On the syscall tracing path, we call out to secure_computing() to allow
seccomp to check the syscall number being attempted. As part of this, a
SIGTRAP may be sent to the tracer and the syscall could be re-written by
a subsequent SET_SYSCALL ptrace request. Unfortunately, this new syscall
is ignored by the current code unless TIF_SYSCALL_TRACE is also set on
the current thread.
This patch slightly reworks the enter path of the syscall tracing code
so that we always reload the syscall number from
current_thread_info()->syscall after the potential ptrace traps.
Acked-by: Kees Cook <keescook@chromium.org>
Tested-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Avoid conflicts with user mode usage of the same instructions, as with
Clang -ftrapv.
Change-Id: I12d1c6d8f94376bfd2503cb0be843d7e478fb6ea
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Since the smp call to stop the other cpus are handled in those
cpus in interrupt context, there's a potential for those smp
handlers to interrupt threads holding spin locks (such as the
one a mutex holds). This prevents those threads from ever
releasing their spin lock, so if the cpu doing the shutdown
is allowed to switch to another thread that tries to grab the
same lock/mutex, we could get into a deadlock (the spin lock
call is called with preemption disabled in the mutex lock code).
To avoid that possibility, disable preemption before doing the
smp_send_stop().
Change-Id: I7976c5382d7173fcb3cd14da8cc5083d442b2544
Signed-off-by: Mike J. Chen <mjchen@google.com>
When PowerDown was requested at the same time as ProgBit, the
formatter flush command that follows could get stuck.
Change-Id: Iafb665f61f055819e64ca1dcb60398c656f593e4
Signed-off-by: Arve Hjønnevåg <arve@android.com>
Without this change a saw an 18% increase in idle power consumption
on one deivce when trace support is compiled into the kernel. Now
I see the same increase only when tracing.
Change-Id: I21bb5ecf1b7d29ce3790ceeb5323409cc22d5a3b
Signed-off-by: Arve Hjønnevåg <arve@android.com>
If more than one ETM or PTM are present, configure all of them
and enable the formatter in the ETB. This allows tracing on dual
core systems (e.g. omap4).
Change-Id: I028657d5cf2bee1b23f193d4387b607953b35888
Signed-off-by: Arve Hjønnevåg <arve@android.com>
On some SOCs the read and write pointer are reset when the chip
resets, but the trace buffer content is preserved. If the status
bits indicates that the buffer is empty and we have never started
tracing, assume the buffer is full instead. This can be useful
if the system rebooted from a watchdog reset.
Change-Id: Iaf21c2c329c6059004ee1d38e3dfff66d7d28029
Signed-off-by: Arve Hjønnevåg <arve@android.com>
It is not safe to call etm_lock or etb_lock without holding the
mutex since another thread may also have unlocked the registers.
Also add some missing checks for valid etb_regs in the etm sysfs
entries.
Change-Id: I939f76a6ea7546a8fc0d4ddafa2fd2b6f38103bb
Signed-off-by: Arve Hjønnevåg <arve@android.com>
The old code enabled data tracing, but did not configure the
range. We now configure it to trace all data addresses by default,
and add a trace_data_range attribute to change the range or disable
data tracing.
Change-Id: I9d04e3e1ea0d0b4d4d5bcb93b1b042938ad738b2
Signed-off-by: Arve Hjønnevåg <arve@android.com>
Trace kernel text segment by default as before, allow tracing of other
ranges by writing a range to /sys/devices/etm/trace_range, or to trace
everything by writing 0 0.
Change-Id: Ibb734ca820fedf79560b20536247f1e1700cdc71
Signed-off-by: Arve Hjønnevåg <arve@android.com>
If the write address was at the end of the buffer, toggling the trace
capture bit would set the RAM-full status instead of clearing it, and
if any of the stop bits in the formatter is set toggling the trace
capture bit may not do anything.
Instead use the read position to find out if the data has already
been returned.
