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* perf test: Add llvm-src-base.c and llvm-src-kbuild.c to .gitignoreYunlong Song2015-11-111-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | Commit b31de018a6284a25e0fdfeb028e724f8417ec3b1 ("perf test: Enhance the LLVM test: update basic BPF test program") dynamically creates file llvm-src-base.c during the perf building. Similarly, the commit 7af3f3d55b80cce40ad94b6b8e173dccedaf25e6 ("perf test: Enhance the LLVM tests: add kbuild test") dynamically creates file llvm-src-kbuild.c during the perf building. Add them to .gitignore. Signed-off-by: Yunlong Song <yunlong.song@huawei.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@intel.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Wang Nan <wangnan0@huawei.com> Fixes: b31de018a628 ("perf test: Enhance the LLVM test: update basic BPF test program") Fixes: 7af3f3d55b80 ("perf test: Enhance the LLVM tests: add kbuild test") Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf: Fix inherited events vs. tracepoint filtersPeter Zijlstra2015-11-091-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | Arnaldo reported that tracepoint filters seem to misbehave (ie. not apply) on inherited events. The fix is obvious; filters are only set on the actual (parent) event, use the normal pattern of using this parent event for filters. This is safe because each child event has a reference to it. Reported-by: Arnaldo Carvalho de Melo <acme@kernel.org> Tested-by: Arnaldo Carvalho de Melo <acme@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: David Ahern <dsahern@gmail.com> Cc: Frédéric Weisbecker <fweisbec@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Wang Nan <wangnan0@huawei.com> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/20151102095051.GN17308@twins.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
* perf: Disable IRQs across RCU RS CS that acquires scheduler lockPaul E. McKenney2015-11-091-8/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The perf_lock_task_context() function disables preemption across its RCU read-side critical section because that critical section acquires a scheduler lock. If there was a preemption during that RCU read-side critical section, the rcu_read_unlock() could attempt to acquire scheduler locks, resulting in deadlock. However, recent optimizations to expedited grace periods mean that IPI handlers that execute during preemptible RCU read-side critical sections can now cause the subsequent rcu_read_unlock() to acquire scheduler locks. Disabling preemption does nothiing to prevent these IPI handlers from executing, so these optimizations introduced a deadlock. In theory, this deadlock could be avoided by pulling all wakeups and printk()s out from rnp->lock critical sections, but in practice this would re-introduce some RCU CPU stall warning bugs. Given that acquiring scheduler locks entails disabling interrupts, these deadlocks can be avoided by disabling interrupts (instead of disabling preemption) across any RCU read-side critical that acquires scheduler locks and holds them across the rcu_read_unlock(). This commit therefore makes this change for perf_lock_task_context(). Reported-by: Dave Jones <davej@codemonkey.org.uk> Reported-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Stephane Eranian <eranian@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20151104134838.GR29027@linux.vnet.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* Merge tag 'perf-core-for-mingo-2' of ↵Ingo Molnar2015-11-0831-274/+920
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/urgent Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo: Fixes: - libbpf error reporting improvements, using a strerror interface to more precisely tell the user about problems with the provided scriptlet, be it in C or as a ready made object file (Wang Nan) - Do not be case sensitive when searching for matching 'perf test' entries (Arnaldo Carvalho de Melo) - Inform the user about objdump failures in 'perf annotate' (Andi Kleen) Infrastructure changes: - Improve the LLVM 'perf test' entry, introduce a new ones for BPF and kbuild tests to check the environment used by clang to compile .c scriptlets (Wang Nan) Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * perf test: Do not be case sensitive when searching for matching testsArnaldo Carvalho de Melo2015-11-061-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Before: # perf test llvm # perf test LLVM 35: Test LLVM searching and compiling : Ok # After # perf test llvm 35: Test LLVM searching and compiling : Ok # Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-c1u05npqbf6epse17ovfejoj@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| * perf test: Add 'perf test BPF'Wang Nan2015-11-066-1/+248
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds BPF testcase for testing BPF event filtering. By utilizing the result of 'perf test LLVM', this patch compiles the eBPF sample program then test its ability. The BPF script in 'perf test LLVM' lets only 50% samples generated by epoll_pwait() to be captured. This patch runs that system call for 111 times, so the result should contain 56 samples. Signed-off-by: Wang Nan <wangnan0@huawei.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1446817783-86722-8-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| * perf test: Enhance the LLVM tests: add kbuild testWang Nan2015-11-064-1/+35
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds a kbuild testcase to check whether kernel headers can be correctly found. For example: # mv /lib/modules/4.3.0-rc5{,.bak} # perf test LLVM 38: Test LLVM searching and compiling : Skip # perf test -v LLVM ... <stdin>:11:10: fatal error: 'uapi/linux/fs.h' file not found #include <uapi/linux/fs.h> ^ 1 error generated. ERROR: unable to compile - Hint: Check error message shown above. Hint: You can also pre-compile it into .o using: clang -target bpf -O2 -c - with proper -I and -D options. Failed to compile test case: 'Test kbuild searching' test child finished with -2 Signed-off-by: Wang Nan <wangnan0@huawei.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1446817783-86722-7-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| * perf test: Enhance the LLVM test: update basic BPF test programWang Nan2015-11-064-31/+129
