Skip to content
  1. Mar 01, 2013
  3. Feb 01, 2013
  5. Jan 31, 2013
    • Al Cooper's avatar
      MIPS: Function tracer: Fix broken function tracing · 58b69401
      Al Cooper authored 
      Function tracing is currently broken for all 32 bit MIPS platforms.
When tracing is enabled, the kernel immediately hangs on boot.
This is a result of commit b732d439


that changes the kernel/trace/Kconfig file so that is no longer
forces FRAME_POINTER when FUNCTION_TRACING is enabled.

MIPS frame pointers are generally considered to be useless because
they cannot be used to unwind the stack. Unfortunately the MIPS
function tracing code has bugs that are masked by the use of frame
pointers. This commit fixes the bugs so that MIPS frame pointers
don't need to be enabled.

The bugs are a result of the odd calling sequence used to call the trace
routine. This calling sequence is inserted into every traceable function
when the tracing CONFIG option is enabled. This sequence is generated
for 32bit MIPS platforms by the compiler via the "-pg" flag.

Part of the sequence is "addiu sp,sp,-8" in the delay slot after every
call to the trace routine "_mcount" (some legacy thing where 2 arguments
used to be pushed on the stack). The _mcount routine is expected to
adjust the sp by +8 before returning.  So when not disabled, the original
jalr and addiu will be there, so _mcount has to adjust sp.

The problem is that when tracing is disabled for a function, the
"jalr _mcount" instruction is replaced with a nop, but the
"addiu sp,sp,-8" is still executed and the stack pointer is left
trashed. When frame pointers are enabled the problem is masked
because any access to the stack is done through the frame
pointer and the stack pointer is restored from the frame pointer when
the function returns.

This patch writes two nops starting at the address of the "jalr _mcount"
instruction whenever tracing is disabled. This means that the
"addiu sp,sp.-8" will be converted to a nop along with the "jalr".  When
disabled, there will be two nops.

This is SMP safe because the first time this happens is during
ftrace_init() which is before any other processor has been started.
Subsequent calls to enable/disable tracing when other CPUs ARE running
will still be safe because the enable will only change the first nop
to a "jalr" and the disable, while writing 2 nops, will only be changing
the "jalr". This patch also stops using stop_machine() to call the
tracer enable/disable routines and calls them directly because the
routines are SMP safe.

When the kernel first boots we have to be able to handle the gcc
generated jalr, addui sequence until ftrace_init gets a chance to run
and change the sequence. At this point mcount just adjusts the stack
and returns. When ftrace_init runs, we convert the jalr/addui to nops.
Then whenever tracing is enabled we convert the first nop to a "jalr
mcount+8". The mcount+8 entry point skips the stack adjust.

[ralf@linux-mips.org: Folded in  Steven Rostedt's build fix.]

Signed-off-by: default avatarAl Cooper <alcooperx@gmail.com>
Cc: rostedt@goodmis.org
Cc: ddaney.cavm@gmail.com
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/4806/
Patchwork: https://patchwork.linux-mips.org/patch/4841/


Signed-off-by: default avatarRalf Baechle <ralf@linux-mips.org>
      58b69401
    • Sebastian Hesselbarth's avatar
      ARM: dove: cleanup includes · b3af7a1f
      Sebastian Hesselbarth authored 
      

This patch cleans unneccessary includes and reorders the remaining
includes in common dove code.

Signed-off-by: default avatarSebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Signed-off-by: default avatarJason Cooper <jason@lakedaemon.net>
      b3af7a1f
    • Jason Cooper's avatar
      ARM: kirkwood: nsa310: cleanup includes and unneeded code · 7e5fa2f0
      Jason Cooper authored 
      

After removing the unneeded linux/i2c.h, linux/of.h was needed for
of_machine_is_compatible().  i2c.h had included of.h.

Signed-off-by: default avatarJason Cooper <jason@lakedaemon.net>
      7e5fa2f0
    • Steven Rostedt's avatar
      mips: Move __virt_addr_valid() to a place for MIPS 64 · 196897a2
      Steven Rostedt authored 
      Commit d3ce8843

 "MIPS: Fix modpost error in modules attepting to use
virt_addr_valid()" moved __virt_addr_valid() from a macro in a header
file to a function in ioremap.c. But ioremap.c is only compiled for MIPS
32, and not for MIPS 64.

