27 Apr, 2020
1 commit
-
Instead of having all the sysctl handlers deal with user pointers, which
is rather hairy in terms of the BPF interaction, copy the input to and
from userspace in common code. This also means that the strings are
always NUL-terminated by the common code, making the API a little bit
safer.As most handler just pass through the data to one of the common handlers
a lot of the changes are mechnical.Signed-off-by: Christoph Hellwig
Acked-by: Andrey Ignatov
Signed-off-by: Al Viro
17 Jul, 2019
1 commit
-
Architectures which support kprobes have very similar boilerplate around
calling kprobe_fault_handler(). Use a helper function in kprobes.h to
unify them, based on the x86 code.This changes the behaviour for other architectures when preemption is
enabled. Previously, they would have disabled preemption while calling
the kprobe handler. However, preemption would be disabled if this fault
was due to a kprobe, so we know the fault was not due to a kprobe
handler and can simply return failure.This behaviour was introduced in commit a980c0ef9f6d ("x86/kprobes:
Refactor kprobes_fault() like kprobe_exceptions_notify()")[anshuman.khandual@arm.com: export kprobe_fault_handler()]
Link: http://lkml.kernel.org/r/1561133358-8876-1-git-send-email-anshuman.khandual@arm.com
Link: http://lkml.kernel.org/r/1560420444-25737-1-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual
Reviewed-by: Dave Hansen
Cc: Michal Hocko
Cc: Matthew Wilcox
Cc: Mark Rutland
Cc: Christophe Leroy
Cc: Stephen Rothwell
Cc: Andrey Konovalov
Cc: Michael Ellerman
Cc: Paul Mackerras
Cc: Russell King
Cc: Catalin Marinas
Cc: Will Deacon
Cc: Tony Luck
Cc: Fenghua Yu
Cc: Martin Schwidefsky
Cc: Heiko Carstens
Cc: Yoshinori Sato
Cc: "David S. Miller"
Cc: Thomas Gleixner
Cc: Peter Zijlstra
Cc: Ingo Molnar
Cc: Andy Lutomirski
Cc: Vineet Gupta
Cc: James Hogan
Cc: Paul Burton
Cc: Ralf Baechle
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
31 May, 2019
1 commit
-
Based on 1 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version this program is distributed in the
hope that it will be useful but without any warranty without even
the implied warranty of merchantability or fitness for a particular
purpose see the gnu general public license for more details you
should have received a copy of the gnu general public license along
with this program if not write to the free software foundation inc
59 temple place suite 330 boston ma 02111 1307 usaextracted by the scancode license scanner the SPDX license identifier
GPL-2.0-or-later
has been chosen to replace the boilerplate/reference in 1334 file(s).
Signed-off-by: Thomas Gleixner
Reviewed-by: Allison Randal
Reviewed-by: Richard Fontana
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.113240726@linutronix.de
Signed-off-by: Greg Kroah-Hartman
19 Apr, 2019
1 commit
-
Verify the stack frame pointer on kretprobe trampoline handler,
If the stack frame pointer does not match, it skips the wrong
entry and tries to find correct one.This can happen if user puts the kretprobe on the function
which can be used in the path of ftrace user-function call.
Such functions should not be probed, so this adds a warning
message that reports which function should be blacklisted.Tested-by: Andrea Righi
Signed-off-by: Masami Hiramatsu
Acked-by: Steven Rostedt
Cc: Linus Torvalds
Cc: Mathieu Desnoyers
Cc: Peter Zijlstra
Cc: Thomas Gleixner
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/155094059185.6137.15527904013362842072.stgit@devbox
Signed-off-by: Ingo Molnar
30 Jan, 2019
1 commit
-
Remove the ifdeffery in the breakpoint parsing arch_build_bp_info() by
adding a within_kprobe_blacklist() stub for the !CONFIG_KPROBES case.It is returning true when kprobes are not enabled to mean that any
address is within the kprobes blacklist on such kernels and thus not
allow kernel breakpoints on non-kprobes kernels.Signed-off-by: Borislav Petkov
Acked-by: Masami Hiramatsu
Cc: Anil S Keshavamurthy
Cc: "David S. Miller"
Cc: Frederic Weisbecker
Cc: "H. Peter Anvin"
Cc: Ingo Molnar
Cc: "Naveen N. Rao"
Cc: Thomas Gleixner
Link: https://lkml.kernel.org/r/20190127131237.4557-1-bp@alien8.de
27 Dec, 2018
1 commit
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Pull x86 cleanups from Ingo Molnar:
"Misc cleanups"* 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/kprobes: Remove trampoline_handler() prototype
x86/kernel: Fix more -Wmissing-prototypes warnings
x86: Fix various typos in comments
x86/headers: Fix -Wmissing-prototypes warning
x86/process: Avoid unnecessary NULL check in get_wchan()
x86/traps: Complete prototype declarations
x86/mce: Fix -Wmissing-prototypes warnings
x86/gart: Rewrite early_gart_iommu_check() comment
18 Dec, 2018
1 commit
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Blacklist symbols in arch-defined probe-prohibited areas.
