This patch adds a new configuration option, which adds support for a new
early_param which gets checked in arch/x86/kernel/setup_{32,64}.c:setup_arch()
to decide wether OHCI-1394 FireWire controllers should be initialized and
enabled for physical DMA access to allow remote debugging of early problems
like issues ACPI or other subsystems which are executed very early.
If the config option is not enabled, no code is changed, and if the boot
paramenter is not given, no new code is executed, and independent of that,
all new code is freed after boot, so the config option can be even enabled
in standard, non-debug kernels.
With specialized tools, it is then possible to get debugging information
from machines which have no serial ports (notebooks) such as the printk
buffer contents, or any data which can be referenced from global pointers,
if it is stored below the 4GB limit and even memory dumps of of the physical
RAM region below the 4GB limit can be taken without any cooperation from the
CPU of the host, so the machine can be crashed early, it does not matter.
In the extreme, even kernel debuggers can be accessed in this way. I wrote
a small kgdb module and an accompanying gdb stub for FireWire which allows
to gdb to talk to kgdb using remote remory reads and writes over FireWire.
An version of the gdb stub fore FireWire is able to read all global data
from a system which is running a a normal kernel without any kernel debugger,
without any interruption or support of the system's CPU. That way, e.g. the
task struct and so on can be read and even manipulated when the physical DMA
access is granted.
A HOWTO is included in this patch, in Documentation/debugging-via-ohci1394.txt
and I've put a copy online at
ftp://ftp.suse.de/private/bk/firewire/docs/debugging-via-ohci1394.txt
It also has links to all the tools which are available to make use of it
another copy of it is online at:
ftp://ftp.suse.de/private/bk/firewire/kernel/ohci1394_dma_early-v2.diff
Signed-Off-By: Bernhard Kaindl <bk@suse.de>
Tested-By: Thomas Renninger <trenn@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6: (200 commits)
[SCSI] usbstorage: use last_sector_bug flag universally
[SCSI] libsas: abstract STP task status into a function
[SCSI] ultrastor: clean up inline asm warnings
[SCSI] aic7xxx: fix firmware build
[SCSI] aacraid: fib context lock for management ioctls
[SCSI] ch: remove forward declarations
[SCSI] ch: fix device minor number management bug
[SCSI] ch: handle class_device_create failure properly
[SCSI] NCR5380: fix section mismatch
[SCSI] sg: fix /proc/scsi/sg/devices when no SCSI devices
[SCSI] IB/iSER: add logical unit reset support
[SCSI] don't use __GFP_DMA for sense buffers if not required
[SCSI] use dynamically allocated sense buffer
[SCSI] scsi.h: add macro for enclosure bit of inquiry data
[SCSI] sd: add fix for devices with last sector access problems
[SCSI] fix pcmcia compile problem
[SCSI] aacraid: add Voodoo Lite class of cards.
[SCSI] aacraid: add new driver features flags
[SCSI] qla2xxx: Update version number to 8.02.00-k7.
[SCSI] qla2xxx: Issue correct MBC_INITIALIZE_FIRMWARE command.
...
This patch relaxes the default SCSI DMA alignment from 512 bytes to 4
bytes. I remember from previous discussions that usb and firewire have
sector size alignment requirements, so I upped their alignments in the
respective slave allocs.
The reason for doing this is so that we don't get such a huge amount of
copy overhead in bio_copy_user() for udev. (basically all inquiries it
issues can now be directly mapped).
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Torsten Kaiser wrote:
> Looking that calltrace upwards, it seems replacing the
> memset(dma->sglist,...) with sg_init_table(...) would fix the BUG_ON()
> as that inits the SG_MAGIC.
Tested-by: Torsten Kaiser <just.for.lkml@googlemail.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Not architecture specific code should not #include <asm/scatterlist.h>.
This patch therefore either replaces them with
#include <linux/scatterlist.h> or simply removes them if they were
unused.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
This patch removes dead code spotted by the Intel C Compiler.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Most drivers need to set length and offset as well, so may as well fold
those three lines into one.