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch replaces the original toy BPF program with the previously introduced bpf-script-example.c. Dynamically embeddeding it into 'llvm-src-base.c'. The newly introduced BPF program attaches a BPF program to 'sys_epoll_pwait()'. perf itself never use that syscall, so further test can verify their result with it. The program would generate 1 sample in every 2 calls of epoll_pwait() system call. Since the resulting BPF object is useful per se for further tests, test_llvm__fetch_bpf_obj() is introduced for creating BPF objects from source. The LLVM test was rewritten to use it. Committer note: Running it: [root@zoo wb]# perf test -v LLVM 35: Test LLVM searching and compiling : --- start --- test child forked, pid 17740 Kernel build dir is set to /lib/modules/4.3.0-rc1+/build set env: KBUILD_DIR=/lib/modules/4.3.0-rc1+/build unset env: KBUILD_OPTS include option is set to -nostdinc -isystem /usr/lib/gcc/x86_64-redhat-linux/4.9.2/include -I/home/git/linux/arch/x86/include -Iarch/x86/include/generated/uapi -Iarch/x86/include/generated -I/home/git/linux/include -Iinclude -I/home/git/linux/arch/x86/include/uapi -Iarch/x86/include/generated/uapi -I/home/git/linux/include/uapi -Iinclude/generated/uapi -include /home/git/linux/include/linux/kconfig.h set env: NR_CPUS=4 set env: LINUX_VERSION_CODE=0x40300 set env: CLANG_EXEC=/usr/libexec/icecc/bin/clang set env: CLANG_OPTIONS=-xc set env: KERNEL_INC_OPTIONS= -nostdinc -isystem /usr/lib/gcc/x86_64-redhat-linux/4.9.2/include -I/home/git/linux/arch/x86/include -Iarch/x86/include/generated/uapi -Iarch/x86/include/generated -I/home/git/linux/include -Iinclude -I/home/git/linux/arch/x86/include/uapi -Iarch/x86/include/generated/uapi -I/home/git/linux/include/uapi -Iinclude/generated/uapi -include /home/git/linux/include/linux/kconfig.h set env: WORKING_DIR=/lib/modules/4.3.0-rc1+/build set env: CLANG_SOURCE=- llvm compiling command template: echo '/* * bpf-script-example.c * Test basic LLVM building */ #ifndef LINUX_VERSION_CODE # error Need LINUX_VERSION_CODE # error Example: for 4.2 kernel, put 'clang-opt="-DLINUX_VERSION_CODE=0x40200" into llvm section of ~/.perfconfig' #endif #define BPF_ANY 0 #define BPF_MAP_TYPE_ARRAY 2 #define BPF_FUNC_map_lookup_elem 1 #define BPF_FUNC_map_update_elem 2 static void *(*bpf_map_lookup_elem)(void *map, void *key) = (void *) BPF_FUNC_map_lookup_elem; static void *(*bpf_map_update_elem)(void *map, void *key, void *value, int flags) = (void *) BPF_FUNC_map_update_elem; struct bpf_map_def { unsigned int type; unsigned int key_size; unsigned int value_size; unsigned int max_entries; }; #define SEC(NAME) __attribute__((section(NAME), used)) struct bpf_map_def SEC("maps") flip_table = { .type = BPF_MAP_TYPE_ARRAY, .key_size = sizeof(int), .value_size = sizeof(int), .max_entries = 1, }; SEC("func=sys_epoll_pwait") int bpf_func__sys_epoll_pwait(void *ctx) { int ind =0; int *flag = bpf_map_lookup_elem(&flip_table, &ind); int new_flag; if (!flag) return 0; /* flip flag and store back */ new_flag = !*flag; bpf_map_update_elem(&flip_table, &ind, &new_flag, BPF_ANY); return new_flag; } char _license[] SEC("license") = "GPL"; int _version SEC("version") = LINUX_VERSION_CODE; ' | $CLANG_EXEC -D__KERNEL__ -D__NR_CPUS__=$NR_CPUS -DLINUX_VERSION_CODE=$LINUX_VERSION_CODE $CLANG_OPTIONS $KERNEL_INC_OPTIONS -Wno-unused-value -Wno-pointer-sign -working-directory $WORKING_DIR -c "$CLANG_SOURCE" -target bpf -O2 -o - test child finished with 0 ---- end ---- Test LLVM searching and compiling: Ok [root@zoo wb]# Signed-off-by: Wang Nan <wangnan0@huawei.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1446817783-86722-6-git-send-email-wangnan0@huawei.com Signed-off-by: He Kuang <hekuang@huawei.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| * perf bpf: Improve BPF related error messagesWang Nan2015-11-064-15/+108
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A series of bpf loader related error codes were introduced to help error reporting. Functions were improved to return these new error codes. Functions which return pointers were adjusted to encode error codes into return value using the ERR_PTR() interface. bpf_loader_strerror() was improved to convert these error messages to strings. It checks the error codes and calls libbpf_strerror() and strerror_r() accordingly, so caller don't need to consider checking the range of the error code. In bpf__strerror_load(), print kernel version of running kernel and the object's 'version' section to notify user how to fix his/her program. v1 -> v2: Use macro for error code. Fetch error message based on array index, eliminate for-loop. Print version strings. Before: # perf record -e ./test_kversion_nomatch_program.o sleep 1 event syntax error: './test_kversion_nomatch_program.o' \___ Failed to load program: Validate your program and check 'license'/'version' sections in your object SKIP After: # perf record -e ./test_kversion_nomatch_program.o ls event syntax error: './test_kversion_nomatch_program.o' \___ 'version' (4.4.0) doesn't match running kernel (4.3.0) SKIP Signed-off-by: Wang Nan <wangnan0@huawei.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1446818289-87444-1-git-send-email-wangnan0@huawei.com [ Add 'static inline' to bpf__strerror_prepare_load() when LIBBPF is disabled ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| * perf tools: Make fetch_kernel_version() publicly availableWang Nan2015-11-063-33/+49
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There are 2 places in llvm-utils.c which find kernel version information through uname. This patch extracts the uname related code into a fetch_kernel_version() function and puts it into util.h so it can be reused. Signed-off-by: Wang Nan <wangnan0@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1446818135-87310-1-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| * bpf tools: Add new API bpf_object__get_kversion()Wang Nan2015-11-062-0/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | bpf_object__get_kversion() can be used to fetch value of object's 'version' section. Following patch will use it for error reporting. Signed-off-by: Wang Nan <wangnan0@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1446817783-86722-3-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| * bpf tools: Improve libbpf error reportingWang Nan2015-11-065-59/+159
