,...)]
+udev: renamed network interface eth1 to eth0
+udev: renamed network interface eth0_rename to eth1
 AC'97 0 analog subsections not ready
-intel8x0_measure_ac97_clock: measured 50135 usecs
+intel8x0_measure_ac97_clock: measured 50110 usecs
 intel8x0: clocking to 48000
-rtc: I/O resource 70 is not free.
+ACPI: PCI Interrupt 0000:03:0b.0[A] -> GSI 23 (level, low) -> IRQ 23
+firmware: requesting intel-ucode/0f-02-09
+firmware: requesting intel-ucode/0f-02-09
 IA-32 Microcode Update Driver: v1.14a <tigran@aivazian.fsnet.co.uk>
-rtc: I/O resource 70 is not free.
+ieee1394: Host added: ID:BUS[0-00:1023]  GUID[00e018000063814f]
 Floppy drive(s): fd0 is 1.44M
 FDC 0 is a post-1991 82077
-ieee1394: Host added: ID:BUS[0-00:1023]  GUID[00e018000063814f]
 EXT3 (no)user_xattr options not supported
 EXT3 FS on sda1, internal journal
 EXT3 (no)user_xattr options not supported



-- 
J.A. Magallon <jamagallon()ono!com>     \               Software is like sex:
                                         \         It's better when it's free
Mandriva Linux release 2008.1 (Cooker) for i586
Linux 2.6.23-jam05 (gcc 4.2.2 20071128 (4.2.2-2mdv2008.1)) SMP PREEMPT

Re: Problems with -git14

[Hugh Dickins]

[-- Attachment #1: Type: TEXT/PLAIN, Size: 3173 bytes --]

On Wed, 30 Apr 2008, J.A. Magallón wrote:
> 
> I have a couple problems with latest git (-14):
> 
> - It only recognises 2 processors out of 4 (dual Xeon HT)
> - It oopses on the swapper process just on boot...
> 
> Difference in dmesg is below. If full correct dmesg or config is
> needed, please ask for them. The kernel was built copying old
> 2.6.25 config to .config && make oldconfig. I filled the missing
> gaps like PAT and others...
> 
> -Brought up 4 CPUs
> +native_cpu_up: bad cpu 2
> +native_cpu_up: bad cpu 3
> +Brought up 2 CPUs

Yes, I've been getting this for some days too: only 2 processors on
dual Xeon HT in 32-bit mode; whereas x86_64 finds all 4 just fine.
Ran lots of testing on 2.6.25-mm1 before I noticed it there.

I bisected for a while, but it got confusing (arrived at a bisect
point which gave only 1 processor: smpboot code getting rearranged),
so I was forced (quel horreur!) to investigate properly.  I've just
now had success with the patch below, please give it a try:
but it'll need an Ack from Glauber before it can go in.

> +WARNING: at include/linux/blkdev.h:427 blk_queue_init_tags+0x110/0x11f()

I presume this warning and backtrace is what you report as an oops:
I think you'll find Linus included a fix for this one overnight, and
it should have gone away in 2.6.25-git15 (but I didn't see it myself).

Hugh

[PATCH] x86_32: fix HT cpu booting

Since recent smpboot 32/64-bit merge, my dual Xeon with HT has been
booting only 2 of its 4 cpus (when running an i386 kernel; but x86_64
is okay).  J.A. Magallón reports the same.

native_cpu_up: bad cpu 2
native_cpu_up: bad cpu 3

The mach-default cpu_present_to_apicid() was just returning cpu number
(2, 3) instead of apicid (6, 7): looks like we now need the x86_64 code
even for the i386 case.

Comparing with other versions of cpu_present_to_apicid(), it seems a
good idea to include an NR_CPUS test too, since cpu_present() doesn't
include that; but that wasn't a problem here, and may no problem at all.

One point worth noting - is it a worry?  Prior to that smpboot merge,
my Xeon booted the two HT siblings on one physical first, then the
two siblings on the other physical after - when i386, but alternated
them when x86_64.  Since the merge, the x86_64 sequence is unchanged,
but the i386 sequence is now like x86_64.  I prefer this consistency,
and I prefer the new sequence: booting with maxcpus=2 then uses the
independent physicals without HT sharing; but surprises in store?

Signed-off-by: Hugh Dickins <hugh@veritas.com>

--- 2.6.25-git/include/asm-x86/mach-default/mach_apic.h	2008-04-23 07:24:16.000000000 +0100
+++ linux/include/asm-x86/mach-default/mach_apic.h	2008-04-30 14:55:14.000000000 +0100
@@ -109,13 +109,8 @@ static inline int cpu_to_logical_apicid(
 
 static inline int cpu_present_to_apicid(int mps_cpu)
 {
-#ifdef CONFIG_X86_64
-	if (cpu_present(mps_cpu))
+	if (mps_cpu < NR_CPUS && cpu_present(mps_cpu))
 		return (int)per_cpu(x86_bios_cpu_apicid, mps_cpu);
-#else
-	if (mps_cpu < get_physical_broadcast())
-		return  mps_cpu;
-#endif
 	else
 		return BAD_APICID;
 }

Re: Problems with -git14

[Glauber Costa]