With this change, user can see all symbols which are prohibited
to probe in debugfs.All archtectures which have custom prohibit areas should define
its own arch_populate_kprobe_blacklist() function, but unless that,
all symbols marked __kprobes are blacklisted.Reported-by: Andrea Righi
Tested-by: Andrea Righi
Signed-off-by: Masami Hiramatsu
Cc: Andy Lutomirski
Cc: Anil S Keshavamurthy
Cc: Borislav Petkov
Cc: David S. Miller
Cc: Linus Torvalds
Cc: Naveen N. Rao
Cc: Peter Zijlstra
Cc: Thomas Gleixner
Cc: Yonghong Song
Link: http://lkml.kernel.org/r/154503485491.26176.15823229545155174796.stgit@devbox
Signed-off-by: Ingo Molnar
08 Dec, 2018
1 commit
-
... with the goal of eventually enabling -Wmissing-prototypes by
default. At least on x86.Make functions static where possible, otherwise add prototypes or make
them visible through includes.asm/trace/ changes courtesy of Steven Rostedt .
Signed-off-by: Borislav Petkov
Reviewed-by: Masami Hiramatsu
Reviewed-by: Ingo Molnar
Acked-by: Rafael J. Wysocki # ACPI + cpufreq bits
Cc: Andrew Banman
Cc: Dimitri Sivanich
Cc: "H. Peter Anvin"
Cc: Ingo Molnar
Cc: Masami Hiramatsu
Cc: Mike Travis
Cc: "Steven Rostedt (VMware)"
Cc: Thomas Gleixner
Cc: Yi Wang
Cc: linux-acpi@vger.kernel.org
21 Jun, 2018
2 commits
-
Remove jprobe stub APIs from linux/kprobes.h since
the jprobe implementation was completely gone.Signed-off-by: Masami Hiramatsu
Acked-by: Thomas Gleixner
Cc: Ananth N Mavinakayanahalli
Cc: Andrew Morton
Cc: Linus Torvalds
Cc: Peter Zijlstra
Cc: Steven Rostedt
Cc: linux-arch@vger.kernel.org
Link: https://lore.kernel.org/lkml/152942503572.15209.1652552217914694917.stgit@devbox
Signed-off-by: Ingo Molnar -
Remove functionally empty jprobe API implementations and test cases.
Signed-off-by: Masami Hiramatsu
Acked-by: Thomas Gleixner
Cc: Ananth N Mavinakayanahalli
Cc: Andrew Morton
Cc: Linus Torvalds
Cc: Peter Zijlstra
Cc: Steven Rostedt
Cc: linux-arch@vger.kernel.org
Link: https://lore.kernel.org/lkml/152942430705.15209.2307050500995264322.stgit@devbox
Signed-off-by: Ingo Molnar
13 Nov, 2017
1 commit
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The jprobes APIs are deprecated - but are still in occasional use for code that
few people seem to care about, so stop generating deprecation warnings.Cc: Masami Hiramatsu
Cc: Linus Torvalds
Cc: Peter Zijlstra
Cc: Thomas Gleixner
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar
20 Oct, 2017
1 commit
-
Disable the jprobes APIs and comment out the jprobes API function
code. This is in preparation of removing all jprobes related
code (including kprobe's break_handler).Nowadays ftrace and other tracing features are mature enough
to replace jprobes use-cases. Users can safely use ftrace and
perf probe etc. for their use cases.Signed-off-by: Masami Hiramatsu
Cc: Alexei Starovoitov
Cc: Ananth N Mavinakayanahalli
Cc: Anil S Keshavamurthy
Cc: David S . Miller
Cc: Ian McDonald
Cc: Kees Cook
Cc: Linus Torvalds
Cc: Paul E . McKenney
Cc: Peter Zijlstra
Cc: Stephen Hemminger
Cc: Steven Rostedt
Cc: Thomas Gleixner
Cc: Vlad Yasevich
Link: http://lkml.kernel.org/r/150724527741.5014.15465541485637899227.stgit@devbox
Signed-off-by: Ingo Molnar
08 Jul, 2017
1 commit
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Rename function_offset_within_entry() to scope it to kprobe namespace by
using kprobe_ prefix, and to also simplify it.Suggested-by: Ingo Molnar
Suggested-by: Masami Hiramatsu
Signed-off-by: Naveen N. Rao
Cc: Ananth N Mavinakayanahalli
Cc: Linus Torvalds
Cc: Peter Zijlstra
Cc: Thomas Gleixner
Link: http://lkml.kernel.org/r/3aa6c7e2e4fb6e00f3c24fa306496a66edb558ea.1499443367.git.naveen.n.rao@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar
18 May, 2017
1 commit
-
Enabling the tracer selftest triggers occasionally the warning in
text_poke(), which warns when the to be modified page is not marked
reserved.The reason is that the tracer selftest installs kprobes on functions marked
__init for testing. These probes are removed after the tests, but that
removal schedules the delayed kprobes_optimizer work, which will do the
actual text poke. If the work is executed after the init text is freed,
then the warning triggers. The bug can be reproduced reliably when the work
delay is increased.Flush the optimizer work and wait for the optimizing/unoptimizing lists to
become empty before returning from the kprobes tracer selftest. That
ensures that all operations which were queued due to the probes removal
have completed.Link: http://lkml.kernel.org/r/20170516094802.76a468bb@gandalf.local.home
Signed-off-by: Thomas Gleixner
Acked-by: Masami Hiramatsu
Cc: stable@vger.kernel.org
Fixes: 6274de498 ("kprobes: Support delayed unoptimizing")
Signed-off-by: Steven Rostedt (VMware)
06 May, 2017
1 commit
-
Pull powerpc updates from Michael Ellerman:
"Highlights include:- Larger virtual address space on 64-bit server CPUs. By default we
use a 128TB virtual address space, but a process can request access
to the full 512TB by passing a hint to mmap().- Support for the new Power9 "XIVE" interrupt controller.