This also fixes the read function so it works when the trace buffer is
larger than the buffer passed in from user space. The old version
would reset the trace buffer pointers after every read, so the second
call to read would always return 0.
Change-Id: I75256abe2556adfd66fd5963e46f9e84ae4645e1
Signed-off-by: Arve Hjønnevåg <arve@android.com>
On some systems kernel code is considered secure, and this code
already limits tracing to the kernel text segment which results
in no trace data.
Change-Id: I098a0753e874859446d098e1ee209f67fc13cd5d
Signed-off-by: Arve Hjønnevåg <arve@android.com>
If clk_get fail, assume the etb does not need a separate clock.
Change-Id: Ia0bf3f5391e94a60ea45876aa7afc8a88a7ec3bf
Signed-off-by: Arve Hjønnevåg <arve@android.com>
This patch implements CONFIG_DEBUG_RODATA, allowing
the kernel text section to be marked read-only in
order to catch bugs that write over the kernel. This
requires mapping the kernel code, plus up to 4MB, using
pages instead of sections, which can increase TLB
pressure.
The kernel is normally mapped using 1MB section entries
in the first level page table, and the first level page
table is copied into every mm. This prevents marking
the kernel text read-only, because the 1MB section
entries are too large granularity to separate the init
section, which is reused as read-write memory after
init, and the kernel text section. Also, the top level
page table for every process would need to be updated,
which is not possible to do safely and efficiently on SMP.
To solve both problems, allow alloc_init_pte to overwrite
an existing section entry with a fully-populated second
level page table. When CONFIG_DEBUG_RODATA is set, all
the section entries that overlap the kernel text section
will be replaced with page mappings. The kernel always
uses a pair of 2MB-aligned 1MB sections, so up to 2MB
of memory before and after the kernel may end up page
mapped.
When the top level page tables are copied into each
process the second level page tables are not copied,
leaving a single second level page table that will
affect all processes on all cpus. To mark a page
read-only, the second level page table is located using
the pointer in the first level page table for the
current process, and the supervisor RO bit is flipped
atomically. Once all pages have been updated, all TLBs
are flushed to ensure the changes are visible on all
cpus.
If CONFIG_DEBUG_RODATA is not set, the kernel will be
mapped using the normal 1MB section entries.
Change-Id: I94fae337f882c2e123abaf8e1082c29cd5d483c6
Signed-off-by: Colin Cross <ccross@android.com>
Based on a rough patch by frank.rowand@am.sony.com
Since ARM doesn't have an NMI (fiq's are not always available),
send an IPI to all other CPUs (current cpu prints the stack directly)
to capture a backtrace.
Change-Id: I8b163c8cec05d521b433ae133795865e8a33d4e2
Signed-off-by: Dima Zavin <dima@android.com>
If the console_lock was held while the system was rebooted, the messages
in the temporary logbuffer would not have propogated to all the console
drivers.
This force releases the console lock if it failed to be acquired.
Change-Id: I193dcf7b968be17966833e50b8b8bc70d5d9fe89
Signed-off-by: Dima Zavin <dima@android.com>
This is extremely useful in diagnosing remote crashes, and is based heavily
on original work by <md@google.com>.
Signed-off-by: San Mehat <san@google.com>
Cc: Michael Davidson <md@google.com>
[ARM] process: Use uber-safe probe_kernel_address() to read mem when dumping.
This prevents the dump from taking pagefaults / external aborts.
Signed-off-by: San Mehat <san@google.com>
Due to recent changes and expecations of proper cpu bindings, there are
now cases for many of the in-tree devicetrees where a WARN() will hit
on boot due to badly formatted /cpus nodes.
Downgrade this to a pr_warn() to be less alarmist, since it's not a
new problem.
Tested on Arndale, Cubox, Seaboard and Panda ES. Panda hits the WARN
without this, the others do not.
