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This patch adds support for the TQM8548 modules from TQ-Components
GmbH (http://www.tqc.de).
Signed-off-by: Wolfgang Grandegger <wg@grandegger.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
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Like for the TQM5200, the vendor prefix "tqc," is now used for all
TQM85xx modules from TQ-Components GmbH (http://www.tqc.de) in the
corresponding DTS files.
Signed-off-by: Wolfgang Grandegger <wg@grandegger.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
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All the maintained platforms are now in arch/powerpc, so the old
arch/ppc stuff can now go away.
Acked-by: Adrian Bunk <bunk@kernel.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Becky Bruce <becky.bruce@freescale.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Jochen Friedrich <jochen@scram.de>
Acked-by: John Linn <john.linn@xilinx.com>
Acked-by: Jon Loeliger <jdl@freescale.com>
Acked-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
Acked-by: Olof Johansson <olof@lixom.net>
Acked-by: Peter Korsgaard <jacmet@sunsite.dk>
Acked-by: Scott Wood <scottwood@freescale.com>
Acked-by: Sean MacLennan <smaclennan@pikatech.com>
Acked-by: Segher Boessenkool <segher@kernel.crashing.org>
Acked-by: Stefan Roese <sr@denx.de>
Acked-by: Stephen Neuendorffer <stephen.neuendorffer@xilinx.com>
Acked-by: Wolfgang Denk <wd@denx.de>
Signed-off-by: Paul Mackerras <paulus@samba.org>
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When I changed irq_alloc_host() to take an of_node
(52964f87c64e6c6ea671b5bf3030fb1494090a48: "Add an optional
device_node pointer to the irq_host"), I botched the reference
counting semantics.
Stephen pointed out that it's irq_alloc_host()'s business if
it needs to take an additional reference to the device_node,
the caller shouldn't need to care.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
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If we do the call to of_address_to_resource() first, then we don't
need to worry about freeing the irq_host (which the code doesn't do
currently anyway).
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
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If we do the call to of_address_to_resource() first, then we don't
need to worry about freeing the irq_host (which the code doesn't do
currently anyway).
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
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If we do the call to irq_of_parse_and_map() first, then we don't
need to worry about freeing the irq_host.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
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This eliminates this minor boot-time debugging error message:
[ 1.316451] calling add_pcspkr+0x0/0x84
[ 1.316478] initcall add_pcspkr+0x0/0x84 returned -19 after 0 msecs
Signed-off-by: Emil Medve <Emilian.Medve@Freescale.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
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Support for the C2K cPCI Single Board Computer from GEFanuc
(PowerPC MPC7448 with a Marvell MV64460 chipset).
All features of the board are not supported yet, but the board
boots, flash works, all Ethernet ports are working and PCI
devices are all found (USB and SATA on PCI1 do not work yet).
Part 5 of 5: add the Kconfig entry for the C2K board.
Signed-off-by: Remi Machet <rmachet@slac.stanford.edu>
Signed-off-by: Paul Mackerras <paulus@samba.org>
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Support for the C2K cPCI Single Board Computer from GEFanuc
(PowerPC MPC7448 with a Marvell MV64460 chipset).
All features of the board are not supported yet, but the board
boots, flash works, all Ethernet ports are working and PCI
devices are all found (USB and SATA on PCI1 do not work yet).
Part 4 of 5: this is the default config for the board. In this
configuration the kernel is going to try to boot from MTD
partition 3 on the NOR flash (see c2k.dts for details about
the partitioning of the flash).
Signed-off-by: Remi Machet <rmachet@slac.stanford.edu>
Signed-off-by: Paul Mackerras <paulus@samba.org>
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Support for the C2K cPCI Single Board Computer from GEFanuc
(PowerPC MPC7448 with a Marvell MV64460 chipset).
All features of the board are not supported yet, but the board
boots, flash works, all Ethernet ports are working and PCI
devices are all found (USB and SATA on PCI1 do not work yet).
Part 3 of 5: driver for the board. At this time it is very generic
and similar to its original, the driver for the prpmc2800.
Signed-off-by: Remi Machet <rmachet@slac.stanford.edu>
Signed-off-by: Paul Mackerras <paulus@samba.org>
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Support for the C2K cPCI Single Board Computer from GEFanuc
(PowerPC MPC7448 with a Marvell MV64460 chipset).
All features of the board are not supported yet, but the board
boots, flash works, all Ethernet ports are working and PCI
devices are all found (USB and SATA on PCI1 do not work yet).
Part 2 of 5: support for the board in arch/powerpc/boot.
Signed-off-by: Remi Machet <rmachet@slac.stanford.edu>
Signed-off-by: Paul Mackerras <paulus@samba.org>
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Support for the C2K cPCI Single Board Computer from GEFanuc
(PowerPC MPC7448 with a Marvell MV64460 chipset).
