Commit Graph

1159 Commits

Author SHA1 Message Date
Vitaly Kuzmichev
90c5ffe592 ARM: 6994/1: smp_twd: Fix typo in 'twd_timer_rate' printing
To get hundredths of MHz the rate needs to be divided by 10'000.
Here is an example:
 twd_timer_rate = 123456789
 Before the patch:
    twd_timer_rate / 1000000 = 123
    (twd_timer_rate / 1000000) % 100 = 23
    Result: 123.23MHz.
 After being fixed:
    twd_timer_rate / 1000000 = 123
    (twd_timer_rate / 10000) % 100 = 45
    Result: 123.45MHz.

Signed-off-by: Vitaly Kuzmichev <vkuzmichev@mvista.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-07-07 15:00:12 +01:00
Russell King
0371d3f7e8 ARM: move memory layout sanity checking before meminfo initialization
Ensure that the meminfo array is sanity checked before we pass the
memory to memblock.  This helps to ensure that memblock and meminfo
agree on the dimensions of memory, especially when more memory is
passed than the kernel can deal with.

Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-07-05 20:27:16 +01:00
Will Deacon
f4f38430c9 ARM: 6989/1: perf: do not start the PMU when no events are present
armpmu_enable can be called in situations where no events are present
(for example, from the event rotation tick after a profiled task has
exited). In this case, we currently start the PMU anyway which may
leave it active inevitably without any events being monitored.

This patch adds a simple check to the enabling code so that we avoid
starting the PMU when no events are present.

Cc: <stable@kernel.org>
Reported-by: Ashwin Chaugle <ashwinc@codeaurora.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-07-05 12:37:23 +01:00
Russell King
573619d165 ARM: SMP: wait for CPU to be marked active
When we bring a CPU online, we should wait for it to become active
before entering the idle thread, so we know that the scheduler and
thread migration is going to work.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-06-21 11:09:05 +01:00
Dave Martin
9a00318ead ARM: 6963/1: Thumb-2: Relax relocation requirements for non-function symbols
The "Thumb bit" of a symbol is only really meaningful for function
symbols (STT_FUNC).

However, sometimes a branch is relocated against a non-function
symbol; for example, PC-relative branches to anonymous assembler
local symbols are typically fixed up against the start-of-section
symbol, which is not a function symbol.  Some inline assembler
generates references of this type, such as fixup code generated by
macros in <asm/uaccess.h>.

The existing relocation code for R_ARM_THM_CALL/R_ARM_THM_JUMP24
interprets this case as an error, because the target symbol appears
to be an ARM symbol; but this is really not the case, since the
target symbol is just a base in these cases.  The addend defines
the precise offset to the target location, but since the addend is
encoded in a non-interworking Thumb branch instruction, there is no
explicit Thumb bit in the addend.  Because these instructions never
interwork, the implied Thumb bit in the addend is 1, and the
destination is Thumb by definition.

This patch removes the extraneous Thumb bit check for non-function
symbols, enabling modules containing the affected relocation types
to be loaded.  No modification to the actual relocation code is
required, since this code does not take bit[0] of the
location->destination offset into account in any case.

Function symbols are always checked for interworking conflicts, as
before.

Signed-off-by: Dave Martin <dave.martin@linaro.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-06-17 11:25:04 +01:00
Russell King
a9011580a9 ARM: extend Code: line by one 16-bit quantity for Thumb instructions
Dump out the following 16-bit instruction to the faulting instruction
in the Code: line.  This allows Thumb-2 instructions to be properly
encoded.

Tested-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-06-09 23:55:45 +01:00
Po-Yu Chuang
373ce3020b ARM: 6955/1: cmpxchg syscall should data abort if page not write
If the page to cmpxchg is user mode read only (not write),
we should simulate a data abort first.

Signed-off-by: Po-Yu Chuang <ratbert@faraday-tech.com>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-06-09 10:15:07 +01:00
Nicolas Pitre
f506cd48a4 ARM: 6953/1: DT: don't try to access physical address zero
If the DT physical address is zero, this is equivalent to no DT.
Especially when the actual RAM physical address is not located at zero,
the result of phys_to_virt() would point to la-la-land and crash the
kernel, which crash is completely silent this early during boot.

Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-06-09 10:15:06 +01:00
Ming Lei
9fc2552a68 ARM: 6952/1: fix lockdep warning of "unannotated irqs-off"
This patch fixes the lockdep warning of "unannotated irqs-off"[1].

After entering __irq_usr, arm core will disable interrupt automatically,
but __irq_usr does not annotate the irq disable, so lockdep may complain
the warning if it has chance to check this in irq handler.

This patch adds trace_hardirqs_off in __irq_usr before entering irq_handler
to handle the irq, also calls ret_to_user_from_irq to avoid calling
disable_irq again.

This is also a fix for irq off tracer.

[1], lockdep warning log of "unannotated irqs-off"

[   13.804687] ------------[ cut here ]------------
[   13.809570] WARNING: at kernel/lockdep.c:3335 check_flags+0x78/0x1d0()
[   13.816467] Modules linked in:
[   13.819732] Backtrace:
[   13.822357] [<c01cb42c>] (dump_backtrace+0x0/0x100) from [<c06abb14>] (dump_stack+0x20/0x24)
[   13.831268]  r6:c07d8c2c r5:00000d07 r4:00000000 r3:00000000
[   13.837280] [<c06abaf4>] (dump_stack+0x0/0x24) from [<c01ffc04>] (warn_slowpath_common+0x5c/0x74)
[   13.846649] [<c01ffba8>] (warn_slowpath_common+0x0/0x74) from [<c01ffc48>] (warn_slowpath_null+0x2c/0x34)
[   13.856781]  r8:00000000 r7:00000000 r6:c18b8194 r5:60000093 r4:ef182000
[   13.863708] r3:00000009
[   13.866485] [<c01ffc1c>] (warn_slowpath_null+0x0/0x34) from [<c0237d84>] (check_flags+0x78/0x1d0)
[   13.875823] [<c0237d0c>] (check_flags+0x0/0x1d0) from [<c023afc8>] (lock_acquire+0x4c/0x150)
[   13.884704] [<c023af7c>] (lock_acquire+0x0/0x150) from [<c06af638>] (_raw_spin_lock+0x4c/0x84)
[   13.893798] [<c06af5ec>] (_raw_spin_lock+0x0/0x84) from [<c01f9a44>] (sched_ttwu_pending+0x58/0x8c)
[   13.903320]  r6:ef92d040 r5:00000003 r4:c18b8180
[   13.908233] [<c01f99ec>] (sched_ttwu_pending+0x0/0x8c) from [<c01f9a90>] (scheduler_ipi+0x18/0x1c)
[   13.917663]  r6:ef183fb0 r5:00000003 r4:00000000 r3:00000001
[   13.923645] [<c01f9a78>] (scheduler_ipi+0x0/0x1c) from [<c01bc458>] (do_IPI+0x9c/0xfc)
[   13.932006] [<c01bc3bc>] (do_IPI+0x0/0xfc) from [<c06b0888>] (__irq_usr+0x48/0xe0)
[   13.939971] Exception stack(0xef183fb0 to 0xef183ff8)
[   13.945281] 3fa0:                                     ffffffc3 0001500c 00000001 0001500c
[   13.953948] 3fc0: 00000050 400b45f0 400d9000 00000000 00000001 400d9600 6474e552 bea05b3c
[   13.962585] 3fe0: 400d96c0 bea059c0 400b6574 400b65d8 20000010 ffffffff
[   13.969573]  r6:00000403 r5:fa240100 r4:ffffffff r3:20000010
[   13.975585] ---[ end trace efc4896ab0fb62cb ]---
[   13.980468] possible reason: unannotated irqs-off.
[   13.985534] irq event stamp: 1610
[   13.989044] hardirqs last  enabled at (1610): [<c01c703c>] no_work_pending+0x8/0x2c
[   13.997131] hardirqs last disabled at (1609): [<c01c7024>] ret_slow_syscall+0xc/0x1c
[   14.005371] softirqs last  enabled at (0): [<c01fe5e4>] copy_process+0x2cc/0xa24
[   14.013183] softirqs last disabled at (0): [<  (null)>]   (null)

Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-06-06 10:56:22 +01:00
Linus Torvalds
571503e100 Merge branch 'setns'
* setns:
  ns: Wire up the setns system call

Done as a merge to make it easier to fix up conflicts in arm due to
addition of sendmmsg system call
2011-05-28 10:51:01 -07:00
Eric W. Biederman
7b21fddd08 ns: Wire up the setns system call
32bit and 64bit on x86 are tested and working.  The rest I have looked
at closely and I can't find any problems.

setns is an easy system call to wire up.  It just takes two ints so I
don't expect any weird architecture porting problems.

While doing this I have noticed that we have some architectures that are
very slow to get new system calls.  cris seems to be the slowest where
the last system calls wired up were preadv and pwritev.  avr32 is weird
in that recvmmsg was wired up but never declared in unistd.h.  frv is
behind with perf_event_open being the last syscall wired up.  On h8300
the last system call wired up was epoll_wait.  On m32r the last system
call wired up was fallocate.  mn10300 has recvmmsg as the last system
call wired up.  The rest seem to at least have syncfs wired up which was
new in the 2.6.39.

v2: Most of the architecture support added by Daniel Lezcano <dlezcano@fr.ibm.com>
v3: ported to v2.6.36-rc4 by: Eric W. Biederman <ebiederm@xmission.com>
v4: Moved wiring up of the system call to another patch
v5: ported to v2.6.39-rc6
v6: rebased onto parisc-next and net-next to avoid syscall  conflicts.
v7: ported to Linus's latest post 2.6.39 tree.

>  arch/blackfin/include/asm/unistd.h     |    3 ++-
>  arch/blackfin/mach-common/entry.S      |    1 +
Acked-by: Mike Frysinger <vapier@gentoo.org>

Oh - ia64 wiring looks good.
Acked-by: Tony Luck <tony.luck@intel.com>

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-05-28 10:48:39 -07:00
Russell King
239df0fd5e Merge branches 'devel', 'devel-stable' and 'fixes' into for-linus 2011-05-27 22:59:57 +01:00
Catalin Marinas
d427958a46 ARM: 6942/1: mm: make TTBR1 always point to swapper_pg_dir on ARMv6/7
This patch makes TTBR1 point to swapper_pg_dir so that global, kernel
mappings can be used exclusively on v6 and v7 cores where they are
needed.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-05-26 12:14:32 +01:00
Russell King
a85fab1c79 ARM: add sendmmsg syscall
Commit 228e548e (net: Add sendmmsg socket system call) added the new
sendmmsg syscall.  Add this to the syscall table for ARM.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-05-26 12:12:13 +01:00
Dave Martin
dc2eb928a1 ARM: 6938/1: fiq: Refactor {get,set}_fiq_regs() for Thumb-2
* To remove the risk of inconvenient register allocation decisions
   by the compiler, these functions are separated out as pure
   assembler.

 * The apcs frame manipulation code is not applicable for Thumb-2
   (and also not easily compatible).  Since it's not essential to
   have a full frame on these leaf assembler functions, the frame
   manipulation is removed, in the interests of simplicity.

 * Split up ldm/stm instructions to be compatible with Thumb-2,
   as well as avoiding instruction forms deprecated on >= ARMv7.