- TLB flushing optimisations for the radix MMU on Power9.
- Support for CAPI cards on Power9, using the "Coherent Accelerator
Interface Architecture 2.0".- The ability to configure the mmap randomisation limits at build and
runtime.- Several small fixes and cleanups to the kprobes code, as well as
support for KPROBES_ON_FTRACE.- Major improvements to handling of system reset interrupts,
correctly treating them as NMIs, giving them a dedicated stack and
using a new hypervisor call to trigger them, all of which should
aid debugging and robustness.- Many fixes and other minor enhancements.
Thanks to: Alastair D'Silva, Alexey Kardashevskiy, Alistair Popple,
Andrew Donnellan, Aneesh Kumar K.V, Anshuman Khandual, Anton
Blanchard, Balbir Singh, Ben Hutchings, Benjamin Herrenschmidt,
Bhupesh Sharma, Chris Packham, Christian Zigotzky, Christophe Leroy,
Christophe Lombard, Daniel Axtens, David Gibson, Gautham R. Shenoy,
Gavin Shan, Geert Uytterhoeven, Guilherme G. Piccoli, Hamish Martin,
Hari Bathini, Kees Cook, Laurent Dufour, Madhavan Srinivasan, Mahesh J
Salgaonkar, Mahesh Salgaonkar, Masami Hiramatsu, Matt Brown, Matthew
R. Ochs, Michael Neuling, Naveen N. Rao, Nicholas Piggin, Oliver
O'Halloran, Pan Xinhui, Paul Mackerras, Rashmica Gupta, Russell
Currey, Sukadev Bhattiprolu, Thadeu Lima de Souza Cascardo, Tobin C.
Harding, Tyrel Datwyler, Uma Krishnan, Vaibhav Jain, Vipin K Parashar,
Yang Shi"* tag 'powerpc-4.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (214 commits)
powerpc/64s: Power9 has no LPCR[VRMASD] field so don't set it
powerpc/powernv: Fix TCE kill on NVLink2
powerpc/mm/radix: Drop support for CPUs without lockless tlbie
powerpc/book3s/mce: Move add_taint() later in virtual mode
powerpc/sysfs: Move #ifdef CONFIG_HOTPLUG_CPU out of the function body
powerpc/smp: Document irq enable/disable after migrating IRQs
powerpc/mpc52xx: Don't select user-visible RTAS_PROC
powerpc/powernv: Document cxl dependency on special case in pnv_eeh_reset()
powerpc/eeh: Clean up and document event handling functions
powerpc/eeh: Avoid use after free in eeh_handle_special_event()
cxl: Mask slice error interrupts after first occurrence
cxl: Route eeh events to all drivers in cxl_pci_error_detected()
cxl: Force context lock during EEH flow
powerpc/64: Allow CONFIG_RELOCATABLE if COMPILE_TEST
powerpc/xmon: Teach xmon oops about radix vectors
powerpc/mm/hash: Fix off-by-one in comment about kernel contexts ids
powerpc/pseries: Enable VFIO
powerpc/powernv: Fix iommu table size calculation hook for small tables
powerpc/powernv: Check kzalloc() return value in pnv_pci_table_alloc
powerpc: Add arch/powerpc/tools directory
...
