This patch fixes the preempt leak in the cpuidle path invoked from
cpu-hotplug. The fix is suggested by Russell King and is based
on x86 idea of calling init_idle() on the idle task when it's
re-used which also resets the preempt count amongst other things
dump:
BUG: scheduling while atomic: swapper/0/0x00000002
Modules linked in:
Backtrace:
[<c0024f90>] (dump_backtrace+0x0/0x110) from [<c0173bc4>] (dump_stack+0x18/0x1c)
r7:c02149e4 r6:c033df00 r5:c7836000 r4:00000000
[<c0173bac>] (dump_stack+0x0/0x1c) from [<c003b4f0>] (__schedule_bug+0x60/0x70)
[<c003b490>] (__schedule_bug+0x0/0x70) from [<c0174214>] (schedule+0x98/0x7b8)
r5:c7836000 r4:c7836000
[<c017417c>] (schedule+0x0/0x7b8) from [<c00228c4>] (cpu_idle+0xb4/0xd4)
# [<c0022810>] (cpu_idle+0x0/0xd4) from [<c0171dd8>] (secondary_start_kernel+0xe0/0xf0)
r5:c7836000 r4:c0205f40
[<c0171cf8>] (secondary_start_kernel+0x0/0xf0) from [<c002d57c>] (prm_rmw_mod_reg_bits+0x88/0xa4)
r7:c02149e4 r6:00000001 r5:00000001 r4:c7836000
Backtrace aborted due to bad frame pointer <c7837fbc>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
With CONFIG_KPROBES enabled two section are getting created which
leads to below build break.
LOG:
AS arch/arm/kernel/entry-armv.o
arch/arm/kernel/entry-armv.S: Assembler messages:
arch/arm/kernel/entry-armv.S:431: Error: symbol ret_from_exception is in a different section
arch/arm/kernel/entry-armv.S:490: Error: symbol ret_from_exception is in a different section
arch/arm/kernel/entry-armv.S:491: Error: symbol __und_usr_unknown is in a different section
This was introduced by commit 4260415f6a
Reported-by: Anand Gadiyar <gadiyar@ti.com>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This patch adds support for PCI domains on ARM platforms.
Also, protect asm/mach/pci.h from multiple inclustions, otherwise
build fails because of pci_domain_nr() and pci_proc_domain()
redefinitions.
Signed-off-by: Anton Vorontsov <avorontsov@mvista.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
/tmp/ccJ3ssZW.s: Assembler messages:
/tmp/ccJ3ssZW.s:1952: Error: can't resolve `.text' {.text section} - `.LFB1077'
This is caused because:
.section .data
.section .text
.section .text
.previous
does not return us to the .text section, but the .data section; this
makes use of .previous dangerous if the ordering of previous sections
is not known.
Fix up the other users of .previous; .pushsection and .popsection are
a safer pairing to use than .section and .previous.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
We have our own private implementation for ISA-like DMA which has been
missing exposure via the /proc/dma interface. Add support for this.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
From: Imre Deak <imre.deak@nokia.com>
Signal handlers can use floating point, so prevent them to corrupt
the main thread's VFP context. So far there were two signal stack
frame formats defined based on the VFP implementation, but the user
struct used for ptrace covers all posibilities, so use it for the
signal stack too.
Introduce also a new user struct for VFP exception registers. In
this too fields not relevant to the current VFP architecture are
ignored.
Support to save / restore the exception registers was added by
Will Deacon.
Signed-off-by: Imre Deak <imre.deak@nokia.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.
percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.
http://userweb.kernel.org/~tj/misc/slabh-sweep.py
The script does the followings.
* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.
* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.
* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.
The conversion was done in the following steps.
1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.
2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.
3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.
4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.
5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.
6. percpu.h was updated not to include slab.h.
7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).
* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig
8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.
Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
Current implementation of jprobes allocates empty pt_regs from the
stack which is then passed to kprobe_handler() and eventually to
singlestep(). Now when instruction being simulated is STMFD (like
in normal function prologues without CONFIG_FRAME_POINTER), stores
using SP actually write over top of the fabricated pt_regs
structure.
This can be reproduced for example by using LKDTM module:
# modprobe lkdtm
# mount -t debugfs none /sys/kernel/debug
# echo PANIC > /sys/kernel/debug/provoke-crash/INT_HW_IRQ_EN
after this, it fails with corrupted registers (before the requested crash would occur):
lkdtm: Crash point INT_HW_IRQ_EN of type PANIC hit, trigger in 9 rounds
lkdtm: Crash point INT_HW_IRQ_EN of type PANIC hit, trigger in 8 rounds
Internal error: Oops - undefined instruction: 0 [#1]
last sysfs file: /sys/devices/platform/serial8250.0/sleep_timeout
Modules linked in: lkdtm
CPU: 0 Not tainted (2.6.34-rc2 #69)
PC is at irq_desc+0x1638/0xeeb0
LR is at 0x25
pc : [<c050b428>] lr : [<00000025>] psr: c80a0013
sp : ce94bd60 ip : c050b3e8 fp : a0000013
r10: c0aa453c r9 : cf5d4000 r8 : ce9a1822
r7 : c050b424 r6 : 00000025 r5 : c039d8f8 r4 : c050b3e8
r3 : 00000001 r2 : cf4d0440 r1 : c039d8f8 r0 : 00000020
Flags: NZcv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user
Control: 10c5387d Table: 8e804019 DAC: 00000015
Process sh (pid: 496, stack limit = 0xce94a2e8)
Stack: (0xce94bd60 to 0xce94c000)
[...]