Signed-off-by: Dave Martin <dave.martin@linaro.org>
Reviewed-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-05-26 10:31:06 +01:00
Russell King
ae1d3b974e Merge branch 'for-rmk' of git://github.com/at91linux/linux-2.6-at91 into devel-stable 2011-05-26 00:41:21 +01:00
Russell King
03eb14199e Merge branch 'devicetree/arm-next' of git://git.secretlab.ca/git/linux-2.6 into devel-stable 2011-05-25 00:08:17 +01:00
Linus Torvalds
5129df03d0 Merge branch 'for-2.6.40' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu
* 'for-2.6.40' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu:
  percpu: Unify input section names
  percpu: Avoid extra NOP in percpu_cmpxchg16b_double
  percpu: Cast away printk format warning
  percpu: Always align percpu output section to PAGE_SIZE

Fix up fairly trivial conflict in arch/x86/include/asm/percpu.h as per Tejun
2011-05-24 11:53:42 -07:00
Russell King
ec19628d72 Merge branches 'consolidate', 'ep93xx', 'fixes', 'misc', 'mmci', 'remove' and 'spear' into for-linus 2011-05-23 19:27:40 +01:00
Russell King
4b60e5f90d Merge branches 'consolidate-clksrc', 'consolidate-flash', 'consolidate-generic', 'consolidate-smp', 'consolidate-stmp' and 'consolidate-zones' into consolidate 2011-05-23 18:05:10 +01:00
Russell King
0f7b332f97 ARM: consolidate SMP cross call implementation
Rather than having each platform class provide a mach/smp.h header for
smp_cross_call(), arrange for them to register the function with the
core ARM SMP code instead.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-05-23 16:53:17 +01:00
Grant Likely
93c02ab40a arm/dt: probe for platforms via the device tree
If a dtb is passed to the kernel then the kernel needs to iterate
through compiled-in mdescs looking for one that matches and move the
dtb data to a safe location before it gets accidentally overwritten by
the kernel.

This patch creates a new function, setup_machine_fdt() which is
analogous to the setup_machine_atags() created in the previous patch.
It does all the early setup needed to use a device tree machine
description.

v5: - Print warning with neither dtb nor atags are passed to the kernel
    - Fix bug in setting of __machine_arch_type to the selected machine,
      not just the last machine in the list.
      Reported-by: Tixy <tixy@yxit.co.uk>
    - Copy command line directly into boot_command_line instead of cmd_line
v4: - Dump some output when a matching machine_desc cannot be found
v3: - Added processing of reserved list.
    - Backed out the v2 change that copied instead of reserved the
      dtb.  dtb is reserved again and the real problem was fixed by
      using alloc_bootmem_align() for early allocation of RAM for
      unflattening the tree.
    - Moved cmd_line and initrd changes to earlier patch to make series
      bisectable.
v2: Changed to save the dtb by copying into an allocated buffer.
    - Since the dtb will very likely be passed in the first 16k of ram
      where the interrupt vectors live, memblock_reserve() is
      insufficient to protect the dtb data.

[based on work originally written by Jeremy Kerr <jeremy.kerr@canonical.com>]
Tested-by: Tony Lindgren <tony@atomide.com>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-05-23 09:30:20 -06:00
Grant Likely
6291319d48 arm/dt: consolidate atags setup into setup_machine_atags
In preparation for adding device tree support, this patch consolidates
all of the atag-specific setup into a single function.

v5: - drop double printk("Machine; %s\n", ...); call.
    - leave copying boot_command_line in setup_arch() since it isn't
      atags specific.
v4: - adapt to the removal of lookup_machine_type()
    - break out dump of machine_desc table into dump_machine_table()
      because the device tree probe code will use it.
    - Add for_each_machine_desc() macro

Tested-by: Tony Lindgren <tony@atomide.com>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-05-23 09:30:20 -06:00
Mark Rutland
57ce9bb39b ARM: 6902/1: perf: Remove erroneous check on active_events
When initialising a PMU, there is a check to protect against races with
other CPUs filling all of the available event slots. Since armpmu_add
checks that an event can be scheduled, we do not need to do this at
initialisation time. Furthermore the current code is broken because it
assumes that atomic_inc_not_zero will unconditionally increment
active_counts and then tries to decrement it again on failure.

