linux-stable.git/arch/mips/include, branch linux-2.6.33.y

compat: Make compat_alloc_user_space() incorporate the access_ok()

2011-03-21T19:44:13+00:00

commit c41d68a513c71e35a14f66d71782d27a79a81ea6 upstream.

compat_alloc_user_space() expects the caller to independently call
access_ok() to verify the returned area.  A missing call could
introduce problems on some architectures.

This patch incorporates the access_ok() check into
compat_alloc_user_space() and also adds a sanity check on the length.
The existing compat_alloc_user_space() implementations are renamed
arch_compat_alloc_user_space() and are used as part of the
implementation of the new global function.

This patch assumes NULL will cause __get_user()/__put_user() to either
fail or access userspace on all architectures.  This should be
followed by checking the return value of compat_access_user_space()
for NULL in the callers, at which time the access_ok() in the callers
can also be removed.

Reported-by: Ben Hawkes 
Signed-off-by: H. Peter Anvin 
Acked-by: Benjamin Herrenschmidt 
Acked-by: Chris Metcalf 
Acked-by: David S. Miller 
Acked-by: Ingo Molnar 
Acked-by: Thomas Gleixner 
Acked-by: Tony Luck 
Cc: Andrew Morton 
Cc: Arnd Bergmann 
Cc: Fenghua Yu 
Cc: H. Peter Anvin 
Cc: Heiko Carstens 
Cc: Helge Deller 
Cc: James Bottomley 
Cc: Kyle McMartin 
Cc: Martin Schwidefsky 
Cc: Paul Mackerras 
Cc: Ralf Baechle 
Signed-off-by: Greg Kroah-Hartman

MIPS FPU emulator: allow Cause bits of FCSR to be writeable by ctc1

2010-08-02T17:26:48+00:00

commit 95e8f634d7a3ea5af40ec3fa42c8a152fd3a0624 upstream.

    In the FPU emulator code of the MIPS, the Cause bits of the FCSR register
    are not currently writeable by the ctc1 instruction.  In odd corner cases,
    this can cause problems.  For example, a case existed where a divide-by-zero
    exception was generated by the FPU, and the signal handler attempted to
    restore the FPU registers to their state before the exception occurred.  In
    this particular setup, writing the old value to the FCSR register would
    cause another divide-by-zero exception to occur immediately.  The solution
    is to change the ctc1 instruction emulator code to allow the Cause bits of
    the FCSR register to be writeable.  This is the behaviour of the hardware
    that the code is emulating.

    This problem was found by Shane McDonald, but the credit for the fix goes
    to Kevin Kissell.  In Kevin's words:

    I submit that the bug is indeed in that ctc_op:  case of the emulator.  The
    Cause bits (17:12) are supposed to be writable by that instruction, but the
    CTC1 emulation won't let them be updated by the instruction.  I think that
    actually if you just completely removed lines 387-388 [...] things would
    work a good deal better.  At least, it would be a more accurate emulation of
    the architecturally defined FPU.  If I wanted to be really, really pedantic
    (which I sometimes do), I'd also protect the reserved bits that aren't
    necessarily writable.

Signed-off-by: Shane McDonald 
To: anemo@mba.ocn.ne.jp
To: kevink@paralogos.com
To: sshtylyov@mvista.com
Patchwork: http://patchwork.linux-mips.org/patch/1205/
Signed-off-by: Ralf Baechle 
Cc: Ben Hutchings 
Signed-off-by: Greg Kroah-Hartman

MIPS: Sibyte: Apply M3 workaround only on affected chip types and versions.

2010-05-12T22:03:17+00:00

(cherry picked from commit e65c7f33d75e977350ca350573d93c517ec02776)

Previously it was unconditionally used on all Sibyte family SOCs.  The
M3 bug has to be handled in the TLB exception handler which is extremly
performance sensitive, so this modification is expected to deliver around
2-3% performance improvment.  This is important as required changes to the
M3 workaround will make it more costly.

Signed-off-by: Ralf Baechle 
Signed-off-by: Greg Kroah-Hartman

Merge branch 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus

2010-02-02T20:45:33+00:00

* 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus:
  MIPS: 64-bit: Detect virtual memory size
  MIPS: AR7: Fix USB slave mem range typo
  MIPS: Alchemy: Fix dbdma ring destruction memory debugcheck.

MIPS: 64-bit: Detect virtual memory size

2010-02-02T18:56:23+00:00

Linux kernel 2.6.32 and later allocate address space from the top of the
kernel virtual memory address space.

This patch implements virtual memory size detection for 64 bit MIPS CPUs
to avoid resulting crashes.

Signed-off-by: Guenter Roeck 
Cc: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/935/
Reviewed-by: David Daney 
Signed-off-by: Ralf Baechle

MIPS: Alchemy: Fix dbdma ring destruction memory debugcheck.

2010-02-01T19:30:25+00:00

DBDMA descriptors need to be located at 32-byte aligned addresses;
however kmalloc in conjunction with the SLAB allocator and
CONFIG_DEBUG_SLUB enabled doesn't deliver any.  The dbdma code works
around that by allocating a larger area and realigning the start
address within it.

