Skip to content

Commit

Permalink
Merge git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-x86
Browse files Browse the repository at this point in the history
* git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-x86: (890 commits)
  x86: fix nodemap_size according to nodeid bits
  x86: fix overlap between pagetable with bss section
  x86: add PCI IDs to k8topology_64.c
  x86: fix early_ioremap pagetable ops
  x86: use the same pgd_list for PAE and 64-bit
  x86: defer cr3 reload when doing pud_clear()
  x86: early boot debugging via FireWire (ohci1394_dma=early)
  x86: don't special-case pmd allocations as much
  x86: shrink some ifdefs in fault.c
  x86: ignore spurious faults
  x86: remove nx_enabled from fault.c
  x86: unify fault_32|64.c
  x86: unify fault_32|64.c with ifdefs
  x86: unify fault_32|64.c by ifdef'd function bodies
  x86: arch/x86/mm/init_32.c printk fixes
  x86: arch/x86/mm/init_32.c cleanup
  x86: arch/x86/mm/init_64.c printk fixes
  x86: unify ioremap
  x86: fixes some bugs about EFI memory map handling
  x86: use reboot_type on EFI 32
  ...
  • Loading branch information
Linus Torvalds committed Jan 30, 2008
2 parents 60e2331 + afadcd7 commit dd430ca
Show file tree
Hide file tree
Showing 635 changed files with 36,226 additions and 36,994 deletions.
179 changes: 179 additions & 0 deletions Documentation/debugging-via-ohci1394.txt
Original file line number Diff line number Diff line change
@@ -0,0 +1,179 @@

Using physical DMA provided by OHCI-1394 FireWire controllers for debugging
---------------------------------------------------------------------------

Introduction
------------

Basically all FireWire controllers which are in use today are compliant
to the OHCI-1394 specification which defines the controller to be a PCI
bus master which uses DMA to offload data transfers from the CPU and has
a "Physical Response Unit" which executes specific requests by employing
PCI-Bus master DMA after applying filters defined by the OHCI-1394 driver.

Once properly configured, remote machines can send these requests to
ask the OHCI-1394 controller to perform read and write requests on
physical system memory and, for read requests, send the result of
the physical memory read back to the requester.

With that, it is possible to debug issues by reading interesting memory
locations such as buffers like the printk buffer or the process table.

Retrieving a full system memory dump is also possible over the FireWire,
using data transfer rates in the order of 10MB/s or more.

Memory access is currently limited to the low 4G of physical address
space which can be a problem on IA64 machines where memory is located
mostly above that limit, but it is rarely a problem on more common
hardware such as hardware based on x86, x86-64 and PowerPC.

Together with a early initialization of the OHCI-1394 controller for debugging,
this facility proved most useful for examining long debugs logs in the printk
buffer on to debug early boot problems in areas like ACPI where the system
fails to boot and other means for debugging (serial port) are either not
available (notebooks) or too slow for extensive debug information (like ACPI).

Drivers
-------

The OHCI-1394 drivers in drivers/firewire and drivers/ieee1394 initialize
the OHCI-1394 controllers to a working state and can be used to enable
physical DMA. By default you only have to load the driver, and physical
DMA access will be granted to all remote nodes, but it can be turned off
when using the ohci1394 driver.

Because these drivers depend on the PCI enumeration to be completed, an
initialization routine which can runs pretty early (long before console_init(),
which makes the printk buffer appear on the console can be called) was written.

To activate it, enable CONFIG_PROVIDE_OHCI1394_DMA_INIT (Kernel hacking menu:
Provide code for enabling DMA over FireWire early on boot) and pass the
parameter "ohci1394_dma=early" to the recompiled kernel on boot.

Tools
-----

firescope - Originally developed by Benjamin Herrenschmidt, Andi Kleen ported
it from PowerPC to x86 and x86_64 and added functionality, firescope can now
be used to view the printk buffer of a remote machine, even with live update.