Hugh Dickins wrote:
> On Wed, 30 Apr 2008, J.A. Magallón wrote:
>> I have a couple problems with latest git (-14):
>>
>> - It only recognises 2 processors out of 4 (dual Xeon HT)
>> - It oopses on the swapper process just on boot...
>>
>> Difference in dmesg is below. If full correct dmesg or config is
>> needed, please ask for them. The kernel was built copying old
>> 2.6.25 config to .config && make oldconfig. I filled the missing
>> gaps like PAT and others...
>>
>> -Brought up 4 CPUs
>> +native_cpu_up: bad cpu 2
>> +native_cpu_up: bad cpu 3
>> +Brought up 2 CPUs
> 
> Yes, I've been getting this for some days too: only 2 processors on
> dual Xeon HT in 32-bit mode; whereas x86_64 finds all 4 just fine.
> Ran lots of testing on 2.6.25-mm1 before I noticed it there.
> 
> I bisected for a while, but it got confusing (arrived at a bisect
> point which gave only 1 processor: smpboot code getting rearranged),
> so I was forced (quel horreur!) to investigate properly.  I've just
> now had success with the patch below, please give it a try:
> but it'll need an Ack from Glauber before it can go in.
> 
>> +WARNING: at include/linux/blkdev.h:427 blk_queue_init_tags+0x110/0x11f()
> 
> I presume this warning and backtrace is what you report as an oops:
> I think you'll find Linus included a fix for this one overnight, and
> it should have gone away in 2.6.25-git15 (but I didn't see it myself).
> 
> Hugh
> 
> [PATCH] x86_32: fix HT cpu booting
> 
> Since recent smpboot 32/64-bit merge, my dual Xeon with HT has been
> booting only 2 of its 4 cpus (when running an i386 kernel; but x86_64
> is okay).  J.A. Magallón reports the same.
> 
> native_cpu_up: bad cpu 2
> native_cpu_up: bad cpu 3
> 
> The mach-default cpu_present_to_apicid() was just returning cpu number
> (2, 3) instead of apicid (6, 7): looks like we now need the x86_64 code
> even for the i386 case.
> 
> Comparing with other versions of cpu_present_to_apicid(), it seems a
> good idea to include an NR_CPUS test too, since cpu_present() doesn't
> include that; but that wasn't a problem here, and may no problem at all.
> 
> One point worth noting - is it a worry?  Prior to that smpboot merge,
> my Xeon booted the two HT siblings on one physical first, then the
> two siblings on the other physical after - when i386, but alternated
> them when x86_64.  Since the merge, the x86_64 sequence is unchanged,
> but the i386 sequence is now like x86_64.  I prefer this consistency,
> and I prefer the new sequence: booting with maxcpus=2 then uses the
> independent physicals without HT sharing; but surprises in store?
> 
> Signed-off-by: Hugh Dickins <hugh@veritas.com>
> 
> --- 2.6.25-git/include/asm-x86/mach-default/mach_apic.h	2008-04-23 07:24:16.000000000 +0100
> +++ linux/include/asm-x86/mach-default/mach_apic.h	2008-04-30 14:55:14.000000000 +0100
> @@ -109,13 +109,8 @@ static inline int cpu_to_logical_apicid(
>  
>  static inline int cpu_present_to_apicid(int mps_cpu)
>  {
> -#ifdef CONFIG_X86_64
> -	if (cpu_present(mps_cpu))
> +	if (mps_cpu < NR_CPUS && cpu_present(mps_cpu))
>  		return (int)per_cpu(x86_bios_cpu_apicid, mps_cpu);
> -#else
> -	if (mps_cpu < get_physical_broadcast())
> -		return  mps_cpu;
> -#endif
>  	else
>  		return BAD_APICID;
>  }

Hugh, thanks for tracing this. The patch looks sane to me

However, since this problem was raised, I'm still concerned that visws 
may have the same problem, since it uses the same logic that i386 
mach_default used to. (and I did not touched, since x86_64 code went int 
o mach_default).

Could anyone with access to such hardware give it a try ?

Re: Problems with -git14

[Ingo Molnar]

* Hugh Dickins <hugh@veritas.com> wrote:

>  static inline int cpu_present_to_apicid(int mps_cpu)
>  {
> -#ifdef CONFIG_X86_64
> -	if (cpu_present(mps_cpu))
> +	if (mps_cpu < NR_CPUS && cpu_present(mps_cpu))
>  		return (int)per_cpu(x86_bios_cpu_apicid, mps_cpu);
> -#else
> -	if (mps_cpu < get_physical_broadcast())
> -		return  mps_cpu;
> -#endif
>  	else
>  		return BAD_APICID;
>  }

applied. Thanks Hugh for the detective work! I love fixes that only 
remove code ;-)

	Ingo

Re: Problems with -git14

[Ingo Molnar]

* Hugh Dickins <hugh@veritas.com> wrote:

> One point worth noting - is it a worry?  Prior to that smpboot merge, 
> my Xeon booted the two HT siblings on one physical first, then the two 
> siblings on the other physical after - when i386, but alternated them 
> when x86_64.  Since the merge, the x86_64 sequence is unchanged, but 
> the i386 sequence is now like x86_64.  I prefer this consistency, and 
> I prefer the new sequence: booting with maxcpus=2 then uses the 
> independent physicals without HT sharing; but surprises in store?

yep - but right now our view is that such surprises are worth having in 
this case. Basically we now did the more or less "mechanical" 
unification of the two SMP boot codebases, while trying to keep the 
stability track record of both, as much as possible.

The 64-bit SMP boot code (the one which came from arch/x86_64) is 
cleaner, so the plan is to slowly but surely gravitate towards the 
cleaner code - such as with your fix - while not dropping quirks and 
legacies.

It's now possible to do that without impacting the stability (and 
legacy) track record of the 32-bit code too much, because now the code 
is placed next to each other and the differences are plain visible via 
ugly #ifdefs. Whatever change we do is small and revertable.

... but it's still not easy to modify the engine of a race car, in the 
middle of the race - so please be on the lookout and any help is welcome 
;-)

	Ingo

Re: Problems with -git14

[J.A. Magallón]

On Wed, 30 Apr 2008 16:17:46 +0100 (BST), Hugh Dickins <hugh@veritas.com> wrote:

> On Wed, 30 Apr 2008, J.A. Magallón wrote:
> > 
> > I have a couple problems with latest git (-14):
> > 
> > - It only recognises 2 processors out of 4 (dual Xeon HT)
 
> [PATCH] x86_32: fix HT cpu booting
> 
> Since recent smpboot 32/64-bit merge, my dual Xeon with HT has been
> booting only 2 of its 4 cpus (when running an i386 kernel; but x86_64
> is okay).  J.A. Magallón reports the same.
> 
> native_cpu_up: bad cpu 2
> native_cpu_up: bad cpu 3
> 
> The mach-default cpu_present_to_apicid() was just returning cpu number
> (2, 3) instead of apicid (6, 7): looks like we now need the x86_64 code
> even for the i386 case.
> 

One question that always bugs me: do I have to set NR_CPUS=8 to pick
apicid number 7, and let the map just flag the ones I have, or will
it work with NR_CPUS=4 ?