This patch removes the broken, redundant code.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: Jamie Iles <jamie@jamieiles.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-05-20 22:39:17 +01:00
Linus Torvalds
39ab05c8e0 Merge branch 'driver-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6
* 'driver-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6: (44 commits)
  debugfs: Silence DEBUG_STRICT_USER_COPY_CHECKS=y warning
  sysfs: remove "last sysfs file:" line from the oops messages
  drivers/base/memory.c: fix warning due to "memory hotplug: Speed up add/remove when blocks are larger than PAGES_PER_SECTION"
  memory hotplug: Speed up add/remove when blocks are larger than PAGES_PER_SECTION
  SYSFS: Fix erroneous comments for sysfs_update_group().
  driver core: remove the driver-model structures from the documentation
  driver core: Add the device driver-model structures to kerneldoc
  Translated Documentation/email-clients.txt
  RAW driver: Remove call to kobject_put().
  reboot: disable usermodehelper to prevent fs access
  efivars: prevent oops on unload when efi is not enabled
  Allow setting of number of raw devices as a module parameter
  Introduce CONFIG_GOOGLE_FIRMWARE
  driver: Google Memory Console
  driver: Google EFI SMI
  x86: Better comments for get_bios_ebda()
  x86: get_bios_ebda_length()
  misc: fix ti-st build issues
  params.c: Use new strtobool function to process boolean inputs
  debugfs: move to new strtobool
  ...

Fix up trivial conflicts in fs/debugfs/file.c due to the same patch
being applied twice, and an unrelated cleanup nearby.
2011-05-19 18:24:11 -07:00
Linus Torvalds
80fe02b5da Merge branches 'sched-core-for-linus' and 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (60 commits)
  sched: Fix and optimise calculation of the weight-inverse
  sched: Avoid going ahead if ->cpus_allowed is not changed
  sched, rt: Update rq clock when unthrottling of an otherwise idle CPU
  sched: Remove unused parameters from sched_fork() and wake_up_new_task()
  sched: Shorten the construction of the span cpu mask of sched domain
  sched: Wrap the 'cfs_rq->nr_spread_over' field with CONFIG_SCHED_DEBUG
  sched: Remove unused 'this_best_prio arg' from balance_tasks()
  sched: Remove noop in alloc_rt_sched_group()
  sched: Get rid of lock_depth
  sched: Remove obsolete comment from scheduler_tick()
  sched: Fix sched_domain iterations vs. RCU
  sched: Next buddy hint on sleep and preempt path
  sched: Make set_*_buddy() work on non-task entities
  sched: Remove need_migrate_task()
  sched: Move the second half of ttwu() to the remote cpu
  sched: Restructure ttwu() some more
  sched: Rename ttwu_post_activation() to ttwu_do_wakeup()
  sched: Remove rq argument from ttwu_stat()
  sched: Remove rq->lock from the first half of ttwu()
  sched: Drop rq->lock from sched_exec()
  ...

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  sched: Fix rt_rq runtime leakage bug
2011-05-19 17:41:22 -07:00
Rafael J. Wysocki
2d2a9163bd Merge branch 'syscore' into for-linus
* syscore:
  PM: Remove sysdev suspend, resume and shutdown operations
  PM / PowerPC: Use struct syscore_ops instead of sysdevs for PM
  PM / UNICORE32: Use struct syscore_ops instead of sysdevs for PM
  PM / AVR32: Use struct syscore_ops instead of sysdevs for PM
  PM / Blackfin: Use struct syscore_ops instead of sysdevs for PM
  ARM / Samsung: Use struct syscore_ops for "core" power management
  ARM / PXA: Use struct syscore_ops for "core" power management
  ARM / SA1100: Use struct syscore_ops for "core" power management
  ARM / Integrator: Use struct syscore_ops for core PM
  ARM / OMAP: Use struct syscore_ops for "core" power management
  ARM: Use struct syscore_ops instead of sysdevs for PM in common code
2011-05-17 23:23:40 +02:00
Dave Martin
5be6f62b00 ARM: 6883/1: ptrace: Migrate to regsets framework
This patch migrates the implementation of the ptrace interface for
the core integer registers, legacy FPA registers and VFP registers
to use the regsets framework.

As an added bonus, all this stuff gets included in coredumps
at no extra cost.  Without this patch, coredumps contained no
VFP state.