When compiling for my yeeloong2, which supposedly supports hibernation,
which compiles kernel/power/snapshot.c which calls virt_addr_valid(), I
got this error:

  LD      init/built-in.o
kernel/built-in.o: In function `memory_bm_free':
snapshot.c:(.text+0x4c9c4): undefined reference to `__virt_addr_valid'
snapshot.c:(.text+0x4ca58): undefined reference to `__virt_addr_valid'
kernel/built-in.o: In function `snapshot_write_next':
(.text+0x4e44c): undefined reference to `__virt_addr_valid'
kernel/built-in.o: In function `snapshot_write_next':
(.text+0x4e890): undefined reference to `__virt_addr_valid'
make[1]: *** [vmlinux] Error 1
make: *** [sub-make] Error 2

I suspect that __virt_addr_valid() is fine for mips 64. I moved it to
mmap.c such that it gets compiled for mips 64 and 32.

Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/4842/


Signed-off-by: default avatarRalf Baechle <ralf@linux-mips.org>
      196897a2
    • Jayachandran C's avatar
      MIPS: Netlogic: Fix UP compilation on XLR · 26f5ae86
      Jayachandran C authored 
      The commit 2a37b1ae

 "MIPS: Netlogic: Move from u32 cpumask to cpumask_t"
breaks uniprocessor compilation on XLR with:

arch/mips/netlogic/xlr/setup.c: In function 'prom_init':
arch/mips/netlogic/xlr/setup.c:196:6: error: unused variable 'i'

Fix by defining 'i' only when CONFIG_SMP is defined.

Signed-off-by: default avatarJayachandran C <jchandra@broadcom.com>
Patchwork: http://patchwork.linux-mips.org/patch/4760/


Signed-off-by: default avatarJohn Crispin <blogic@openwrt.org>
Signed-off-by: default avatarRalf Baechle <ralf@linux-mips.org>
      26f5ae86
    • Gabor Juhos's avatar
      MIPS: AR71xx: Fix AR71XX_PCI_MEM_SIZE · fe950df7
      Gabor Juhos authored 
      

The base address of the PCI memory is 0x10000000 and the base address of the
PCI configuration space is 0x17000000 on the AR71xx SoCs.

The AR71XX_PCI_MEM_SIZE is defined as 0x08000000 which is wrong because that
overlaps with the configuration space.  This patch fixes the value of the
AR71XX_PCI_MEM_SIZE constant, in order to avoid this resource conflicts.

Signed-off-by: default avatarGabor Juhos <juhosg@openwrt.org>
Patchwork: http://patchwork.linux-mips.org/patch/4873/


Signed-off-by: default avatarJohn Crispin <blogic@openwrt.org>
Signed-off-by: default avatarRalf Baechle <ralf@linux-mips.org>
      fe950df7
    • Gabor Juhos's avatar
      MIPS: AR724x: Fix AR724X_PCI_MEM_SIZE · 4c960910
      Gabor Juhos authored 
      

The base address of the PCI memory is
0x10000000 and the base address of the
PCI configuration space is 0x14000000
on the AR724x SoCs.

The AR724X_PCI_MEM_SIZE is defined as
0x08000000 which is wrong because that
overlaps  with the configuration space.

The patch fixes the value of the
AR724X_PCI_MEM_SIZE constant, in order
to avoid this resource conflicts.

Signed-off-by: default avatarGabor Juhos <juhosg@openwrt.org>
Patchwork: http://patchwork.linux-mips.org/patch/4872/


Signed-off-by: default avatarJohn Crispin <blogic@openwrt.org>
Signed-off-by: default avatarRalf Baechle <ralf@linux-mips.org>
      4c960910
    • John Crispin's avatar
      MIPS: Lantiq: Fix cp0_perfcount_irq mapping · 79d61a04
      John Crispin authored 
      The introduction of the OF support broke the cp0_perfcount_irq mapping. This
resulted in oprofile not working anymore.

Offending commit is :

commit 3645da02


Author: John Crispin <blogic@openwrt.org>
Date:   Tue Apr 17 10:18:32 2012 +0200

OF: MIPS: lantiq: implement irq_domain support

Signed-off-by: default avatarConor O'Gorman <i@conorogorman.net>
Signed-off-by: default avatarJohn Crispin <blogic@openwrt.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/4875/


Signed-off-by: default avatarRalf Baechle <ralf@linux-mips.org>
      79d61a04
    • Jason Gunthorpe's avatar
      ARM: Kirkwood: Support basic hotplug for PCI-E · b73690c8
      Jason Gunthorpe authored 
      

Unconditionally register the PCI-E bus, even if the link is currently
down. When the link is brought up the bus can be scanned through
/sys/bus/pci/rescan or otherwise. Since the HW has no interrupt for
link up, userspace will have to take care of the timing.

An earlier version of this was contingent on CONFIG_HOTPLUG, but
that is being removed from the kernel.

This also fixes printing the link up/down message to be displayed
on one line (structured logging broke this?)