-- 
J.A. Magallon <jamagallon()ono!com>     \               Software is like sex:
                                         \         It's better when it's free
Mandriva Linux release 2008.1 (Cooker) for i586
Linux 2.6.23-jam05 (gcc 4.2.2 20071128 (4.2.2-2mdv2008.1)) SMP PREEMPT

Re: Problems with -git14

[J.A. Magallón]

On Wed, 30 Apr 2008 16:17:46 +0100 (BST), Hugh Dickins <hugh@veritas.com> wrote:

> On Wed, 30 Apr 2008, J.A. Magallón wrote:
> > 
> > I have a couple problems with latest git (-14):
> > 
> > - It only recognises 2 processors out of 4 (dual Xeon HT)
> > - It oopses on the swapper process just on boot...
> > 
> > Difference in dmesg is below. If full correct dmesg or config is
> > needed, please ask for them. The kernel was built copying old
> > 2.6.25 config to .config && make oldconfig. I filled the missing
> > gaps like PAT and others...
> > 
> > -Brought up 4 CPUs
> > +native_cpu_up: bad cpu 2
> > +native_cpu_up: bad cpu 3
> > +Brought up 2 CPUs
> 
> Yes, I've been getting this for some days too: only 2 processors on
> dual Xeon HT in 32-bit mode; whereas x86_64 finds all 4 just fine.
> Ran lots of testing on 2.6.25-mm1 before I noticed it there.
> 
> I bisected for a while, but it got confusing (arrived at a bisect
> point which gave only 1 processor: smpboot code getting rearranged),
> so I was forced (quel horreur!) to investigate properly.  I've just
> now had success with the patch below, please give it a try:
> but it'll need an Ack from Glauber before it can go in.
> 
> > +WARNING: at include/linux/blkdev.h:427 blk_queue_init_tags+0x110/0x11f()
> 
> I presume this warning and backtrace is what you report as an oops:
> I think you'll find Linus included a fix for this one overnight, and
> it should have gone away in 2.6.25-git15 (but I didn't see it myself).
> 
> Hugh

-git16 plus your patch gives me my 4 cpus again.
But I still get the warning:

scsi0 : Adaptec AIC79XX PCI-X SCSI HBA DRIVER, Rev 3.0
        <Adaptec 29320 Ultra320 SCSI adapter>
        aic7902: Ultra320 Wide Channel A, SCSI Id=7, PCI 33 or 66Mhz, 512 SCBs
ACPI: PCI Interrupt 0000:03:0a.1[B] -> GSI 23 (level, low) -> IRQ 23
scsi1 : Adaptec AIC79XX PCI-X SCSI HBA DRIVER, Rev 3.0
        <Adaptec 29320 Ultra320 SCSI adapter>
        aic7902: Ultra320 Wide Channel B, SCSI Id=7, PCI 33 or 66Mhz, 512 SCBs
scsi 1:0:0:0: Direct-Access     SEAGATE  ST336807LW       0C01 PQ: 0 ANSI: 3
------------[ cut here ]------------
WARNING: at include/linux/blkdev.h:431 blk_queue_init_tags+0x110/0x11f()
Modules linked in:
Pid: 1, comm: swapper Not tainted 2.6.25-jam03 #1
 [<c011e618>] warn_on_slowpath+0x4d/0x66
 [<c0132e68>] __atomic_notifier_call_chain+0x27/0x48
 [<c0132ea0>] atomic_notifier_call_chain+0x17/0x1b
 [<c024a7be>] notify_update+0x1f/0x23
 [<c024aa07>] vt_console_print+0x1dd/0x2ab
 [<c024a82a>] vt_console_print+0x0/0x2ab
 [<c0132a2e>] up+0x9/0x2b
 [<c01f314c>] init_tag_map+0x4e/0x95
 [<c01f3271>] __blk_queue_init_tags+0x27/0x4e
 [<c01f33a8>] blk_queue_init_tags+0x110/0x11f
 [<c0285b9b>] ahd_platform_set_tags+0x177/0x1a7
 [<c0286247>] ahd_linux_slave_configure+0xcd/0x131
 [<c025e89e>] scsi_probe_and_add_lun+0x706/0x964
 [<c025ecc7>] __scsi_scan_target+0xd9/0x5d9
 [<c019ce63>] sysfs_ilookup_test+0x0/0xd
 [<c019d8ea>] sysfs_addrm_finish+0x14/0x1c7
 [<c019d16d>] sysfs_find_dirent+0x1e/0x27
 [<c019d1b1>] sysfs_add_one+0x3b/0x8b
 [<c019ccfc>] sysfs_add_file_mode+0x4d/0x76
 [<c019e4cc>] internal_create_group+0xd7/0x196
 [<c032a1b2>] klist_next+0x53/0x90
 [<c025f23f>] scsi_scan_channel+0x78/0x8d
 [<c025f2fc>] scsi_scan_host_selected+0xa8/0xd1
 [<c025f38d>] do_scsi_scan_host+0x68/0x6a
 [<c028540c>] ahd_linux_register_host+0x267/0x2db
 [<c0287a6f>] ahd_pci_map_int+0x2c/0x50
 [<c0280d5a>] ahd_pci_config+0x533/0x824
 [<c01fce96>] kobject_get+0xf/0x13
 [<c0251635>] get_device+0xe/0x14
 [<c0208da9>] pci_dev_get+0xf/0x13
 [<c0287c36>] ahd_linux_pci_dev_probe+0x139/0x17f
 [<c019d8ea>] sysfs_addrm_finish+0x14/0x1c7
 [<c019d16d>] sysfs_find_dirent+0x1e/0x27
 [<c019d1b1>] sysfs_add_one+0x3b/0x8b
 [<c019de53>] sysfs_create_link+0x89/0x106
 [<c0209049>] pci_match_device+0x9c/0xad
 [<c02090b0>] pci_device_probe+0x40/0x60
 [<c0253b73>] driver_probe_device+0x76/0x152
 [<c0253ca5>] __driver_attach+0x56/0x58
 [<c02535ad>] bus_for_each_dev+0x39/0x57
 [<c0209070>] pci_device_probe+0x0/0x60
 [<c0253a36>] driver_attach+0x16/0x1a
 [<c0253c4f>] __driver_attach+0x0/0x58
 [<c02530ba>] bus_add_driver+0x19c/0x214
 [<c0208d64>] pci_device_remove+0x0/0x36
 [<c0209070>] pci_device_probe+0x0/0x60
 [<c0253dc4>] driver_register+0x3b/0xd3
 [<c0208f7b>] __pci_register_driver+0x32/0x64
 [<c041abff>] ahd_linux_init+0x53/0x6f
 [<c0406a36>] kernel_init+0x11d/0x287
 [<c01174c2>] finish_task_switch+0x1f/0x6d
 [<c0117711>] schedule_tail+0x16/0x44
 [<c0102c62>] ret_from_fork+0x6/0x1c
 [<c0406919>] kernel_init+0x0/0x287
 [<c0406919>] kernel_init+0x0/0x287
 [<c010393f>] kernel_thread_helper+0x7/0x18
 =======================
---[ end trace e7ca32af98aeff40 ]---
scsi target1:0:0: asynchronous
scsi1:A:0:0: Tagged Queuing enabled.  Depth 32
scsi target1:0:0: Beginning Domain Validation
scsi target1:0:0: wide asynchronous
scsi target1:0:0: FAST-160 WIDE SCSI 320.0 MB/s DT IU QAS RDSTRM WRFLOW PCOMP (6.25 ns, offset 63)
scsi target1:0:0: Ending Domain Validation
scsi 1:0:1:0: Direct-Access     SEAGATE  ST336807LW       0C01 PQ: 0 ANSI: 3
scsi target1:0:1: asynchronous
scsi1:A:1:0: Tagged Queuing enabled.  Depth 32
scsi target1:0:1: Beginning Domain Validation
scsi target1:0:1: wide asynchronous
scsi target1:0:1: FAST-160 WIDE SCSI 320.0 MB/s DT IU QAS RDSTRM WRFLOW PCOMP (6.25 ns, offset 63)
scsi target1:0:1: Ending Domain Validation
Driver 'sd' needs updating - please use bus_type methods
sd 1:0:0:0: [sda] 71687372 512-byte hardware sectors (36704 MB)
sd 1:0:0:0: [sda] Write Protect is off
sd 1:0:0:0: [sda] Mode Sense: ab 00 10 08
sd 1:0:0:0: [sda] Write cache: enabled, read cache: enabled, supports DPO and FUA
sd 1:0:0:0: [sda] 71687372 512-byte hardware sectors (36704 MB)
sd 1:0:0:0: [sda] Write Protect is off
sd 1:0:0:0: [sda] Mode Sense: ab 00 10 08
sd 1:0:0:0: [sda] Write cache: enabled, read cache: enabled, supports DPO and FUA
 sda: sda1 sda2
sd 1:0:0:0: [sda] Attached SCSI disk
sd 1:0:1:0: [sdb] 71687372 512-byte hardware sectors (36704 MB)
sd 1:0:1:0: [sdb] Write Protect is off
sd 1:0:1:0: [sdb] Mode Sense: ab 00 10 08
sd 1:0:1:0: [sdb] Write cache: enabled, read cache: enabled, supports DPO and FUA
sd 1:0:1:0: [sdb] 71687372 512-byte hardware sectors (36704 MB)
sd 1:0:1:0: [sdb] Write Protect is off
sd 1:0:1:0: [sdb] Mode Sense: ab 00 10 08
sd 1:0:1:0: [sdb] Write cache: enabled, read cache: enabled, supports DPO and FUA
 sdb: sdb1
sd 1:0:1:0: [sdb] Attached SCSI disk