Third-party extension register sets (iwmmx, crunch) are not migrated
by this patch, and continue to use the old implementation;
these should be migratable without much extra work.

Signed-off-by: Dave Martin <dave.martin@linaro.org>
Acked-by: Will Deacon <Will.Deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-05-14 21:36:55 +01:00
Greg Kroah-Hartman
82a3242e11 sysfs: remove "last sysfs file:" line from the oops messages
On some arches (x86, sh, arm, unicore, powerpc) the oops message would
print out the last sysfs file accessed.

This was very useful in finding a number of sysfs and driver core bugs
in the 2.5 and early 2.6 development days, but it has been a number of
years since this file has actually helped in debugging anything that
couldn't also be trivially determined from the stack traceback.

So it's time to delete the line.  This is good as we need all the space
we can get for oops messages at times on consoles.

Acked-by: Phil Carmody <ext-phil.2.carmody@nokia.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-05-13 16:05:51 -07:00
Linus Torvalds
75c0b3b466 Merge branch 'fixes' of master.kernel.org:/home/rmk/linux-2.6-arm
* 'fixes' of master.kernel.org:/home/rmk/linux-2.6-arm:
  ARM: 6870/1: The mandatory barrier rmb() must be a dsb() in for device accesses
  ARM: 6892/1: handle ptrace requests to change PC during interrupted system calls
  ARM: 6890/1: memmap: only free allocated memmap entries when using SPARSEMEM
  ARM: zImage: the page table memory must be considered before relocation
  ARM: zImage: make sure not to relocate on top of the relocation code
  ARM: zImage: Fix bad SP address after relocating kernel
  ARM: zImage: make sure the stack is 64-bit aligned
  ARM: RiscPC: acornfb: fix section mismatches
  ARM: RiscPC: etherh: fix section mismatches
2011-05-12 07:53:06 -07:00
Arnd Bergmann
2af68df02f ARM: 6892/1: handle ptrace requests to change PC during interrupted system calls
GDB's interrupt.exp test cases currenly fail on ARM.  The problem is how do_signal
handled restarting interrupted system calls:

The entry.S assembler code determines that we come from a system call; and that
information is passed as "syscall" parameter to do_signal.  That routine then
calls get_signal_to_deliver [*] and if a signal is to be delivered, calls into
handle_signal.  If a system call is to be restarted either after the signal
handler returns, or if no handler is to be called in the first place, the PC
is updated after the get_signal_to_deliver call, either in handle_signal (if
we have a handler) or at the end of do_signal (otherwise).

Now the problem is that during [*], the call to get_signal_to_deliver, a ptrace
intercept may happen.  During this intercept, the debugger may change registers,
including the PC.  This is done by GDB if it wants to execute an "inferior call",
i.e. the execution of some code in the debugged program triggered by GDB.

To this purpose, GDB will save all registers, allocate a stack frame, set up
PC and arguments as appropriate for the call, and point the link register to
a dummy breakpoint instruction.  Once the process is restarted, it will execute
the call and then trap back to the debugger, at which point GDB will restore
all registers and continue original execution.

This generally works fine.  However, now consider what happens when GDB attempts
to do exactly that while the process was interrupted during execution of a to-be-
restarted system call:  do_signal is called with the syscall flag set; it calls
get_signal_to_deliver, at which point the debugger takes over and changes the PC
to point to a completely different place.  Now get_signal_to_deliver returns
without a signal to deliver; but now do_signal decides it should be restarting
a system call, and decrements the PC by 2 or 4 -- so it now points to 2 or 4
bytes before the function GDB wants to call -- which leads to a subsequent crash.

To fix this problem, two things need to be supported:
- do_signal must be able to recognize that get_signal_to_deliver changed the PC
  to a different location, and skip the restart-syscall sequence
- once the debugger has restored all registers at the end of the inferior call
  sequence, do_signal must recognize that *now* it needs to restart the pending
  system call, even though it was now entered from a breakpoint instead of an
  actual svc instruction

This set of issues is solved on other platforms, usually by one of two
mechanisms:

- The status information "do_signal is handling a system call that may need
  restarting" is itself carried in some register that can be accessed via
  ptrace.  This is e.g. on Intel the "orig_eax" register; on Sparc the kernel
  defines a magic extra bit in the flags register for this purpose.
  This allows GDB to manage that state: reset it when doing an inferior call,
  and restore it after the call is finished.