20 Apr, 2017
2 commits
-
commit 239aeba76409 ("perf powerpc: Fix kprobe and kretprobe handling with
kallsyms on ppc64le") changed how we use the offset field in struct kprobe on
ABIv2. perf now offsets from the global entry point if an offset is specified
and otherwise chooses the local entry point.Fix the same in kernel for kprobe API users. We do this by extending
kprobe_lookup_name() to accept an additional parameter to indicate the offset
specified with the kprobe registration. If offset is 0, we return the local
function entry and return the global entry point otherwise.With:
# cd /sys/kernel/debug/tracing/
# echo "p _do_fork" >> kprobe_events
# echo "p _do_fork+0x10" >> kprobe_eventsbefore this patch:
# cat ../kprobes/list
c0000000000d0748 k _do_fork+0x8 [DISABLED]
c0000000000d0758 k _do_fork+0x18 [DISABLED]
c0000000000412b0 k kretprobe_trampoline+0x0 [OPTIMIZED]and after:
# cat ../kprobes/list
c0000000000d04c8 k _do_fork+0x8 [DISABLED]
c0000000000d04d0 k _do_fork+0x10 [DISABLED]
c0000000000412b0 k kretprobe_trampoline+0x0 [OPTIMIZED]Acked-by: Ananth N Mavinakayanahalli
Signed-off-by: Naveen N. Rao
Signed-off-by: Michael Ellerman -
The macro is now pretty long and ugly on powerpc. In the light of further
changes needed here, convert it to a __weak variant to be over-ridden with a
nicer looking function.Suggested-by: Masami Hiramatsu
Acked-by: Masami Hiramatsu
Signed-off-by: Naveen N. Rao
Signed-off-by: Michael Ellerman
16 Mar, 2017
1 commit
-
perf specifies an offset from _text and since this offset is fed
directly into the arch-specific helper, kprobes tracer rejects
installation of kretprobes through perf. Fix this by looking up the
actual offset from a function for the specified sym+offset.Refactor and reuse existing routines to limit code duplication -- we
repurpose kprobe_addr() for determining final kprobe address and we
split out the function entry offset determination into a separate
generic helper.Before patch:
naveen@ubuntu:~/linux/tools/perf$ sudo ./perf probe -v do_open%return
probe-definition(0): do_open%return
symbol:do_open file:(null) line:0 offset:0 return:1 lazy:(null)
0 arguments
Looking at the vmlinux_path (8 entries long)
Using /boot/vmlinux for symbols
Open Debuginfo file: /boot/vmlinux
Try to find probe point from debuginfo.
Matched function: do_open [2d0c7ff]
Probe point found: do_open+0
Matched function: do_open [35d76dc]
found inline addr: 0xc0000000004ba9c4
Failed to find "do_open%return",
because do_open is an inlined function and has no return point.
An error occurred in debuginfo analysis (-22).
Trying to use symbols.
Opening /sys/kernel/debug/tracing//README write=0
Opening /sys/kernel/debug/tracing//kprobe_events write=1
Writing event: r:probe/do_open _text+4469776
Failed to write event: Invalid argument
Error: Failed to add events. Reason: Invalid argument (Code: -22)
naveen@ubuntu:~/linux/tools/perf$ dmesg | tail
[ 33.568656] Given offset is not valid for return probe.After patch:
naveen@ubuntu:~/linux/tools/perf$ sudo ./perf probe -v do_open%return
probe-definition(0): do_open%return
symbol:do_open file:(null) line:0 offset:0 return:1 lazy:(null)
0 arguments
Looking at the vmlinux_path (8 entries long)
Using /boot/vmlinux for symbols
Open Debuginfo file: /boot/vmlinux
Try to find probe point from debuginfo.
Matched function: do_open [2d0c7d6]
Probe point found: do_open+0
Matched function: do_open [35d76b3]
found inline addr: 0xc0000000004ba9e4
Failed to find "do_open%return",
because do_open is an inlined function and has no return point.
An error occurred in debuginfo analysis (-22).
Trying to use symbols.
Opening /sys/kernel/debug/tracing//README write=0
Opening /sys/kernel/debug/tracing//kprobe_events write=1
Writing event: r:probe/do_open _text+4469808
Writing event: r:probe/do_open_1 _text+4956344
Added new events:
probe:do_open (on do_open%return)
probe:do_open_1 (on do_open%return)You can now use it in all perf tools, such as:
perf record -e probe:do_open_1 -aR sleep 1
naveen@ubuntu:~/linux/tools/perf$ sudo cat /sys/kernel/debug/kprobes/list
c000000000041370 k kretprobe_trampoline+0x0 [OPTIMIZED]
c0000000004ba0b8 r do_open+0x8 [DISABLED]
c000000000443430 r do_open+0x0 [DISABLED]Signed-off-by: Naveen N. Rao
Acked-by: Masami Hiramatsu
Cc: Ananth N Mavinakayanahalli
Cc: Michael Ellerman
Cc: Steven Rostedt
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lkml.kernel.org/r/d8cd1ef420ec22e3643ac332fdabcffc77319a42.1488961018.git.naveen.n.rao@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo
04 Mar, 2017
1 commit
-
kretprobes can be registered by specifying an absolute address or by
specifying offset to a symbol. However, we need to ensure this falls at
function entry so as to be able to determine the return address.Validate the same during kretprobe registration. By default, there
should not be any offset from a function entry, as determined through a
kallsyms_lookup(). Introduce arch_function_offset_within_entry() as a
way for architectures to override this.Signed-off-by: Naveen N. Rao
Acked-by: Masami Hiramatsu
Cc: Ananth N Mavinakayanahalli
Cc: Michael Ellerman
Cc: Steven Rostedt
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lkml.kernel.org/r/f1583bc4839a3862cfc2acefcc56f9c8837fa2ba.1487770934.git.naveen.n.rao@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo
28 Feb, 2017
1 commit
-
Often all is needed is these small helpers, instead of compiler.h or a
full kprobes.h. This is important for asm helpers, in fact even some
asm/kprobes.h make use of these helpers... instead just keep a generic
asm file with helpers useful for asm code with the least amount of
clutter as possible.Likewise we need now to also address what to do about this file for both
when architectures have CONFIG_HAVE_KPROBES, and when they do not. Then
for when architectures have CONFIG_HAVE_KPROBES but have disabled
CONFIG_KPROBES.Right now most asm/kprobes.h do not have guards against CONFIG_KPROBES,
this means most architecture code cannot include asm/kprobes.h safely.