-- 
J.A. Magallon <jamagallon()ono!com>     \               Software is like sex:
                                         \         It's better when it's free
Mandriva Linux release 2008.1 (Cooker) for i586
Linux 2.6.23-jam05 (gcc 4.2.2 20071128 (4.2.2-2mdv2008.1)) SMP PREEMPT

Re: Problems with -git14

[Hugh Dickins]

[-- Attachment #1: Type: TEXT/PLAIN, Size: 392 bytes --]

On Wed, 30 Apr 2008, J.A. Magallón wrote:
> > > 
> > > (dual Xeon HT)
...
> 
> One question that always bugs me: do I have to set NR_CPUS=8 to pick
> apicid number 7, and let the map just flag the ones I have,

No, that would be unbearable (few understand the logic of those ids).

> or will it work with NR_CPUS=4 ?

Yes, that works (and it's intended to work that way).

Hugh

Re: Problems with -git14

[Hugh Dickins]

[-- Attachment #1: Type: TEXT/PLAIN, Size: 6473 bytes --]

On Thu, 1 May 2008, J.A. Magallón wrote:
> On Wed, 30 Apr 2008 16:17:46 +0100 (BST), Hugh Dickins <hugh@veritas.com> wrote:
> > On Wed, 30 Apr 2008, J.A. Magallón wrote:
> > > 
> > > I have a couple problems with latest git (-14):
> > > 
> > > - It only recognises 2 processors out of 4 (dual Xeon HT)
> > > - It oopses on the swapper process just on boot...
> > > 
> > > Difference in dmesg is below. If full correct dmesg or config is
> > > needed, please ask for them. The kernel was built copying old
> > > 2.6.25 config to .config && make oldconfig. I filled the missing
> > > gaps like PAT and others...
...
> > > +WARNING: at include/linux/blkdev.h:427 blk_queue_init_tags+0x110/0x11f()
> > 
> > I presume this warning and backtrace is what you report as an oops:
> > I think you'll find Linus included a fix for this one overnight, and
> > it should have gone away in 2.6.25-git15 (but I didn't see it myself).
> 
> -git16 plus your patch gives me my 4 cpus again.

I'm glad to hear this, thanks.

> But I still get the warning:

But sorry to hear this.  That warning has undergone several revisions
already: I expect yours is another false positive not to worry about,
but it still needs to be fixed.  I won't meddle in there, Cc'ed Jens
and Nick who will know what's appropriate.

