Without the ability to atomically write 16 bytes, we can not update the
middle slot of a bundle, slot 1, unless we stop the machine first. This
patch will ensure the ability to robustly insert and remove a kprobe by
refusing to insert a kprobe on slot 1 until a mechanism is in place to
safely handle this case.
Signed-off-by: Rusty Lynch <rusty.lynch@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The following is a patch provided by Ananth Mavinakayanahalli that implements
the new PPC64 specific parts of the new function return probe design.
NOTE: Since getting Ananth's patch, I changed trampoline_probe_handler()
to consume each of the outstanding return probem instances (feedback
on my original RFC after Ananth cut a patch), and also added the
arch_init() function (adding arch specific initialization.) I have
cross compiled but have not testing this on a PPC64 machine.
Changes include:
* Addition of kretprobe_trampoline to act as a dummy function for instrumented
functions to return to, and for the return probe infrastructure to place
a kprobe on on, gaining control so that the return probe handler
can be called, and so that the instruction pointer can be moved back
to the original return address.
* Addition of arch_init(), allowing a kprobe to be registered on
kretprobe_trampoline
* Addition of trampoline_probe_handler() which is used as the pre_handler
for the kprobe inserted on kretprobe_implementation. This is the function
that handles the details for calling the return probe handler function
and returning control back at the original return address
* Addition of arch_prepare_kretprobe() which is setup as the pre_handler
for a kprobe registered at the beginning of the target function by
kernel/kprobes.c so that a return probe instance can be setup when
a caller enters the target function. (A return probe instance contains
all the needed information for trampoline_probe_handler to do it's job.)
* Hooks added to the exit path of a task so that we can cleanup any left-over
return probe instances (i.e. if a task dies while inside a targeted function
then the return probe instance was reserved at the beginning of the function
but the function never returns so we need to mark the instance as unused.)
Signed-off-by: Rusty Lynch <rusty.lynch@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The following patch implements function return probes for ia64 using
the revised design. With this new design we no longer need to do some
of the odd hacks previous required on the last ia64 return probe port
that I sent out for comments.
Note that this new implementation still does not resolve the problem noted
by Keith Owens where backtrace data is lost after a return probe is hit.
Changes include:
* Addition of kretprobe_trampoline to act as a dummy function for instrumented
functions to return to, and for the return probe infrastructure to place
a kprobe on on, gaining control so that the return probe handler
can be called, and so that the instruction pointer can be moved back
to the original return address.
* Addition of arch_init(), allowing a kprobe to be registered on
kretprobe_trampoline
* Addition of trampoline_probe_handler() which is used as the pre_handler
for the kprobe inserted on kretprobe_implementation. This is the function
that handles the details for calling the return probe handler function
and returning control back at the original return address
* Addition of arch_prepare_kretprobe() which is setup as the pre_handler
for a kprobe registered at the beginning of the target function by
kernel/kprobes.c so that a return probe instance can be setup when
a caller enters the target function. (A return probe instance contains
all the needed information for trampoline_probe_handler to do it's job.)
* Hooks added to the exit path of a task so that we can cleanup any left-over
return probe instances (i.e. if a task dies while inside a targeted function
then the return probe instance was reserved at the beginning of the function
but the function never returns so we need to mark the instance as unused.)
Signed-off-by: Rusty Lynch <rusty.lynch@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The following patch contains the x86_64 specific changes for the new
return probe design. Changes include:
* Removing the architecture specific functions for querying a return probe
instance off a stack address
* Complete rework onf arch_prepare_kretprobe() and trampoline_probe_handler()
* Removing trampoline_post_handler()
* Adding arch_init() so that now we handle registering the return probe
trampoline instead of kernel/kprobes.c doing it
NOTE:
Note that with this new design, the dependency on calculating a pointer to
the task off the stack pointer no longer exist (resolving the problem of
interruption stacks as pointed out in the original feedback to this port.)
