linux-stable.git/arch/arm/kernel, branch v4.2.1

ARM: 8410/1: VDSO: fix coarse clock monotonicity regression

2015-08-11T12:42:44+00:00

Since 906c55579a63 ("timekeeping: Copy the shadow-timekeeper over the
real timekeeper last") it has become possible on ARM to:

- Obtain a CLOCK_MONOTONIC_COARSE or CLOCK_REALTIME_COARSE timestamp
  via syscall.
- Subsequently obtain a timestamp for the same clock ID via VDSO which
  predates the first timestamp (by one jiffy).

This is because ARM's update_vsyscall is deriving the coarse time
using the __current_kernel_time interface, when it should really be
using the timekeeper object provided to it by the timekeeping core.
It happened to work before only because __current_kernel_time would
access the same timekeeper object which had been passed to
update_vsyscall.  This is no longer the case.

Cc: stable@vger.kernel.org
Fixes: 906c55579a63 ("timekeeping: Copy the shadow-timekeeper over the real timekeeper last")
Signed-off-by: Nathan Lynch 
Acked-by: Will Deacon 
Signed-off-by: Russell King

ARM: 8409/1: Mark ret_fast_syscall as a function

2015-08-07T18:57:02+00:00

ret_fast_syscall runs when user space makes a syscall. However it
needs to be marked as such so the ELF information is correct. Before
it was:

   101: 8000f300     0 NOTYPE  LOCAL  DEFAULT    2 ret_fast_syscall

But with this change it correctly shows as:

   101: 8000f300    96 FUNC    LOCAL  DEFAULT    2 ret_fast_syscall

I see this function when using perf to unwind call stacks from kernel
space to user space. Without this change I would need to add some
special case logic when using the vmlinux ELF information.

Signed-off-by: Drew Richardson 
Acked-by: Nicolas Pitre 
Signed-off-by: Russell King

ARM: 8408/1: Fix the secondary_startup function in Big Endian case

2015-08-07T18:57:02+00:00

Since the commit "b2c3e38a5471 ARM: redo TTBR setup code for LPAE",
the setup code had been reworked. As a result the secondary CPUs
failed to come online in Big Endian.

As explained by Russell, the new code expected the value in r4/r5 to
be the least significant 32bits in r4 and the most significant 32bits
in r5. However, in the secondary code, we load this using ldrd, which
on BE reverses that.

This patch swap r4/r5 after the ldrd. It is done using the xor
instructions in order to not use a temporary register.

Signed-off-by: Gregory CLEMENT 
Signed-off-by: Russell King

ARM: 8402/1: perf: Don't use of_node after putting it

2015-07-17T14:08:38+00:00

It's possible, albeit unlikely, that using the of_node here will
reference freed memory. Call of_node_put() after printing the
name to be safe.

Signed-off-by: Stephen Boyd 
Signed-off-by: Will Deacon 
Signed-off-by: Russell King

ARM: 8400/1: use virt_to_idmap to get phys_reset address

2015-07-17T14:08:17+00:00

This patch is to get correct physical address of the reset function for
PAE systems, which use aliased physical memory for booting.

See the "ARM: mm: Introduce virt_to_idmap() with an arch hook" for details.

Signed-off-by: Vitaly Andrianov 
Signed-off-by: Russell King

Merge branch 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm

2015-07-07T22:19:09+00:00

Pull ARM updates from Russell King:
 "These are late by a week; they should have been merged during the
  merge window, but unfortunately, the ARM kernel build/boot farms were
  indicating random failures, and it wasn't clear whether the cause was
  something in these changes or something during the merge window.

  This is a set of merge window fixes with some documentation additions"

* 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm:
  ARM: avoid unwanted GCC memset()/memcpy() optimisations for IO variants
  ARM: pgtable: document mapping types
  ARM: io: convert ioremap*() to functions
  ARM: io: fix ioremap_wt() implementation
  ARM: io: document ARM specific behaviour of ioremap*() implementations
  ARM: fix lockdep unannotated irqs-off warning
  ARM: 8397/1: fix vdsomunge not to depend on glibc specific error.h
  ARM: add helpful message when truncating physical memory
  ARM: add help text for HIGHPTE configuration entry
  ARM: fix DEBUG_SET_MODULE_RONX build dependencies
  ARM: 8396/1: use phys_addr_t in pfn_to_kaddr()
  ARM: 8394/1: update memblock limit after mapping lowmem
  ARM: 8393/1: smp: Fix suspicious RCU usage with ipi tracepoints

Merge branches 'fixes' and 'ioremap' into for-linus

2015-07-07T11:35:33+00:00

ARM: avoid unwanted GCC memset()/memcpy() optimisations for IO variants

2015-07-03T19:46:15+00:00

We don't want GCC optimising our memset_io(), memcpy_fromio() or
memcpy_toio() variants, so we must not call one of the standard
functions.  Provide a separate name for our assembly memcpy() and
memset() functions, and use that instead, thereby bypassing GCC's
ability to optimise these operations.