Correct this and add guards for architectures missing them.
Additionally provide architectures that not have kprobes support with
the default asm-generic solution. This lets us force asm/kprobes.h on
the header include/linux/kprobes.h always, but most importantly we can
now safely include just asm/kprobes.h on architecture code without
bringing the full kitchen sink of header files.Two architectures already provided a guard against CONFIG_KPROBES on its
kprobes.h: sh, arch. The rest of the architectures needed gaurds added.
We avoid including any not-needed headers on asm/kprobes.h unless
kprobes have been enabled.In a subsequent atomic change we can try now to remove compiler.h from
include/linux/kprobes.h.During this sweep I've also identified a few architectures defining a
common macro needed for both kprobes and ftrace, that of the definition
of the breakput instruction up. Some refer to this as
BREAKPOINT_INSTRUCTION. This must be kept outside of the #ifdef
CONFIG_KPROBES guard.[mcgrof@kernel.org: fix arm64 build]
Link: http://lkml.kernel.org/r/CAB=NE6X1WMByuARS4mZ1g9+W=LuVBnMDnh_5zyN0CLADaVh=Jw@mail.gmail.com
[sfr@canb.auug.org.au: fixup for kprobes declarations moving]
Link: http://lkml.kernel.org/r/20170214165933.13ebd4f4@canb.auug.org.au
Link: http://lkml.kernel.org/r/20170203233139.32682-1-mcgrof@kernel.org
Signed-off-by: Luis R. Rodriguez
Signed-off-by: Stephen Rothwell
Acked-by: Masami Hiramatsu
Cc: Arnd Bergmann
Cc: Masami Hiramatsu
Cc: Ananth N Mavinakayanahalli
Cc: Anil S Keshavamurthy
Cc: David S. Miller
Cc: Ingo Molnar
Cc: Thomas Gleixner
Cc: H. Peter Anvin
Cc: Andy Lutomirski
Cc: Steven Rostedt
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
14 Jan, 2017
1 commit
-
Improve __kernel_text_address()/kernel_text_address() to return
true if the given address is on a kprobe's instruction slot
trampoline.This can help stacktraces to determine the address is on a
text area or not.To implement this atomically in is_kprobe_*_slot(), also change
the insn_cache page list to an RCU list.This changes timings a bit (it delays page freeing to the RCU garbage
collection phase), but none of that is in the hot path.Note: this change can add small overhead to stack unwinders because
it adds 2 additional checks to __kernel_text_address(). However, the
impact should be very small, because kprobe_insn_pages list has 1 entry
per 256 probes(on x86, on arm/arm64 it will be 1024 probes),
and kprobe_optinsn_pages has 1 entry per 32 probes(on x86).
In most use cases, the number of kprobe events may be less
than 20, which means that is_kprobe_*_slot() will check just one entry.Tested-by: Josh Poimboeuf
Signed-off-by: Masami Hiramatsu
Acked-by: Peter Zijlstra
Cc: Alexander Shishkin
Cc: Ananth N Mavinakayanahalli
Cc: Andrew Morton
Cc: Andrey Konovalov
Cc: Arnaldo Carvalho de Melo
Cc: Jiri Olsa
Cc: Linus Torvalds
Cc: Thomas Gleixner
Link: http://lkml.kernel.org/r/148388747896.6869.6354262871751682264.stgit@devbox
[ Improved the changelog and coding style. ]
Signed-off-by: Ingo Molnar
04 Aug, 2015
1 commit
-
Code on the kprobe blacklist doesn't want unexpected int3
exceptions. It probably doesn't want unexpected debug exceptions
either. Be safe: disallow breakpoints in nokprobes code.On non-CONFIG_KPROBES kernels, there is no kprobe blacklist. In
that case, disallow kernel breakpoints entirely.It will be particularly important to keep hw breakpoints out of the
entry and NMI code once we move debug exceptions off the IST stack.Signed-off-by: Andy Lutomirski
Signed-off-by: Peter Zijlstra (Intel)
Cc: Borislav Petkov
Cc: Brian Gerst
Cc: Linus Torvalds
Cc: Masami Hiramatsu
Cc: Peter Zijlstra
Cc: Steven Rostedt
Cc: Thomas Gleixner
Link: http://lkml.kernel.org/r/e14b152af99640448d895e3c2a8c2d5ee19a1325.1438312874.git.luto@kernel.org
Signed-off-by: Ingo Molnar
14 Jan, 2015
1 commit
-
Pass the original kprobe for preparing an optimized kprobe arch-dep
part, since for some architecture (e.g. ARM32) requires the information
in original kprobe.Signed-off-by: Masami Hiramatsu
Signed-off-by: Wang Nan