Signed-off-by: Rusty Lynch <rusty.lynch@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The following patch contains the i386 specific changes for the new
return probe design. Changes include:
* Removing the architecture specific functions for querying a return probe
instance off a stack address
* Complete rework onf arch_prepare_kretprobe() and trampoline_probe_handler()
* Removing trampoline_post_handler()
* Adding arch_init() so that now we handle registering the return probe
trampoline instead of kernel/kprobes.c doing it
Signed-off-by: Rusty Lynch <rusty.lynch@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Now that PPC64 has no-execute support, here is a second try to fix the
single step out of line during kprobe execution. Kprobes on x86_64 already
solved this problem by allocating an executable page and using it as the
scratch area for stepping out of line. Reuse that.
Signed-off-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
I believe at least for seccomp it's worth to turn off the tsc, not just for
HT but for the L2 cache too. So it's up to you, either you turn it off
completely (which isn't very nice IMHO) or I recommend to apply this below
patch.
This has been tested successfully on x86-64 against current cogito
repository (i686 compiles so I didn't bother testing ;). People selling
the cpu through cpushare may appreciate this bit for a peace of mind.
There's no way to get any timing info anymore with this applied
(gettimeofday is forbidden of course). The seccomp environment is
completely deterministic so it can't be allowed to get timing info, it has
to be deterministic so in the future I can enable a computing mode that
does a parallel computing for each task with server side transparent
checkpointing and verification that the output is the same from all the 2/3
seller computers for each task, without the buyer even noticing (for now
the verification is left to the buyer client side and there's no
checkpointing, since that would require more kernel changes to track the
dirty bits but it'll be easy to extend once the basic mode is finished).
Eliminating a cold-cache read of the cr4 global variable will save one
cacheline during the tlb flush while making the code per-cpu-safe at the
same time. Thanks to Mikael Pettersson for noticing the tlb flush wasn't
per-cpu-safe.
The global tlb flush can run from irq (IPI calling do_flush_tlb_all) but
it'll be transparent to the switch_to code since the IPI won't make any
change to the cr4 contents from the point of view of the interrupted code
and since it's now all per-cpu stuff, it will not race. So no need to
disable irqs in switch_to slow path.
Signed-off-by: Andrea Arcangeli <andrea@cpushare.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch adds a couple of missing symbol exports. flush_dcache_page is
used by the AGP driver and rtc_lock by the RTC driver.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch removes CONFIG_PMAC_PBOOK (PowerBook support). This is now
split into CONFIG_PMAC_MEDIABAY for the actual hotswap bay that some
powerbooks have, CONFIG_PM for power management related code, and just left
out of any CONFIG_* option for some generally useful stuff that can be used
on non-laptops as well.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The Power Management Unit on PowerMacs is very sensitive to timeouts during
async message exchanges. It uses rather crude protocol based on a shift
register with an interrupt and is almost continuously exchanging messages with
the host CPU on laptops.
This patch adds a routine to the open_pic driver to be able to select a PMU
driver so that it bumps it's interrupt priority to above the normal level.
This will allow PMU interrupts to occur while another interrupt is pending,
and thus reduce the risk of machine beeing abruptly shutdown by the PMU due to
a timeout in PMU communication caused by excessive interrupt latency. The
problem is very rare, and usually just doesn't happen, but it is still useful
to make things even more robust.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The proposed _tlbie call at update_mmu_cache() is safe because:
Addresses for which update_mmu_cache() gets invocated are never inside the
static kernel virtual mapping, meaning that there is no risk for the
_tlbie() here to be thrashing the pinned entry, as Dan suspected.
The intermediate TLB state in which this bug can be triggered is not
visible by userspace or any other contexts, except the page fault handling
path. So there is no need to worry about userspace dcbxxx users.
The other solution to this is to avoid dcbst misbehaviour in the first
place, which involves changing in-kernel "dcbst" callers to use 8xx
specific SPR's.
Summary:
On 8xx, cache control instructions (particularly "dcbst" from
flush_dcache_icache) fault as write operation if there is an unpopulated
TLB entry for the address in question. To workaround that, we invalidate
the TLB here, thus avoiding dcbst misbehaviour.