When freeing a channel however this adjustment is not taken into
account which results in an oops:

Kernel bug detected[#1]:
[...]
Call Trace:
[<80186010>] cache_free_debugcheck+0x284/0x318
[<801869d8>] kfree+0xe8/0x2a0
[<8010b31c>] au1xxx_dbdma_chan_free+0x2c/0x7c
[<80388dc8>] au1x_pcm_dbdma_free+0x34/0x4c
[<80388fa8>] au1xpsc_pcm_close+0x28/0x38
[<80383cb8>] soc_codec_close+0x14c/0x1cc
[<8036dbb4>] snd_pcm_release_substream+0x60/0xac
[<8036dc40>] snd_pcm_release+0x40/0xa0
[<8018c7a8>] __fput+0x11c/0x228
[<80188f60>] filp_close+0x7c/0x98
[<80189018>] sys_close+0x9c/0xe4
[<801022a0>] stack_done+0x20/0x3c

Fix this by recording the address delivered by kmalloc() and using
it as parameter to kfree().

This fix is only necessary with the SLAB allocator and CONFIG_DEBUG_SLAB
enabled;  non-debug SLAB, SLUB do return nicely aligned addresses,
debug-enabled SLUB currently panics early in the boot process.

Signed-off-by: Manuel Lauss 
To: Linux-MIPS 
Cc: Manuel Lauss 
Patchwork: http://patchwork.linux-mips.org/patch/878/
Signed-off-by: Ralf Baechle

MIPS: PowerTV: Fix support for timer interrupts with > 64 external IRQs

2010-01-27T23:03:31+00:00

The MIPS processor is limited to 64 external interrupt sources. Using a
greater number without IRQ sharing requires reading platform-specific
registers. On such platforms, reading the IntCtl register to determine
which interrupt corresponds to a timer interrupt will not work.

On MIPSR2 systems there is a solution - the TI bit in the Cause register,
specifically indicates that a timer interrupt has occured. This patch uses
that bit to detect interrupts for MIPSR2 processors, which may be expected
to work regardless of how the timer interrupt may be routed in the hardware.

Signed-off-by: David VomLehn (dvomlehn@cisco.com)
To: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/804/
Signed-off-by: Ralf Baechle

MIPS: PowerTV: Streamline access to platform device registers

2010-01-27T23:03:31+00:00

Pre-compute addresses for the basic ASIC registers. This speeds up access
and allows memory for unused configurations to be freed. In addition,
uninitialized register addresses will be returned as NULL to catch bad
usage quickly.

Signed-off-by: David VomLehn 
To: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/806/
Signed-off-by: Ralf Baechle

MIPS: cpumask_of_node() should handle -1 as a node

2010-01-12T17:19:37+00:00

pcibus_to_node can return -1 if we cannot determine which node a pci bus
is on. If passed -1, cpumask_of_node will negatively index the lookup array
and pull in random data:

# cat /sys/devices/pci0000:00/0000:00:01.0/local_cpus
00000000,00000003,00000000,00000000
# cat /sys/devices/pci0000:00/0000:00:01.0/local_cpulist
64-65

Change cpumask_of_node to check for -1 and return cpu_all_mask in this
case:

# cat /sys/devices/pci0000:00/0000:00:01.0/local_cpus
ffffffff,ffffffff,ffffffff,ffffffff
# cat /sys/devices/pci0000:00/0000:00:01.0/local_cpulist
0-127

Signed-off-by: Anton Blanchard 
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Cc: Rusty Russell 
Cc: Andrew Morton 
Patchwork: http://patchwork.linux-mips.org/patch/831/
Signed-off-by: Ralf Baechle

Merge branch 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus

2009-12-18T00:38:06+00:00

* 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus: (71 commits)
  MIPS: Lasat: Fix botched changes to sysctl code.
  RTC: rtc-cmos.c: Fix warning on MIPS
  MIPS: Cleanup random differences beween lmo and Linus' kernel.
  MIPS: No longer hardwire CONFIG_EMBEDDED to y
  MIPS: Fix and enhance built-in kernel command line
  MIPS: eXcite: Remove platform.
  MIPS: Loongson: Cleanups of serial port support
  MIPS: Lemote 2F: Suspend CS5536 MFGPT Timer
  MIPS: Excite: move iodev_remove to .devexit.text
  MIPS: Lasat: Convert to proc_fops / seq_file
  MIPS: Cleanup signal code initialization
  MIPS: Modularize COP2 handling
  MIPS: Move EARLY_PRINTK to Kconfig.debug
  MIPS: Yeeloong 2F: Cleanup reset logic using the new ec_write function
  MIPS: Yeeloong 2F: Add LID open event as the wakeup event
  MIPS: Yeeloong 2F: Add basic EC operations
  MIPS: Move several variables from .bss to .init.data
  MIPS: Tracing: Make function graph tracer work with -mmcount-ra-address
  MIPS: Tracing: Reserve $12(t0) for mcount-ra-address of gcc 4.5
  MIPS: Tracing: Make ftrace for MIPS work without -fno-omit-frame-pointer
  ...