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2015-03-01Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fixes from Ingo Molnar: "Two kprobes fixes and a handful of tooling fixes" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf tools: Make sparc64 arch point to sparc perf symbols: Define EM_AARCH64 for older OSes perf top: Fix SIGBUS on sparc64 perf tools: Fix probing for PERF_FLAG_FD_CLOEXEC flag perf tools: Fix pthread_attr_setaffinity_np build error perf tools: Define _GNU_SOURCE on pthread_attr_setaffinity_np feature check perf bench: Fix order of arguments to memcpy_alloc_mem kprobes/x86: Check for invalid ftrace location in __recover_probed_insn() kprobes/x86: Use 5-byte NOP when the code might be modified by ftrace
2015-02-21kprobes/x86: Check for invalid ftrace location in __recover_probed_insn()Petr Mladek
__recover_probed_insn() should always be called from an address where an instructions starts. The check for ftrace_location() might help to discover a potential inconsistency. This patch adds WARN_ON() when the inconsistency is detected. Also it adds handling of the situation when the original code can not get recovered. Suggested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Petr Mladek <pmladek@suse.cz> Cc: Ananth NMavinakayanahalli <ananth@in.ibm.com> Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> Cc: David S. Miller <davem@davemloft.net> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/1424441250-27146-3-git-send-email-pmladek@suse.cz Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-01-13kprobes: Pass the original kprobe for preparing optimized kprobeMasami Hiramatsu
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 <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Wang Nan <wangnan0@huawei.com> Signed-off-by: Jon Medhurst <tixy@linaro.org>
2014-11-18x86: Remove arbitrary instruction size limit in instruction decoderDave Hansen
The current x86 instruction decoder steps along through the instruction stream but always ensures that it never steps farther than the largest possible instruction size (MAX_INSN_SIZE). The MPX code is now going to be doing some decoding of userspace instructions. We copy those from userspace in to the kernel and they're obviously completely untrusted coming from userspace. In addition to the constraint that instructions can only be so long, we also have to be aware of how long the buffer is that came in from userspace. This _looks_ to be similar to what the perf and kprobes is doing, but it's unclear to me whether they are affected. The whole reason we need this is that it is perfectly valid to be executing an instruction within MAX_INSN_SIZE bytes of an unreadable page. We should be able to gracefully handle short reads in those cases. This adds support to the decoder to record how long the buffer being decoded is and to refuse to "validate" the instruction if we would have gone over the end of the buffer to decode it. The kprobes code probably needs to be looked at here a bit more carefully. This patch still respects the MAX_INSN_SIZE limit there but the kprobes code does look like it might be able to be a bit more strict than it currently is. Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: Jim Keniston <jkenisto@us.ibm.com> Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: x86@kernel.org Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> Cc: "David S. Miller" <davem@davemloft.net> Link: http://lkml.kernel.org/r/20141114153957.E6B01535@viggo.jf.intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-08-27kprobes/x86: Free 'optinsn' cache when range check failsWang Nan
This patch frees the 'optinsn' slot when we get a range check error, to prevent memory leaks. Before this patch, cache entry in kprobe_insn_cache() won't be freed if kprobe optimizing fails due to range check failure. Signed-off-by: Wang Nan <wangnan0@huawei.com> Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Pei Feiyue <peifeiyue@huawei.com> Link: http://lkml.kernel.org/r/1406550019-70935-1-git-send-email-wangnan0@huawei.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-04-24kprobes, x86: Use NOKPROBE_SYMBOL() instead of __kprobes annotationMasami Hiramatsu
Use NOKPROBE_SYMBOL macro for protecting functions from kprobes instead of __kprobes annotation under arch/x86. This applies nokprobe_inline annotation for some cases, because NOKPROBE_SYMBOL() will inhibit inlining by referring the symbol address. This just folds a bunch of previous NOKPROBE_SYMBOL() cleanup patches for x86 to one patch. Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Link: http://lkml.kernel.org/r/20140417081814.26341.51656.stgit@ltc230.yrl.intra.hitachi.co.jp Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Borislav Petkov <bp@suse.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fernando Luis Vázquez Cao <fernando_b1@lab.ntt.co.jp> Cc: Gleb Natapov <gleb@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Jesper Nilsson <jesper.nilsson@axis.com> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Jonathan Lebon <jlebon@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Matt Fleming <matt.fleming@intel.com> Cc: Michel Lespinasse <walken@google.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Seiji Aguchi <seiji.aguchi@hds.com> Cc: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com> Cc: Tejun Heo <tj@kernel.org> Cc: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-04-24kprobes/x86: Allow probe on some kprobe preparation functionsMasami Hiramatsu
