You can crash the kernel (with root/admin privileges) using kprobe tracer by running:
echo "p system_call_after_swapgs" > ./kprobe_events
echo 1 > ./events/kprobes/enable
The reason is that at the system_call_after_swapgs label, the
kernel stack is not set up. If optimized kprobes are enabled,
the user space stack is being used in this case (see optimized
kprobe template) and this might result in a crash.
There are several places like this over the entry code
(entry_$BIT). As it seems there's no any reasonable/maintainable
way to disable only those places where the stack is not ready, I
switched off the whole entry code from kprobe optimizing.
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: acme@redhat.com
Cc: fweisbec@gmail.com
Cc: ananth@in.ibm.com
Cc: davem@davemloft.net
Cc: a.p.zijlstra@chello.nl
Cc: eric.dumazet@gmail.com
Cc: 2nddept-manager@sdl.hitachi.co.jp
LKML-Reference: <1298298313-5980-3-git-send-email-jolsa@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Put x86 entry code into a separate link section: .entry.text.
Separating the entry text section seems to have performance
benefits - caused by more efficient instruction cache usage.
Running hackbench with perf stat --repeat showed that the change
compresses the icache footprint. The icache load miss rate went
down by about 15%:
before patch:
19417627 L1-icache-load-misses ( +- 0.147% )
after patch:
16490788 L1-icache-load-misses ( +- 0.180% )
The motivation of the patch was to fix a particular kprobes
bug that relates to the entry text section, the performance
advantage was discovered accidentally.
Whole perf output follows:
- results for current tip tree:
Performance counter stats for './hackbench/hackbench 10' (500 runs):
19417627 L1-icache-load-misses ( +- 0.147% )
2676914223 instructions # 0.497 IPC ( +- 0.079% )
5389516026 cycles ( +- 0.144% )
0.206267711 seconds time elapsed ( +- 0.138% )
- results for current tip tree with the patch applied:
Performance counter stats for './hackbench/hackbench 10' (500 runs):
16490788 L1-icache-load-misses ( +- 0.180% )
2717734941 instructions # 0.502 IPC ( +- 0.079% )
5414756975 cycles ( +- 0.148% )
0.206747566 seconds time elapsed ( +- 0.137% )
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: masami.hiramatsu.pt@hitachi.com
Cc: ananth@in.ibm.com
Cc: davem@davemloft.net
Cc: 2nddept-manager@sdl.hitachi.co.jp
LKML-Reference: <20110307181039.GB15197@jolsa.redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 's5p-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/kgene/linux-samsung:
ARM: S3C64XX: Update regulator names for debugfs compatiblity on SMDK6410
ARM: S3C64XX: Fix build with WM1190 disabled and WM1192 enabled on SMDK6410
ARM: S3C64XX: Reduce output of s3c64xx_dma_init1()
ARM: S3C64XX: Tone down SDHCI debugging
ARM: S3C64XX: Add clock for i2c1
ARM: S3C64XX: Staticise non-exported GPIO to interrupt functions
ARM: SAMSUNG: Include devs.h in dev-uart.c to prototype devices
ARM: S3C64XX: Fix keypad setup to configure correct number of rows
ARM: S3C2440: Fix usage gpio bank j pin definitions on GTA02
ARM: S5P64X0: Fix number of GPIO lines in Bank F
ARM: S3C2440: Select missing S3C_DEV_USB_HOST on GTA02
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1299119690-13991-5-git-send-email-ming.m.lin@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/vapier/blackfin:
Blackfin: iflush: update anomaly 05000491 workaround
Blackfin: outs[lwb]: make sure count is greater than 0
* 'sh-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6:
sh: Change __nosave_XXX symbols to long
sh: Flush executable pages in copy_user_highpage
sh: Ensure ST40-300 BogoMIPS value is consistent
sh: sh7750: Fix incompatible pointer type
sh: sh7750: move machtypes.h to include/generated
On Intel Nehalem and Westmere CPUs the generic perf LLC-* events count the
L2 caches, not the real L3 LLC - this was inconsistent with behavior on
other CPUs.