- On s390, do_signal transparently handles this problem without requiring
  GDB interaction, by performing system call restarting in the following
  way: first, adjust the PC as necessary for restarting the call.  Then,
  call get_signal_to_deliver; and finally just continue execution at the
  PC.  This way, if GDB does not change the PC, everything is as before.
  If GDB *does* change the PC, execution will simply continue there --
  and once GDB restores the PC it saved at that point, it will automatically
  point to the *restarted* system call.  (There is the minor twist how to
  handle system calls that do *not* need restarting -- do_signal will undo
  the PC change in this case, after get_signal_to_deliver has returned, and
  only if ptrace did not change the PC during that call.)

Because there does not appear to be any obvious register to carry the
syscall-restart information on ARM, we'd either have to introduce a new
artificial ptrace register just for that purpose, or else handle the issue
transparently like on s390.  The patch below implements the second option;
using this patch makes the interrupt.exp test cases pass on ARM, with no
regression in the GDB test suite otherwise.

Cc: patches@linaro.org
Signed-off-by: Ulrich Weigand <ulrich.weigand@linaro.org>
Signed-off-by: Arnd Bergmann <arnd.bergmann@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-05-12 10:52:00 +01:00
Victor Boivie
4394c12442 ARM: 6893/1: Allow for kernel command line concatenation
This patch allows the provided CONFIG_CMDLINE to be concatenated
with the one provided by the boot loader. This is useful to
merge the static values defined in CONFIG_CMDLINE with the
boot loader's (possibly) more dynamic values, such as startup
reasons and more.

Signed-off-by: Victor Boivie <victor.boivie@sonyericsson.com>
Reviewed-by: Bjorn Andersson <bjorn.andersson@sonyericsson.com>
Signed-off-by: Oskar Andero <oskar.andero@sonyericsson.com>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-05-12 10:13:22 +01:00
Ingo Molnar
9cb5baba5e Merge commit 'v2.6.39-rc7' into sched/core 2011-05-12 09:36:18 +02:00
Grant Likely
9eb8f6743b arm/dt: Allow CONFIG_OF on ARM
Add some basic empty infrastructure for DT support on ARM.

v5: - Fix off-by-one error in size calculation of initrd
    - Stop mucking with cmd_line, and load command line from dt into
      boot_command_line instead which matches the behaviour of ATAGS booting
v3: - moved cmd_line export and initrd setup to this patch to make the
      series bisectable.
    - switched to alloc_bootmem_align() for allocation when
      unflattening the device tree.  memblock_alloc() was not the
      right interface.

Signed-off-by: Jeremy Kerr <jeremy.kerr@canonical.com>
Tested-by: Tony Lindgren <tony@atomide.com>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-05-11 15:14:29 +02:00
Grant Likely
4c2896e88d arm/dt: Make __vet_atags also accept a dtb image
The dtb is passed to the kernel via register r2, which is the same
method that is used to pass an atags pointer.  This patch modifies
__vet_atags to not clear r2 when it encounters a dtb image.

v2: fixed bugs pointed out by Nicolas Pitre

Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-05-11 15:12:32 +02:00
Ingo Molnar
98bb318864 Merge branch 'perf/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing into perf/urgent 2011-05-04 20:33:42 +02:00
Dan Rosenberg
0f22072ab5 ARM: 6891/1: prevent heap corruption in OABI semtimedop
When CONFIG_OABI_COMPAT is set, the wrapper for semtimedop does not
bound the nsops argument.  A sufficiently large value will cause an
integer overflow in allocation size, followed by copying too much data
into the allocated buffer.  Fix this by restricting nsops to SEMOPM.
Untested.