Code: 000002cd 00000000 00000000 00000001 (dead4ead)
---[ end trace 2b46d5f2b682f370 ]---
Kernel panic - not syncing: Fatal exception in interrupt
This patch allocates enough space (2 * sizeof(struct pt_regs)) from
the stack to prevent such corruption.
Signed-off-by: Mika Westerberg <ext-mika.1.westerberg@nokia.com>
Acked-by: Nicolas Pitre <nico@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Convert arm to use GENERIC_TIME via the arch_getoffset() infrastructure,
reducing the amount of arch specific code we need to maintain.
The arm architecture is the last arch that need to be converted.
Signed-off-by: John Stultz <johnstul@us.ibm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
ARMv5T and earlier require that a ldm {}^ instruction is not followed
by an instruction that accesses banked registers. This patch restores
the nop that was lost in commit b86040a59f.
Signed-off-by: Anders Grafström <grfstrm@users.sourceforge.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
To support SMP platforms, KGDB requires the architecture backend to
implement the kgdb_roundup_cpus function.
This patch, taken against 2.6.33, implements the function for ARM based
on the MIPS port.
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Jean-Michel Hautbois <jhautbois@gmail.com>
Cc: KGDB Mailing List <kgdb-bugreport@lists.sourceforge.net>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The page table and secondary data which we're asking the secondary CPU
to make use of has to hit RAM to ensure that the secondary CPU can see
it since it may not be taking part in coherency or cache searches at
this point.
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
perf: Provide generic perf_sample_data initialization
MAINTAINERS: Add Arnaldo as tools/perf/ co-maintainer
perf trace: Don't use pager if scripting
perf trace/scripting: Remove extraneous header read
perf, ARM: Modify kuser rmb() call to compile for Thumb-2
x86/stacktrace: Don't dereference bad frame pointers
perf archive: Don't try to collect files without a build-id
perf_events, x86: Fixup fixed counter constraints
perf, x86: Restrict the ANY flag
perf, x86: rename macro in ARCH_PERFMON_EVENTSEL_ENABLE
perf, x86: add some IBS macros to perf_event.h
perf, x86: make IBS macros available in perf_event.h
hw-breakpoints: Remove stub unthrottle callback
x86/hw-breakpoints: Remove the name field
perf: Remove pointless breakpoint union
perf lock: Drop the buffers multiplexing dependency
perf lock: Fix and add misc documentally things
percpu: Add __percpu sparse annotations to hw_breakpoint
The event selection mask for ARMv7 cores [ARMV7_EVTSEL_MASK]
is incorrectly set to 0x7f. This means that the top bit of an
event ID is ignored, so counting branch misses (id=0x10) and
ISBs (id=0x90) give the same results.
This patch sets the event selection mask to the correct value
of 0xff.
Signed-off-by: Jean Pihet <jpihet@mvista.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
If IRQ balancing is used on a multicore ARM system, PMU interrupt
lines may be relocated onto CPUs other than the one causing the
counter overflow. This can result in misattribution of events to
the wrong core and, in the case that the CPU handling the interrupt
has not experience counter overflow, the interrupt can be disabled
because the handler returns IRQ_NONE.
This patch adds the IRQF_NOBALANCING flag to the request_irq call
in perf_events.c.
Acked-by: Jamie Iles <jamie.iles@picochip.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm: (370 commits)
ARM: S3C2443: Add set_rate and round_rate calls for armdiv clock
ARM: S3C2443: Remove #if 0 for clk_mpll
ARM: S3C2443: Update notes on MPLLREF clock
ARM: S3C2443: Further clksrc-clk conversions
ARM: S3C2443: Change to using plat-samsung clksrc-clk implementation
USB: Fix s3c-hsotg build following Samsung platform header moves
ARM: S3C64XX: Reintroduce unconditional build of audio device
ARM: 5961/1: ux500: fix CLKRST addresses
ARM: 5977/1: arm: Enable backtrace printing on oops when PC is corrupted
ASoC: Fix S3C64xx IIS driver for Samsung header reorg
ARM: S3C2440: Fix plat-s3c24xx move of s3c2440/s3c2442 support
[ARM] pxa: fix typo in mxm8x10.h
[ARM] pxa/raumfeld: set GPIO drive bits for LED pins
[ARM] pxa/zeus: Add support for mcp2515 CAN bus
[ARM] pxa/zeus: Add support for onboard max6369 watchdog
[ARM] pxa/zeus: Add Eurotech as the manufacturer
[ARM] pxa/zeus: Correct the USB host initialisation flags
[ARM] pxa/zeus: Allow usage of 8250-compatible UART in uncompress
[ARM] pxa: refactor uncompress.h for non-PXA uarts
[ARM] mmp2: fix incorrect calling of chip->mask_ack() for 2nd level cascaded IRQs
...