Fixing this requires the use of the special OFFCORE_RESPONSE
events which need a separate mask register.
This has been implemented by the previous patch, now use this infrastructure
to set correct events for the LLC-* on Nehalem and Westmere.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1299119690-13991-3-git-send-email-ming.m.lin@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Change logs against Andi's original version:
- Extends perf_event_attr:config to config{,1,2} (Peter Zijlstra)
- Fixed a major event scheduling issue. There cannot be a ref++ on an
event that has already done ref++ once and without calling
put_constraint() in between. (Stephane Eranian)
- Use thread_cpumask for percore allocation. (Lin Ming)
- Use MSR names in the extra reg lists. (Lin Ming)
- Remove redundant "c = NULL" in intel_percore_constraints
- Fix comment of perf_event_attr::config1
Intel Nehalem/Westmere have a special OFFCORE_RESPONSE event
that can be used to monitor any offcore accesses from a core.
This is a very useful event for various tunings, and it's
also needed to implement the generic LLC-* events correctly.
Unfortunately this event requires programming a mask in a separate
register. And worse this separate register is per core, not per
CPU thread.
This patch:
- Teaches perf_events that OFFCORE_RESPONSE needs extra parameters.
The extra parameters are passed by user space in the
perf_event_attr::config1 field.
- Adds support to the Intel perf_event core to schedule per
core resources. This adds fairly generic infrastructure that
can be also used for other per core resources.
The basic code has is patterned after the similar AMD northbridge
constraints code.
Thanks to Stephane Eranian who pointed out some problems
in the original version and suggested improvements.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1299119690-13991-2-git-send-email-ming.m.lin@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This patch updates PEBS event constraints for Intel Atom, Nehalem, Westmere.
This patch also reorganizes the PEBS format/constraint detection code. It is
now based on processor model and not PEBS format. Two processors may use the
same PEBS format without have the same list of PEBS events.
In this second version, we simplified the initialization of the PEBS
constraints by leveraging the existing switch() statement in perf_event_intel.c.
We also renamed the constraint tables to be more consistent with regular
constraints.
In this 3rd version, we drop BR_INST_RETIRED.MISPRED from Intel Atom as it does
not seem to work. Use MISPREDICTED_BRANCH_RETIRED instead. Also add FP_ASSIST.*
o both Intel Nehalem and Westmere. I misssed those in the earlier patches.
Events were tested using libpfm4 perf_examples.
Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <4d6e6b02.815bdf0a.637b.07a7@mx.google.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The debugfs support added to the regulator API (which has been merged
in during this merge window) creates directories for regulators named
after the display names for the regulators so replace / as a separator
for multiple supplies with + in the SMDK6410 machine.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
Avoid relying on implicit inclusion of machine.h
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
Reduce the logging output of s3c64xx_dma_init1() as it is not useful
for normal bootup (and we get an overall indication of the registration
of the PL180 DMA block).
This removes the following output from the log:
s3c64xx_dma_init1: registering DMA 0 (e0808100)
s3c64xx_dma_init1: registering DMA 1 (e0808120)
s3c64xx_dma_init1: registering DMA 2 (e0808140)
s3c64xx_dma_init1: registering DMA 3 (e0808160)
s3c64xx_dma_init1: registering DMA 4 (e0808180)
s3c64xx_dma_init1: registering DMA 5 (e08081a0)
s3c64xx_dma_init1: registering DMA 6 (e08081c0)
s3c64xx_dma_init1: registering DMA 7 (e08081e0)
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
The MMC core calls s3c6400_setup_sdhcp_cfg_card() very frequently, causing
the log message in there at KERN_INFO to be displayed a lot which is slow
and overly chatty. Convert the message into a pr_debug() to tone this down.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
The clock for i2c1 has been missing for a while, add it to the list of
clocks for the system and ensure it is initialised at startup.
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
No need to put these in the global namespace and sparse gets upset.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
Ensures that the declaration agrees with the definition and makes sparse
happy.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
The call to s3c_gpio_cfgrange_nopull() takes a size and base
but this looks like it is trying to do base and end. This means
it is configuring too many GPIOs and on the case of the Cragganmore
means we're seeing an overflow of the ROW pins causing problems
with the keyboard driver.