Signed-off-by: Jon Medhurst
27 Oct, 2014
1 commit
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Introduce weak arch_check_ftrace_location() helper function which
architectures can override in order to implement handling of kprobes
on function tracer call sites on their own, without depending on
common code or implementing the KPROBES_ON_FTRACE feature.Signed-off-by: Heiko Carstens
Acked-by: Masami Hiramatsu
Acked-by: Steven Rostedt
Signed-off-by: Martin Schwidefsky
13 Jun, 2014
1 commit
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Pull more perf updates from Ingo Molnar:
"A second round of perf updates:- wide reaching kprobes sanitization and robustization, with the hope
of fixing all 'probe this function crashes the kernel' bugs, by
Masami Hiramatsu.- uprobes updates from Oleg Nesterov: tmpfs support, corner case
fixes and robustization work.- perf tooling updates and fixes from Jiri Olsa, Namhyung Ki, Arnaldo
et al:
* Add support to accumulate hist periods (Namhyung Kim)
* various fixes, refactorings and enhancements"* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (101 commits)
perf: Differentiate exec() and non-exec() comm events
perf: Fix perf_event_comm() vs. exec() assumption
uprobes/x86: Rename arch_uprobe->def to ->defparam, minor comment updates
perf/documentation: Add description for conditional branch filter
perf/x86: Add conditional branch filtering support
perf/tool: Add conditional branch filter 'cond' to perf record
perf: Add new conditional branch filter 'PERF_SAMPLE_BRANCH_COND'
uprobes: Teach copy_insn() to support tmpfs
uprobes: Shift ->readpage check from __copy_insn() to uprobe_register()
perf/x86: Use common PMU interrupt disabled code
perf/ARM: Use common PMU interrupt disabled code
perf: Disable sampled events if no PMU interrupt
perf: Fix use after free in perf_remove_from_context()
perf tools: Fix 'make help' message error
perf record: Fix poll return value propagation
perf tools: Move elide bool into perf_hpp_fmt struct
perf tools: Remove elide setup for SORT_MODE__MEMORY mode
perf tools: Fix "==" into "=" in ui_browser__warning assignment
perf tools: Allow overriding sysfs and proc finding with env var
perf tools: Consider header files outside perf directory in tags target
...
06 May, 2014
1 commit
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Replace uses of &__get_cpu_var for address calculation with this_cpu_ptr.
Link: http://lkml.kernel.org/p/alpine.DEB.2.10.1404291415560.18364@gentwo.org
Acked-by: Masami Hiramatsu
Signed-off-by: Christoph Lameter
Signed-off-by: Steven Rostedt
24 Apr, 2014
2 commits
-
Introduce NOKPROBE_SYMBOL() macro which builds a kprobes
blacklist at kernel build time.The usage of this macro is similar to EXPORT_SYMBOL(),
placed after the function definition:NOKPROBE_SYMBOL(function);
Since this macro will inhibit inlining of static/inline
functions, this patch also introduces a nokprobe_inline macro
for static/inline functions. In this case, we must use
NOKPROBE_SYMBOL() for the inline function caller.When CONFIG_KPROBES=y, the macro stores the given function
address in the "_kprobe_blacklist" section.Since the data structures are not fully initialized by the
macro (because there is no "size" information), those
are re-initialized at boot time by using kallsyms.Signed-off-by: Masami Hiramatsu
Link: http://lkml.kernel.org/r/20140417081705.26341.96719.stgit@ltc230.yrl.intra.hitachi.co.jp
Cc: Alok Kataria
Cc: Ananth N Mavinakayanahalli
Cc: Andrew Morton
Cc: Anil S Keshavamurthy
Cc: Arnd Bergmann
Cc: Christopher Li
Cc: Chris Wright
Cc: David S. Miller
Cc: Jan-Simon Möller
Cc: Jeremy Fitzhardinge
Cc: Linus Torvalds
Cc: Randy Dunlap
Cc: Rusty Russell
Cc: linux-arch@vger.kernel.org
Cc: linux-doc@vger.kernel.org
Cc: linux-sparse@vger.kernel.org
Cc: virtualization@lists.linux-foundation.org
Signed-off-by: Ingo Molnar -
.entry.text is a code area which is used for interrupt/syscall
entries, which includes many sensitive code.
Thus, it is better to prohibit probing on all of such code
instead of a part of that.