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In this patch, a series of libbpf specific error numbers and libbpf_strerror() are introduced to help reporting errors. Functions are updated to pass correct the error number through the CHECK_ERR() macro. All users of bpf_object__open{_buffer}() and bpf_program__title() in perf are modified accordingly. In addition, due to the error codes changing, bpf__strerror_load() is also modified to use them. bpf__strerror_head() is also changed accordingly so it can parse libbpf errors. bpf_loader_strerror() is introduced for that purpose, and will be improved by the following patch. load_program() is improved not to dump log buffer if it is empty. log buffer is also used to deduce whether the error was caused by an invalid program or other problem. v1 -> v2: - Using macro for error code. - Fetch error message based on array index, eliminate for-loop. - Use log buffer to detect the reason of failure. 3 new error code are introduced to replace LIBBPF_ERRNO__LOAD. In v1: # perf record -e ./test_ill_program.o ls event syntax error: './test_ill_program.o' \___ Failed to load program: Validate your program and check 'license'/'version' sections in your object SKIP # perf record -e ./test_kversion_nomatch_program.o ls event syntax error: './test_kversion_nomatch_program.o' \___ Failed to load program: Validate your program and check 'license'/'version' sections in your object SKIP # perf record -e ./test_big_program.o ls event syntax error: './test_big_program.o' \___ Failed to load program: Validate your program and check 'license'/'version' sections in your object SKIP In v2: # perf record -e ./test_ill_program.o ls event syntax error: './test_ill_program.o' \___ Kernel verifier blocks program loading SKIP # perf record -e ./test_kversion_nomatch_program.o event syntax error: './test_kversion_nomatch_program.o' \___ Incorrect kernel version SKIP (Will be further improved by following patches) # perf record -e ./test_big_program.o event syntax error: './test_big_program.o' \___ Program too big SKIP Signed-off-by: Wang Nan <wangnan0@huawei.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1446817783-86722-2-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| * perf probe: Cleanup find_perf_probe_point_from_map to reduce redundancyMasami Hiramatsu2015-11-061-5/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In find_perf_probe_point_from_map(), the 'ret' variable is initialized with -ENOENT but overwritten by the return code of kernel_get_symbol_address_by_name(), and after that it is re-initialized with -ENOENT again. Setting ret=-ENOENT twice looks a bit redundant. This avoids the overwriting and just returns -ENOENT if some error happens to simplify the code. Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Cc: Zefan Li <lizefan@huawei.com> Link: http://lkml.kernel.org/n/tip-ufp1zgbktzmttcputozneomd@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| * perf annotate: Inform the user about objdump failures in --stdioAndi Kleen2015-11-061-2/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When the browser fails to annotate it is difficult for users to find out what went wrong. Add some errors for objdump failures that are displayed in the UI. Note it would be even better to handle these errors smarter, like falling back to the binary when the debug info is somehow corrupted. But for now just giving a better error is an improvement. Committer note: This works for --stdio, where errors just scroll by the screen: # perf annotate --stdio intel_idle Failure running objdump --start-address=0xffffffff81418290 --stop-address=0xffffffff814183ae -l -d --no-show-raw -S -C /root/.debug/.build-id/28/2777c262e6b3c0451375163c9a81c893218ab1 2>/dev/null|grep -v /root/.debug/.build-id/28/2777c262e6b3c0451375163c9a81c893218ab1|expand Percent | Source code & Disassembly of vmlinux for cycles:pp ------------------------------------------------------------------ And with that one can use that command line to try to find out more about what happened instead of getting a blank screen, an improvement. We need tho to improve this further to get it to work with other UIs, like --tui and --gtk, where it continues showing a blank screen, no messages, as the pr_err() used is enough just for --stdio. Signed-off-by: Andi Kleen <ak@linux.intel.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Link: http://lkml.kernel.org/r/1446779167-18949-1-git-send-email-andi@firstfloor.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| * perf stat: Make stat options globalJiri Olsa2015-11-051-81/+82
| | | | | | | | | | | | | | | | | | | | | | | | So they can be used in perf stat record command in following patch. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Tested-by: Kan Liang <kan.liang@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1446734469-11352-2-git-send-email-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| * perf sched latency: Fix thread pid reuse issueJiri Olsa2015-11-051-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The latency subcommand holds a tree of working atoms sorted by thread's pid/tid. If there's new thread with same pid and tid, the old working atom is found and assert bug condition is hit in search function: thread_atoms_search: Assertion `!(thread != atoms->thread)' failed Changing the sort function to use thread object pointers together with pid and tid check. This way new thread will never find old one with same pid/tid. Link: http://lkml.kernel.org/n/tip-o4doazhhv0zax5zshkg8hnys@git.kernel.org Reported-by: Mohit Agrawal <moagrawa@redhat.com> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Acked-by: Namhyung Kim <namhyung@kernel.org> Cc: David Ahern <dsahern@gmail.