43db2843a4
When build_cpu_topo() encounters offline/absent CPUs, it fails to find any sysfs entries and returns failure. This leads to build_cpu_topology() and write_cpu_topology() failing as well. Because HEADER_CPU_TOPOLOGY has not been written, read leaves cpu_topology_map NULL and we get NULL ptr deref at: ... cmd_test __cmd_test test_and_print run_test test_session_topology check_cpu_topology 36: Session topology : --- start --- test child forked, pid 14902 templ file: /tmp/perf-test-4CKocW failed to write feature HEADER_CPU_TOPOLOGY perf: Segmentation fault Obtained 9 stack frames. ./perf(sighandler_dump_stack+0x41) [0x5095f1] /lib64/libc.so.6(+0x35250) [0x7f4b7c3c9250] ./perf(test_session_topology+0x1db) [0x490ceb] ./perf() [0x475b68] ./perf(cmd_test+0x5b9) [0x4763c9] ./perf() [0x4945a3] ./perf(main+0x69f) [0x427e8f] /lib64/libc.so.6(__libc_start_main+0xf5) [0x7f4b7c3b5b35] ./perf() [0x427fb9] test child interrupted ---- end ---- Session topology: FAILED! This patch makes build_cpu_topology() skip offline/absent CPUs, by checking their presence against cpu_map built from online CPUs. Signed-off-by: Jan Stancek <jstancek@redhat.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/a271b770175524f4961d4903af33798358a4a518.1487146877.git.jstancek@redhat.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> |
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accounting | ||
arch | ||
build | ||
cgroup | ||
firewire | ||
gpio | ||
hv | ||
iio | ||
include | ||
kvm/kvm_stat | ||
laptop | ||
leds | ||
lguest | ||
lib | ||
net | ||
nfsd | ||
objtool | ||
pcmcia | ||
perf | ||
power | ||
scripts | ||
spi | ||
testing | ||
thermal/tmon | ||
time | ||
usb | ||
virtio | ||
vm | ||
Makefile |