Bernhard Kaindl enhanced firescope to support accessing 64-bit machines
from 32-bit firescope and vice versa:
- ftp://ftp.suse.de/private/bk/firewire/tools/firescope-0.2.2.tar.bz2

and he implemented fast system dump (alpha version - read README.txt):
- ftp://ftp.suse.de/private/bk/firewire/tools/firedump-0.1.tar.bz2

There is also a gdb proxy for firewire which allows to use gdb to access
data which can be referenced from symbols found by gdb in vmlinux:
- ftp://ftp.suse.de/private/bk/firewire/tools/fireproxy-0.33.tar.bz2

The latest version of this gdb proxy (fireproxy-0.34) can communicate (not
yet stable) with kgdb over an memory-based communication module (kgdbom).

Getting Started
---------------

The OHCI-1394 specification regulates that the OHCI-1394 controller must
disable all physical DMA on each bus reset.

This means that if you want to debug an issue in a system state where
interrupts are disabled and where no polling of the OHCI-1394 controller
for bus resets takes place, you have to establish any FireWire cable
connections and fully initialize all FireWire hardware __before__ the
system enters such state.

Step-by-step instructions for using firescope with early OHCI initialization:

1) Verify that your hardware is supported:

Load the ohci1394 or the fw-ohci module and check your kernel logs.
You should see a line similar to

ohci1394: fw-host0: OHCI-1394 1.1 (PCI): IRQ=[18] MMIO=[fe9ff800-fe9fffff]
... Max Packet=[2048] IR/IT contexts=[4/8]

when loading the driver. If you have no supported controller, many PCI,
CardBus and even some Express cards which are fully compliant to OHCI-1394
specification are available. If it requires no driver for Windows operating
systems, it most likely is. Only specialized shops have cards which are not
compliant, they are based on TI PCILynx chips and require drivers for Win-
dows operating systems.

2) Establish a working FireWire cable connection:

Any FireWire cable, as long at it provides electrically and mechanically
stable connection and has matching connectors (there are small 4-pin and
large 6-pin FireWire ports) will do.

If an driver is running on both machines you should see a line like

ieee1394: Node added: ID:BUS[0-01:1023] GUID[0090270001b84bba]

on both machines in the kernel log when the cable is plugged in
and connects the two machines.

3) Test physical DMA using firescope:

On the debug host,
- load the raw1394 module,
- make sure that /dev/raw1394 is accessible,
then start firescope:

$ firescope
Port 0 (ohci1394) opened, 2 nodes detected

FireScope
---------
Target : <unspecified>
Gen : 1
[Ctrl-T] choose target
[Ctrl-H] this menu
[Ctrl-Q] quit

------> Press Ctrl-T now, the output should be similar to:

2 nodes available, local node is: 0
0: ffc0, uuid: 00000000 00000000 [LOCAL]
1: ffc1, uuid: 00279000 ba4bb801

Besides the [LOCAL] node, it must show another node without error message.

4) Prepare for debugging with early OHCI-1394 initialization:

4.1) Kernel compilation and installation on debug target

Compile the kernel to be debugged with CONFIG_PROVIDE_OHCI1394_DMA_INIT
(Kernel hacking: Provide code for enabling DMA over FireWire early on boot)
enabled and install it on the machine to be debugged (debug target).

4.2) Transfer the System.map of the debugged kernel to the debug host

Copy the System.map of the kernel be debugged to the debug host (the host
which is connected to the debugged machine over the FireWire cable).

5) Retrieving the printk buffer contents:

With the FireWire cable connected, the OHCI-1394 driver on the debugging
host loaded, reboot the debugged machine, booting the kernel which has
CONFIG_PROVIDE_OHCI1394_DMA_INIT enabled, with the option ohci1394_dma=early.

Then, on the debugging host, run firescope, for example by using -A:

firescope -A System.map-of-debug-target-kernel

Note: -A automatically attaches to the first non-local node. It only works
reliably if only connected two machines are connected using FireWire.

After having attached to the debug target, press Ctrl-D to view the
complete printk buffer or Ctrl-U to enter auto update mode and get an
updated live view of recent kernel messages logged on the debug target.

Call "firescope -h" to get more information on firescope's options.

