diff options
| author | Samuel Neves <sneves@dei.uc.pt> | 2018-02-21 20:50:36 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-05-30 07:49:01 +0200 |
| commit | 24cdc06fcf9dc32243a7e2693e3df3336ec5a7ef (patch) | |
| tree | 5c01c01162cb50638af4e3b41bc339067de228cf /arch | |
| parent | 9ee41dc649658bea9f6387c4e677025ec6ff5bdf (diff) | |
x86/topology: Update the 'cpu cores' field in /proc/cpuinfo correctly across CPU hotplug operations
[ Upstream commit 4596749339e06dc7a424fc08a15eded850ed78b7 ]
Without this fix, /proc/cpuinfo will display an incorrect amount
of CPU cores, after bringing them offline and online again, as
exemplified below:
$ cat /proc/cpuinfo | grep cores
cpu cores : 4
cpu cores : 8
cpu cores : 8
cpu cores : 20
cpu cores : 4
cpu cores : 3
cpu cores : 2
cpu cores : 2
This patch fixes this by always zeroing the booted_cores variable
upon turning off a logical CPU.
Tested-by: Dou Liyang <douly.fnst@cn.fujitsu.com>
Signed-off-by: Samuel Neves <sneves@dei.uc.pt>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: jgross@suse.com
Cc: luto@kernel.org
Cc: prarit@redhat.com
Cc: vkuznets@redhat.com
Link: http://lkml.kernel.org/r/20180221205036.5244-1-sneves@dei.uc.pt
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/kernel/smpboot.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c index 00c7878043ef..48ca93242bfd 100644 --- a/arch/x86/kernel/smpboot.c +++ b/arch/x86/kernel/smpboot.c @@ -1344,6 +1344,7 @@ static void remove_siblinginfo(int cpu) cpumask_clear(topology_core_cpumask(cpu)); c->phys_proc_id = 0; c->cpu_core_id = 0; + c->booted_cores = 0; cpumask_clear_cpu(cpu, cpu_sibling_setup_mask); } |