All features of the board are not supported yet, but the board
boots, flash works, all Ethernet ports are working and PCI
devices are all found (USB and SATA on PCI1 do not work yet).
Part 1 of 5: DTS file describing the board peripherals. As far as I
know all peripherals except the FPGA are listed in there (I did not
include the FPGA because a lot of work is needed there).
Signed-off-by: Remi Machet <rmachet@slac.stanford.edu>
Signed-off-by: Paul Mackerras <paulus@samba.org>
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This fixes the following warning, introduced by commit
475ca391b490a683d66bf19999a8a7a24913f139 (mpic: Deal with bogus NIRQ
in Feature Reporting Register):
CC arch/powerpc/sysdev/mpic.o
arch/powerpc/sysdev/mpic.c: In function 'mpic_alloc':
arch/powerpc/sysdev/mpic.c:1146: warning: suggest explicit braces to avoid ambiguous 'else'
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
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Conflicts:
arch/powerpc/sysdev/fsl_soc.c
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The ehea driver was recently changed[1] to use walk_memory_resource() to
detect the system's memory layout. However, walk_memory_resource() is
available only when memory hotplug is enabled. So CONFIG_EHEA was
made to depend on MEMORY_HOTPLUG [2], but it is inappropriate for a
network driver to have such a dependency.
Make the declaration of walk_memory_resource() and its powerpc
implementation (ehea is powerpc-specific) unconditionally available.
[1] 48cfb14f8b89d4d5b3df6c16f08b258686fb12ad
"ehea: Add DLPAR memory remove support"
[2] fb7b6ca2b6b7c23b52be143bdd5f55a23b9780c8
"ehea: Add dependency to Kconfig"
Signed-off-by: Nathan Lynch <ntl@pobox.com>
Acked-by: Badari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
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During the next merge window, pci_name()'s return value will become
const, so use the new dev_set_name() instead to avoid the warning (from
linux-next):
arch/powerpc/kernel/pci_64.c: In function 'of_create_pci_dev':
arch/powerpc/kernel/pci_64.c:193: warning: passing argument 1 of 'sprintf' discards qualifiers from pointer target type
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
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When building a signal or a ucontext, we can incorrectly set the MSR_VEC
bit of the kernel pt_regs->msr before returning to userspace if the task
-ever- used VMX.
This can lead to funny result if that stack used it in the past, then
"lost" it (ie. it wasn't enabled after a context switch for example)
and then called get_context. It can end up with VMX enabled and the
registers containing values from some other task.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
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This corrects the names of two CONFIG_ variables.
Note that the CONFIG_MPC86XADS fix uncovers another bug
(with mpc866_ads_defconfig) that will require fixing:
<-- snip -->
...
arch/powerpc/boot/dtc -O dtb -o arch/powerpc/boot/mpc866ads.dtb -b 0 /home/bunk/linux/kernel-2.6/git/linux-2.6/arch/powerpc/boot/dts/mpc866ads.dts
DTC: dts->dtb on file "/home/bunk/linux/kernel-2.6/git/linux-2.6/arch/powerpc/boot/dts/mpc866ads.dts"
WRAP arch/powerpc/boot/cuImage.mpc866ads
powerpc64-linux-ld: arch/powerpc/boot/cuboot-mpc866ads.o: No such file: No such file or directory
make[2]: *** [arch/powerpc/boot/cuImage.mpc866ads] Error 1
<-- snip -->
Reported-by: Robert P. J. Day <rpjday@crashcourse.ca>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6:
x86/PCI: add workaround for bug in ASUS A7V600 BIOS (rev 1005)
PCI/x86: fix up PCI stuff so that PCI_GOANY supports OLPC
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Change the name of the device from "rtc-ds1374" to just "ds1374", to match
what all other RTC drivers do. I seem to remember that this name was
chosen to avoid possible confusion with an older ds1374 driver, but that
driver was removed 3 months ago.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Alessandro Zummo <a.zummo@towertech.it>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Although if people have questions about ARCnet, perhaps it's _better_
for them to be mailing dwmw2@cam.ac.uk about it...
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Include limits.h to get a definition of PATH_MAX.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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We lost the marking of SIGWINCH as being OK to receive during stub
execution, causing a panic should that happen.
Cc: Benedict Verheyen <benedict.verheyen@gmail.com>
Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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x86_64 defines either memcpy or __memcpy depending on the gcc version, and
it looks like UML needs to follow that in its exporting.
Cc: Gabriel C <nix.or.die@googlemail.com>
Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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This patch makes os_get_task_size locate the bottom of the address space,
as well as the top. This is for systems which put a lower limit on mmap
addresses. It works by manually scanning pages from zero onwards until a
valid page is found.