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The __cpu_logical_map array is statically initialized to 0, which is a valid
MPIDR value. To prevent issues with the current implementation, this patch
defines an MPIDR_INVALID value, and statically initializes the
__cpu_logical_map[] array to it. Entries in the arm_dt_init_cpu_maps()
tmp_map array used to stash DT reg properties while parsing DT are initialized
with the MPIDR_INVALID value as well for consistency.
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The introduction of the cpu-map topology node in the cpus node implies
that cpus node might have children that are not cpu nodes. The DT
parsing code needs updating otherwise it would check for cpu nodes
properties in nodes that are not required to contain them, resulting
in warnings that have no bearing on bindings defined in the dts source file.
Cc: <stable@vger.kernel.org> [3.8+]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Add comments to machine_shutdown()/halt()/power_off()/restart() that
describe their purpose and/or requirements re: CPUs being active/not.
In machine_shutdown(), replace the call to smp_send_stop() with a call to
disable_nonboot_cpus(). This completely disables all but one CPU, thus
satisfying the requirement that only a single CPU be active for kexec.
Adjust Kconfig dependencies for this change.
In machine_halt()/power_off()/restart(), call smp_send_stop() directly,
rather than via machine_shutdown(); these functions don't need to
completely de-activate all CPUs using hotplug, but rather just quiesce
them.
Remove smp_kill_cpus(), and its call from smp_send_stop().
smp_kill_cpus() was indirectly calling smp_ops.cpu_kill() without calling
smp_ops.cpu_die() on the target CPUs first. At least some implementations
of smp_ops had issues with this; it caused cpu_kill() to hang on Tegra,
for example. Since smp_send_stop() is only used for shutdown, halt, and
power-off, there is no need to attempt any kind of CPU hotplug here.
Adjust Kconfig to reflect that machine_shutdown() (and hence kexec)
relies upon disable_nonboot_cpus(). However, this alone doesn't guarantee
that hotplug will work, or even that hotplug is implemented for a
particular piece of HW that a multi-platform zImage runs on. Hence, add
error-checking to machine_kexec() to determine whether it did work.
Suggested-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Tested-by: Zhangfei Gao <zhangfei.gao@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The cpu_topology symbol is required by any driver using the topology
interfaces, which leads to a couple of build errors:
ERROR: "cpu_topology" [drivers/net/ethernet/sfc/sfc.ko] undefined!
ERROR: "cpu_topology" [drivers/cpufreq/arm_big_little.ko] undefined!
ERROR: "cpu_topology" [drivers/block/mtip32xx/mtip32xx.ko] undefined!
The obvious solution is to export this symbol.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: stable@vger.kernel.org
Cc: Nicolas Pitre <nico@linaro.org>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Pull ARM fixes from Russell King:
"Just three this time, all really quite small"
* 'fixes' of git://git.linaro.org/people/rmk/linux-arm:
ARM: 7729/1: vfp: ensure VFP_arch is non-zero when VFP is not supported
ARM: 7727/1: remove the .vm_mm value from gate_vma
ARM: 7723/1: crypto: sha1-armv4-large.S: fix SP handling
If one reads /proc/$PID/smaps, the mmap_sem belonging to the
address space of the task being examined is locked for reading.
All the pages of the vmas belonging to the task's address space
are then walked with this lock held.
If a gate_vma is present in the architecture, it too is examined
by the fs/proc/task_mmu.c code. As gate_vma doesn't belong to the
address space of the task though, its pages are not walked.
A recent cleanup (commit f6604efe) of the gate_vma initialisation
code set the vm_mm value to &init_mm. Unfortunately a non-NULL
vm_mm value in the gate_vma will cause the task_mmu code to attempt
to walk the pages of the gate_vma (with no mmap-sem lock held). If
one enables Transparent Huge Page support and vm debugging, this
will then cause OOPses as pmd_trans_huge_lock is called without
mmap_sem being locked.
This patch removes the .vm_mm value from gate_vma, restoring the
original behaviour of the task_mmu code.