Use the generic ptrace_resume code for PTRACE_SYSCALL, PTRACE_CONT,
PTRACE_KILL and PTRACE_SINGLESTEP. This implies defining
arch_has_single_step in <asm/ptrace.h> and implementing the
user_enable_single_step and user_disable_single_step functions, which also
causes the breakpoint information to be cleared on fork, which could be
considered a bug fix.
Also the TIF_SYSCALL_TRACE thread flag is now cleared on PTRACE_KILL which
it previously wasn't and the single stepping disable only happens if the
tracee process isn't a zombie yet, which is consistent with all
architectures using the modern ptrace code.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Roland McGrath <roland@redhat.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add a generic implementation of the ipc demultiplexer syscall. Except for
s390 and sparc64 all implementations of the sys_ipc are nearly identical.
There are slight differences in the types of the parameters, where mips
and powerpc as the only 64-bit architectures with sys_ipc use unsigned
long for the "third" argument as it gets casted to a pointer later, while
it traditionally is an "int" like most other paramters. frv goes even
further and uses unsigned long for all parameters execept for "ptr" which
is a pointer type everywhere. The change from int to unsigned long for
"third" and back to "int" for the others on frv should be fine due to the
in-register calling conventions for syscalls (we already had a similar
issue with the generic sys_ptrace), but I'd prefer to have the arch
maintainers looks over this in details.
Except for that h8300, m68k and m68knommu lack an impplementation of the
semtimedop sub call which this patch adds, and various architectures have
gets used - at least on i386 it seems superflous as the compat code on
x86-64 and ia64 doesn't even bother to implement it.
[akpm@linux-foundation.org: add sys_ipc to sys_ni.c]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Reviewed-by: H. Peter Anvin <hpa@zytor.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: James Morris <jmorris@namei.org>
Cc: Andreas Schwab <schwab@linux-m68k.org>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: David Howells <dhowells@redhat.com>
Acked-by: Kyle McMartin <kyle@mcmartin.ca>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add a generic implementation of the old mmap() syscall, which expects its
argument in a memory block and switch all architectures over to use it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Reviewed-by: H. Peter Anvin <hpa@zytor.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: James Morris <jmorris@namei.org>
Cc: Andreas Schwab <schwab@linux-m68k.org>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Greg Ungerer <gerg@uclinux.org>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add a generic implementation of the old select() syscall, which expects
its argument in a memory block and switch all architectures over to use
it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Reviewed-by: H. Peter Anvin <hpa@zytor.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: James Morris <jmorris@namei.org>
Acked-by: Andreas Schwab <schwab@linux-m68k.org>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Greg Ungerer <gerg@uclinux.org>
Acked-by: David Howells <dhowells@redhat.com>
Cc: Andreas Schwab <schwab@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This makes it easier to extend perf_sample_data and fixes a bug on arm
and sparc, which failed to set ->raw to NULL, which can cause crashes
when combined with PERF_SAMPLE_RAW.
It also optimizes PowerPC and tracepoint, because the struct
initialization is forced to zero out the whole structure.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Jean Pihet <jpihet@mvista.com>
Reviewed-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: David S. Miller <davem@davemloft.net>
Cc: Jamie Iles <jamie.iles@picochip.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: stable@kernel.org
LKML-Reference: <20100304140100.315416040@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
If PC points outside kernel text, start printing the backtrace at LR
instead.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Now that we return the new resource start position, there is no
need to update "struct resource" inside the align function.
Therefore, mark the struct resource as const.
Cc: Bjorn Helgaas <bjorn.helgaas@hp.com>
Cc: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
As suggested by Linus, align functions should return the start
of a resource, not void. An update of "res->start" is no longer
necessary.
Cc: Bjorn Helgaas <bjorn.helgaas@hp.com>
Cc: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
The 'outer_cache' variable is needed by the outer_inv_range(),
outer_clean_range() and outer_flush_range() functions, which are
declared as inline in asm/cacheflush.h. Otherwise drivers built
as a loadable module, which access these functions, will have
an undefined symbol.
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
If we're only reading the VFP context via the ptrace call, there's
no need to invalidate the hardware context - we only need to do that
on PTRACE_SETVFPREGS. This allows more efficient monitoring of a
traced task.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The generic ptrace_request() handles these for us, so there's no
need to duplicate them in arch code.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Recognize 0xf7f0 0xa000 as a 32-bit breakpoint instruction for
Thumb-2.