Signed-off-by: default avatarJason Gunthorpe <jgunthorpe@obsidianresearch.com>
Signed-off-by: default avatarJason Cooper <jason@lakedaemon.net>
      b73690c8
    • Matt Fleming's avatar
      efi: Make 'efi_enabled' a function to query EFI facilities · 83e68189
      Matt Fleming authored 
      Originally 'efi_enabled' indicated whether a kernel was booted from
EFI firmware. Over time its semantics have changed, and it now
indicates whether or not we are booted on an EFI machine with
bit-native firmware, e.g. 64-bit kernel with 64-bit firmware.

The immediate motivation for this patch is the bug report at,

    https://bugs.launchpad.net/ubuntu-cdimage/+bug/1040557

which details how running a platform driver on an EFI machine that is
designed to run under BIOS can cause the machine to become
bricked. Also, the following report,

    https://bugzilla.kernel.org/show_bug.cgi?id=47121



details how running said driver can also cause Machine Check
Exceptions. Drivers need a new means of detecting whether they're
running on an EFI machine, as sadly the expression,

    if (!efi_enabled)

hasn't been a sufficient condition for quite some time.

Users actually want to query 'efi_enabled' for different reasons -
what they really want access to is the list of available EFI
facilities.

For instance, the x86 reboot code needs to know whether it can invoke
the ResetSystem() function provided by the EFI runtime services, while
the ACPI OSL code wants to know whether the EFI config tables were
mapped successfully. There are also checks in some of the platform
driver code to simply see if they're running on an EFI machine (which
would make it a bad idea to do BIOS-y things).

This patch is a prereq for the samsung-laptop fix patch.

Cc: David Airlie <airlied@linux.ie>
Cc: Corentin Chary <corentincj@iksaif.net>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Olof Johansson <olof@lixom.net>
Cc: Peter Jones <pjones@redhat.com>
Cc: Colin Ian King <colin.king@canonical.com>
Cc: Steve Langasek <steve.langasek@canonical.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Konrad Rzeszutek Wilk <konrad@kernel.org>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: <stable@vger.kernel.org>
Signed-off-by: default avatarMatt Fleming <matt.fleming@intel.com>
Signed-off-by: default avatarH. Peter Anvin <hpa@linux.intel.com>
      83e68189
  7. Jan 30, 2013
  9. Jan 29, 2013
    • Tiejun Chen's avatar
      powerpc: Max next_tb to prevent from replaying timer interrupt · 689dfa89
      Tiejun Chen authored 
      

With lazy interrupt, we always call __check_irq_replaysome with
decrementers_next_tb to check if we need to replay timer interrupt.
So in hotplug case we also need to set decrementers_next_tb as MAX
to make sure __check_irq_replay don't replay timer interrupt
when return as we expect, otherwise we'll trap here infinitely.

Signed-off-by: default avatarTiejun Chen <tiejun.chen@windriver.com>
Signed-off-by: default avatarBenjamin Herrenschmidt <benh@kernel.crashing.org>
      689dfa89
    • Cong Ding's avatar
      powerpc: kernel/kgdb.c: Fix memory leakage · fefd9e6f
      Cong Ding authored 
      

the variable backup_current_thread_info isn't freed before existing the
function.

Signed-off-by: default avatarCong Ding <dinggnu@gmail.com>
Signed-off-by: default avatarBenjamin Herrenschmidt <benh@kernel.crashing.org>
      fefd9e6f
    • Tiejun Chen's avatar
      powerpc/book3e: Disable interrupt after preempt_schedule_irq · 572177d7
      Tiejun Chen authored 
      

In preempt case current arch_local_irq_restore() from
preempt_schedule_irq() may enable hard interrupt but we really
should disable interrupts when we return from the interrupt,
and so that we don't get interrupted after loading SRR0/1.

Signed-off-by: default avatarTiejun Chen <tiejun.chen@windriver.com>
CC: <stable@vger.kernel.org>
Signed-off-by: default avatarBenjamin Herrenschmidt <benh@kernel.crashing.org>
      572177d7
    • Carl E. Love's avatar
      powerpc/oprofile: Fix error in oprofile power7_marked_instr_event() function · 46ed7a76
      Carl E. Love authored 
      

The calculation for the left shift of the mask OPROFILE_PM_PMCSEL_MSK has an
error.  The calculation is should be to shift left by (max_cntrs - cntr) times
the width of the pmsel field width.  However, the #define OPROFILE_MAX_PMC_NUM
was used instead of OPROFILE_PMSEL_FIELD_WIDTH.  This patch fixes the
calculation.