Signed-off-by: Steve Capper <steve.capper@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Before f7b861b7a6 ("arm: Use generic idle loop") ARM would kill the
CPU within the rcu idle section. Now that the rcu_idle_enter()/exit()
pair have been pushed lower down in the idle loop this is no longer true
and so using RCU_NONIDLE here is no longer necessary and also harmful
because RCU is not actually idle at this point.
Cc: Russell King <linux@arm.linux.org.uk>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* late/fixes:
ARM: OMAP2+: Fix unmet direct dependencies for SERIAL_OMAP
ARM: ux500: always select ABX500_CORE
ARM: SIRF: select SMP_ON_UP only on SMP builds
ARM: SPEAr: conditionalize l2x0 support
ARM: imx: build CPU suspend code only when needed
ARM: OMAP: build SMP code only for OMAP4/5
ARM: tegra: Tegra114 needs CPU_FREQ_TABLE
ARM: default machine descriptor for multiplatform
Signed-off-by: Olof Johansson <olof@lixom.net>
Pull ARM SoC late cleanups from Arnd Bergmann:
"These are cleanups and smaller changes that either depend on earlier
feature branches or came in late during the development cycle. We
normally try to get all cleanups early, so these are the exceptions:
- A follow-up on the clocksource reworks, hopefully the last time we
need to merge clocksource subsystem changes through arm-soc.
A first set of patches was part of the original 3.10 arm-soc
cleanup series because of interdependencies with timer drivers now
moved out of arch/arm.
- Migrating the SPEAr13xx platform away from using auxdata for DMA
channel descriptions towards using information in device tree,
based on the earlier SPEAr multiplatform series
- A few follow-ups on the Atmel SAMA5 support and other changes for
Atmel at91 based on the larger at91 reworks.
- Moving the armada irqchip implementation to drivers/irqchip
- Several OMAP cleanups following up on the larger series already
merged in 3.10."
* tag 'cleanup-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (50 commits)
ARM: OMAP4: change the device names in usb_bind_phy
ARM: OMAP2+: Fix mismerge for timer.c between ff931c82 and da4a686a
ARM: SPEAr: conditionalize SMP code
ARM: arch_timer: Silence debug preempt warnings
ARM: OMAP: remove unused variable
serial: amba-pl011: fix !CONFIG_DMA_ENGINE case
ata: arasan: remove the need for platform_data
ARM: at91/sama5d34ek.dts: remove not needed compatibility string
ARM: at91: dts: add MCI DMA support
ARM: at91: dts: add i2c dma support
ARM: at91: dts: set #dma-cells to the correct value
ARM: at91: suspend both memory controllers on at91sam9263
irqchip: armada-370-xp: slightly cleanup irq controller driver
irqchip: armada-370-xp: move IRQ handler to avoid forward declaration
irqchip: move IRQ driver for Armada 370/XP
ARM: mvebu: move L2 cache initialization in init_early()
devtree: add binding documentation for sp804
ARM: integrator-cp: convert use CLKSRC_OF for timer init
ARM: versatile: use OF init for sp804 timer
ARM: versatile: add versatile dtbs to dtbs target
...
There is no reason to keep the clksrc cleanups separate from the
other cleanups, and this resolves some merge conflicts.