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1446462625-15807-1-git-send-email-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| * perf tools: Fix find_perf_probe_point_from_map() which incorrectly returns ↵Wang Nan2015-11-051-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | success It is possible that find_perf_probe_point_from_map() fails to find a symbol but still returns 0 because of an small error when coding: find_perf_probe_point_from_map() set 'ret' to error code at first, but also use it to hold return value of kernel_get_symbol_address_by_name(). This patch resets 'ret' to error even kernel_get_symbol_address_by_name() success, so if !sym, the whole function returns error correctly. Signed-off-by: Wang Nan <wangnan0@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1446729565-27592-3-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| * perf trace: Fix documentation for -iPeter Feiner2015-11-051-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The -i flag was incorrectly listed as a short flag for --no-inherit. It should have only been listed as a short flag for --input. This documentation error has existed since the --input flag was introduced in 6810fc915f7a89d8134edb3996dbbf8eac386c26 (perf trace: Add option to analyze events in a file versus live). Signed-off-by: Peter Feiner <pfeiner@google.com> Cc: David Ahern <dsahern@gmail.com> Link: http://lkml.kernel.org/r/1446657706-14518-1-git-send-email-pfeiner@google.com Fixes: 6810fc915f7a ("perf trace: Add option to analyze events in a file versus live") Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| * tools lib bpf: Change FEATURE-DUMP to FEATURE-DUMP.libbpfYunlong Song2015-11-052-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit ed63f34c026e9a60d17fa750ecdfe3f600d49393 ("perf tools: Make perf depend on libbpf") triggers the build of libbpf when building the perf tools, dynamically creating FEATURE-DUMP.libbpf. It failed to update the tools/lib/bpf/.gitignore file to have that prefix, fix it. Signed-off-by: Yunlong Song <yunlong.song@huawei.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@intel.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Wang Nan <wangnan0@huawei.com> Fixes: 65f041bee783 ("tools lib bpf: Use FEATURE_USER to allow building in the same dir as perf") Link: http://lkml.kernel.org/r/1446706594-4142-1-git-send-email-yunlong.song@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| * perf llvm: Pass LINUX_VERSION_CODE to BPF program when compilingWang Nan2015-11-051-0/+27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Arnaldo suggests to make LINUX_VERSION_CODE works like __func__ and __FILE__ so user don't need to care setting right linux version too much. In this patch, perf llvm transfers LINUX_VERSION_CODE macro through clang cmdline. [1] http://lkml.kernel.org/r/20151029223744.GK2923@kernel.org Committer notes: Before, forgetting to update the version: # uname -r 4.3.0-rc1+ # cat bpf.c __attribute__((section("fork=_do_fork"), used)) int fork(void *ctx) { return 1; } char _license[] __attribute__((section("license"), used)) = "GPL"; int _version __attribute__((section("version"), used)) = 0x40200; # # perf record -e bpf.c sleep 1 event syntax error: 'bpf.c' \___ Invalid argument: Are you root and runing a CONFIG_BPF_SYSCALL kernel? (add -v to see detail) Run 'perf list' for a list of valid events Usage: perf record [<options>] [<command>] or: perf record [<options>] -- <command> [<options>] -e, --event <event> event selector. use 'perf list' to list available events # After: # grep version bpf.c int _version __attribute__((section("version"), used)) = LINUX_VERSION_CODE; # perf record -e bpf.c sleep 1 [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.017 MB perf.data ] # perf evlist -v perf_bpf_probe:fork: type: 2, size: 112, config: 0x5ee, { sample_period, sample_freq }: 1, sample_type: IP|TID|TIME|CPU|PERIOD|RAW, disabled: 1, inherit: 1, mmap: 1, comm: 1, enable_on_exec: 1, task: 1, sample_id_all: 1, exclude_guest: 1, mmap2: 1, comm_exec: 1 # Suggested-and-Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Wang Nan <wangnan0@huawei.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1446636007-239722-3-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| * perf llvm: Pass number of configured CPUs to clang compilerWang Nan2015-11-051-6/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch introduces a new macro "__NR_CPUS__" to perf's embedded clang compiler, which represent the number of configured CPUs in this system. BPF programs can use this macro to create a map with the same number of system CPUs. For example: struct bpf_map_def SEC("maps") pmu_map = { .type = BPF_MAP_TYPE_PERF_EVENT_ARRAY, .key_size = sizeof(int), .value_size = sizeof(u32), .max_entries = __NR_CPUS__, }; Signed-off-by: Wang Nan <wangnan0@huawei.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1446636007-239722-2-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| * perf tools: Allow shuffling the build testsArnaldo Carvalho de Melo2015-11-052-1/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Those tests take a long time and sometimes we stop it, so allow randomly shuffling the tests so that we have a better chance of running more of them in partial 'make build-test' runs. Using it just on the 'build-test' target, i.e.: make -C tools/perf build-test Is equivalent to: make SHUF=1 -C tools/perf -f tests/make Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-ey7461i9q4k8u0987j8guun6@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| * perf tools: Insert split maps correctly into origin groupJiri Olsa2015-11-051-2/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When new maps are cloned out of split map they are added into origin map's group, but their groups pointer is not updated. This could lead to a segfault, because map->groups is expected to be always set as reported by Markus: __map__is_kernel (map=map@entry=0x1abb7a0) at util/map.c:238 238 return __machine__kernel_map(map->groups->machine, map->type) = (gdb) bt #0 __map__is_kernel (map=map@entry=0x1abb7a0) at util/map.c:238 #1 0x00000000004393e4 in symbol_filter (map=map@entry=0x1abb7a0, sym=sym@entry #2 0x00000000004fcd4d in dso__load_sym (dso=dso@entry=0x166dae0, map=map@entry #3 0x00000000004a64e0 in dso__load (dso=0x166dae0, map=map@entry=0x1abb7a0, fi #4 0x00000000004b941f in map__load (filter=0x4393c0 <symbol_filter>, map=<opti #5 map__find_symbol (map=0x1abb7a0, addr=40188, filter=0x4393c0 <symbol_filter ... Adding __map_groups__insert function to add map into groups together with map->groups pointer update. It takes no lock as opposed to existing map_groups__insert, as maps__fixup_overlappings(), where it is being called, already has the necessary lock held. Using __map_groups__insert to add new maps after map split. Reported-by: Markus Trippelsdorf <markus@trippelsdorf.de> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Tested-by: Markus Trippelsdorf <markus@trippelsdorf.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20151104140811.GA32664@krava.brq.redhat.com Fixes: cfc5acd4c80b ("perf top: Filter symbols based on __map__is_kernel(map)") Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| * perf stat: Use common printout function to avoid duplicated codeAndi Kleen2015-11-041-37/+20