Hugh

> 
> scsi0 : Adaptec AIC79XX PCI-X SCSI HBA DRIVER, Rev 3.0
>         <Adaptec 29320 Ultra320 SCSI adapter>
>         aic7902: Ultra320 Wide Channel A, SCSI Id=7, PCI 33 or 66Mhz, 512 SCBs
> ACPI: PCI Interrupt 0000:03:0a.1[B] -> GSI 23 (level, low) -> IRQ 23
> scsi1 : Adaptec AIC79XX PCI-X SCSI HBA DRIVER, Rev 3.0
>         <Adaptec 29320 Ultra320 SCSI adapter>
>         aic7902: Ultra320 Wide Channel B, SCSI Id=7, PCI 33 or 66Mhz, 512 SCBs
> scsi 1:0:0:0: Direct-Access     SEAGATE  ST336807LW       0C01 PQ: 0 ANSI: 3
> ------------[ cut here ]------------
> WARNING: at include/linux/blkdev.h:431 blk_queue_init_tags+0x110/0x11f()
> Modules linked in:
> Pid: 1, comm: swapper Not tainted 2.6.25-jam03 #1
>  [<c011e618>] warn_on_slowpath+0x4d/0x66
>  [<c0132e68>] __atomic_notifier_call_chain+0x27/0x48
>  [<c0132ea0>] atomic_notifier_call_chain+0x17/0x1b
>  [<c024a7be>] notify_update+0x1f/0x23
>  [<c024aa07>] vt_console_print+0x1dd/0x2ab
>  [<c024a82a>] vt_console_print+0x0/0x2ab
>  [<c0132a2e>] up+0x9/0x2b
>  [<c01f314c>] init_tag_map+0x4e/0x95
>  [<c01f3271>] __blk_queue_init_tags+0x27/0x4e
>  [<c01f33a8>] blk_queue_init_tags+0x110/0x11f
>  [<c0285b9b>] ahd_platform_set_tags+0x177/0x1a7
>  [<c0286247>] ahd_linux_slave_configure+0xcd/0x131
>  [<c025e89e>] scsi_probe_and_add_lun+0x706/0x964
>  [<c025ecc7>] __scsi_scan_target+0xd9/0x5d9
>  [<c019ce63>] sysfs_ilookup_test+0x0/0xd
>  [<c019d8ea>] sysfs_addrm_finish+0x14/0x1c7
>  [<c019d16d>] sysfs_find_dirent+0x1e/0x27
>  [<c019d1b1>] sysfs_add_one+0x3b/0x8b
>  [<c019ccfc>] sysfs_add_file_mode+0x4d/0x76
>  [<c019e4cc>] internal_create_group+0xd7/0x196
>  [<c032a1b2>] klist_next+0x53/0x90
>  [<c025f23f>] scsi_scan_channel+0x78/0x8d
>  [<c025f2fc>] scsi_scan_host_selected+0xa8/0xd1
>  [<c025f38d>] do_scsi_scan_host+0x68/0x6a
>  [<c028540c>] ahd_linux_register_host+0x267/0x2db
>  [<c0287a6f>] ahd_pci_map_int+0x2c/0x50
>  [<c0280d5a>] ahd_pci_config+0x533/0x824
>  [<c01fce96>] kobject_get+0xf/0x13
>  [<c0251635>] get_device+0xe/0x14
>  [<c0208da9>] pci_dev_get+0xf/0x13
>  [<c0287c36>] ahd_linux_pci_dev_probe+0x139/0x17f
>  [<c019d8ea>] sysfs_addrm_finish+0x14/0x1c7
>  [<c019d16d>] sysfs_find_dirent+0x1e/0x27
>  [<c019d1b1>] sysfs_add_one+0x3b/0x8b
>  [<c019de53>] sysfs_create_link+0x89/0x106
>  [<c0209049>] pci_match_device+0x9c/0xad
>  [<c02090b0>] pci_device_probe+0x40/0x60
>  [<c0253b73>] driver_probe_device+0x76/0x152
>  [<c0253ca5>] __driver_attach+0x56/0x58
>  [<c02535ad>] bus_for_each_dev+0x39/0x57
>  [<c0209070>] pci_device_probe+0x0/0x60
>  [<c0253a36>] driver_attach+0x16/0x1a
>  [<c0253c4f>] __driver_attach+0x0/0x58
>  [<c02530ba>] bus_add_driver+0x19c/0x214
>  [<c0208d64>] pci_device_remove+0x0/0x36
>  [<c0209070>] pci_device_probe+0x0/0x60
>  [<c0253dc4>] driver_register+0x3b/0xd3
>  [<c0208f7b>] __pci_register_driver+0x32/0x64
>  [<c041abff>] ahd_linux_init+0x53/0x6f
>  [<c0406a36>] kernel_init+0x11d/0x287
>  [<c01174c2>] finish_task_switch+0x1f/0x6d
>  [<c0117711>] schedule_tail+0x16/0x44
>  [<c0102c62>] ret_from_fork+0x6/0x1c
>  [<c0406919>] kernel_init+0x0/0x287
>  [<c0406919>] kernel_init+0x0/0x287
>  [<c010393f>] kernel_thread_helper+0x7/0x18
>  =======================
> ---[ end trace e7ca32af98aeff40 ]---
> scsi target1:0:0: asynchronous
> scsi1:A:0:0: Tagged Queuing enabled.  Depth 32
> scsi target1:0:0: Beginning Domain Validation
> scsi target1:0:0: wide asynchronous
> scsi target1:0:0: FAST-160 WIDE SCSI 320.0 MB/s DT IU QAS RDSTRM WRFLOW PCOMP (6.25 ns, offset 63)
> scsi target1:0:0: Ending Domain Validation
> scsi 1:0:1:0: Direct-Access     SEAGATE  ST336807LW       0C01 PQ: 0 ANSI: 3
> scsi target1:0:1: asynchronous
> scsi1:A:1:0: Tagged Queuing enabled.  Depth 32
> scsi target1:0:1: Beginning Domain Validation
> scsi target1:0:1: wide asynchronous
> scsi target1:0:1: FAST-160 WIDE SCSI 320.0 MB/s DT IU QAS RDSTRM WRFLOW PCOMP (6.25 ns, offset 63)
> scsi target1:0:1: Ending Domain Validation
> Driver 'sd' needs updating - please use bus_type methods
> sd 1:0:0:0: [sda] 71687372 512-byte hardware sectors (36704 MB)
> sd 1:0:0:0: [sda] Write Protect is off
> sd 1:0:0:0: [sda] Mode Sense: ab 00 10 08
> sd 1:0:0:0: [sda] Write cache: enabled, read cache: enabled, supports DPO and FUA
> sd 1:0:0:0: [sda] 71687372 512-byte hardware sectors (36704 MB)
> sd 1:0:0:0: [sda] Write Protect is off
> sd 1:0:0:0: [sda] Mode Sense: ab 00 10 08
> sd 1:0:0:0: [sda] Write cache: enabled, read cache: enabled, supports DPO and FUA
>  sda: sda1 sda2
> sd 1:0:0:0: [sda] Attached SCSI disk
> sd 1:0:1:0: [sdb] 71687372 512-byte hardware sectors (36704 MB)
> sd 1:0:1:0: [sdb] Write Protect is off
> sd 1:0:1:0: [sdb] Mode Sense: ab 00 10 08
> sd 1:0:1:0: [sdb] Write cache: enabled, read cache: enabled, supports DPO and FUA
> sd 1:0:1:0: [sdb] 71687372 512-byte hardware sectors (36704 MB)
> sd 1:0:1:0: [sdb] Write Protect is off
> sd 1:0:1:0: [sdb] Mode Sense: ab 00 10 08
> sd 1:0:1:0: [sdb] Write cache: enabled, read cache: enabled, supports DPO and FUA
>  sdb: sdb1
> sd 1:0:1:0: [sdb] Attached SCSI disk