Conflicts:
arch/arm/mach-spear/spear13xx.c
drivers/irqchip/Makefile
Pull kvm updates from Gleb Natapov:
"Highlights of the updates are:
general:
- new emulated device API
- legacy device assignment is now optional
- irqfd interface is more generic and can be shared between arches
x86:
- VMCS shadow support and other nested VMX improvements
- APIC virtualization and Posted Interrupt hardware support
- Optimize mmio spte zapping
ppc:
- BookE: in-kernel MPIC emulation with irqfd support
- Book3S: in-kernel XICS emulation (incomplete)
- Book3S: HV: migration fixes
- BookE: more debug support preparation
- BookE: e6500 support
ARM:
- reworking of Hyp idmaps
s390:
- ioeventfd for virtio-ccw
And many other bug fixes, cleanups and improvements"
* tag 'kvm-3.10-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (204 commits)
kvm: Add compat_ioctl for device control API
KVM: x86: Account for failing enable_irq_window for NMI window request
KVM: PPC: Book3S: Add API for in-kernel XICS emulation
kvm/ppc/mpic: fix missing unlock in set_base_addr()
kvm/ppc: Hold srcu lock when calling kvm_io_bus_read/write
kvm/ppc/mpic: remove users
kvm/ppc/mpic: fix mmio region lists when multiple guests used
kvm/ppc/mpic: remove default routes from documentation
kvm: KVM_CAP_IOMMU only available with device assignment
ARM: KVM: iterate over all CPUs for CPU compatibility check
KVM: ARM: Fix spelling in error message
ARM: KVM: define KVM_ARM_MAX_VCPUS unconditionally
KVM: ARM: Fix API documentation for ONE_REG encoding
ARM: KVM: promote vfp_host pointer to generic host cpu context
ARM: KVM: add architecture specific hook for capabilities
ARM: KVM: perform HYP initilization for hotplugged CPUs
ARM: KVM: switch to a dual-step HYP init code
ARM: KVM: rework HYP page table freeing
ARM: KVM: enforce maximum size for identity mapped code
ARM: KVM: move to a KVM provided HYP idmap
...
Pull ARM updates from Russell King:
"The major items included in here are:
- MCPM, multi-cluster power management, part of the infrastructure
required for ARMs big.LITTLE support.
- A rework of the ARM KVM code to allow re-use by ARM64.
- Error handling cleanups of the IS_ERR_OR_NULL() madness and fixes
of that stuff for arch/arm
- Preparatory patches for Cortex-M3 support from Uwe Kleine-König.
There is also a set of three patches in here from Hugh/Catalin to
address freeing of inappropriate page tables on LPAE. You already
have these from akpm, but they were already part of my tree at the
time he sent them, so unfortunately they'll end up with duplicate
commits"
* 'for-linus' of git://git.linaro.org/people/rmk/linux-arm: (77 commits)
ARM: EXYNOS: remove unnecessary use of IS_ERR_VALUE()
ARM: IMX: remove unnecessary use of IS_ERR_VALUE()
ARM: OMAP: use consistent error checking
ARM: cleanup: OMAP hwmod error checking
ARM: 7709/1: mcpm: Add explicit AFLAGS to support v6/v7 multiplatform kernels
ARM: 7700/2: Make cpu_init() notrace
ARM: 7702/1: Set the page table freeing ceiling to TASK_SIZE
ARM: 7701/1: mm: Allow arch code to control the user page table ceiling
ARM: 7703/1: Disable preemption in broadcast_tlb*_a15_erratum()
ARM: mcpm: provide an interface to set the SMP ops at run time
ARM: mcpm: generic SMP secondary bringup and hotplug support
ARM: mcpm_head.S: vlock-based first man election
ARM: mcpm: Add baremetal voting mutexes
ARM: mcpm: introduce helpers for platform coherency exit/setup
ARM: mcpm: introduce the CPU/cluster power API
ARM: multi-cluster PM: secondary kernel entry code
ARM: cacheflush: add synchronization helpers for mixed cache state accesses
ARM: cpu hotplug: remove majority of cache flushing from platforms
ARM: smp: flush L1 cache in cpu_die()
ARM: tegra: remove tegra specific cpu_disable()
...