| | | | | | | | | | | | | | | | | | | | Instead of every caller deciding whether to call abs or nsec printout do it all in a single central function. No functional changes. Signed-off-by: Andi Kleen <ak@linux.intel.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Link: http://lkml.kernel.org/r/1446515428-7450-3-git-send-email-andi@firstfloor.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| * perf stat: Move sw clock metrics printout to stat-shadowAndi Kleen2015-11-042-5/+8
| | | | | | | | | | | | | | | | | | | | | | | | The sw clock metrics printing was missed in the earlier move to stat-shadow of all the other metric printouts. Move it too. v2: Fix metrics printing in this version to make bisect safe. Signed-off-by: Andi Kleen <ak@linux.intel.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Link: http://lkml.kernel.org/r/1446515428-7450-2-git-send-email-andi@firstfloor.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| * tools lib bpf: Fix compiler warning on CentOS 6Namhyung Kim2015-11-032-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | CC libbpf.o cc1: warnings being treated as errors libbpf.c: In function 'bpf_program__title': libbpf.c:1037: error: declaration of 'dup' shadows a global declaration /usr/include/unistd.h:528: error: shadowed declaration is here mv: cannot stat `./.libbpf.o.tmp': No such file or directory make[3]: *** [libbpf.o] Error 1 make[2]: *** [libbpf-in.o] Error 2 make[1]: *** [/linux/tools/lib/bpf/libbpf.a] Error 2 make[1]: *** Waiting for unfinished jobs.... Signed-off-by: Namhyung Kim <namhyung@kernel.org> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/r/1446549665-2342-1-git-send-email-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| * perf bpf: Mute libbpf when '-v' not setWang Nan2015-11-031-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | According to [1], libbpf should be muted. This patch reset info and warning message level to ensure libbpf doesn't output anything even if error happened. [1] http://lkml.kernel.org/r/20151020151255.GF5119@kernel.org Committer note: Before: Testing it with an incompatible kernel version in the .c file that generated foo.o: [root@zoo ~]# perf record -e /tmp/foo.o sleep 1 libbpf: load bpf program failed: Invalid argument libbpf: -- BEGIN DUMP LOG --- libbpf: libbpf: -- END LOG -- libbpf: failed to load program 'fork=_do_fork' libbpf: failed to load object '/tmp/foo.o' event syntax error: '/tmp/foo.o' \___ Invalid argument: Are you root and runing a CONFIG_BPF_SYSCALL kernel? (add -v to see detail) Run 'perf list' for a list of valid events Usage: perf record [<options>] [<command>] or: perf record [<options>] -- <command> [<options>] -e, --event <event> event selector. use 'perf list' to list available events [root@zoo ~]# After: [root@zoo ~]# perf record -e /tmp/foo.o sleep 1 event syntax error: '/tmp/foo.o' \___ Invalid argument: Are you root and runing a CONFIG_BPF_SYSCALL kernel? (add -v to see detail) Run 'perf list' for a list of valid events Usage: perf record [<options>] [<command>] or: perf record [<options>] -- <command> [<options>] -e, --event <event> event selector. use 'perf list' to list available events [root@zoo ~]# This, BTW, need fixing to emit a proper message by validating the version in the foo.o "version" ELF section against the running kernel, warning the user instead of asking the kernel to load a binary that it will refuse due to unmatching kernel version. Signed-off-by: Wang Nan <wangnan0@huawei.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1446547486-229499-3-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| * perf test: Keep test result clean if '-v' not setWang Nan2015-11-035-17/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | According to [1], 'perf test' should avoid output too much information if '-v' is not set, only 'Ok', 'FAIL' or 'Skip' need to be printed. This patch removes several messages sent directly to stderr to make the output clean. Before this patch: # perf test dummy 23: Test using a dummy software event to keep tracking : (not supported) Ok After this patch: # perf test dummy 23: Test using a dummy software event to keep tracking : Skip [1] http://lkml.kernel.org/r/20151020134155.GE4400@redhat.com Signed-off-by: Wang Nan <wangnan0@huawei.com> Acked-by: Namhyung Kim <namhyung@kernel.org> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1446547486-229499-2-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* | Merge branch 'x86-platform-for-linus' of ↵Linus Torvalds2015-11-034-27/+33
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 platform changes from Ingo Molnar: "Misc updates to the Intel MID and SGI UV platforms" * 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/intel-mid: Make intel_mid_ops static arch/x86/intel-mid: Use kmemdup rather than duplicating its implementation x86/platform/uv: Implement simple dump failover if kdump fails x86/platform/uv: Insert per_cpu accessor function on uv_hub_nmi