Signed-off-by: Marcelo Tosatti <marcelo.tosatti@cyclades.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
arch/mips/kernel/signal.c: In function 'do_signal':
arch/mips/kernel/signal.c:460: error: too many arguments to function 'try_to_freeze'
Signed-off-by: Yoichi Yuasa <yuasa@hh.iij4u.or.jp>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Lost a curly brace in translation. Everything is better now.
Signed-off-by: Matt McClintock <msm@freescale.com>
Signed-off-by: Kumar Gala <kumar.gala@freescale.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Various USB patches, mostly for portability:
- Fifo mode 1 didn't work previously (oopsed), so now it's fixed and
(why not) defines even more endpoints for composite devices.
- OMAP 1710 doesn't have an internal transceiver.
- Small PM update: if the USB link is suspended, don't disconnect on
entry to deep sleep.
- Be more correct about handling zero length control reads. OMAP
seems to mis-handle that protocol peculiarity though; best avoided.
- Platform device resources (for UDC and OTG controllers) now use
physical addresses, so /proc/iomem is more consistent.
- Minor cleanups, notably (by volume) for "sparse" NULL warnings.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
This updates the CFQ io scheduler to the new time sliced design (cfq
v3). It provides full process fairness, while giving excellent
aggregate system throughput even for many competing processes. It
supports io priorities, either inherited from the cpu nice value or set
directly with the ioprio_get/set syscalls. The latter closely mimic
set/getpriority.
This import is based on my latest from -mm.
Signed-off-by: Jens Axboe <axboe@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
It doesn't make sense for this to be in mm-armv.c now that 26-bit
ARM support is no longer integrated into arch/arm.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
It doesn't make sense to have the PGD kernel pointers initialisation
separate from the PGD user pointers, especially when we clean the
data cache over the whole range.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This call allows the dynamic tick support to reprogram the timer
immediately before the CPU idles.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Lennert Buytenhek
Compiling one kernel that supports both ixdp2400 and ixdp2800 gives
an error, as a copy of the ixdp2400 irq init routing accidentally
ended up in ixdp2800.c somehow.
Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: Deepak Saxena
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Lennert Buytenhek
Add a mapping for the ixp2400 and ixp2800 msf unit. The msf is the
ixp2000's 'media and switch fabric' unit, which handles the networking
part of the chip.
Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: Deepak Saxena
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
VST needs to know which timer handler is for the timer interrupt.
Mark all timer interrupts with the SA_TIMER flag.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The pending registers for IRQ1-IRQ7 were pointing to the interrupt pending
register instead of the external one.
Signed-off-by: Tony Li <Tony.Li@freescale.com>
Signed-off-by: Kumar Gala <kumar.gala@freescale.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Another swsusp fixup.
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
1. Establish a simple API for process freezing defined in linux/include/sched.h:
frozen(process) Check for frozen process
freezing(process) Check if a process is being frozen
freeze(process) Tell a process to freeze (go to refrigerator)
thaw_process(process) Restart process
frozen_process(process) Process is frozen now
2. Remove all references to PF_FREEZE and PF_FROZEN from all
kernel sources except sched.h
3. Fix numerous locations where try_to_freeze is manually done by a driver
4. Remove the argument that is no longer necessary from two function calls.
5. Some whitespace cleanup
6. Clear potential race in refrigerator (provides an open window of PF_FREEZE
cleared before setting PF_FROZEN, recalc_sigpending does not check
PF_FROZEN).
This patch does not address the problem of freeze_processes() violating the rule
that a task may only modify its own flags by setting PF_FREEZE. This is not clean
in an SMP environment. freeze(process) is therefore not SMP safe!
Signed-off-by: Christoph Lameter <christoph@lameter.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
printk() calls should include appropriate KERN_* constant.
Signed-off-by: Christophe Lucas <clucas@rotomalug.org>
Signed-off-by: Domen Puncer <domen@coderock.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
printk() calls should include appropriate KERN_* constant.
Signed-off-by: Christophe Lucas <clucas@rotomalug.org>
Signed-off-by: Domen Puncer <domen@coderock.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
fix a comment about the array size.