Add sg_assign_page() for those two locations that only needed to set
the page, where the offset/length is set outside of the function context.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Commits
58b053e4ce ("Update arch/ to use sg helpers")
45711f1af6 ("[SG] Update drivers to use sg helpers")
fa05f1286b ("Update net/ to use sg helpers")
converted many files to use the scatter gather helpers without ensuring
that the necessary headerfile <linux/scatterlist> is included. This
happened to work for ia64, powerpc, sparc64 and x86 because they
happened to drag in that file via their <asm/dma-mapping.h>.
On most of the others this probably broke.
Instead of increasing the header file spider web I choose to include
<linux/scatterlist.h> directly into the affectes files.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
drivers/ieee1394/ieee1394_core.c: Define spinlock using
DEFINE_SPINLOCK instead of assignment to SPIN_LOCK_UNLOCKED
Signed-off-by: Matthias Kaehlcke <matthias.kaehlcke@gmail.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
At least since nodemgr got rid of coarse global locking, accesses to
struct csr1212_keyval's reference counter should be atomic and coupled
with proper barriers. Also, calls to csr1212_keep_keyval(kv) should
occur before kv is being used.
(We probably should convert refcnt to struct kref, but how to keep
csr1212_destroy_keyval's implementation non-recursively then?)
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
csr1212_keep_keyval(kv) in nodemgr_process_root_directory was
unbalanced if ne->vendor_name_kv already exists. This happens for
example if eth1394 or raw1394 modify the local config ROM and it is
parsed again.
As a bonus, the attempt to add the vendor_name_kv sysfs attribute
when it already exists is now fixed for good.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
* Delete optional and empty i2c client_register and client_unregister
callbacks.
* Use the proper i2c adapter ID.
* Don't use a template to initialize the i2c_adapter structure, it's
inefficient.
* Update a misleading comment on why we use i2c_transfer rather than
higher level i2c functions.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
The nodemgr host thread can exit on its own even when kthread_should_stop
is not true, on receiving a signal (might never happen in practice, as
it ignores signals). But considering kthread_stop() must not be mixed with
kthreads that can exit on their own, I think changing the code like this
is clearer. This change means the thread can cut its sleep short when
receive a signal but looking at the code around, that sounds okay (and
again, it might never actually recieve a signal in practice).
Signed-off-by: Satyam Sharma <satyam@infradead.org>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
sbp2_host_reset and sbp2_handle_status_write are not serialized against
sbp2_alloc_device and sbp2_remove_device.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
This changes the uevent buffer functions to use a struct instead of a
long list of parameters. It does no longer require the caller to do the
proper buffer termination and size accounting, which is currently wrong
in some places. It fixes a known bug where parts of the uevent
environment are overwritten because of wrong index calculations.
Many thanks to Mathieu Desnoyers for finding bugs and improving the
error handling.
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Since hardware header operations are part of the protocol class
not the device instance, make them into a separate object and
save memory.
Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Wrap the hard_header_parse function to simplify next step of
header_ops conversion.
Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
It's been a useless no-op for long enough in 2.6 so I figured it's time to
remove it. The number of people that could object because they're
maintaining unified 2.4 and 2.6 drivers is probably rather small.
[ Handled drivers added by netdev tree and some missed IRDA cases... -DaveM ]
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Initialization of ohci1394 was broken according to one reporter if the
driver was statically linked, i.e. not built as loadable module. Dmesg:
PCI: Device 0000:02:07.0 not available because of resource collisions
ohci1394: Failed to enable OHCI hardware.
This was reported for a Toshiba Satellite 5100-503. The cause is commit
8df4083c52 in Linux 2.6.19-rc1 which only
served purposes of early remote debugging via FireWire. This
functionality is better provided by the currently out-of-tree driver
ohci1394_earlyinit. Reversal of the commit was OK'd by Andi Kleen.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Bug found by Olaf Hering <olh@suse.de>:
sbp2util_remove_command_orb_pool requires a valid lu->hi pointer.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Bernhard Kaindl
Linus Torvalds
Dave Young
James Bottomley
Jens Axboe
Adrian Bunk
Ralf Baechle
Matthias Kaehlcke
Stefan Richter
Jean Delvare
Satyam Sharma
Kay Sievers
Stephen Hemminger