Pull ARM SoC cleanup from Olof Johansson:
"Here is a collection of cleanup patches. Among the pieces that stand
out are:
- The deletion of h720x platforms
- Split of at91 non-dt platforms to their own Kconfig file to keep
them separate
- General cleanups and refactoring of i.MX and MXS platforms
- Some restructuring of clock tables for OMAP
- Convertion of PMC driver for Tegra to dt-only
- Some renames of sunxi -> sun4i (Allwinner A10)
- ... plus a bunch of other stuff that I haven't mentioned"
* tag 'cleanup-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (119 commits)
ARM: i.MX: remove unused ARCH_* configs
ARM i.MX53: remove platform ahci support
ARM: sunxi: Rework the restart code
irqchip: sunxi: Rename sunxi to sun4i
irqchip: sunxi: Make use of the IRQCHIP_DECLARE macro
clocksource: sunxi: Rename sunxi to sun4i
clocksource: sunxi: make use of CLKSRC_OF
clocksource: sunxi: Cleanup the timer code
ARM: at91: remove trailing semicolon from macros
ARM: at91/setup: fix trivial typos
ARM: EXYNOS: remove "config EXYNOS_DEV_DRM"
ARM: EXYNOS: change the name of USB ohci header
ARM: SAMSUNG: Remove unnecessary code for dma
ARM: S3C24XX: Remove unused GPIO drive strength register definitions
ARM: OMAP4+: PM: Restore CPU power state to ON with clockdomain force wakeup method
ARM: S3C24XX: Removed unneeded dependency on CPU_S3C2412
ARM: S3C24XX: Removed unneeded dependency on CPU_S3C2410
ARM: S3C24XX: Removed unneeded dependency on ARCH_S3C24XX for boards
ARM: SAMSUNG: Fix typo "CONFIG_SAMSUNG_DEV_RTC"
ARM: S5P64X0: Fix typo "CONFIG_S5P64X0_SETUP_SDHCI"
...
Pull VFS updates from Al Viro,
Misc cleanups all over the place, mainly wrt /proc interfaces (switch
create_proc_entry to proc_create(), get rid of the deprecated
create_proc_read_entry() in favor of using proc_create_data() and
seq_file etc).
7kloc removed.
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (204 commits)
don't bother with deferred freeing of fdtables
proc: Move non-public stuff from linux/proc_fs.h to fs/proc/internal.h
proc: Make the PROC_I() and PDE() macros internal to procfs
proc: Supply a function to remove a proc entry by PDE
take cgroup_open() and cpuset_open() to fs/proc/base.c
ppc: Clean up scanlog
ppc: Clean up rtas_flash driver somewhat
hostap: proc: Use remove_proc_subtree()
drm: proc: Use remove_proc_subtree()
drm: proc: Use minor->index to label things, not PDE->name
drm: Constify drm_proc_list[]
zoran: Don't print proc_dir_entry data in debug
reiserfs: Don't access the proc_dir_entry in r_open(), r_start() r_show()
proc: Supply an accessor for getting the data from a PDE's parent
airo: Use remove_proc_subtree()
rtl8192u: Don't need to save device proc dir PDE
rtl8187se: Use a dir under /proc/net/r8180/
proc: Add proc_mkdir_data()
proc: Move some bits from linux/proc_fs.h to linux/{of.h,signal.h,tty.h}
proc: Move PDE_NET() to fs/proc/proc_net.c
...
Currently help message of /proc/sysrq-trigger highlights its
upper-case characters, like below:
SysRq : HELP : loglevel(0-9) reBoot Crash terminate-all-tasks(E)
memory-full-oom-kill(F) kill-all-tasks(I) ...
this would confuse user trigger sysrq by upper-case character, which is
inconsistent with the real lower-case character registed key.
This inconsistent help message will also lead more confused when
26 upper-case letters put into use in future.
This patch fix arm etm sysrq key: "etm-buffer-dump(v)"
(This patch also add "-" to separate each sysrq key help word,
instead of spaces)
Signed-off-by: zhangwei(Jovi) <jovi.zhangwei@huawei.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
show_regs() is inherently arch-dependent but it does make sense to print
generic debug information and some archs already do albeit in slightly
different forms. This patch introduces a generic function to print debug
information from show_regs() so that different archs print out the same
information and it's much easier to modify what's printed.
show_regs_print_info() prints out the same debug info as dump_stack()
does plus task and thread_info pointers.