Since some symbols are already registered on kprobe blacklist,
this also removes them from the blacklist.Signed-off-by: Masami Hiramatsu
Reviewed-by: Steven Rostedt
Cc: Ananth N Mavinakayanahalli
Cc: Anil S Keshavamurthy
Cc: Borislav Petkov
Cc: David S. Miller
Cc: Frederic Weisbecker
Cc: Jan Kiszka
Cc: Jiri Kosina
Cc: Jonathan Lebon
Cc: Seiji Aguchi
Link: http://lkml.kernel.org/r/20140417081658.26341.57354.stgit@ltc230.yrl.intra.hitachi.co.jp
Signed-off-by: Ingo Molnar
12 Sep, 2013
2 commits
-
The current two insn slot caches both use module_alloc/module_free to
allocate and free insn slot cache pages.For s390 this is not sufficient since there is the need to allocate insn
slots that are either within the vmalloc module area or within dma memory.Therefore add a mechanism which allows to specify an own allocator for an
own insn slot cache.Signed-off-by: Heiko Carstens
Acked-by: Masami Hiramatsu
Cc: Ananth N Mavinakayanahalli
Cc: Ingo Molnar
Cc: Martin Schwidefsky
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
The current kpropes insn caches allocate memory areas for insn slots
with module_alloc(). The assumption is that the kernel image and module
area are both within the same +/- 2GB memory area.This however is not true for s390 where the kernel image resides within
the first 2GB (DMA memory area), but the module area is far away in the
vmalloc area, usually somewhere close below the 4TB area.For new pc relative instructions s390 needs insn slots that are within
+/- 2GB of each area. That way we can patch displacements of
pc-relative instructions within the insn slots just like x86 and
powerpc.The module area works already with the normal insn slot allocator,
however there is currently no way to get insn slots that are within the
first 2GB on s390 (aka DMA area).Therefore this patch set modifies the kprobes insn slot cache code in
order to allow to specify a custom allocator for the insn slot cache
pages. In addition architecure can now have private insn slot caches
withhout the need to modify common code.Patch 1 unifies and simplifies the current insn and optinsn caches
implementation. This is a preparation which allows to add more
insn caches in a simple way.Patch 2 adds the possibility to specify a custom allocator.
Patch 3 makes s390 use the new insn slot mechanisms and adds support for
pc-relative instructions with long displacements.This patch (of 3):
The two insn caches (insn, and optinsn) each have an own mutex and
alloc/free functions (get_[opt]insn_slot() / free_[opt]insn_slot()).Since there is the need for yet another insn cache which satifies dma
allocations on s390, unify and simplify the current implementation:- Move the per insn cache mutex into struct kprobe_insn_cache.
- Move the alloc/free functions to kprobe.h so they are simply
wrappers for the generic __get_insn_slot/__free_insn_slot functions.
The implementation is done with a DEFINE_INSN_CACHE_OPS() macro
which provides the alloc/free functions for each cache if needed.
- move the struct kprobe_insn_cache to kprobe.h which allows to generate
architecture specific insn slot caches outside of the core kprobes
code.Signed-off-by: Heiko Carstens
Cc: Masami Hiramatsu
Cc: Ananth N Mavinakayanahalli
Cc: Ingo Molnar
Cc: Martin Schwidefsky
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
08 Apr, 2013
1 commit
-
Currently, __kprobes is defined in linux/kprobes.h which
is too big to be included in small or basic headers
that want to make use of this simple attribute.So move __kprobes definition into linux/compiler.h
in which other compiler attributes are defined.Signed-off-by: Masami Hiramatsu
Cc: Timo Juhani Lindfors
Cc: Ananth N Mavinakayanahalli
Cc: Pavel Emelyanov
Cc: Jiri Kosina
Cc: Nadia Yvette Chambers
Cc: yrl.pp-manager.tt@hitachi.com
Cc: David S. Miller
Cc: Linus Torvalds
Link: http://lkml.kernel.org/r/20130404104049.21071.20908.stgit@mhiramat-M0-7522
[ Improved the attribute explanation a bit. ]
Signed-off-by: Ingo Molnar
22 Jan, 2013
1 commit
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Split ftrace-based kprobes code from kprobes, and introduce
CONFIG_(HAVE_)KPROBES_ON_FTRACE Kconfig flags.
For the cleanup reason, this also moves kprobe_ftrace check
into skip_singlestep.Link: http://lkml.kernel.org/r/20120928081520.3560.25624.stgit@ltc138.sdl.hitachi.co.jp
Cc: Ingo Molnar
Cc: Ananth N Mavinakayanahalli
Cc: Peter Zijlstra
Cc: Thomas Gleixner
Cc: Ingo Molnar
Cc: "H. Peter Anvin"
Cc: Frederic Weisbecker
Signed-off-by: Masami Hiramatsu
Signed-off-by: Steven Rostedt
31 Jul, 2012
2 commits
-
Add function tracer based kprobe optimization support
handlers on x86. This allows kprobes to use function
tracer for probing on mcount call.Link: http://lkml.kernel.org/r/20120605102838.27845.26317.stgit@localhost.localdomain
Cc: Thomas Gleixner
Cc: Ingo Molnar
Cc: "H. Peter Anvin"
Cc: Ananth N Mavinakayanahalli
Cc: "Frank Ch. Eigler"
Cc: Andrew Morton
Cc: Frederic Weisbecker
Signed-off-by: Masami Hiramatsu[ Updated to new port of ftrace save regs functions ]
Signed-off-by: Steven Rostedt
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Introduce function trace based kprobes optimization.
With using ftrace optimization, kprobes on the mcount calling
address, use ftrace's mcount call instead of breakpoint.