Signed-off-by: default avatarCarl Love <cel@us.ibm.com>
Acked-by: default avatarPaul Mackerras <paulus@samba.org>
Signed-off-by: default avatarBenjamin Herrenschmidt <benh@kernel.crashing.org>
      46ed7a76
    • Steven Rostedt's avatar
      powerpc/pasemi: Fix crash on reboot · 72640d88
      Steven Rostedt authored 
      commit f96972f2

 "kernel/sys.c: call disable_nonboot_cpus() in
kernel_restart()"

added a call to disable_nonboot_cpus() on kernel_restart(), which tries
to shutdown all the CPUs except the first one. The issue with the PA
Semi, is that it does not support CPU hotplug.

When the call is made to __cpu_down(), it calls the notifiers
CPU_DOWN_PREPARE, and then tries to take the CPU down.

One of the notifiers to the CPU hotplug code, is the cpufreq. The
DOWN_PREPARE will call __cpufreq_remove_dev() which calls
cpufreq_driver->exit. The PA Semi exit handler unmaps regions of I/O
that is used by an interrupt that goes off constantly
(system_reset_common, but it goes off during normal system operations
too). I'm not sure exactly what this interrupt does.

Running a simple function trace, you can see it goes off quite a bit:

# tracer: function
#
#           TASK-PID    CPU#    TIMESTAMP  FUNCTION
#              | |       |          |         |
          <idle>-0     [001]  1558.859363: .pasemi_system_reset_exception <-.system_reset_exception
          <idle>-0     [000]  1558.860112: .pasemi_system_reset_exception <-.system_reset_exception
          <idle>-0     [000]  1558.861109: .pasemi_system_reset_exception <-.system_reset_exception
          <idle>-0     [001]  1558.861361: .pasemi_system_reset_exception <-.system_reset_exception
          <idle>-0     [000]  1558.861437: .pasemi_system_reset_exception <-.system_reset_exception

When the region is unmapped, the system crashes with:

Disabling non-boot CPUs ...
Error taking CPU1 down: -38
Unable to handle kernel paging request for data at address 0xd0000800903a0100
Faulting instruction address: 0xc000000000055fcc
Oops: Kernel access of bad area, sig: 11 [#1]
PREEMPT SMP NR_CPUS=64 NUMA PA Semi PWRficient
Modules linked in: shpchp
NIP: c000000000055fcc LR: c000000000055fb4 CTR: c0000000000df1fc
REGS: c0000000012175d0 TRAP: 0300   Not tainted  (3.8.0-rc4-test-dirty)
MSR: 9000000000009032 <SF,HV,EE,ME,IR,DR,RI>  CR: 24000088  XER: 00000000
SOFTE: 0
DAR: d0000800903a0100, DSISR: 42000000
TASK = c0000000010e9008[0] 'swapper/0' THREAD: c000000001214000 CPU: 0
GPR00: d0000800903a0000 c000000001217850 c0000000012167e0 0000000000000000
GPR04: 0000000000000000 0000000000000724 0000000000000724 0000000000000000
GPR08: 0000000000000000 0000000000000000 0000000000000001 0000000000a70000
GPR12: 0000000024000080 c00000000fff0000 ffffffffffffffff 000000003ffffae0
GPR16: ffffffffffffffff 0000000000a21198 0000000000000060 0000000000000000
GPR20: 00000000008fdd35 0000000000a21258 000000003ffffaf0 0000000000000417
GPR24: 0000000000a226d0 c000000000000000 0000000000000000 0000000000000000
GPR28: c00000000138b358 0000000000000000 c000000001144818 d0000800903a0100
NIP [c000000000055fcc] .set_astate+0x5c/0xa4
LR [c000000000055fb4] .set_astate+0x44/0xa4
Call Trace:
[c000000001217850] [c000000000055fb4] .set_astate+0x44/0xa4 (unreliable)
[c0000000012178f0] [c00000000005647c] .restore_astate+0x2c/0x34
[c000000001217980] [c000000000054668] .pasemi_system_reset_exception+0x6c/0x88
[c000000001217a00] [c000000000019ef0] .system_reset_exception+0x48/0x84
[c000000001217a80] [c000000000001e40] system_reset_common+0x140/0x180

Signed-off-by: default avatarBenjamin Herrenschmidt <benh@kernel.crashing.org>
      72640d88
    • Li Zhong's avatar
      powerpc: Fix MAX_STACK_TRACE_ENTRIES too low warning for ppc32 · 41d82bdb
      Li Zhong authored 
      This patch fixes MAX_STACK_TRACE_ENTRIES too low warning for ppc32,
which is similar to commit 12660b17

.

Reported-by: default avatarChristian Kujau <lists@nerdbynature.de>
Signed-off-by: default avatarLi Zhong <zhong@linux.vnet.ibm.com>
Tested-by: default avatarChristian Kujau <lists@nerdbynature.de>
Signed-off-by: default avatarBenjamin Herrenschmidt <benh@kernel.crashing.org>
      41d82bdb
  11. Jan 28, 2013