Signed-off-by: Olaf Hering <olh@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
There are currently two different boot_cpu_logical_apicid variables:
- a global one in mpparse.c
- a static one in smpboot.c
Of these two, only the one in smpboot.c might be used (through
boot_cpu_apicid).
This patch therefore removes the one in mpparse.c .
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrey Panin <pazke@donpac.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Remove some of the unnecessary differences between arch/i386 and
arch/x86_64. This patch fixes more whitespace issues, some miscellaneous
typos, a wrong URL and a factually incorrect statement about the current
boot sector code.
Signed-off-by: Domen Puncer <domen@coderock.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Put function prototypes for memset() and memcpy() ahead of where
there are used, to kill sparse warnings:
arch/x86_64/boot/compressed/../../../../lib/inflate.c:317:3: warning: undefined identifier 'memset'
arch/x86_64/boot/compressed/../../../../lib/inflate.c:601:11: warning: undefined identifier 'memcpy'
arch/x86_64/boot/compressed/misc.c:151:2: warning: undefined identifier 'memcpy'
arch/x86_64/boot/compressed/../../../../lib/inflate.c:317:3: warning: call with no type!
arch/x86_64/boot/compressed/../../../../lib/inflate.c:601:17: warning: call with no type!
arch/x86_64/boot/compressed/misc.c:151:9: warning: call with no type!
Signed-off-by: randy_dunlap <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
o Following patch provides purely cosmetic changes and corrects CodingStyle
guide lines related certain issues like below in kexec related files
o braces for one line "if" statements, "for" loops,
o more than 80 column wide lines,
o No space after "while", "for" and "switch" key words
o Changes:
o take-2: Removed the extra tab before "case" key words.
o take-3: Put operator at the end of line and space before "*/"
Signed-off-by: Maneesh Soni <maneesh@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
If we are faulting in kernel it is quite possible this will lead to a
panic. Save trap number, cr2 (in case of page fault) and error_code in the
current thread (these fields already exist for signal delivery but are not
used here).
This helps later kdump crash analyzing from user-space (a script has been
submitted to dig this info out in gdb).
Signed-off-by: Alexander Nyberg <alexn@telia.com>
Cc: <fastboot@lists.osdl.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Makes kexec_crashdump() take a pt_regs * as an argument. This allows to
get exact register state at the point of the crash. If we come from direct
panic assertion NULL will be passed and the current registers saved before
crashdump.
This hooks into two places:
die(): check the conditions under which we will panic when calling
do_exit and go there directly with the pt_regs that caused the fatal
fault.
die_nmi(): If we receive an NMI lockup while in the kernel use the
pt_regs and go directly to crash_kexec(). We're probably nested up badly
at this point so this might be the only chance to escape with proper
information.
Signed-off-by: Alexander Nyberg <alexn@telia.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch adds support for retrieving the address of elf core header if one
is passed in command line.
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch provides the interfaces necessary to read the dump contents,
treating it as a high memory device.
Signed off by Hariprasad Nellitheertha <hari@in.ibm.com>
Signed-off-by: Eric Biederman <ebiederm@xmission.com>
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
- config option CONFIG_CRASH_DUMP
- Made it dependent on HIGHMEM. This is required as capture kernel treats
the previous kernel's memory as high memmory and stitches a PTE for
accessing it.
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch retrieves the max_pfn being used by previous kernel and stores it
in a safe location (saved_max_pfn) before it is overwritten due to user
defined memory map. This pfn is used to make sure that user does not try to
read the physical memory beyond saved_max_pfn.
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
o Problem: Kexec on panic hangs if first kernel is booted with nmi_watchdog
command line parameter. This problem occurs because kexec crash shutdown
code replaces the NMI callback handler. This handler saves the cpu register
states and halts the cpu. If system is booted with nmi_watchdog parameter,
then crashing cpu also runs this nmi handler and halts itself.
o This patch fixes the problem by keeping a track of crashing cpu and not
executing the new nmi handler on crashing cpu.
o There is a dependence on smp_processor_id() function which might return
insane value for cpu, if cpu field of thread_info is corrupted.
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
