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>
cyc_to_sched_clock() is called by sched_clock() and cyc_to_ns()
is called by cyc_to_sched_clock(). I suspect that some compilers
inline both of these functions into sched_clock() and so we've
been getting away without having a notrace marking. It seems that
my compiler isn't inlining cyc_to_sched_clock() though, so I'm
hitting a recursion bug when I enable the function graph tracer,
causing my system to crash. Marking these functions notrace fixes
it. Technically cyc_to_ns() doesn't need the notrace because it's
already marked inline, but let's just add it so that if we ever
remove inline from that function it doesn't blow up.
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Events may be created with attr->disabled == 1 and attr->enable_on_exec
== 1, which confuses the group validation code because events with the
PERF_EVENT_STATE_OFF are not considered candidates for scheduling, which
may lead to failure at group scheduling time.
This patch fixes the validation check for ARM, so that events in the
OFF state are still considered when enable_on_exec is true.
Cc: stable@vger.kernel.org
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Cc: Jiri Olsa <jolsa@redhat.com>
Reported-by: Sudeep KarkadaNagesha <Sudeep.KarkadaNagesha@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
tcm_init() call iotable_init() and it use early_alloc variants which
do memblock allocation. Directly using memblock allocation after
initializing bootmem should not permitted, because bootmem can't know
where are additinally reserved.
So move tcm_init() to a safe place before initalizing bootmem.
(On the U300)
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
CONFIG_LPAE doesn't exist: the correct option is CONFIG_ARM_LPAE, so fix
up the two typos under arch/arm/.
The fix to head.S is slightly scary, but this is just for setting up
an early io-mapping for the serial port when running on a big-endian,
LPAE system. Since these systems don't exist in the wild (at least, I
have no access to one outside of kvmtool, which doesn't provide a serial
port suitable for earlyprintk), then we can revisit the code later if it
causes any problems.
Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Add unwind annotations to the ftrace assembly code so that the function
tracer's stacktracing options (func_stack_trace, etc.) work when
CONFIG_ARM_UNWIND is enabled.
Signed-off-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Commit 70264367a2 ("ARM: 7653/2: do not scale loops_per_jiffy when
using a constant delay clock") fixed a problem with our timer-based
delay loop, where loops_per_jiffy is scaled by cpufreq yet used directly
by the timer delay ops.
This patch fixes the problem in a more elegant way by keeping a private
ticks_per_jiffy field in the delay ops, independent of loops_per_jiffy
and therefore not subject to scaling. The loop-based delay continues to
use loops_per_jiffy directly, as it should.
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
On Cortex-A15 (r0p0..r3p2) the TLBI/DSB are not adequately shooting down
all use of the old entries. This patch implements the erratum workaround
which consists of:
1. Dummy TLBIMVAIS and DSB on the CPU doing the TLBI operation.
2. Send IPI to the CPUs that are running the same mm (and ASID) as the
one being invalidated (or all the online CPUs for global pages).
3. CPU receiving the IPI executes a DMB and CLREX (part of the exception
return code already).
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
CPU debug features like hardware break, watchpoints can be used only
when the debug mode is enabled and available. Unfortunately on OMAP4
based devices, after a CPU power cycle, the debug feature gets disabled
which leads to a flood of messages coming from reset_ctrl_regs() which
gets called on every CPU_PM_EXIT with CPUidle enabled.
So make use of warn_once() so that system is usable.
Thanks to Will for pointers and Lokesh for the analysis of the issue.
Tested-by: Lokesh Vutla <lokeshvutla@ti.com>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The ISAR0 register indicates support for the SDIV and UDIV
instructions in both the Thumb and ARM instruction set. Read the
register to detect the supported instructions and update the
elf_hwcap mask as appropriate. This is better than adding more
and more cpuid checks in proc-v7.S for each new cpu variant that
supports these instructions.
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: Stepan Moskovchenko <stepanm@codeaurora.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Don't advertise support for the SDIV/UDIV thumb instructions if
the kernel is not compiled with support for thumb userspace. This
is in line with how we remove the THUMB hwcap in these
configurations.
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: Stepan Moskovchenko <stepanm@codeaurora.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
With recent arm broadcast time clean-up from Mark Rutland, the dummy
broadcast device is always registered with timer subsystem. And since
the rating of the dummy clock event is very high, it may be preferred
over a real clock event.
This is a change in behavior from past and not an intended one. So
reduce the rating of the dummy clock-event so that real clock-event
device is selected when available.
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
WARNING: vmlinux.o(.text+0xfb80): Section mismatch in reference
from the function armpmu_register() to the function
.init.text:armpmu_init()
The function armpmu_register() references
the function __init armpmu_init().
This is often because armpmu_register lacks a __init
annotation or the annotation of armpmu_init is wrong.
Just drop the __init marking on armpmu_init() because
armpmu_register() no longer has an __init marking.
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Commit 9dcbf46655 ("ARM: perf: simplify __hw_perf_event_init err
handling") tidied up the error handling code for perf event
initialisation on ARM, but a copy-and-paste error left a dangling
semicolon at the end of an if statement.
This patch removes the broken semicolon, restoring the old group
validation semantics.
Cc: Mark Rutland <mark.rutland@arm.com>
Acked-by: Dirk Behme <dirk.behme@gmail.com>
Signed-off-by: Chen Gang <gang.chen@asianux.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
We must mask out the CPU_TASKS_FROZEN bit so that reset_ctrl_regs is
also called on a secondary CPU during s2ram resume, where only the boot
CPU will receive the PM_EXIT notification.
Signed-off-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