Signed-off-by: Daniel Jacobowitz <dan@codesourcery.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
drivers/of/fdt expects a cmd_line symbol, while arm uses command_line.
Change to the former, so that we can eventually share with the fdt
code.
Signed-off-by: Jeremy Kerr <jeremy.kerr@canonical.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Kernel debuggers want to be informed of die() events, so that they
can take some action to allow the problem to be inspected. Provide
the hook in a similar manner to x86.
Note that we currently don't implement the individual trap hooks.
Acked-by: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The ARM setup code includes its own parser for early params, there's
also one in the generic init code.
This patch removes __early_init (and related code) from
arch/arm/kernel/setup.c, and changes users to the generic early_init
macro instead.
The generic macro takes a char * argument, rather than char **, so we
need to update the parser functions a little.
Signed-off-by: Jeremy Kerr <jeremy.kerr@canonical.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Always creating this directory avoids other users having to jump
through silly hoops when they want to share this directory.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
All RTC drivers have been converted to rtclib, so the old code
providing the set_rtc function pointer, save_time_delta() and
restore_time_delta() functions is obsolete. Remove it.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Otherwise more complicated uart configuration won't be possible.
We can use r1 for tmp register for both head.S and debug.S.
NOTE: This patch depends on another patch to add the the tmp register
into all debug-macro.S files. That can be done with:
$ sed -i -e "s/addruart,rx|addruart, rx/addruart, rx, tmp/"
arch/arm/*/include/*/debug-macro.S
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Adds the Performance Events support for ARMv7 processor, using
the PMNC unit in HW.
Supports the following:
- Cortex-A8 and Cortex-A9 processors,
- dynamic detection of the number of available counters,
based on the PMCR value,
- runtime detection of the CPU arch (v6 or v7)
and model (Cortex-A8 or Cortex-A9)
Tested on OMAP3 (Cortex-A8) only.
Signed-off-by: Jean Pihet <jpihet@mvista.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This patch implements support for ARMv6 performance counters in the
Linux performance events subsystem. ARMv6 architectures that have the
performance counters should enable HW_PERF_EVENTS to get hardware
performance events support in addition to the software events.
Note: only ARM Ltd ARM cores are supported.
This implementation also provides an ARM PMU abstraction layer to allow
ARMv7 and others to be supported in the future by adding new a
'struct arm_pmu'.
Cc: Jean Pihet <jpihet@mvista.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Jamie Iles <jamie.iles@picochip.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
To add support for perf events and to allow the hardware counters to be
shared with oprofile, we need a way to reserve access to the pmu
(performance monitor unit). Platforms with PMU interrupts should
register the interrupts in arch/arm/kernel/pmu.c
Signed-off-by: Jamie Iles <jamie.iles@picochip.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Without this patch arch/arm/compressed/head.S defaults to generic
DCC code that does not work for v7.
For more information on the v7 DCC, see Cortex-A8 TRM
"12.11.1 Debug communications channel".
To use it with post 2.6.33-rc1 or later, you need to have:
CONFIG_DEBUG_LL=y
ONFIG_DEBUG_ICEDCC=y
CONFIG_EARLY_PRINTK=y
Earlier kernels need commit 93fd03a8c6
backported.
Tested on omap3430.
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This reverts commit 14f0aa3593.
That commit was needed earlier because system call restarting for
OABI (compat) required an executable stack and thus had problems
with NX. Since ab72b00734 ("ARM: Fix signal restart issues
with NX and OABI compat") has reworked the code to not require an
executable stack anymore, we can re-enable NX support for kernels
with OABI (compat) support.
Signed-off-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The __kuser_cmpxchg code uses an ARMv6 dmb instruction, rather than
one based upon the architecture being built for. Switch to using
the macro provided for this purpose, which also eliminates the
need for an ifdef.
Acked-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Fix the following warning, which appears when the register dump for a
faulting process is printed in a kernel with SMP, DEBUG_PREEMPT, and
DEBUG_USER (with user_debug=31) enabled:
BUG: using smp_processor_id() in preemptible [00000000] code: init/1
caller is __show_regs+0x18/0x234
Backtrace:
[<c0159e5c>] (dump_backtrace+0x0/0x114) from [<c01faf30>] (dump_stack+0x18/0x1c)
r6:c781a000 r5:c0157544 r4:00000001 r3:00000000
[<c01faf18>] (dump_stack+0x0/0x1c) from [<c01e5230>] (debug_smp_processor_id+0xc4/0xf8)
[<c01e516c>] (debug_smp_processor_id+0x0/0xf8) from [<c0157544>] (__show_regs+0x18/0x234)
r6:c781bfb0 r5:00000000 r4:c781bfb0 r3:00000000
[<c015752c>] (__show_regs+0x0/0x234) from [<c01577a0>] (show_regs+0x40/0x50)
[<c0157760>] (show_regs+0x0/0x50) from [<c015c968>] (__do_user_fault+0x5c/0xa4)
r4:c781c000 r3:00000000
[<c015c90c>] (__do_user_fault+0x0/0xa4) from [<c015cbe0>] (do_page_fault+0x1b4/0x1e4)
r7:00000000 r6:00010000 r5:c781bfb0 r4:c781c000
[<c015ca2c>] (do_page_fault+0x0/0x1e4) from [<c01554c8>] (do_DataAbort+0x3c/0xa0)
[<c015548c>] (do_DataAbort+0x0/0xa0) from [<c01560c4>] (ret_from_exception+0x0/0x10)
Signed-off-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This avoids races in the VFP code where the dead thread may have
state on another CPU. By moving this code to exit_thread(), we
will be running as the thread, and therefore be running on the
current CPU.