| * | x86/intel-mid: Make intel_mid_ops staticAndy Shevchenko2015-10-111-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The following warning is issued on unfixed code. arch/x86/platform/intel-mid/intel-mid.c:64:22: warning: symbol 'intel_mid_ops' was not declared. Should it be static? Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: http://lkml.kernel.org/r/1444400741-98669-1-git-send-email-andriy.shevchenko@linux.intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | arch/x86/intel-mid: Use kmemdup rather than duplicating its implementationAndrzej Hajda2015-09-171-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The patch was generated using fixed coccinelle semantic patch scripts/coccinelle/api/memdup.cocci [1]. [1]: http://permalink.gmane.org/gmane.linux.kernel/2014320 Signed-off-by: Andrzej Hajda <a.hajda@samsung.com> Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Julia Lawall <Julia.Lawall@lip6.fr> Link: http://lkml.kernel.org/r/1438934377-4922-9-git-send-email-a.hajda@samsung.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | x86/platform/uv: Implement simple dump failover if kdump failsMike Travis2015-09-141-23/+30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The ability to trigger a kdump using the system NMI command was added by commit 12ba6c990fab ("x86/UV: Add kdump to UV NMI handler") Author: Mike Travis <travis@sgi.com> Date: Mon Sep 23 16:25:03 2013 -0500 This is useful because when kdump is working the information gathered is more informative than the original per CPU stack traces or "dump" option. However a number of things can go wrong with kdump and then the stack traces are more useful than nothing. The two most common reasons for kdump to not be available are: 1) if a problem occurs during boot before the kdump service is started, or 2) the kdump daemon failed to start. In either case the call to crash_kexec() returns unexpectedly. When this happens uv_nmi_kdump() also sets the uv_nmi_kexec_failed flag which causes the slave CPU's to also return to the NMI handler. Upon this unexpected return to the NMI handler, the NMI handler will revert to the "dump" action which uses show_regs() to obtain a process trace dump for all the CPU's. Other minor changes: The "dump" action now generates both the show_regs() stack trace and show instruction pointer information. Whereas the "ips" action only shows instruction pointers for non-idle CPU's. This is more like an abbreviated "ps" display. Change printk(KERN_DEFAULT...) --> pr_info() Signed-off-by: Mike Travis <travis@sgi.com> Signed-off-by: George Beshers <gbeshers@sgi.com> Cc: Alex Thorlton <athorlton@sgi.com> Cc: Dimitri Sivanich <sivanich@sgi.com> Cc: Hedi Berriche <hedi@sgi.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Russ Anderson <rja@sgi.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | x86/platform/uv: Insert per_cpu accessor function on uv_hub_nmiGeorge Beshers2015-09-131-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | UV: NMI: insert this_cpu_read accessor function on uv_hub_nmi. On SGI UV systems a 'power nmi' command from the CMC causes all processors to drop into uv_handle_nmi(). With the 4.0 kernel this results in BUG: unable to handle kernel paging request The bug is caused by the current code trying to use the PER_CPU variable uv_cpu_nmi.hub without an appropriate accessor function. That oversight occurred in commit e16321709c82 ("uv: Replace __get_cpu_var") Author: Christoph Lameter <cl@linux.com> Date: Sun Aug 17 12:30:41 2014 -0500 This patch inserts this_cpu_read() in the uv_hub_nmi macro restoring the intended functionality. Signed-off-by: George Beshers <gbeshers@sgi.com> Acked-by: Mike Travis <travis@sgi.com> Cc: Alex Thorlton <athorlton@sgi.com> Cc: Dimitri Sivanich <sivanich@sgi.com> Cc: Hedi Berriche <hedi@sgi.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Russ Anderson <rja@sgi.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | | Merge branch 'x86-mm-for-linus' of ↵Linus Torvalds2015-11-0312-74/+219
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 mm changes from Ingo Molnar: "The main changes are: continued PAT work by Toshi Kani, plus a new boot time warning about insecure RWX kernel mappings, by Stephen Smalley. The new CONFIG_DEBUG_WX=y warning is marked default-y if CONFIG_DEBUG_RODATA=y is already eanbled, as a special exception, as these bugs are hard to notice and this check already found several live bugs" * 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mm: Warn on W^X mappings x86/mm: Fix no-change case in try_preserve_large_page() x86/mm: Fix __split_large_page() to handle large PAT bit x86/mm: Fix try_preserve_large_page() to handle large PAT bit x86/mm: Fix gup_huge_p?d() to handle large PAT bit x86/mm: Fix slow_virt_to_phys() to handle large PAT bit x86/mm: Fix page table dump to show PAT bit x86/asm: Add pud_pgprot() and pmd_pgprot() x86/asm: Fix pud/pmd interfaces to handle large PAT bit x86/asm: Add pud/pmd mask interfaces to handle large PAT bit x86/asm: Move PUD_PAGE macros to page_types.h x86/vdso32: Define PGTABLE_LEVELS to 32bit VDSO
| * | | x86/mm: Warn on W^X mappingsStephen Smalley2015-10-066-3/+88
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Warn on any residual W+X mappings after setting NX if DEBUG_WX is enabled. Introduce a separate X86_PTDUMP_CORE config that enables the code for dumping the page tables without enabling the debugfs interface, so that DEBUG_WX can be enabled without exposing the debugfs interface. Switch EFI_PGT_DUMP to using X86_PTDUMP_CORE so that it also does not require enabling the debugfs interface. On success it prints this to the kernel log: x86/mm: Checked W+X mappings: passed, no W+X pages found. On failure it prints a warning and a count of the failed pages: ------------[ cut here ]------------ WARNING: CPU: 1 PID: 1 at arch/x86/mm/dump_pagetables.c:226 note_page+0x610/0x7b0() x86/mm: Found insecure W+X mapping at address ffffffff81755000/__stop___ex_table+0xfa8/0xabfa8 [...] Call Trace: [<ffffffff81380a5f>] dump_stack+0x44/0x55 [<ffffffff8109d3f2>] warn_slowpath_common+0x82/0xc0 [<ffffffff8109d48c>] warn_slowpath_fmt+0x5c/0x80 [<ffffffff8106cfc9>] ? note_page+0x5c9/0x7b0 [<ffffffff8106d010>] note_page+0x610/0x7b0 [<ffffffff8106d409>] ptdump_walk_pgd_level_core+0x259/0x3c0 [<ffffffff8106d5a7>] ptdump_walk_pgd_level_checkwx+0x17/0x20 [<ffffffff81063905>] mark_rodata_ro+0xf5/0x100 [<ffffffff817415a0>] ? rest_init+0x80/0x80 [<ffffffff817415bd>] kernel_init+0x1d/0xe0 [<ffffffff8174cd1f>] ret_from_fork+0x3f/0x70 [<ffffffff817415a0>] ? rest_init+0x80/0x80 ---[ end trace a1f23a1e42a2ac76 ]--- x86/mm: Checked W+X mappings: FAILED, 171 W+X pages found. Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Acked-by: Kees Cook <keescook@chromium.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Link: http://lkml.kernel.org/r/1444064120-11450-1-git-send-email-sds@tycho.nsa.gov [ Improved the Kconfig help text and made the new option default-y if CONFIG_DEBUG_RODATA=y, because it already found buggy mappings, so we really want people to have this on by default. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | Merge tag 'v4.3-rc3' into x86/mm, to pick up fixes before applying new changesIngo Molnar2015-10-06436-2581/+4983