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
The gta02 header file still uses the old S3C2410_GPJx defines instead of the
S3C2410_GPJ(x) macro. Since the S3C2410_GPJx defines have already been removed
this causes the following build failure:
sound/soc/samsung/neo1973_wm8753.c: In function 'lm4853_set_spk':
sound/soc/samsung/neo1973_wm8753.c:259: error: 'S3C2440_GPJ2' undeclared (first use in this function)
sound/soc/samsung/neo1973_wm8753.c:259: error: (Each undeclared identifier is reported only once
sound/soc/samsung/neo1973_wm8753.c:259: error: for each function it appears in.)
sound/soc/samsung/neo1973_wm8753.c: In function 'lm4853_get_spk':
sound/soc/samsung/neo1973_wm8753.c:267: error: 'S3C2440_GPJ2' undeclared (first use in this function)
sound/soc/samsung/neo1973_wm8753.c: In function 'lm4853_event':
sound/soc/samsung/neo1973_wm8753.c:276: error: 'S3C2440_GPJ1' undeclared (first use in this function)
sound/soc/samsung/neo1973_wm8753.c: At top level:
sound/soc/samsung/neo1973_wm8753.c:439: error: 'S3C2440_GPJ2' undeclared here (not in a function)
sound/soc/samsung/neo1973_wm8753.c:440: error: 'S3C2440_GPJ1' undeclared here (not in a function)
This patches fixes the issue by doing a s,S3C2410_GPJ([\d]+),S3C2410_GPJ(\1),g
on the file.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
This patch modifies the number of total GPIO lines for Bank F
for Samsung S5P6440 and S5P6450 SoCs from 2 to 16.
This is necessary as the GPIO lines from 0 to 13 are reserved
and only lines 14 and 15 are used. As during initialization,
the line number starts at 0, putting 2 does not solve the
intended purpose.
Signed-off-by: Banajit Goswami <banajit.g@samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
The gta02 mach file references the ohci device.
So we need to select S3C_DEV_USB_HOST to have the device available.
This fixes the following linker errors:
arch/arm/mach-s3c2440/built-in.o: In function 'gta02_machine_init':
mach-gta02.c:(.init.text+0x370): undefined reference to 's3c_ohci_set_platdata'
arch/arm/mach-s3c2440/built-in.o:(.init.data+0xac): undefined reference to 's3c_device_ohci'
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
Some devices will use the outs* funcs with a length of zero, so make sure
we do not write any data in that case.
Reported-by: Gilbert Inho <gneny@edevice.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
omap4 interrupt disable bits is different. On rx kfifo full, the mbox rx
interrupts wasn't getting disabled, and this is causing the rcm stress tests
to hang.
Signed-off-by: Hari Kanigeri <h-kanigeri2@ti.com>
Signed-off-by: Armando Uribe <x0095078@ti.com>
Signed-off-by: Fernando Guzman Lugo <fernando.lugo@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
* 'devicetree/merge' of git://git.secretlab.ca/git/linux-2.6:
of/promtree: allow DT device matching by fixing 'name' brokenness (v5)
x86: OLPC: have prom_early_alloc BUG rather than return NULL
of/flattree: Drop an uninteresting message to pr_debug level
of: Add missing of_address.h to xilinx ehci driver
* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/davej/cpufreq:
[CPUFREQ] p4-clockmod: print EST-capable warning message only once
[CPUFREQ] fix BUG on cpufreq policy init failure
[CPUFREQ] Fix another notifier leak in powernow-k8.
[CPUFREQ] Missing "unregister_cpu_notifier" in powernow-k8.c
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
powerpc: Fix call to flush_ptrace_hw_breakpoint()
powerpc/kexec: Restore ppc_md.machine_kexec
powerpc/mm: Make hpte_need_flush() safe for preemption
..similar to what sparc's prom_early_alloc does.
Signed-off-by: Andres Salomon <dilinger@queued.net>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
The irq descriptors are initialized IRQ_DISABLED in the generic
code. No need to fiddle with them.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Matt Turner <mattst88@gmail.com>