This means that we can ensure that the only local state is accessed
in the thread notifiers.
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* 'module' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus:
modpost: fix segfault with short symbol names
module: handle ppc64 relocating kcrctabs when CONFIG_RELOCATABLE=y
Kbuild: clear marker out of modpost
module: make MODULE_SYMBOL_PREFIX into a CONFIG option
ARM: unexport symbols used to implement floating point emulation
ARM: use unified discard definition in linker script
x86: don't export inline function
sparc64: don't export static inline pci_ functions
The Kconfigs for in-tree floating point emulation do not allow building
as modules. That leaves the Acorn FPEmulator module. I found two public
releases of this as a binary module for 2.1 and 2.2 kernels, optimized
for ARMV4.[1] If there is a resurgence of interest in this, the symbols
can always be re-exported.
This allows the EXPORT_SYMBOL_ALIAS() hack to be removed. The ulterior
motive here is that EXPORT_SYMBOL_ALIAS() makes it harder to sort the
resulting kernel symbol tables. Sorted symbol tables will allow faster
symbol resolution during module loading.
Note that fp_send_sigs() and fp_printk() are simply aliases for existing
exports and add no obvious value. Similarly fp_enter could easily be
renamed to kern_fp_enter at the point of definition. Therefore removing
EXPORT_SYMBOL_ALIAS will not serve as a material obstacle to re-adding
the exports should they be desired in future.
Build tested only.
[1] http://ftp.arm.linux.org.uk/pub/linux/arm/fpemulator/
Signed-off-by: Alan Jenkins <alan-jenkins@tuffmail.co.uk>
CC: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Commit 023bf6f "linker script: unify usage of discard definition"
changed the linker scripts for all architectures except for ARM.
I can find no discussion about this ommision, so here are the changes
for ARM.
These changes are exactly parallel to the ia64 case.
"ia64 is notable because it first throws away some ia64 specific
subsections and then include the rest of the sections into the final
image, so those sections must be discarded before the inclusion."
Not boot-tested. In build testing, the modified linker script generated
an identical vmlinux file.
[I would like to be able to rely on this unified discard definition.
I want to sort the kernel symbol tables to allow faster symbol
resolution during module loading. The simplest way appears to be
to generate sorted versions from vmlinux.o, link them in to vmlinux,
_and discard the original unsorted tables_.
This work is driven by my x86 netbook, but it is implemented at a
generic level. It is possible it will benefit some ARM systems also.]
Signed-off-by: Alan Jenkins <alan-jenkins@tuffmail.co.uk>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by-without-testing: Tejun Heo <tj@kernel.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Convert locks which cannot be sleeping locks in preempt-rt to
raw_spinlocks.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Ingo Molnar <mingo@elte.hu>
New helper - sys_mmap_pgoff(); switch syscalls to using it.
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Since this IRQ descriptor doesn't have an action registered, it is
allowed for probing via probe_irq_on/off() and it will be disabled by
the latter function. This patch sets the IRQ_NOPROBE status bit for the
local timer descriptor.
Signed-off-by: Varun Swara <Varun.Swara@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
This patch allows an earlyprintk console if CONFIG_DEBUG_LL is enabled,
using the printch asm function.
The patch is based on the original work by Sascha Hauer.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Pavel Machek <pavel@ucw.cz>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6: (1815 commits)
mac80211: fix reorder buffer release
iwmc3200wifi: Enable wimax core through module parameter
iwmc3200wifi: Add wifi-wimax coexistence mode as a module parameter
iwmc3200wifi: Coex table command does not expect a response
iwmc3200wifi: Update wiwi priority table
iwlwifi: driver version track kernel version
iwlwifi: indicate uCode type when fail dump error/event log
iwl3945: remove duplicated event logging code
b43: fix two warnings
ipw2100: fix rebooting hang with driver loaded
cfg80211: indent regulatory messages with spaces
iwmc3200wifi: fix NULL pointer dereference in pmkid update
mac80211: Fix TX status reporting for injected data frames
ath9k: enable 2GHz band only if the device supports it
airo: Fix integer overflow warning
rt2x00: Fix padding bug on L2PAD devices.