* Archs which didn't print debug info now do.
alpha, arc, blackfin, c6x, cris, frv, h8300, hexagon, ia64, m32r,
metag, microblaze, mn10300, openrisc, parisc, score, sh64, sparc,
um, xtensa
* Already prints debug info. Replaced with show_regs_print_info().
The printed information is superset of what used to be there.
arm, arm64, avr32, mips, powerpc, sh32, tile, unicore32, x86
* s390 is special in that it used to print arch-specific information
along with generic debug info. Heiko and Martin think that the
arch-specific extra isn't worth keeping s390 specfic implementation.
Converted to use the generic version.
Note that now all archs print the debug info before actual register
dumps.
An example BUG() dump follows.
kernel BUG at /work/os/work/kernel/workqueue.c:4841!
invalid opcode: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.9.0-rc1-work+ #7
Hardware name: empty empty/S3992, BIOS 080011 10/26/2007
task: ffff88007c85e040 ti: ffff88007c860000 task.ti: ffff88007c860000
RIP: 0010:[<ffffffff8234a07e>] [<ffffffff8234a07e>] init_workqueues+0x4/0x6
RSP: 0000:ffff88007c861ec8 EFLAGS: 00010246
RAX: ffff88007c861fd8 RBX: ffffffff824466a8 RCX: 0000000000000001
RDX: 0000000000000046 RSI: 0000000000000001 RDI: ffffffff8234a07a
RBP: ffff88007c861ec8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffffffff8234a07a
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff88007dc00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: ffff88015f7ff000 CR3: 00000000021f1000 CR4: 00000000000007f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Stack:
ffff88007c861ef8 ffffffff81000312 ffffffff824466a8 ffff88007c85e650
0000000000000003 0000000000000000 ffff88007c861f38 ffffffff82335e5d
ffff88007c862080 ffffffff8223d8c0 ffff88007c862080 ffffffff81c47760
Call Trace:
[<ffffffff81000312>] do_one_initcall+0x122/0x170
[<ffffffff82335e5d>] kernel_init_freeable+0x9b/0x1c8
[<ffffffff81c47760>] ? rest_init+0x140/0x140
[<ffffffff81c4776e>] kernel_init+0xe/0xf0
[<ffffffff81c6be9c>] ret_from_fork+0x7c/0xb0
[<ffffffff81c47760>] ? rest_init+0x140/0x140
...
v2: Typo fix in x86-32.
v3: CPU number dropped from show_regs_print_info() as
dump_stack_print_info() has been updated to print it. s390
specific implementation dropped as requested by s390 maintainers.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Chris Metcalf <cmetcalf@tilera.com> [tile bits]
Acked-by: Richard Kuo <rkuo@codeaurora.org> [hexagon bits]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Both dump_stack() and show_stack() are currently implemented by each
architecture. show_stack(NULL, NULL) dumps the backtrace for the
current task as does dump_stack(). On some archs, dump_stack() prints
extra information - pid, utsname and so on - in addition to the
backtrace while the two are identical on other archs.
The usages in arch-independent code of the two functions indicate
show_stack(NULL, NULL) should print out bare backtrace while
dump_stack() is used for debugging purposes when something went wrong,
so it does make sense to print additional information on the task which
triggered dump_stack().
There's no reason to require archs to implement two separate but mostly
identical functions. It leads to unnecessary subtle information.
This patch expands the dummy fallback dump_stack() implementation in
lib/dump_stack.c such that it prints out debug information (taken from
x86) and invokes show_stack(NULL, NULL) and drops arch-specific
dump_stack() implementations in all archs except blackfin. Blackfin's
dump_stack() does something wonky that I don't understand.
