BMC/Intel-BMC/linux.git/arch/x86/kernel/kprobes, branch dev

Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2015-04-14T21:37:47+00:00

Pull perf changes from Ingo Molnar: "Core kernel changes: - One of the more interesting features in this cycle is the ability to attach eBPF programs (user-defined, sandboxed bytecode executed by the kernel) to kprobes. This allows user-defined instrumentation on a live kernel image that can never crash, hang or interfere with the kernel negatively. (Right now it's limited to root-only, but in the future we might allow unprivileged use as well.) (Alexei Starovoitov) - Another non-trivial feature is per event clockid support: this allows, amongst other things, the selection of different clock sources for event timestamps traced via perf. This feature is sought by people who'd like to merge perf generated events with external events that were measured with different clocks: - cluster wide profiling - for system wide tracing with user-space events, - JIT profiling events etc. Matching perf tooling support is added as well, available via the -k, --clockid parameter to perf record et al. (Peter Zijlstra) Hardware enablement kernel changes: - x86 Intel Processor Trace (PT) support: which is a hardware tracer on steroids, available on Broadwell CPUs. The hardware trace stream is directly output into the user-space ring-buffer, using the 'AUX' data format extension that was added to the perf core to support hardware constraints such as the necessity to have the tracing buffer physically contiguous. This patch-set was developed for two years and this is the result. A simple way to make use of this is to use BTS tracing, the PT driver emulates BTS output - available via the 'intel_bts' PMU. More explicit PT specific tooling support is in the works as well - will probably be ready by 4.2. (Alexander Shishkin, Peter Zijlstra) - x86 Intel Cache QoS Monitoring (CQM) support: this is a hardware feature of Intel Xeon CPUs that allows the measurement and allocation/partitioning of caches to individual workloads. These kernel changes expose the measurement side as a new PMU driver, which exposes various QoS related PMU events. (The partitioning change is work in progress and is planned to be merged as a cgroup extension.) (Matt Fleming, Peter Zijlstra; CPU feature detection by Peter P Waskiewicz Jr) - x86 Intel Haswell LBR call stack support: this is a new Haswell feature that allows the hardware recording of call chains, plus tooling support. To activate this feature you have to enable it via the new 'lbr' call-graph recording option: perf record --call-graph lbr perf report or: perf top --call-graph lbr This hardware feature is a lot faster than stack walk or dwarf based unwinding, but has some limitations: - It reuses the current LBR facility, so LBR call stack and branch record can not be enabled at the same time. - It is only available for user-space callchains. (Yan, Zheng) - x86 Intel Broadwell CPU support and various event constraints and event table fixes for earlier models. (Andi Kleen) - x86 Intel HT CPUs event scheduling workarounds. This is a complex CPU bug affecting the SNB,IVB,HSW families that results in counter value corruption. The mitigation code is automatically enabled and is transparent. (Maria Dimakopoulou, Stephane Eranian) The perf tooling side had a ton of changes in this cycle as well, so I'm only able to list the user visible changes here, in addition to the tooling changes outlined above: User visible changes affecting all tools: - Improve support of compressed kernel modules (Jiri Olsa) - Save DSO loading errno to better report errors (Arnaldo Carvalho de Melo) - Bash completion for subcommands (Yunlong Song) - Add 'I' event modifier for perf_event_attr.exclude_idle bit (Jiri Olsa) - Support missing -f to override perf.data file ownership. (Yunlong Song) - Show the first event with an invalid filter (David Ahern, Arnaldo Carvalho de Melo) User visible changes in individual tools: 'perf data': New tool for converting perf.data to other formats, initially for the CTF (Common Trace Format) from LTTng (Jiri Olsa, Sebastian Siewior) 'perf diff': Add --kallsyms option (David Ahern) 'perf list': Allow listing events with 'tracepoint' prefix (Yunlong Song) Sort the output of the command (Yunlong Song) 'perf kmem': Respect -i option (Jiri Olsa) Print big numbers using thousands' group (Namhyung Kim) Allow -v option (Namhyung Kim) Fix alignment of slab result table (Namhyung Kim) 'perf probe': Support multiple probes on different binaries on the same command line (Masami Hiramatsu) Support unnamed union/structure members data collection. (Masami Hiramatsu) Check kprobes blacklist when adding new events. (Masami Hiramatsu) 'perf record': Teach 'perf record' about perf_event_attr.clockid (Peter Zijlstra) Support recording running/enabled time (Andi Kleen) 'perf sched': Improve the performance of 'perf sched replay' on high CPU core count machines (Yunlong Song) 'perf report' and 'perf top': Allow annotating entries in callchains in the hists browser (Arnaldo Carvalho de Melo) Indicate which callchain entries are annotated in the TUI hists browser (Arnaldo Carvalho de Melo) Add pid/tid filtering to 'report' and 'script' commands (David Ahern) Consider PERF_RECORD_ events with cpumode == 0 in 'perf top', removing one cause of long term memory usage buildup, i.e. not processing PERF_RECORD_EXIT events (Arnaldo Carvalho de Melo) 'perf stat': Report unsupported events properly (Suzuki K. Poulose) Output running time and run/enabled ratio in CSV mode (Andi Kleen) 'perf trace': Handle legacy syscalls tracepoints (David Ahern, Arnaldo Carvalho de Melo) Only insert blank duration bracket when tracing syscalls (Arnaldo Carvalho de Melo) Filter out the trace pid when no threads are specified (Arnaldo Carvalho de Melo) Dump stack on segfaults (Arnaldo Carvalho de Melo) No need to explicitely enable evsels for workload started from perf, let it be enabled via perf_event_attr.enable_on_exec, removing some events that take place in the 'perf trace' before a workload is really started by it. (Arnaldo Carvalho de Melo) Allow mixing with tracepoints and suppressing plain syscalls. (Arnaldo Carvalho de Melo) There's also been a ton of infrastructure work done, such as the split-out of perf's build system into tools/build/ and other changes - see the shortlog and changelog for details" * 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (358 commits) perf/x86/intel/pt: Clean up the control flow in pt_pmu_hw_init() perf evlist: Fix type for references to data_head/tail perf probe: Check the orphaned -x option perf probe: Support multiple probes on different binaries perf buildid-list: Fix segfault when show DSOs with hits perf tools: Fix cross-endian analysis perf tools: Fix error path to do closedir() when synthesizing threads perf tools: Fix synthesizing fork_event.ppid for non-main thread perf tools: Add 'I' event modifier for exclude_idle bit perf report: Don't call map__kmap if map is NULL. perf tests: Fix attr tests perf probe: Fix ARM 32 building error perf tools: Merge all perf_event_attr print functions perf record: Add clockid parameter perf sched replay: Use replay_repeat to calculate the runavg of cpu usage instead of the default value 10 perf sched replay: Support using -f to override perf.data file ownership perf sched replay: Fix the EMFILE error caused by the limitation of the maximum open files perf sched replay: Handle the dead halt of sem_wait when create_tasks() fails for any task perf sched replay: Fix the segmentation fault problem caused by pr_err in threads perf sched replay: Realloc the memory of pid_to_task stepwise to adapt to the different pid_max configurations ...

