From d4bfa64d44e0515c59e5274d2384dedd9f9d4cc8 Mon Sep 17 00:00:00 2001 From: Karel Zak Date: Tue, 13 Nov 2012 10:36:25 +0100 Subject: lscpu: make read_topology() more robust to avoid SIGFPE Signed-off-by: Karel Zak --- sys-utils/lscpu.c | 23 +++++++++++++++++------ 1 file changed, 17 insertions(+), 6 deletions(-) (limited to 'sys-utils/lscpu.c') diff --git a/sys-utils/lscpu.c b/sys-utils/lscpu.c index 5b1a0afee..a111561dc 100644 --- a/sys-utils/lscpu.c +++ b/sys-utils/lscpu.c @@ -627,16 +627,26 @@ read_topology(struct lscpu_desc *desc, int num) /* threads within one core */ nthreads = CPU_COUNT_S(setsize, thread_siblings); + if (!nthreads) + nthreads = 1; + /* cores within one socket */ ncores = CPU_COUNT_S(setsize, core_siblings) / nthreads; - /* number of sockets within one book. - * Because of odd / non-present cpu maps and to keep - * calculation easy we make sure that nsockets and - * nbooks is at least 1. + if (!ncores) + ncores = 1; + + /* number of sockets within one book. Because of odd / + * non-present cpu maps and to keep calculation easy we make + * sure that nsockets and nbooks is at least 1. */ - nsockets = desc->ncpus / nthreads / ncores ?: 1; + nsockets = desc->ncpus / nthreads / ncores; + if (!nsockets) + nsockets = 1; + /* number of books */ - nbooks = desc->ncpus / nthreads / ncores / nsockets ?: 1; + nbooks = desc->ncpus / nthreads / ncores / nsockets; + if (!nbooks) + nbooks = 1; /* all threads, see also read_basicinfo() * -- fallback for kernels without @@ -644,6 +654,7 @@ read_topology(struct lscpu_desc *desc, int num) */ if (!desc->nthreads) desc->nthreads = nbooks * nsockets * ncores * nthreads; + /* For each map we make sure that it can have up to ncpuspos * entries. This is because we cannot reliably calculate the * number of cores, sockets and books on all architectures. -- cgit v1.2.3-55-g7522