GCCs optimisation may introduce unaligned accesses which are invalid
for device mappings.

Signed-off-by: Russell King

ARM: fix lockdep unannotated irqs-off warning

2015-07-03T11:42:36+00:00

Wolfram Sang reported an unannotated irqs-off warning from lockdep:

WARNING: CPU: 0 PID: 282 at kernel/locking/lockdep.c:3557 check_flags+0x84/0x1f4()
DEBUG_LOCKS_WARN_ON(current->hardirqs_enabled)
CPU: 0 PID: 282 Comm: rcS Tainted: G        W 4.1.0-00002-g5b076054611833 #179
Hardware name: Generic Emma Mobile EV2 (Flattened Device Tree)
Backtrace:
[] (dump_backtrace) from [] (show_stack+0x18/0x1c)
 r6:c02dcc67 r5:00000009 r4:00000000 r3:00400000
[] (show_stack) from [] (dump_stack+0x20/0x28)
[] (dump_stack) from [] (warn_slowpath_common+0x8c/0xb4)
[] (warn_slowpath_common) from [] (warn_slowpath_fmt+0x38/0x40)
 r8:c780f470 r7:00000000 r6:00000000 r5:c03b0570 r4:c0b7ec04
[] (warn_slowpath_fmt) from [] (check_flags+0x84/0x1f4)
 r3:c02e13d8 r2:c02dceaa
[] (check_flags) from [] (lock_acquire+0x4c/0xbc)
 r5:00000000 r4:60000193
[] (lock_acquire) from [] (_raw_spin_lock+0x34/0x44)
 r9:000a8d5c r8:00000001 r7:c7806000 r6:c780f460 r5:c03b06a0 r4:c780f460
[] (_raw_spin_lock) from [] (handle_fasteoi_irq+0x20/0x11c)
 r4:c780f400
[] (handle_fasteoi_irq) from [] (generic_handle_irq+0x28/0x38)
 r6:00000000 r5:c03b038c r4:00000012 r3:c005a8ac
[] (generic_handle_irq) from [] (__handle_domain_irq+0x88/0xa8)
 r4:00000000 r3:00000026
[] (__handle_domain_irq) from [] (gic_handle_irq+0x40/0x58)
 r8:10c5347d r7:10c5347d r6:c35b1fb0 r5:c03a6304 r4:c8802000 r3:c35b1fb0
[] (gic_handle_irq) from [] (__irq_usr+0x48/0x60)
Exception stack(0xc35b1fb0 to 0xc35b1ff8)
1fa0:                                     00000061 00000000 000ab736 00000066
1fc0: 00000061 000aa1f0 000a8d54 000a8d54 000a8d88 000a8d5c 000a8cc8 000a8d68
1fe0: 72727272 bef8a528 000398c0 00031334 20000010 ffffffff
 r6:ffffffff r5:20000010 r4:00031334 r3:00000061
---[ end trace cb88537fdc8fa202 ]---
possible reason: unannotated irqs-off.
irq event stamp: 769
hardirqs last  enabled at (769): [] ret_fast_syscall+0x2c/0x54
hardirqs last disabled at (768): [] ret_fast_syscall+0xc/0x54
softirqs last  enabled at (0): [] copy_process.part.65+0x2e8/0x11dc
softirqs last disabled at (0): [<  (null)>]   (null)

His kernel configuration had:
CONFIG_PROVE_LOCKING=y
CONFIG_TRACE_IRQFLAGS=y
but no IRQSOFF_TRACER, which means entry from userspace can result in the
kernel seeing IRQs off without being notified of that change of state.
Change the IRQSOFF ifdef in the usr_entry macro to TRACE_IRQFLAGS instead.

Tested-by: Wolfram Sang 
Signed-off-by: Russell King

Merge tag 'module-misc-v4.1-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux

2015-07-02T18:07:27+00:00

Pull init.h/module.h fragility fixes from Paul Gortmaker:
 "Fixup various init.h misuses that are fragile wrt code moving to
  module.h

  What started as a removal of no longer required include 
  due to the earlier __cpuinit and __devinit removal led to the
  observation that some module specfic support was living in init.h
  itself, thus preventing the full removal from introducing compile
  regressions.

  This series includes a few final fixups needed prior to the relocation
  of the modular init code from  to .  These are
  things that weren't easily categorized into any of the other previous
  series categories already requested for pull.

  That said, each fixup branch (including this one) is independent and
  there are no ordering constraints.  Only the final code relocation
  (which is NOT in this pull) requires that all my cleanup branches be
  merged first"

* tag 'module-misc-v4.1-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux:
  tile: add init.h to usb.c to avoid compile failure
  arm: fix implicit #include  in entry asm.
  x86: replace __init_or_module with __init in non-modular vsmp_64.c