Cc: stable@kernel.org
Signed-off-by: Dan Rosenberg <drosenberg@vsecurity.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-04-29 15:53:14 +01:00
Russell King
408133e9dc Merge branch 'kprobes' of git://git.linaro.org/people/nico/linux into fixes 2011-04-29 11:02:45 +01:00
Jon Medhurst
cdc2536115 ARM: kprobes: Tidy-up kprobes-decode.c
- Remove coding standard violations reported by checkpatch.pl
- Delete comment about handling of conditional branches which is no
  longer true.
- Delete comment at end of file which lists all ARM instructions. This
  duplicates data available in the ARM ARM and seems like an
  unnecessary maintenance burden to keep this up to date and accurate.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:41:01 -04:00
Jon Medhurst
9425493078 ARM: kprobes: Add emulation of hint instructions like NOP and WFI
Being able to probe NOP instructions is useful for hard-coding probeable
locations and is used by the kprobes test code.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:41:01 -04:00
Jon Medhurst
20e8155e24 ARM: kprobes: Add emulation of SBFX, UBFX, BFI and BFC instructions
These bit field manipulation instructions occur several thousand
times in an ARMv7 kernel.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:41:00 -04:00
Jon Medhurst
c9836777d5 ARM: kprobes: Add emulation of MOVW and MOVT instructions
The MOVW and MOVT instructions account for approximately 7% of all
instructions in a ARMv7 kernel as GCC uses them instead of a literal
pool.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:59 -04:00
Jon Medhurst
f704a6e25b ARM: kprobes: Reject probing of undefined data processing instructions
The instruction decoding in space_cccc_000x needs to reject probing of
instructions with undefined patterns as they may in future become
defined and then emulated faultily - as has already happened with the
SMC instruction.

This fix is achieved by testing for the instruction patterns we want to
probe and making the the default fall-through paths reject probes. This
also allows us to remove some explicit tests for instructions that we
wish to reject, as that is now the default action.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:59 -04:00
Jon Medhurst
72c2bab2be ARM: kprobes: Remove redundant code in space_1111
The tests to explicitly reject probing CPS, RFE and SRS instructions
are redundant as the default case is now to reject undecoded patterns.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:59 -04:00
Jon Medhurst
41713d1396 ARM: kprobes: Fix emulation of PLD instructions
The PLD instructions wasn't being decoded correctly and the emulation
code wasn't adjusting PC correctly.

As the PLD instruction is only a performance hint we emulate it as a
simple nop, and we can broaden the instruction decoding to take into
account newer PLI and PLDW instructions.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:59 -04:00
Jon Medhurst
f0aeb8bff0 ARM: kprobes: Reject probing of SETEND instructions
The emulation of SETEND was broken as it changed the endianess for
the running kprobes handling code. Rather than adding a new simulation
routine to fix this we'll just reject probing of SETEND as these should
be very rare in the kernel.

Note, the function emulate_none is now unused but it is left in the
source code as future patches will use it.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:59 -04:00
Jon Medhurst
ac211c6994 ARM: kprobes: Consolidate stub decoding functions
Following the change to remove support for coprocessor instructions
we are left with three stub functions which can be consolidated.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:59 -04:00
Jon Medhurst
fa1a03b429 ARM: kprobes: Reject probing of all coprocessor instructions
The kernel doesn't currently support VFP or Neon code, and probing of
code with CP15 operations is fraught with bad consequences. Therefore we
don't need the ability to probe coprocessor instructions and the code to
support this can be removed.

The removed code also had at least two bugs:
 - MRC into R15 should set CPSR not trash PC
 - LDC and STC which use PC as base register needed the address offset by 8

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:58 -04:00
Jon Medhurst
c6e4ae3291 ARM: kprobes: Fix emulation of USAD8 instructions
The USAD8 instruction wasn't being explicitly decoded leading
to the incorrect emulation routine being called. It can be correctly
decoded in the same way as the signed multiply instructions so we move
the decoding there.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:58 -04:00
Jon Medhurst
038c3839c9 ARM: kprobes: Fix emulation of SMUAD, SMUSD and SMMUL instructions
The signed multiply instructions were being decoded incorrectly.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:58 -04:00