Re: Problems with -git14

[Nick Piggin]

On Thu, May 01, 2008 at 01:11:51PM +0100, Hugh Dickins wrote:
> On Thu, 1 May 2008, J.A. Magallón wrote:
> > On Wed, 30 Apr 2008 16:17:46 +0100 (BST), Hugh Dickins <hugh@veritas.com> wrote:
> > > On Wed, 30 Apr 2008, J.A. Magallón wrote:
> > > > 
> > > > I have a couple problems with latest git (-14):
> > > > 
> > > > - It only recognises 2 processors out of 4 (dual Xeon HT)
> > > > - It oopses on the swapper process just on boot...
> > > > 
> > > > Difference in dmesg is below. If full correct dmesg or config is
> > > > needed, please ask for them. The kernel was built copying old
> > > > 2.6.25 config to .config && make oldconfig. I filled the missing
> > > > gaps like PAT and others...
> ...
> > > > +WARNING: at include/linux/blkdev.h:427 blk_queue_init_tags+0x110/0x11f()
> > > 
> > > I presume this warning and backtrace is what you report as an oops:
> > > I think you'll find Linus included a fix for this one overnight, and
> > > it should have gone away in 2.6.25-git15 (but I didn't see it myself).
> > 
> > -git16 plus your patch gives me my 4 cpus again.
> 
> I'm glad to hear this, thanks.
> 
> > But I still get the warning:
> 
> But sorry to hear this.  That warning has undergone several revisions
> already: I expect yours is another false positive not to worry about,
> but it still needs to be fixed.  I won't meddle in there, Cc'ed Jens
> and Nick who will know what's appropriate.

Thanks for the heads up Hugh. I think we're OK at this point because
we're running in allocation/setup code so there should be no concurrency
on queue_flags. I remember following this call chain and making this
conclusion (hopefully correct, Jens?)... however I don't know how I
concluded that the warning would not fire.