Because the bottom of the address space may not be zero, it's not
sufficient to assume the top of the address space is the size of the
address space. The size is the difference between the top address and
bottom address.
[jdike@addtoit.com: changed the name to reflect that this function is
supposed to return the top of the process address space, not its size and
changed the return value to reflect that. Also some minor formatting
changes]
Signed-off-by: Tom Spink <tspink@gmail.com>
Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Removed duplicated include file "kern_util.h" in
arch/um/drivers/ubd_kern.c.
Signed-off-by: Huang Weiyi <weiyi.huang@gmail.com>
Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Protection against the host's time going backwards (eg, ntp activity on
the host) by keeping track of the time at the last tick and if it's
greater than the current time, keep time stopped until the host catches
up.
Cc: Nix <nix@esperi.org.uk>
Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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As some m68k machines have plenty of libc5 binaries in active use, enable
CONFIG_COMPAT_BRK by default.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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* master.kernel.org:/home/rmk/linux-2.6-arm:
[ARM] pxa: fix tosa.c build error
[ARM] 5067/1: _raw_write_can_lock macro bugfix
[ARM] 5070/1: pxa: add GPIO104_PSKTSEL to pxa27x MFP configuration
[ARM] 5068/1: PXA2xx Additional gpio definitions
[ARM] 5066/2: EM-X270: Fix DM9000 IRQ flags initialisation
[ARM] 5065/2: CM-X270: Fix DM9000 IRQ flags initialisation
[ARM] 5062/1: pxa: remove unused definition of CONFIG_ARCH_COTULLA_IDP
[ARM] 5060/1: remove unnecessary include of asm/io.h
[ARM] fix AT91 include loops
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This BIOS claims the VIA 8237 south bridge to be compatible with VIA 586,
which it is not.
Without this patch, I get the following warning while booting,
among others,
| PCI: Using IRQ router VIA [1106/3227] at 0000:00:11.0
| ------------[ cut here ]------------
| WARNING: at arch/x86/pci/irq.c:265 pirq_via586_get+0x4a/0x60()
| Modules linked in:
| Pid: 1, comm: swapper Not tainted 2.6.26-rc4-00015-g1ec7d99 #1
| [<c0119fd4>] warn_on_slowpath+0x54/0x70
| [<c02246e0>] ? vt_console_print+0x210/0x2b0
| [<c02244d0>] ? vt_console_print+0x0/0x2b0
| [<c011a413>] ? __call_console_drivers+0x43/0x60
| [<c011a482>] ? _call_console_drivers+0x52/0x80
| [<c011aa89>] ? release_console_sem+0x1c9/0x200
| [<c0291d21>] ? raw_pci_read+0x41/0x70
| [<c0291e8f>] ? pci_read+0x2f/0x40
| [<c029151a>] pirq_via586_get+0x4a/0x60
| [<c02914d0>] ? pirq_via586_get+0x0/0x60
| [<c029178d>] pcibios_lookup_irq+0x15d/0x430
| [<c03b895a>] pcibios_irq_init+0x17a/0x3e0
| [<c03a66f0>] ? kernel_init+0x0/0x250
| [<c03a6763>] kernel_init+0x73/0x250
| [<c03b87e0>] ? pcibios_irq_init+0x0/0x3e0
| [<c0114d00>] ? schedule_tail+0x10/0x40
| [<c0102dee>] ? ret_from_fork+0x6/0x1c
| [<c03a66f0>] ? kernel_init+0x0/0x250
| [<c03a66f0>] ? kernel_init+0x0/0x250
| [<c010324b>] kernel_thread_helper+0x7/0x1c
| =======================
| ---[ end trace 4eaa2a86a8e2da22 ]---
and IRQ trouble later,
| irq 10: nobody cared (try booting with the "irqpoll" option)
Now that's an VIA 8237 chip, so pirq_via586_get shouldn't be called
at all; adding this workaround to via_router_probe() fixes the
problem for me.
Amazingly I have a 2.6.23.8 kernel that somehow works fine ... I'll
never understand why.
Signed-off-by: Bertram Felgenhauer <int-e@gmx.de>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Acked-by: Alan Cox <alan@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
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* 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus:
Fix divide by zero error in build_clear_page() and build_copy_page()
[MIPS] Fix typo in header guard
[MIPS] Fix build error - Delete debugging crap that crept in with CMP
[MIPS] Add accessors for random register.