There is no need to prohibit probing on the functions used in preparation phase. Those are safely probed because those are not invoked from breakpoint/fault/debug handlers, there is no chance to cause recursive exceptions. Following functions are now removed from the kprobes blacklist: can_boost can_probe can_optimize is_IF_modifier __copy_instruction copy_optimized_instructions arch_copy_kprobe arch_prepare_kprobe arch_arm_kprobe arch_disarm_kprobe arch_remove_kprobe arch_trampoline_kprobe arch_prepare_kprobe_ftrace arch_prepare_optimized_kprobe arch_check_optimized_kprobe arch_within_optimized_kprobe __arch_remove_optimized_kprobe arch_remove_optimized_kprobe arch_optimize_kprobes arch_unoptimize_kprobe I tested those functions by putting kprobes on all instructions in the functions with the bash script I sent to LKML. See: https://lkml.org/lkml/2014/3/27/33 Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Jonathan Lebon <jlebon@redhat.com> Link: http://lkml.kernel.org/r/20140417081747.26341.36065.stgit@ltc230.yrl.intra.hitachi.co.jp Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-09-04Merge branch 'x86-asmlinkage-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86/asmlinkage changes from Ingo Molnar: "As a preparation for Andi Kleen's LTO patchset (link time optimizations using GCC's -flto which build time optimization has steadily increased in quality over the past few years and might eventually be usable for the kernel too) this tree includes a handful of preparatory patches that make function calling convention annotations consistent again: - Mark every function without arguments (or 64bit only) that is used by assembly code with asmlinkage() - Mark every function with parameters or variables that is used by assembly code as __visible. For the vanilla kernel this has documentation, consistency and debuggability advantages, for the time being" * 'x86-asmlinkage-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/asmlinkage: Fix warning in xen asmlinkage change x86, asmlinkage, vdso: Mark vdso variables __visible x86, asmlinkage, power: Make various symbols used by the suspend asm code visible x86, asmlinkage: Make dump_stack visible x86, asmlinkage: Make 64bit checksum functions visible x86, asmlinkage, paravirt: Add __visible/asmlinkage to xen paravirt ops x86, asmlinkage, apm: Make APM data structure used from assembler visible x86, asmlinkage: Make syscall tables visible x86, asmlinkage: Make several variables used from assembler/linker script visible x86, asmlinkage: Make kprobes code visible and fix assembler code x86, asmlinkage: Make various syscalls asmlinkage x86, asmlinkage: Make 32bit/64bit __switch_to visible x86, asmlinkage: Make _*_start_kernel visible x86, asmlinkage: Make all interrupt handlers asmlinkage / __visible x86, asmlinkage: Change dotraplinkage into __visible on 32bit x86: Fix sys_call_table type in asm/syscall.h
2013-08-06x86, asmlinkage: Make kprobes code visible and fix assembler codeAndi Kleen
- Make all the external assembler template symbols __visible - Move the templates inline assembler code into a top level assembler statement, not inside a function. This avoids it being optimized away or cloned. Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Andi Kleen <ak@linux.intel.com> Link: http://lkml.kernel.org/r/1375740170-7446-8-git-send-email-andi@firstfloor.org Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-07-19kprobes/x86: Use text_poke_bp() instead of text_poke_smp*()Masami Hiramatsu
Use text_poke_bp() for optimizing kprobes instead of text_poke_smp*(). Since the number of kprobes is usually not so large (<100) and text_poke_bp() is much lighter than text_poke_smp() [which uses stop_machine()], this just stops using batch processing. Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Reviewed-by: Jiri Kosina <jkosina@suse.cz> Cc: H. Peter Anvin <hpa@linux.intel.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Jason Baron <jbaron@akamai.com> Cc: yrl.pp-manager.tt@hitachi.com Cc: Borislav Petkov <bpetkov@suse.de> Link: http://lkml.kernel.org/r/20130718114750.26675.9174.stgit@mhiramat-M0-7522 Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-07-19kprobes/x86: Remove an incorrect comment about int3 in NMI/MCEMasami Hiramatsu
Remove a comment about an int3 issue in NMI/MCE, since commit: 3f3c8b8c4b2a ("x86: Add workaround to NMI iret woes") already fixed that. Keeping this incorrect comment can mislead developers. Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Reviewed-by: Jiri Kosina <jkosina@suse.cz> Cc: H. Peter Anvin <hpa@linux.intel.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Jason Baron <jbaron@akamai.com> Cc: yrl.pp-manager.tt@hitachi.com Cc: Borislav Petkov <bpetkov@suse.de> Link: http://lkml.kernel.org/r/20130718114747.26675.84110.stgit@mhiramat-M0-7522 Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-01-21kprobes/x86: Move kprobes stuff under arch/x86/kernel/kprobes/Masami Hiramatsu
Move arch-dep kprobes stuff under arch/x86/kernel/kprobes. Link: http://lkml.kernel.org/r/20120928081522.3560.75469.stgit@ltc138.sdl.hitachi.co.jp Cc: Ingo Molnar <mingo@elte.hu> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> [ fixed whitespace and s/__attribute__((packed))/__packed/ ] Signed-off-by: Steven Rostedt <rostedt@goodmis.org>