x86/asm/entry: Change all 'user_mode_vm()' calls to 'user_mode()'

2015-03-23T10:14:17+00:00

user_mode_vm() and user_mode() are now the same. Change all callers of user_mode_vm() to user_mode(). The next patch will remove the definition of user_mode_vm. Signed-off-by: Andy Lutomirski Cc: Borislav Petkov Cc: Brad Spengler Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/43b1f57f3df70df5a08b0925897c660725015554.1426728647.git.luto@kernel.org [ Merged to a more recent kernel. ] Signed-off-by: Ingo Molnar

kprobes/x86: Return correct length in __copy_instruction()

2015-03-17T13:00:38+00:00

On x86-64, __copy_instruction() always returns 0 (error) if the instruction uses %rip-relative addressing. This is because kernel_insn_init() is called the second time for 'insn' instance in such cases and sets all its fields to 0. Because of this, trying to place a kprobe on such instruction will fail, register_kprobe() will return -EINVAL. This patch fixes the problem. Signed-off-by: Eugene Shatokhin Signed-off-by: Masami Hiramatsu Link: http://lkml.kernel.org/r/20150317100918.28349.94654.stgit@localhost.localdomain Signed-off-by: Ingo Molnar

Merge 'tip/perf/urgent' into perf/core to pick fixes

2015-03-02T14:45:49+00:00

Needed to build perf/core buildable in some cases. Signed-off-by: Arnaldo Carvalho de Melo

Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2015-03-01T19:56:13+00:00

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

Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2015-02-21T18:39:16+00:00

Pull x86 uprobe/kprobe fixes from Ingo Molnar: "This contains two uprobes fixes, an uprobes comment update and a kprobes fix" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: kprobes/x86: Mark 2 bytes NOP as boostable uprobes/x86: Fix 2-byte opcode table uprobes/x86: Fix 1-byte opcode tables uprobes/x86: Add comment with insn opcodes, mnemonics and why we dont support them

kprobes/x86: Check for invalid ftrace location in __recover_probed_insn()