| |\ \ \ | | | | | | | | | | | | | | | Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | x86/mm: Fix no-change case in try_preserve_large_page()Toshi Kani2015-09-221-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | try_preserve_large_page() checks if new_prot is the same as old_prot. If so, it simply sets do_split to 0, and returns with no-operation. However, old_prot is set as a 4KB pgprot value while new_prot is a large page pgprot value. Now that old_prot is initially set from p?d_pgprot() as a large page pgprot value, fix it by not overwriting old_prot with a 4KB pgprot value. Signed-off-by: Toshi Kani <toshi.kani@hpe.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Juergen Gross <jgross@suse.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Konrad Wilk <konrad.wilk@oracle.com> Cc: Robert Elliot <elliott@hpe.com> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/1442514264-12475-12-git-send-email-toshi.kani@hpe.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | | x86/mm: Fix __split_large_page() to handle large PAT bitToshi Kani2015-09-221-12/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | __split_large_page() is called from __change_page_attr() to change the mapping attribute by splitting a given large page into smaller pages. This function uses pte_pfn() and pte_pgprot() for PUD/PMD, which do not handle the large PAT bit properly. Fix __split_large_page() by using the corresponding pud/pmd pfn/ pgprot interfaces. Also remove '#ifdef CONFIG_X86_64', which is not necessary. Signed-off-by: Toshi Kani <toshi.kani@hpe.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Juergen Gross <jgross@suse.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Konrad Wilk <konrad.wilk@oracle.com> Cc: Robert Elliot <elliott@hpe.com> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/1442514264-12475-11-git-send-email-toshi.kani@hpe.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | | x86/mm: Fix try_preserve_large_page() to handle large PAT bitToshi Kani2015-09-221-10/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | try_preserve_large_page() is called from __change_page_attr() to change the mapping attribute of a given large page. This function uses pte_pfn() and pte_pgprot() for PUD/PMD, which do not handle the large PAT bit properly. Fix try_preserve_large_page() by using the corresponding pud/pmd prot/pfn interfaces. Also remove '#ifdef CONFIG_X86_64', which is not necessary. Signed-off-by: Toshi Kani <toshi.kani@hpe.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Juergen Gross <jgross@suse.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Konrad Wilk <konrad.wilk@oracle.com> Cc: Robert Elliot <elliott@hpe.com> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/1442514264-12475-10-git-send-email-toshi.kani@hpe.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | | x86/mm: Fix gup_huge_p?d() to handle large PAT bitToshi Kani2015-09-221-10/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | gup_huge_pud() and gup_huge_pmd() cast *pud and *pmd to *pte, and use pte_xxx() interfaces to obtain the flags and PFN. However, the pte_xxx() interface does not handle the large PAT bit properly for PUD/PMD. Fix gup_huge_pud() and gup_huge_pmd() to use pud_xxx() and pmd_xxx() interfaces according to their type. Signed-off-by: Toshi Kani <toshi.kani@hpe.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Juergen Gross <jgross@suse.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Konrad Wilk <konrad.wilk@oracle.com> Cc: Robert Elliot <elliott@hpe.com> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/1442514264-12475-9-git-send-email-toshi.kani@hpe.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | | x86/mm: Fix slow_virt_to_phys() to handle large PAT bitToshi Kani2015-09-221-7/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | slow_virt_to_phys() calls lookup_address() to obtain *pte and its level. It then calls pte_pfn() to obtain a physical address for any level. However, this physical address is not correct when the large PAT bit is set because pte_pfn() does not mask the large PAT bit properly for PUD/PMD. Fix slow_virt_to_phys() to use pud_pfn() and pmd_pfn() for 1GB and 2MB mapping levels. Signed-off-by: Toshi Kani <toshi.kani@hpe.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Juergen Gross <jgross@suse.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Konrad Wilk <konrad.wilk@oracle.com> Cc: Robert Elliot <elliott@hpe.com> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/1442514264-12475-8-git-send-email-toshi.kani@hpe.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | | x86/mm: Fix page table dump to show PAT bitToshi Kani2015-09-221-18/+21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | /sys/kernel/debug/kernel_page_tables does not show the PAT bit for PUD/PMD mappings. This is because walk_pud_level(), walk_pmd_level() and note_page() mask the flags with PTE_FLAGS_MASK, which does not cover their PAT bit, _PAGE_PAT_LARGE. Fix it by replacing the use of PTE_FLAGS_MASK with p?d_flags(), which masks the flags properly. Also change to show the PAT bit as "PAT" to be consistent with other bits. Reported-by: Robert Elliott <elliott@hpe.com> Signed-off-by: Toshi Kani <toshi.kani@hpe.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Juergen Gross <jgross@suse.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Konrad Wilk <konrad.wilk@oracle.com> Cc: Robert Elliot <elliott@hpe.com> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/1442514264-12475-7-git-send-email-toshi.kani@hpe.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | | x86/asm: Add pud_pgprot() and pmd_pgprot()Toshi Kani2015-09-221-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | pte_pgprot() returns a pgprot_t value by calling pte_flags(). Now that pud_flags() and pmd_flags() work specifically for the pud/pmd levels, define pud_pgprot() and pmd_pgprot() for PUD/PMD. Also update pte_pgprot() to remove the unnecessary mask with PTE_FLAGS_MASK as pte_flags() takes care of it. Signed-off-by: Toshi Kani <toshi.kani@hpe.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Juergen Gross <jgross@suse.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Konrad Wilk <konrad.wilk@oracle.com> Cc: Robert Elliot <elliott@hpe.com> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/1442514264-12475-6-git-send-email-toshi.kani@hpe.