Notes
-----
Documentation and specifications: ftp://ftp.suse.de/private/bk/firewire/docs

FireWire is a trademark of Apple Inc. - for more information please refer to:
http://en.wikipedia.org/wiki/FireWire
51 changes: 49 additions & 2 deletions Documentation/kernel-parameters.txt
Original file line number Diff line number Diff line change
Expand Up @@ -416,8 +416,21 @@ and is between 256 and 4096 characters. It is defined in the file
[SPARC64] tick
[X86-64] hpet,tsc

code_bytes [IA32] How many bytes of object code to print in an
oops report.
clearcpuid=BITNUM [X86]
Disable CPUID feature X for the kernel. See
include/asm-x86/cpufeature.h for the valid bit numbers.
Note the Linux specific bits are not necessarily
stable over kernel options, but the vendor specific
ones should be.
Also note that user programs calling CPUID directly
or using the feature without checking anything
will still see it. This just prevents it from
being used by the kernel or shown in /proc/cpuinfo.
Also note the kernel might malfunction if you disable
some critical bits.

code_bytes [IA32/X86_64] How many bytes of object code to print
in an oops report.
Range: 0 - 8192
Default: 64

Expand Down Expand Up @@ -570,6 +583,12 @@ and is between 256 and 4096 characters. It is defined in the file
See drivers/char/README.epca and
Documentation/digiepca.txt.

disable_mtrr_trim [X86, Intel and AMD only]
By default the kernel will trim any uncacheable
memory out of your available memory pool based on
MTRR settings. This parameter disables that behavior,
possibly causing your machine to run very slowly.

dmasound= [HW,OSS] Sound subsystem buffers

dscc4.setup= [NET]
Expand Down Expand Up @@ -660,6 +679,10 @@ and is between 256 and 4096 characters. It is defined in the file

gamma= [HW,DRM]

gart_fix_e820= [X86_64] disable the fix e820 for K8 GART
Format: off | on
default: on

gdth= [HW,SCSI]
See header of drivers/scsi/gdth.c.

Expand Down Expand Up @@ -794,6 +817,16 @@ and is between 256 and 4096 characters. It is defined in the file
for translation below 32 bit and if not available
then look in the higher range.

io_delay= [X86-32,X86-64] I/O delay method
0x80
Standard port 0x80 based delay
0xed
Alternate port 0xed based delay (needed on some systems)
udelay
Simple two microseconds delay
none
No delay

io7= [HW] IO7 for Marvel based alpha systems
See comment before marvel_specify_io7 in
arch/alpha/kernel/core_marvel.c.
Expand Down Expand Up @@ -1059,6 +1092,11 @@ and is between 256 and 4096 characters. It is defined in the file
Multi-Function General Purpose Timers on AMD Geode
platforms.

mfgptfix [X86-32] Fix MFGPT timers on AMD Geode platforms when
the BIOS has incorrectly applied a workaround. TinyBIOS
version 0.98 is known to be affected, 0.99 fixes the
problem by letting the user disable the workaround.

mga= [HW,DRM]

mousedev.tap_time=
Expand Down Expand Up @@ -1159,6 +1197,8 @@ and is between 256 and 4096 characters. It is defined in the file

nodisconnect [HW,SCSI,M68K] Disables SCSI disconnects.

noefi [X86-32,X86-64] Disable EFI runtime services support.

noexec [IA-64]

noexec [X86-32,X86-64]
Expand All @@ -1169,6 +1209,8 @@ and is between 256 and 4096 characters. It is defined in the file
register save and restore. The kernel will only save
legacy floating-point registers on task switch.

noclflush [BUGS=X86] Don't use the CLFLUSH instruction

nohlt [BUGS=ARM]

no-hlt [BUGS=X86-32] Tells the kernel that the hlt
Expand Down Expand Up @@ -1978,6 +2020,11 @@ and is between 256 and 4096 characters. It is defined in the file
vdso=1: enable VDSO (default)
vdso=0: disable VDSO mapping

vdso32= [X86-32,X86-64]
vdso32=2: enable compat VDSO (default with COMPAT_VDSO)
vdso32=1: enable 32-bit VDSO (default)
vdso32=0: disable 32-bit VDSO mapping

vector= [IA-64,SMP]
vector=percpu: enable percpu vector domain

Expand Down
8 changes: 7 additions & 1 deletion Documentation/x86_64/boot-options.txt
Original file line number Diff line number Diff line change
Expand Up @@ -110,12 +110,18 @@ Idle loop

Rebooting

reboot=b[ios] | t[riple] | k[bd] [, [w]arm | [c]old]
reboot=b[ios] | t[riple] | k[bd] | a[cpi] | e[fi] [, [w]arm | [c]old]
bios Use the CPU reboot vector for warm reset
warm Don't set the cold reboot flag
cold Set the cold reboot flag
triple Force a triple fault (init)
kbd Use the keyboard controller. cold reset (default)
acpi Use the ACPI RESET_REG in the FADT. If ACPI is not configured or the
ACPI reset does not work, the reboot path attempts the reset using
the keyboard controller.
efi Use efi reset_system runtime service. If EFI is not configured or the
EFI reset does not work, the reboot path attempts the reset using
the keyboard controller.

