From: Alexander Gordeev agordeev@linux.ibm.com
[ Upstream commit 872f27103874a73783aeff2aac2b41a489f67d7c ]
/proc/cpuinfo should not print information about CPU 0 when it is offline.
Fixes: 281eaa8cb67c ("s390/cpuinfo: simplify locking and skip offline cpus early") Signed-off-by: Alexander Gordeev agordeev@linux.ibm.com Reviewed-by: Heiko Carstens heiko.carstens@de.ibm.com [heiko.carstens@de.ibm.com: shortened commit message] Signed-off-by: Heiko Carstens heiko.carstens@de.ibm.com Signed-off-by: Vasily Gorbik gor@linux.ibm.com Signed-off-by: Sasha Levin sashal@kernel.org --- arch/s390/kernel/processor.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/arch/s390/kernel/processor.c b/arch/s390/kernel/processor.c index 6fe2e1875058b..675d4be0c2b77 100644 --- a/arch/s390/kernel/processor.c +++ b/arch/s390/kernel/processor.c @@ -157,8 +157,9 @@ static void show_cpu_mhz(struct seq_file *m, unsigned long n) static int show_cpuinfo(struct seq_file *m, void *v) { unsigned long n = (unsigned long) v - 1; + unsigned long first = cpumask_first(cpu_online_mask);
- if (!n) + if (n == first) show_cpu_summary(m, v); if (!machine_has_cpu_mhz) return 0; @@ -171,6 +172,8 @@ static inline void *c_update(loff_t *pos) { if (*pos) *pos = cpumask_next(*pos - 1, cpu_online_mask); + else + *pos = cpumask_first(cpu_online_mask); return *pos < nr_cpu_ids ? (void *)*pos + 1 : NULL; }