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | | x86/asm: Fix pud/pmd interfaces to handle large PAT bitToshi Kani2015-09-222-8/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Now that we have pud/pmd mask interfaces, which handle pfn & flags mask properly for the large PAT bit. Fix pud/pmd pfn & flags interfaces by replacing PTE_PFN_MASK and PTE_FLAGS_MASK with the pud/pmd mask interfaces. Suggested-by: Juergen Gross <jgross@suse.com> Signed-off-by: Toshi Kani <toshi.kani@hpe.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Juergen Gross <jgross@suse.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Konrad Wilk <konrad.wilk@oracle.com> Cc: Robert Elliot <elliott@hpe.com> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/1442514264-12475-5-git-send-email-toshi.kani@hpe.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | | x86/asm: Add pud/pmd mask interfaces to handle large PAT bitToshi Kani2015-09-221-2/+34
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The PAT bit gets relocated to bit 12 when PUD and PMD mappings are used. This bit 12, however, is not covered by PTE_FLAGS_MASK, which is used for masking pfn and flags for all levels. Add pud/pmd mask interfaces to handle pfn and flags properly by using P?D_PAGE_MASK when PUD/PMD mappings are used, i.e. PSE bit is set. Suggested-by: Juergen Gross <jgross@suse.com> Signed-off-by: Toshi Kani <toshi.kani@hpe.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Juergen Gross <jgross@suse.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Konrad Wilk <konrad.wilk@oracle.com> Cc: Robert Elliot <elliott@hpe.com> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/1442514264-12475-4-git-send-email-toshi.kani@hpe.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | | x86/asm: Move PUD_PAGE macros to page_types.hToshi Kani2015-09-222-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | PUD_SHIFT is defined according to a given kernel configuration, which allows it be commonly used by any x86 kernels. However, PUD_PAGE_SIZE and PUD_PAGE_MASK, which are set from PUD_SHIFT, are defined in page_64_types.h, which can be used by 64-bit kernel only. Move PUD_PAGE_SIZE and PUD_PAGE_MASK to page_types.h so that they can be used by any x86 kernels as well. Signed-off-by: Toshi Kani <toshi.kani@hpe.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Juergen Gross <jgross@suse.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Konrad Wilk <konrad.wilk@oracle.com> Cc: Robert Elliot <elliott@hpe.com> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/1442514264-12475-3-git-send-email-toshi.kani@hpe.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | | x86/vdso32: Define PGTABLE_LEVELS to 32bit VDSOToshi Kani2015-09-221-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In case of CONFIG_X86_64, vdso32/vclock_gettime.c fakes a 32-bit non-PAE kernel configuration by re-defining it to CONFIG_X86_32. However, it does not re-define CONFIG_PGTABLE_LEVELS leaving it as 4 levels. This mismatch leads <asm/pgtable_type.h> to NOT include <asm-generic/ pgtable-nopud.h> and <asm-generic/pgtable-nopmd.h>, which will cause compile errors when a later patch enhances <asm/pgtable_type.h> to use PUD_SHIFT and PMD_SHIFT. These -nopud & -nopmd headers define these SHIFTs for the 32-bit non-PAE kernel. Fix it by re-defining CONFIG_PGTABLE_LEVELS to 2 levels. Signed-off-by: Toshi Kani <toshi.kani@hpe.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Juergen Gross <jgross@suse.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Konrad Wilk <konrad.wilk@oracle.com> Cc: Robert Elliot <elliott@hpe.com> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/1442514264-12475-2-git-send-email-toshi.kani@hpe.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* | | | | Merge branch 'x86-headers-for-linus' of ↵Linus Torvalds2015-11-0313-339/+338
|\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 sigcontext header cleanups from Ingo Molnar: "This series reorganizes and cleans up various aspects of the main sigcontext UAPI headers, such as unifying the data structures and updating/adding lots of comments to explain all the ABI details and quirks. The headers can now also be built in user-space standalone" * 'x86-headers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/headers: Clean up too long lines x86/headers: Remove <asm/sigcontext.h> references on the kernel side x86/headers: Remove direct sigcontext32.h uses x86/headers: Convert sigcontext_ia32 uses to sigcontext_32 x86/headers: Unify 'struct sigcontext_ia32' and 'struct sigcontext_32' x86/headers: Make sigcontext pointers bit independent x86/headers: Move the 'struct sigcontext' definitions into the UAPI header x86/headers: Clean up the kernel's struct sigcontext types to be ABI-clean x86/headers: Convert uses of _fpstate_ia32 to _fpstate_32 x86/headers: Unify 'struct _fpstate_ia32' and i386 struct _fpstate x86/headers: Unify register type definitions between 32-bit compat and i386 x86/headers: Use ABI types consistently in sigcontext*.h x86/headers: Separate out legacy user-space structure definitions x86/headers: Clean up and better document uapi/asm/sigcontext.h x86/headers: Clean up uapi/asm/sigcontext32.h x86/headers: Fix (old) header file dependency bug in uapi/asm/sigcontext32.h
| * | | | | x86/headers: Clean up too long linesPeter Zijlstra2015-09-141-26/+31
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: bp@alien8.de Cc: brgerst@gmail.com Cc: dvlasenk@redhat.com Cc: luto@amacapital.net Cc: mikko.rapeli@iki.fi Cc: oleg@redhat.com Link: http://lkml.kernel.org/r/20150909071244.GM3644@twins.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | x86/headers: Remove <asm/sigcontext.h> references on the kernel sideIngo Molnar2015-09-088-7/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Now that all type definitions are in the UAPI header, include it directly, instead of through <asm/sigcontext.h>. [ We still keep asm/sigcontext.h, so that uapi/asm/sigcontext32.h can include <asm/sigcontext.h>. ] Acked-by: Mikko Rapeli <mikko.rapeli@iki.fi> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Link: http://lkml.kernel.org/r/1441438363-9999-16-git-send-email-mingo@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>