> 
> Hugh
> 
> > 
> > scsi0 : Adaptec AIC79XX PCI-X SCSI HBA DRIVER, Rev 3.0
> >         <Adaptec 29320 Ultra320 SCSI adapter>
> >         aic7902: Ultra320 Wide Channel A, SCSI Id=7, PCI 33 or 66Mhz, 512 SCBs
> > ACPI: PCI Interrupt 0000:03:0a.1[B] -> GSI 23 (level, low) -> IRQ 23
> > scsi1 : Adaptec AIC79XX PCI-X SCSI HBA DRIVER, Rev 3.0
> >         <Adaptec 29320 Ultra320 SCSI adapter>
> >         aic7902: Ultra320 Wide Channel B, SCSI Id=7, PCI 33 or 66Mhz, 512 SCBs
> > scsi 1:0:0:0: Direct-Access     SEAGATE  ST336807LW       0C01 PQ: 0 ANSI: 3
> > ------------[ cut here ]------------
> > WARNING: at include/linux/blkdev.h:431 blk_queue_init_tags+0x110/0x11f()
> > Modules linked in:
> > Pid: 1, comm: swapper Not tainted 2.6.25-jam03 #1
> >  [<c011e618>] warn_on_slowpath+0x4d/0x66
> >  [<c0132e68>] __atomic_notifier_call_chain+0x27/0x48
> >  [<c0132ea0>] atomic_notifier_call_chain+0x17/0x1b
> >  [<c024a7be>] notify_update+0x1f/0x23
> >  [<c024aa07>] vt_console_print+0x1dd/0x2ab
> >  [<c024a82a>] vt_console_print+0x0/0x2ab
> >  [<c0132a2e>] up+0x9/0x2b
> >  [<c01f314c>] init_tag_map+0x4e/0x95
> >  [<c01f3271>] __blk_queue_init_tags+0x27/0x4e
> >  [<c01f33a8>] blk_queue_init_tags+0x110/0x11f
> >  [<c0285b9b>] ahd_platform_set_tags+0x177/0x1a7
> >  [<c0286247>] ahd_linux_slave_configure+0xcd/0x131
> >  [<c025e89e>] scsi_probe_and_add_lun+0x706/0x964
> >  [<c025ecc7>] __scsi_scan_target+0xd9/0x5d9
> >  [<c019ce63>] sysfs_ilookup_test+0x0/0xd
> >  [<c019d8ea>] sysfs_addrm_finish+0x14/0x1c7
> >  [<c019d16d>] sysfs_find_dirent+0x1e/0x27
> >  [<c019d1b1>] sysfs_add_one+0x3b/0x8b
> >  [<c019ccfc>] sysfs_add_file_mode+0x4d/0x76
> >  [<c019e4cc>] internal_create_group+0xd7/0x196
> >  [<c032a1b2>] klist_next+0x53/0x90
> >  [<c025f23f>] scsi_scan_channel+0x78/0x8d
> >  [<c025f2fc>] scsi_scan_host_selected+0xa8/0xd1
> >  [<c025f38d>] do_scsi_scan_host+0x68/0x6a
> >  [<c028540c>] ahd_linux_register_host+0x267/0x2db
> >  [<c0287a6f>] ahd_pci_map_int+0x2c/0x50
> >  [<c0280d5a>] ahd_pci_config+0x533/0x824
> >  [<c01fce96>] kobject_get+0xf/0x13
> >  [<c0251635>] get_device+0xe/0x14
> >  [<c0208da9>] pci_dev_get+0xf/0x13
> >  [<c0287c36>] ahd_linux_pci_dev_probe+0x139/0x17f
> >  [<c019d8ea>] sysfs_addrm_finish+0x14/0x1c7
> >  [<c019d16d>] sysfs_find_dirent+0x1e/0x27
> >  [<c019d1b1>] sysfs_add_one+0x3b/0x8b
> >  [<c019de53>] sysfs_create_link+0x89/0x106
> >  [<c0209049>] pci_match_device+0x9c/0xad
> >  [<c02090b0>] pci_device_probe+0x40/0x60
> >  [<c0253b73>] driver_probe_device+0x76/0x152
> >  [<c0253ca5>] __driver_attach+0x56/0x58
> >  [<c02535ad>] bus_for_each_dev+0x39/0x57
> >  [<c0209070>] pci_device_probe+0x0/0x60
> >  [<c0253a36>] driver_attach+0x16/0x1a
> >  [<c0253c4f>] __driver_attach+0x0/0x58
> >  [<c02530ba>] bus_add_driver+0x19c/0x214
> >  [<c0208d64>] pci_device_remove+0x0/0x36
> >  [<c0209070>] pci_device_probe+0x0/0x60
> >  [<c0253dc4>] driver_register+0x3b/0xd3
> >  [<c0208f7b>] __pci_register_driver+0x32/0x64
> >  [<c041abff>] ahd_linux_init+0x53/0x6f
> >  [<c0406a36>] kernel_init+0x11d/0x287
> >  [<c01174c2>] finish_task_switch+0x1f/0x6d
> >  [<c0117711>] schedule_tail+0x16/0x44
> >  [<c0102c62>] ret_from_fork+0x6/0x1c
> >  [<c0406919>] kernel_init+0x0/0x287
> >  [<c0406919>] kernel_init+0x0/0x287
> >  [<c010393f>] kernel_thread_helper+0x7/0x18
> >  =======================
> > ---[ end trace e7ca32af98aeff40 ]---
> > scsi target1:0:0: asynchronous
> > scsi1:A:0:0: Tagged Queuing enabled.  Depth 32
> > scsi target1:0:0: Beginning Domain Validation
> > scsi target1:0:0: wide asynchronous
> > scsi target1:0:0: FAST-160 WIDE SCSI 320.0 MB/s DT IU QAS RDSTRM WRFLOW PCOMP (6.25 ns, offset 63)
> > scsi target1:0:0: Ending Domain Validation
> > scsi 1:0:1:0: Direct-Access     SEAGATE  ST336807LW       0C01 PQ: 0 ANSI: 3
> > scsi target1:0:1: asynchronous
> > scsi1:A:1:0: Tagged Queuing enabled.  Depth 32
> > scsi target1:0:1: Beginning Domain Validation
> > scsi target1:0:1: wide asynchronous
> > scsi target1:0:1: FAST-160 WIDE SCSI 320.0 MB/s DT IU QAS RDSTRM WRFLOW PCOMP (6.25 ns, offset 63)
> > scsi target1:0:1: Ending Domain Validation
> > Driver 'sd' needs updating - please use bus_type methods
> > sd 1:0:0:0: [sda] 71687372 512-byte hardware sectors (36704 MB)
> > sd 1:0:0:0: [sda] Write Protect is off
> > sd 1:0:0:0: [sda] Mode Sense: ab 00 10 08
> > sd 1:0:0:0: [sda] Write cache: enabled, read cache: enabled, supports DPO and FUA
> > sd 1:0:0:0: [sda] 71687372 512-byte hardware sectors (36704 MB)
> > sd 1:0:0:0: [sda] Write Protect is off
> > sd 1:0:0:0: [sda] Mode Sense: ab 00 10 08
> > sd 1:0:0:0: [sda] Write cache: enabled, read cache: enabled, supports DPO and FUA
> >  sda: sda1 sda2
> > sd 1:0:0:0: [sda] Attached SCSI disk
> > sd 1:0:1:0: [sdb] 71687372 512-byte hardware sectors (36704 MB)
> > sd 1:0:1:0: [sdb] Write Protect is off
> > sd 1:0:1:0: [sdb] Mode Sense: ab 00 10 08
> > sd 1:0:1:0: [sdb] Write cache: enabled, read cache: enabled, supports DPO and FUA
> > sd 1:0:1:0: [sdb] 71687372 512-byte hardware sectors (36704 MB)
> > sd 1:0:1:0: [sdb] Write Protect is off
> > sd 1:0:1:0: [sdb] Mode Sense: ab 00 10 08
> > sd 1:0:1:0: [sdb] Write cache: enabled, read cache: enabled, supports DPO and FUA
> >  sdb: sdb1
> > sd 1:0:1:0: [sdb] Attached SCSI disk

Re: Problems with -git14

[Andrey Panin]