Furthermore, this optimization works with preemptive kernel
not like as current jump-based optimization. Of cource,
this feature works only if the probe is on mcount call.Only if kprobe.break_handler is set, that probe is not
optimized with ftrace (nor put on ftrace). The reason why this
limitation comes is that this break_handler may be used only
from jprobes which changes ip address (for fetching the function
arguments), but function tracer ignores modified ip address.Changes in v2:
- Fix ftrace_ops registering right after setting its filter.
- Unregister ftrace_ops if there is no kprobe using.
- Remove notrace dependency from __kprobes macro.Link: http://lkml.kernel.org/r/20120605102832.27845.63461.stgit@localhost.localdomain
Cc: Thomas Gleixner
Cc: Ingo Molnar
Cc: "H. Peter Anvin"
Cc: Ananth N Mavinakayanahalli
Cc: "Frank Ch. Eigler"
Cc: Andrew Morton
Cc: Frederic Weisbecker
Signed-off-by: Masami Hiramatsu
Signed-off-by: Steven Rostedt
05 Mar, 2012
1 commit
-
If a header file is making use of BUG, BUG_ON, BUILD_BUG_ON, or any
other BUG variant in a static inline (i.e. not in a #define) then
that header really should be including and not just
expecting it to be implicitly present.We can make this change risk-free, since if the files using these
headers didn't have exposure to linux/bug.h already, they would have
been causing compile failures/warnings.Signed-off-by: Paul Gortmaker
13 Sep, 2011
1 commit
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The kprobe locks can be taken in atomic context and therefore
cannot be preempted on -rt - annotate it.In mainline this change documents the low level nature of
the lock - otherwise there's no functional difference. Lockdep
and Sparse checking will work as usual.Signed-off-by: Thomas Gleixner
Signed-off-by: Ingo Molnar
08 Jan, 2011
1 commit
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* 'for-2.6.38' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (30 commits)
gameport: use this_cpu_read instead of lookup
x86: udelay: Use this_cpu_read to avoid address calculation
x86: Use this_cpu_inc_return for nmi counter
x86: Replace uses of current_cpu_data with this_cpu ops
x86: Use this_cpu_ops to optimize code
vmstat: User per cpu atomics to avoid interrupt disable / enable
irq_work: Use per cpu atomics instead of regular atomics
cpuops: Use cmpxchg for xchg to avoid lock semantics
x86: this_cpu_cmpxchg and this_cpu_xchg operations
percpu: Generic this_cpu_cmpxchg() and this_cpu_xchg support
percpu,x86: relocate this_cpu_add_return() and friends
connector: Use this_cpu operations
xen: Use this_cpu_inc_return
taskstats: Use this_cpu_ops
random: Use this_cpu_inc_return
fs: Use this_cpu_inc_return in buffer.c
highmem: Use this_cpu_xx_return() operations
vmstat: Use this_cpu_inc_return for vm statistics
x86: Support for this_cpu_add, sub, dec, inc_return
percpu: Generic support for this_cpu_add, sub, dec, inc_return
...Fixed up conflicts: in arch/x86/kernel/{apic/nmi.c, apic/x2apic_uv_x.c, process.c}
as per Tejun.
17 Dec, 2010
1 commit
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Use this_cpu ops in various places to optimize per cpu data access.
Cc: Jason Baron
Cc: Namhyung Kim
Acked-by: H. Peter Anvin
Signed-off-by: Christoph Lameter
Signed-off-by: Tejun Heo
07 Dec, 2010
2 commits
-
Use text_poke_smp_batch() on unoptimization path for reducing
the number of stop_machine() issues. If the number of
unoptimizing probes is more than MAX_OPTIMIZE_PROBES(=256),
kprobes unoptimizes first MAX_OPTIMIZE_PROBES probes and kicks
optimizer for remaining probes.Signed-off-by: Masami Hiramatsu
Cc: Rusty Russell
Cc: Frederic Weisbecker
Cc: Ananth N Mavinakayanahalli
Cc: Jason Baron
Cc: Mathieu Desnoyers
Cc: 2nddept-manager@sdl.hitachi.co.jp
Cc: Peter Zijlstra
Cc: Steven Rostedt
LKML-Reference:
Signed-off-by: Ingo Molnar -
Use text_poke_smp_batch() in optimization path for reducing
the number of stop_machine() issues. If the number of optimizing
probes is more than MAX_OPTIMIZE_PROBES(=256), kprobes optimizes
first MAX_OPTIMIZE_PROBES probes and kicks optimizer for
remaining probes.Changes in v5:
- Use kick_kprobe_optimizer() instead of directly calling
schedule_delayed_work().
- Rescheduling optimizer outside of kprobe mutex lock.Changes in v2:
- Allocate code buffer and parameters in arch_init_kprobes()
instead of using static arraies.
- Merge previous max optimization limit patch into this patch.
So, this patch introduces upper limit of optimization at
once.Signed-off-by: Masami Hiramatsu
Cc: Rusty Russell
Cc: Frederic Weisbecker
Cc: Ananth N Mavinakayanahalli
Cc: Jason Baron
Cc: Mathieu Desnoyers
Cc: 2nddept-manager@sdl.hitachi.co.jp
Cc: Peter Zijlstra
Cc: Steven Rostedt
LKML-Reference:
Signed-off-by: Ingo Molnar