WE: Fix set events not propagated
b43legacy: avoid PPC fault during resume
b43: avoid PPC fault during resume
tcp: fix a timewait refcnt race
...
Fix up conflicts due to sysctl cleanups (dead sysctl_check code and
CTL_UNNUMBERED removed) in
kernel/sysctl_check.c
net/ipv4/sysctl_net_ipv4.c
net/ipv6/addrconf.c
net/sctp/sysctl.c
* git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/sysctl-2.6: (43 commits)
security/tomoyo: Remove now unnecessary handling of security_sysctl.
security/tomoyo: Add a special case to handle accesses through the internal proc mount.
sysctl: Drop & in front of every proc_handler.
sysctl: Remove CTL_NONE and CTL_UNNUMBERED
sysctl: kill dead ctl_handler definitions.
sysctl: Remove the last of the generic binary sysctl support
sysctl net: Remove unused binary sysctl code
sysctl security/tomoyo: Don't look at ctl_name
sysctl arm: Remove binary sysctl support
sysctl x86: Remove dead binary sysctl support
sysctl sh: Remove dead binary sysctl support
sysctl powerpc: Remove dead binary sysctl support
sysctl ia64: Remove dead binary sysctl support
sysctl s390: Remove dead sysctl binary support
sysctl frv: Remove dead binary sysctl support
sysctl mips/lasat: Remove dead binary sysctl support
sysctl drivers: Remove dead binary sysctl support
sysctl crypto: Remove dead binary sysctl support
sysctl security/keys: Remove dead binary sysctl support
sysctl kernel: Remove binary sysctl logic
...
This driver implements support for on-chip Embedded Tracing Macrocell and
Embedded Trace Buffer. It allows to trigger tracing of kernel execution flow
and exporting trace output to userspace via character device and a sysrq
combo.
Trace output can then be decoded by a fairly simple open source tool [1]
which is already sufficient to get the idea of what the kernel is doing.
[1]: http://github.com/virtuoso/etm2human
Signed-off-by: Alexander Shishkin <virtuoso@slind.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This patch is mostly a straightforward translation. The primary side
effect to the resulting vmlinux should be to increase the alignment on
the initramfs to the standard PAGE_SIZE from 32 bytes.
Signed-off-by: Nelson Elhage <nelhage@ksplice.com>
Signed-off-by: Tim Abbott <tabbott@ksplice.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This has the consequence of changing the section name used for head
code from ".text.head" to ".head.text". Since this commit changes all
users in the architecture, this change should be harmless.
The .text.head output section is eliminated and the head text code is
included at the start of the .init output section.
Signed-off-by: Tim Abbott <tabbott@ksplice.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Using OABI, the call to put_user in do_signal can fail causing the
calling app to hang.
The solution is to check if put_user fails and force the app to
seg fault in that case.
Tested with multiple sleeping apps/threads (using the nanosleep syscall)
and suspend/resume.
Signed-off-by: janboe <janboe.ye at gmail.com>
Signed-off-by: Jean Pihet <jpihet@mvista.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
For consistency drop & in front of every proc_handler. Explicity
taking the address is unnecessary and it prevents optimizations
like stubbing the proc_handlers to NULL.
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Resolve the conflict between v2.6.32-rc7 where dn_def_dev_handler
gets a small bug fix and the sysctl tree where I am removing all
sysctl strategy routines.
Now that sys_sysctl is a generic wrapper around /proc/sys .ctl_name
and .strategy members of sysctl tables are dead code. Remove them.
Remove a smattering of ctl_names used in sysctl paths,
and kill the ctl_names in the recently added mach-bcmring.
mach-bcmring never should have had sysctl entries with
.ctl_name set. The binary sysctl interface has been frozen
for a long time before that code was merged, to prevent
probmes with conflicts and lack of testing. The sysctl_check
code would have caught this if anyone had ever tested it that way.
So I have simply dropped the binary sysctl support instead of
adding another compat entry into sysctl_binary.c. Going through
/proc/sys/reboot/warm will still work.
Cc: Leo Chen <leochen@broadcom.com>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Use a definition for the cmpxchg SWI instead of hard-coding the number.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Nicolas Pitre <nico@fluxnic.net>
That code was refactored a long time ago, but one particular label
didn't get adjusted properly which broke the listing of supported
machines.
Signed-off-by: Nicolas Pitre <nico@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
If Linux is running in non-secure mode, this register may have been
already initialised and writing to the control register not allowed.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
ARM unwind is known to compile only with EABI and not-buggy compilers.
The problem is not the unwinding information but the -fno-frame-pointer
option added as a result of !CONFIG_FRAME_POINTER. Now we check the
compiler and raise a #warning in case of wrong compiler.