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On 121, 04 30, 2008 at 12:54:21PM -0300, Glauber Costa wrote:
> Hugh Dickins wrote:
>> On Wed, 30 Apr 2008, J.A. Magall??n wrote:
>>> I have a couple problems with latest git (-14):
>>>
>>> - It only recognises 2 processors out of 4 (dual Xeon HT)
>>> - It oopses on the swapper process just on boot...
>>>
>>> Difference in dmesg is below. If full correct dmesg or config is
>>> needed, please ask for them. The kernel was built copying old
>>> 2.6.25 config to .config && make oldconfig. I filled the missing
>>> gaps like PAT and others...
>>>
>>> -Brought up 4 CPUs
>>> +native_cpu_up: bad cpu 2
>>> +native_cpu_up: bad cpu 3
>>> +Brought up 2 CPUs
>>
>> Yes, I've been getting this for some days too: only 2 processors on
>> dual Xeon HT in 32-bit mode; whereas x86_64 finds all 4 just fine.
>> Ran lots of testing on 2.6.25-mm1 before I noticed it there.
>>
>> I bisected for a while, but it got confusing (arrived at a bisect
>> point which gave only 1 processor: smpboot code getting rearranged),
>> so I was forced (quel horreur!) to investigate properly.  I've just
>> now had success with the patch below, please give it a try:
>> but it'll need an Ack from Glauber before it can go in.
>>
>>> +WARNING: at include/linux/blkdev.h:427 blk_queue_init_tags+0x110/0x11f()
>>
>> I presume this warning and backtrace is what you report as an oops:
>> I think you'll find Linus included a fix for this one overnight, and
>> it should have gone away in 2.6.25-git15 (but I didn't see it myself).
>>
>> Hugh
>>
>> [PATCH] x86_32: fix HT cpu booting
>>
>> Since recent smpboot 32/64-bit merge, my dual Xeon with HT has been
>> booting only 2 of its 4 cpus (when running an i386 kernel; but x86_64
>> is okay).  J.A. Magall??n reports the same.
>>
>> native_cpu_up: bad cpu 2
>> native_cpu_up: bad cpu 3
>>
>> The mach-default cpu_present_to_apicid() was just returning cpu number
>> (2, 3) instead of apicid (6, 7): looks like we now need the x86_64 code
>> even for the i386 case.
>>
>> Comparing with other versions of cpu_present_to_apicid(), it seems a
>> good idea to include an NR_CPUS test too, since cpu_present() doesn't
>> include that; but that wasn't a problem here, and may no problem at all.
>>
>> One point worth noting - is it a worry?  Prior to that smpboot merge,
>> my Xeon booted the two HT siblings on one physical first, then the
>> two siblings on the other physical after - when i386, but alternated
>> them when x86_64.  Since the merge, the x86_64 sequence is unchanged,
>> but the i386 sequence is now like x86_64.  I prefer this consistency,
>> and I prefer the new sequence: booting with maxcpus=2 then uses the
>> independent physicals without HT sharing; but surprises in store?
>>
>> Signed-off-by: Hugh Dickins <hugh@veritas.com>
>>
>> --- 2.6.25-git/include/asm-x86/mach-default/mach_apic.h	2008-04-23 07:24:16.000000000 +0100
>> +++ linux/include/asm-x86/mach-default/mach_apic.h	2008-04-30 14:55:14.000000000 +0100
>> @@ -109,13 +109,8 @@ static inline int cpu_to_logical_apicid(
>>   static inline int cpu_present_to_apicid(int mps_cpu)
>>  {
>> -#ifdef CONFIG_X86_64
>> -	if (cpu_present(mps_cpu))
>> +	if (mps_cpu < NR_CPUS && cpu_present(mps_cpu))
>>  		return (int)per_cpu(x86_bios_cpu_apicid, mps_cpu);
>> -#else
>> -	if (mps_cpu < get_physical_broadcast())
>> -		return  mps_cpu;
>> -#endif
>>  	else
>>  		return BAD_APICID;
>>  }
>
> Hugh, thanks for tracing this. The patch looks sane to me
>
> However, since this problem was raised, I'm still concerned that visws may 
> have the same problem, since it uses the same logic that i386 mach_default 
> used to. (and I did not touched, since x86_64 code went int o 
> mach_default).
>
> Could anyone with access to such hardware give it a try ?

Unfortunately, no. Visws port is in non-bootable state currently, 2.6.25 hangs
in calibrate_delay_direct() and I still do not know why :(

-- 
Andrey Panin		| Linux and UNIX system administrator
pazke@donpac.ru		| PGP key: wwwkeys.pgp.net

[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 189 bytes --]

Re: Problems with -git14

[Thomas Gleixner]

On Mon, 5 May 2008, Andrey Panin wrote:
> > However, since this problem was raised, I'm still concerned that visws may 
> > have the same problem, since it uses the same logic that i386 mach_default 
> > used to. (and I did not touched, since x86_64 code went int o 
> > mach_default).
> >
> > Could anyone with access to such hardware give it a try ?
> 
> Unfortunately, no. Visws port is in non-bootable state currently, 2.6.25 hangs
> in calibrate_delay_direct() and I still do not know why :(

What was the last kernel which booted on visws ?

Thanks,
	tglx

Re: Problems with -git14

[Jens Axboe]

On Fri, May 02 2008, Nick Piggin wrote:
> On Thu, May 01, 2008 at 01:11:51PM +0100, Hugh Dickins wrote:
> > On Thu, 1 May 2008, J.A. Magallón wrote:
> > > On Wed, 30 Apr 2008 16:17:46 +0100 (BST), Hugh Dickins <hugh@veritas.com> wrote:
> > > > On Wed, 30 Apr 2008, J.A. Magallón wrote:
> > > > > 
> > > > > I have a couple problems with latest git (-14):
> > > > > 
> > > > > - It only recognises 2 processors out of 4 (dual Xeon HT)
> > > > > - It oopses on the swapper process just on boot...
> > > > > 
> > > > > Difference in dmesg is below. If full correct dmesg or config is
> > > > > needed, please ask for them. The kernel was built copying old
> > > > > 2.6.25 config to .config && make oldconfig. I filled the missing
> > > > > gaps like PAT and others...
> > ...
> > > > > +WARNING: at include/linux/blkdev.h:427 blk_queue_init_tags+0x110/0x11f()
> > > > 
> > > > I presume this warning and backtrace is what you report as an oops:
> > > > I think you'll find Linus included a fix for this one overnight, and
> > > > it should have gone away in 2.6.25-git15 (but I didn't see it myself).
> > > 
> > > -git16 plus your patch gives me my 4 cpus again.
> > 
> > I'm glad to hear this, thanks.
> > 
> > > But I still get the warning:
> > 
> > But sorry to hear this.  That warning has undergone several revisions
> > already: I expect yours is another false positive not to worry about,
> > but it still needs to be fixed.  I won't meddle in there, Cc'ed Jens
> > and Nick who will know what's appropriate.
> 
> Thanks for the heads up Hugh. I think we're OK at this point because
> we're running in allocation/setup code so there should be no concurrency
> on queue_flags. I remember following this call chain and making this
> conclusion (hopefully correct, Jens?)... however I don't know how I
> concluded that the warning would not fire.

That's USUALLY correct, but not always. If blk_queue_init_tags() is
called for resizing depth, then it's a running queue and we should not
use _unlocked() for that. So basically they can all be _unlocked() due
to lack of concurrency at init time, but not this one:

        } else if (q->queue_tags) {
                rc = blk_queue_resize_tags(q, depth);
                if (rc)
                        return rc;
                queue_flag_set(QUEUE_FLAG_QUEUED, q);
                return 0;
        } ...

So if a driver ever re-calls blk_queue_init_tags() with a tag map
already set, then it needs to hold the queue lock.

-- 
Jens Axboe