Using warm reset will be much faster especially on big memory
systems because the BIOS will not go through the memory check.
Expand Down
9 changes: 9 additions & 0 deletions Documentation/x86_64/uefi.txt
Original file line number Diff line number Diff line change
Expand Up @@ -19,6 +19,10 @@ Mechanics:
- Build the kernel with the following configuration.
CONFIG_FB_EFI=y
CONFIG_FRAMEBUFFER_CONSOLE=y
If EFI runtime services are expected, the following configuration should
be selected.
CONFIG_EFI=y
CONFIG_EFI_VARS=y or m # optional
- Create a VFAT partition on the disk
- Copy the following to the VFAT partition:
elilo bootloader with x86_64 support, elilo configuration file,
Expand All @@ -27,3 +31,8 @@ Mechanics:
can be found in the elilo sourceforge project.
- Boot to EFI shell and invoke elilo choosing the kernel image built
in first step.
- If some or all EFI runtime services don't work, you can try following
kernel command line parameters to turn off some or all EFI runtime
services.
noefi turn off all EFI runtime services
reboot_type=k turn off EFI reboot runtime service
5 changes: 5 additions & 0 deletions arch/arm/Kconfig
Original file line number Diff line number Diff line change
Expand Up @@ -91,6 +91,11 @@ config GENERIC_IRQ_PROBE
bool
default y

config GENERIC_LOCKBREAK
bool
default y
depends on SMP && PREEMPT

config RWSEM_GENERIC_SPINLOCK
bool
default y
Expand Down
8 changes: 8 additions & 0 deletions arch/ia64/Kconfig
Original file line number Diff line number Diff line change
Expand Up @@ -42,6 +42,11 @@ config MMU
config SWIOTLB
bool

config GENERIC_LOCKBREAK
bool
default y
depends on SMP && PREEMPT

config RWSEM_XCHGADD_ALGORITHM
bool
default y
Expand Down Expand Up @@ -75,6 +80,9 @@ config GENERIC_TIME_VSYSCALL
bool
default y

config ARCH_SETS_UP_PER_CPU_AREA
def_bool y

config DMI
bool
default y
Expand Down
3 changes: 2 additions & 1 deletion arch/ia64/ia32/binfmt_elf32.c
Original file line number Diff line number Diff line change
Expand Up @@ -222,7 +222,8 @@ elf32_set_personality (void)
}

static unsigned long
elf32_map (struct file *filep, unsigned long addr, struct elf_phdr *eppnt, int prot, int type)
elf32_map(struct file *filep, unsigned long addr, struct elf_phdr *eppnt,
int prot, int type, unsigned long unused)
{
unsigned long pgoff = (eppnt->p_vaddr) & ~IA32_PAGE_MASK;

Expand Down
2 changes: 1 addition & 1 deletion arch/ia64/kernel/module.c
Original file line number Diff line number Diff line change
Expand Up @@ -947,7 +947,7 @@ percpu_modcopy (void *pcpudst, const void *src, unsigned long size)
{
unsigned int i;
for_each_possible_cpu(i) {
memcpy(pcpudst + __per_cpu_offset[i], src, size);
memcpy(pcpudst + per_cpu_offset(i), src, size);
}
}
#endif /* CONFIG_SMP */
5 changes: 5 additions & 0 deletions arch/m32r/Kconfig
Original file line number Diff line number Diff line change
Expand Up @@ -235,6 +235,11 @@ config IRAM_SIZE
# Define implied options from the CPU selection here
#

config GENERIC_LOCKBREAK
bool
default y
depends on SMP && PREEMPT

config RWSEM_GENERIC_SPINLOCK
bool
depends on M32R
Expand Down
Loading

0 comments on commit dd430ca

Please sign in to comment.