Debug information can be printed separately by calling
dump_stack_print_info() so that arch-specific dump_stack()
implementation can still emit the same debug information. This is used
in blackfin.
This patch brings the following behavior changes.
* On some archs, an extra level in backtrace for show_stack() could be
printed. This is because the top frame was determined in
dump_stack() on those archs while generic dump_stack() can't do that
reliably. It can be compensated by inlining dump_stack() but not
sure whether that'd be necessary.
* Most archs didn't use to print debug info on dump_stack(). They do
now.
An example WARN dump follows.
WARNING: at kernel/workqueue.c:4841 init_workqueues+0x35/0x505()
Hardware name: empty
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.9.0-rc1-work+ #9
0000000000000009 ffff88007c861e08 ffffffff81c614dc ffff88007c861e48
ffffffff8108f50f ffffffff82228240 0000000000000040 ffffffff8234a03c
0000000000000000 0000000000000000 0000000000000000 ffff88007c861e58
Call Trace:
[<ffffffff81c614dc>] dump_stack+0x19/0x1b
[<ffffffff8108f50f>] warn_slowpath_common+0x7f/0xc0
[<ffffffff8108f56a>] warn_slowpath_null+0x1a/0x20
[<ffffffff8234a071>] init_workqueues+0x35/0x505
...
v2: CPU number added to the generic debug info as requested by s390
folks and dropped the s390 specific dump_stack(). This loses %ksp
from the debug message which the maintainers think isn't important
enough to keep the s390-specific dump_stack() implementation.
dump_stack_print_info() is moved to kernel/printk.c from
lib/dump_stack.c. Because linkage is per objecct file,
dump_stack_print_info() living in the same lib file as generic
dump_stack() means that archs which implement custom dump_stack()
- at this point, only blackfin - can't use dump_stack_print_info()
as that will bring in the generic version of dump_stack() too. v1
The v1 patch broke build on blackfin due to this issue. The build
breakage was reported by Fengguang Wu.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> [s390 bits]
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Richard Kuo <rkuo@codeaurora.org> [hexagon bits]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull SMP/hotplug changes from Ingo Molnar:
"This is a pretty large, multi-arch series unifying and generalizing
the various disjunct pieces of idle routines that architectures have
historically copied from each other and have grown in random, wildly
inconsistent and sometimes buggy directions:
101 files changed, 455 insertions(+), 1328 deletions(-)
this went through a number of review and test iterations before it was
committed, it was tested on various architectures, was exposed to
linux-next for quite some time - nevertheless it might cause problems
on architectures that don't read the mailing lists and don't regularly
test linux-next.
This cat herding excercise was motivated by the -rt kernel, and was
brought to you by Thomas "the Whip" Gleixner."
* 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (40 commits)
idle: Remove GENERIC_IDLE_LOOP config switch
um: Use generic idle loop
ia64: Make sure interrupts enabled when we "safe_halt()"
sparc: Use generic idle loop
idle: Remove unused ARCH_HAS_DEFAULT_IDLE
bfin: Fix typo in arch_cpu_idle()
xtensa: Use generic idle loop
x86: Use generic idle loop
unicore: Use generic idle loop
tile: Use generic idle loop
tile: Enter idle with preemption disabled
sh: Use generic idle loop
score: Use generic idle loop
s390: Use generic idle loop
powerpc: Use generic idle loop
parisc: Use generic idle loop
openrisc: Use generic idle loop
mn10300: Use generic idle loop
mips: Use generic idle loop
microblaze: Use generic idle loop
...
The early console implementations are the same all over the place. Move
the print function to kernel/printk and get rid of the copies.
[akpm@linux-foundation.org: arch/mips/kernel/early_printk.c needs kernel.h for va_list]
[paul.gortmaker@windriver.com: sh4: make the bios early console support depend on EARLY_PRINTK]
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Russell King <linux@arm.linux.org.uk>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Richard Weinberger <richard@nod.at>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
