4ab8455f8b
John reported crash when recording on an event under PMU with cpumask defined: root@localhost:~# ./perf_debug_ record -e armv8_pmuv3_0/br_mis_pred/ sleep 1 perf: Segmentation fault Obtained 9 stack frames. ./perf_debug_() [0x4c5ef8] [0xffff82ba267c] ./perf_debug_() [0x4bc5a8] ./perf_debug_() [0x419550] ./perf_debug_() [0x41a928] ./perf_debug_() [0x472f58] ./perf_debug_() [0x473210] ./perf_debug_() [0x4070f4] /lib/aarch64-linux-gnu/libc.so.6(__libc_start_main+0xe0) [0xffff8294c8a0] Segmentation fault (core dumped) We synthesize an update event that needs to touch the evsel id array, which is not defined at that time. Fixing this by forcing the id allocation for events with their own cpus. Reported-by: John Garry <john.garry@huawei.com> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Tested-by: John Garry <john.garry@huawei.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Will Deacon <will.deacon@arm.com> Cc: linux-arm-kernel@lists.infradead.org Cc: linuxarm@huawei.com Fixes: bfd8f72c2778 ("perf record: Synthesize unit/scale/... in event update") Link: http://lkml.kernel.org/r/20181003212052.GA32371@krava Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.