[MIPS] IP27: misc fixes
[MIPS] IP27: Fix clockevent setup
[MIPS] IP27: Fix bootmem memory setup
[MIPS] remove CONFIG_CPU_R4000 line from Makefile
[MIPS] Fix check for valid stack pointer during backtrace
[MIPS] Add missing braces to pte_mkyoung
[MIPS] R4700: Fix build_tlb_probe_entry
[MIPS] Alchemy: dbdma: add API to delete custom DDMA device ids.
[MIPS] Alchemy: export get_au1x00_speed for modules
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Previously, one would have to specifically choose CONFIG_OLPC and
CONFIG_PCI_GOOLPC in order to enable PCI_OLPC. That doesn't really work
for distro kernels, so this patch allows one to choose CONFIG_OLPC and
CONFIG_PCI_GOANY in order to build in OLPC support in a generic kernel (as
requested by Robert Millan).
This also moves GOOLPC before GOANY in the menuconfig list.
Finally, make pci_access_init return early if we detect OLPC hardware.
There's no need to continue probing stuff, and pci_pcbios_init
specifically trashes our settings (we didn't run into that before because
PCI_GOANY wasn't supported).
Signed-off-by: Andres Salomon <dilinger@debian.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
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Here is an attempt to translate the prompt and help text into something
which is legible and, as a bonus, correct.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
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Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
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- fix PCI interrupt assignment by emulating ioc3 interrupt pin register
- use pci_probe_only mode
- select correct page size in bridge
- remove no longer needed ioc3_sio_init() code
[Ralf: Fix for 64kB or larger pagesizes]
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
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Fix breakage introduced by converting hub_rt to clockevent.
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
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Changes in the generic bootmem code broke memory setup for IP27. This
patch fixes this by replacing lots of special IP27 code with generic
bootmon code. This has been tested only on a single node.
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
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The existing options are named CONFIG_CPU_R4300 and CONFIG_CPU_R4X00,
and they are directly below.
Reported-by: Robert P. J. Day <rpjday@crashcourse.ca>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
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The newly added check for valid stack pointer address breaks at least for
64bit kernels. Use __get_user() for accessing stack content to avoid crashes,
when doing the backtrace.
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
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Treat R4700 like R4600 in build_tlb_probe_entry. Without this fix kernel
will lock up.
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
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Add API to delete custom DDMA device ids create with
au1xxx_ddma_device_add().
Signed-off-by: Manuel Lauss <mano@roarinelk.homelinux.net>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
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au1xmmc.c driver depends on it, so export it for modules.
Signed-off-by: Manuel Lauss <mano@roarinelk.homelinux.net>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
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* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6:
sparc: switch /proc/led to seq_file
sparc64: IO accessors fix
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git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-tip
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-tip:
x86, fpu: fix CONFIG_PREEMPT=y corruption of application's FPU stack
suspend-vs-iommu: prevent suspend if we could not resume
x86: section mismatch fix
x86: fix Xorg crash with xf86MapVidMem error
x86: fix pointer type warning in arch/x86/mm/init_64.c:early_memtest
x86: fix bad pmd ffff810000207xxx(9090909090909090)
x86: ioremap fix failing nesting check
x86: fix broken math-emu with lazy allocation of fpu area
x86: enable preemption in delay
x86: disable preemption in native_smp_prepare_cpus
x86: fix APIC warning on 32bit v2
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* git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6.26:
sh: Add defconfig for RSK7203.
sh: Update SE7206 defconfig.
sh: Disable 4KSTACKS on nommu.
sh: fix miscompilation of ip_fast_csum with gcc >= 4.3
sh: module.c use kernel unaligned helpers
sh/kernel/cpu/irq/intc-sh5.c build fix
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Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Jürgen Mell reported an FPU state corruption bug under CONFIG_PREEMPT,
and bisected it to commit v2.6.19-1363-gacc2076, "i386: add sleazy FPU
optimization".
Add tsk_used_math() checks to prevent calling math_state_restore()
which can sleep in the case of !tsk_used_math(). This prevents
making a blocking call in __switch_to().
Apparently "fpu_counter > 5" check is not enough, as in some signal handling
and fork/exec scenarios, fpu_counter > 5 and !tsk_used_math() is possible.
It's a side effect though. This is the failing scenario:
process 'A' in save_i387_ia32() just after clear_used_math()
Got an interrupt and pre-empted out.
At the next context switch to process 'A' again, kernel tries to restore
the math state proactively and sees a fpu_counter > 0 and !tsk_used_math()
This results in init_fpu() during the __switch_to()'s math_state_restore()
And resulting in fpu corruption which will be saved/restored
(save_i387_fxsave and restore_i387_fxsave) during the remaining
part of the signal handling after the context switch.
Bisected-by: Jürgen Mell <j.mell@t-online.de>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Tested-by: Jürgen Mell <j.mell@t-online.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@kernel.org
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