Signed-off-by: Claudio Scordino <claudio@evidence.eu.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The signal restarting code was placed on the user stack when OABI
compatibility is enabled. Unfortunately, with an EABI NX executable,
this results in an attempt to run code from the non-executable stack,
which segfaults the application.
Fix this by placing the code in the vectors page, along side the
signal return code, and directing the application to that code.
Reported-by: saeed bishara <saeed.bishara@gmail.com>
Tested-by: saeed bishara <saeed.bishara@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Defines ELF_CORE_COPY_TASK_REGS so that CPU register information
of every thread is included in coredump. Without this, only the faulting
thread is coredumped.
Cc: Roger Quadros <ext-roger.quadros@nokia.com>
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-by: Mika Westerberg <mika.westerberg@iki.fi>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The 32-bit wide variant of "mov pc, reg" in Thumb-2 is unpredictable
causing improper handling of the undefined instructions not caught by
the kernel. This patch adds a movw_pc macro for such situations
(currently only used in call_fpe).
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Meaning receive multiple messages, reducing the number of syscalls and
net stack entry/exit operations.
Next patches will introduce mechanisms where protocols that want to
optimize this operation will provide an unlocked_recvmsg operation.
This takes into account comments made by:
. Paul Moore: sock_recvmsg is called only for the first datagram,
sock_recvmsg_nosec is used for the rest.
. Caitlin Bestler: recvmmsg now has a struct timespec timeout, that
works in the same fashion as the ppoll one.
If the underlying protocol returns a datagram with MSG_OOB set, this
will make recvmmsg return right away with as many datagrams (+ the OOB
one) it has received so far.
. Rémi Denis-Courmont & Steven Whitehouse: If we receive N < vlen
datagrams and then recvmsg returns an error, recvmmsg will return
the successfully received datagrams, store the error and return it
in the next call.
This paves the way for a subsequent optimization, sk_prot->unlocked_recvmsg,
where we will be able to acquire the lock only at batch start and end, not at
every underlying recvmsg call.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
After m68k's task_thread_info() doesn't refer to current,
it's possible to remove sched.h from interrupt.h and not break m68k!
Many thanks to Heiko Carstens for allowing this.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Make die() better match x86:
- add printing of the last accessed sysfs file
- ensure console_verbose() is called under the lock
- ensure we panic outside of oops_exit()
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
dump_mem and dump_backtrace were both using multiple printk statements
to print each line. With DEBUG_LL enabled, this causes OOPS to become
very difficult to read. Solve this by only using one printk per line.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Instruction fault status register, IFSR, was introduced on ARMv6 to
provide status information about the last insturction fault. It
needed for proper prefetch abort handling.
Now we have three prefetch abort model:
* legacy - for CPUs before ARMv6. They doesn't provide neither
IFSR nor IFAR. We simulate IFSR with section translation fault
status for them to generalize code;
* ARMv6 - provides IFSR, but not IFAR;
* ARMv7 - provides both IFSR and IFAR.
Signed-off-by: Kirill A. Shutemov <kirill@shutemov.name>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
From: David Brown <davidb@quicinc.com>
The ATAG_CORE is allowed to be empty. Although this is handled
by parse_tag_core(), __vet_atags during startup rejects this tag
unless it contains data. Allow the initial tag to be either the
full size, or empty.
Signed-off-by: David Brown <davidb@quicinc.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Commit 181f817eaa introduced some new code to entry-common.S
Sadly, this new code uses 'bx' instruction which is available only on
ARMv5 and higher CPUs. This causes following compilation errors when
building kernel for StrongARM (ARMv4):
arch/arm/kernel/entry-common.S: Assembler messages:
arch/arm/kernel/entry-common.S:129: Error: selected processor does not
support `bx ip'
arch/arm/kernel/entry-common.S:138: Error: selected processor does not
support `bx ip'
Fix these errors by using 'mov pc' instead of 'bx'.
Signed-off-by: Dmitry Artamonow <mad_soft@inbox.ru>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
do_cache_op() uses find_vma() to validate its arguments without holding
any locking. This means that the VMA could vanish beneath us. Fix
this by taking a read lock on mmap_sem.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Fix:
WARNING: vmlinux.o(.text+0x247c): Section mismatch in reference from the function cpu_idle() to the function .cpuexit.text:cpu_die()
The function cpu_idle() references a function in an exit section.
Often the function cpu_die() has valid usage outside the exit section
and the fix is to remove the __cpuexit annotation of cpu_die.
WARNING: vmlinux.o(.cpuexit.text+0x3c): Section mismatch in reference from the function cpu_die() to the function .cpuinit.text:secondary_start_kernel()
The function __cpuexit cpu_die() references
a function __cpuinit secondary_start_kernel().
This is often seen when error handling in the exit function
uses functionality in the init path.
The fix is often to remove the __cpuinit annotation of
secondary_start_kernel() so it may be used outside an init section.
Sam says:
> The annotation of cpu_die() is wrong.