2015-02-21T09:33:31+00:00

__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 Signed-off-by: Petr Mladek Cc: Ananth NMavinakayanahalli Cc: Anil S Keshavamurthy Cc: David S. Miller Cc: Frederic Weisbecker Cc: Jiri Kosina Cc: Steven Rostedt Link: http://lkml.kernel.org/r/1424441250-27146-3-git-send-email-pmladek@suse.cz Signed-off-by: Ingo Molnar

kprobes/x86: Use 5-byte NOP when the code might be modified by ftrace

2015-02-21T09:33:30+00:00

can_probe() checks if the given address points to the beginning of an instruction. It analyzes all the instructions from the beginning of the function until the given address. The code might be modified by another Kprobe. In this case, the current code is read into a buffer, int3 breakpoint is replaced by the saved opcode in the buffer, and can_probe() analyzes the buffer instead. There is a bug that __recover_probed_insn() tries to restore the original code even for Kprobes using the ftrace framework. But in this case, the opcode is not stored. See the difference between arch_prepare_kprobe() and arch_prepare_kprobe_ftrace(). The opcode is stored by arch_copy_kprobe() only from arch_prepare_kprobe(). This patch makes Kprobe to use the ideal 5-byte NOP when the code can be modified by ftrace. It is the original instruction, see ftrace_make_nop() and ftrace_nop_replace(). Note that we always need to use the NOP for ftrace locations. Kprobes do not block ftrace and the instruction might get modified at anytime. It might even be in an inconsistent state because it is modified step by step using the int3 breakpoint. The patch also fixes indentation of the touched comment. Note that I found this problem when playing with Kprobes. I did it on x86_64 with gcc-4.8.3 that supported -mfentry. I modified samples/kprobes/kprobe_example.c and added offset 5 to put the probe right after the fentry area: static struct kprobe kp = { .symbol_name = "do_fork", + .offset = 5, }; Then I was able to load kprobe_example before jprobe_example but not the other way around: $> modprobe jprobe_example $> modprobe kprobe_example modprobe: ERROR: could not insert 'kprobe_example': Invalid or incomplete multibyte or wide character It did not make much sense and debugging pointed to the bug described above. Signed-off-by: Petr Mladek Acked-by: Masami Hiramatsu Cc: Ananth NMavinakayanahalli Cc: Anil S Keshavamurthy Cc: David S. Miller Cc: Frederic Weisbecker Cc: Jiri Kosina Cc: Steven Rostedt Link: http://lkml.kernel.org/r/1424441250-27146-2-git-send-email-pmladek@suse.cz Signed-off-by: Ingo Molnar

kprobes/x86: Mark 2 bytes NOP as boostable

2015-02-18T20:50:12+00:00

Currently, x86 kprobes is unable to boost 2 bytes nop like: nopl 0x0(%rax,%rax,1) which is 0x0f 0x1f 0x44 0x00 0x00. Such nops have exactly 5 bytes to hold a relative jmp instruction. Boosting them should be obviously safe. This patch enable boosting such nops by simply updating twobyte_is_boostable[] array. Signed-off-by: Wang Nan Acked-by: Masami Hiramatsu Cc: Link: http://lkml.kernel.org/r/1423532045-41049-1-git-send-email-wangnan0@huawei.com Signed-off-by: Ingo Molnar

Merge branch 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm

2015-02-12T16:51:56+00:00

Pull ARM updates from Russell King: - clang assembly fixes from Ard - optimisations and cleanups for Aurora L2 cache support - efficient L2 cache support for secure monitor API on Exynos SoCs - debug menu cleanup from Daniel Thompson to allow better behaviour for multiplatform kernels - StrongARM SA11x0 conversion to irq domains, and pxa_timer - kprobes updates for older ARM CPUs - move probes support out of arch/arm/kernel to arch/arm/probes - add inline asm support for the rbit (reverse bits) instruction - provide an ARM mode secondary CPU entry point (for Qualcomm CPUs) - remove the unused ARMv3 user access code - add driver_override support to AMBA Primecell bus * 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm: (55 commits) ARM: 8256/1: driver coamba: add device binding path 'driver_override' ARM: 8301/1: qcom: Use secondary_startup_arm() ARM: 8302/1: Add a secondary_startup that assumes ARM mode ARM: 8300/1: teach __asmeq that r11 == fp and r12 == ip ARM: kprobes: Fix compilation error caused by superfluous '*' ARM: 8297/1: cache-l2x0: optimize aurora range operations ARM: 8296/1: cache-l2x0: clean up aurora cache handling ARM: 8284/1: sa1100: clear RCSR_SMR on resume ARM: 8283/1: sa1100: collie: clear PWER register on machine init ARM: 8282/1: sa1100: use handle_domain_irq ARM: 8281/1: sa1100: move GPIO-related IRQ code to gpio driver ARM: 8280/1: sa1100: switch to irq_domain_add_simple() ARM: 8279/1: sa1100: merge both GPIO irqdomains ARM: 8278/1: sa1100: split irq handling for low GPIOs ARM: 8291/1: replace magic number with PAGE_SHIFT macro in fixup_pv code ARM: 8290/1: decompressor: fix a wrong comment ARM: 8286/1: mm: Fix dma_contiguous_reserve comment ARM: 8248/1: pm: remove outdated comment ARM: 8274/1: Fix DEBUG_LL for multi-platform kernels (without PL01X) ARM: 8273/1: Seperate DEBUG_UART_PHYS from DEBUG_LL on EP93XX ...