> To be annotated __cpuexit the function shall:
> - be used in exit context and only in exit context with HOTPLUG_CPU=n
> - be used outside exit context with HOTPLUG_CPU=y
So, this also means __cpu_disable(), __cpu_die() and twd_timer_stop() are
also wrong. However, removing __cpuexit from cpu_die() creates:
WARNING: vmlinux.o(.text+0x6834): Section mismatch in reference from the function cpu_die() to the function .cpuinit.text:secondary_start_kernel()
The function cpu_die() references
the function __cpuinit secondary_start_kernel().
This is often because cpu_die lacks a __cpuinit
annotation or the annotation of secondary_start_kernel is wrong.
so fix this using __ref.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
We suffer an unfortunate combination of "features" which makes highmem
support on platforms without hardware TLB maintainence broadcast difficult:
- we need kmap_high_get() support for DMA cache coherence
- this requires kmap_high() to take a spinlock with IRQs disabled
- kmap_high() occasionally calls flush_all_zero_pkmaps() to clear
out old mappings
- flush_all_zero_pkmaps() calls flush_tlb_kernel_range(), which
on s/w IPI'd systems eventually calls smp_call_function_many()
- smp_call_function_many() must not be called with IRQs disabled:
WARNING: at kernel/smp.c:380 smp_call_function_many+0xc4/0x240()
Modules linked in:
Backtrace:
[<c00306f0>] (dump_backtrace+0x0/0x108) from [<c0286e6c>] (dump_stack+0x18/0x1c)
r6:c007cd18 r5:c02ff228 r4:0000017c
[<c0286e54>] (dump_stack+0x0/0x1c) from [<c0053e08>] (warn_slowpath_common+0x50/0x80)
[<c0053db8>] (warn_slowpath_common+0x0/0x80) from [<c0053e50>] (warn_slowpath_null+0x18/0x1c)
r7:00000003 r6:00000001 r5:c1ff4000 r4:c035fa34
[<c0053e38>] (warn_slowpath_null+0x0/0x1c) from [<c007cd18>] (smp_call_function_many+0xc4/0x240)
[<c007cc54>] (smp_call_function_many+0x0/0x240) from [<c007cec0>] (smp_call_function+0x2c/0x38)
[<c007ce94>] (smp_call_function+0x0/0x38) from [<c005980c>] (on_each_cpu+0x1c/0x38)
[<c00597f0>] (on_each_cpu+0x0/0x38) from [<c0031788>] (flush_tlb_kernel_range+0x50/0x58)
r6:00000001 r5:00000800 r4:c05f3590
[<c0031738>] (flush_tlb_kernel_range+0x0/0x58) from [<c009c600>] (flush_all_zero_pkmaps+0xc0/0xe8)
[<c009c540>] (flush_all_zero_pkmaps+0x0/0xe8) from [<c009c6b4>] (kmap_high+0x8c/0x1e0)
[<c009c628>] (kmap_high+0x0/0x1e0) from [<c00364a8>] (kmap+0x44/0x5c)
[<c0036464>] (kmap+0x0/0x5c) from [<c0109dfc>] (cramfs_readpage+0x3c/0x194)
[<c0109dc0>] (cramfs_readpage+0x0/0x194) from [<c0090c14>] (__do_page_cache_readahead+0x1f0/0x290)
[<c0090a24>] (__do_page_cache_readahead+0x0/0x290) from [<c0090ce4>] (ra_submit+0x30/0x38)
[<c0090cb4>] (ra_submit+0x0/0x38) from [<c0089384>] (filemap_fault+0x3dc/0x438)
r4:c1819988
[<c0088fa8>] (filemap_fault+0x0/0x438) from [<c009d21c>] (__do_fault+0x58/0x43c)
[<c009d1c4>] (__do_fault+0x0/0x43c) from [<c009e8cc>] (handle_mm_fault+0x104/0x318)
[<c009e7c8>] (handle_mm_fault+0x0/0x318) from [<c0033c98>] (do_page_fault+0x188/0x1e4)
[<c0033b10>] (do_page_fault+0x0/0x1e4) from [<c0033ddc>] (do_translation_fault+0x7c/0x84)
[<c0033d60>] (do_translation_fault+0x0/0x84) from [<c002b474>] (do_DataAbort+0x40/0xa4)
r8:c1ff5e20 r7:c0340120 r6:00000805 r5:c1ff5e54 r4:c03400d0
[<c002b434>] (do_DataAbort+0x0/0xa4) from [<c002bcac>] (__dabt_svc+0x4c/0x60)
...
So we disable highmem support on these systems.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Commit 200b812d00 "Clear the exclusive monitor when returning from an
exception" broke the vast majority of ARM systems in the wild which are
still pre ARMv6. The kernel is crashing on the first occurrence of an
exception due to the removal of the actual return instruction for them.
Let's add it back.
Signed-off-by: Nicolas Pitre <nico@marvell.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
