diff options
| author | Josh Poimboeuf <jpoimboe@redhat.com> | 2018-07-24 18:17:40 +0200 |
|---|---|---|
| committer | Peter Zijlstra <peterz@infradead.org> | 2018-07-24 18:17:40 +0200 |
| commit | 73d5e2b472640b1fcdb61ae8be389912ef211bda (patch) | |
| tree | a0b859dfb525e4a89dc068194177108d5745f46d /ipc/mq_sysctl.c | |
| parent | 1949f9f49792d65dba2090edddbe36a5f02e3ba3 (diff) | |
cpu/hotplug: detect SMT disabled by BIOS
If SMT is disabled in BIOS, the CPU code doesn't properly detect it.
The /sys/devices/system/cpu/smt/control file shows 'on', and the 'l1tf'
vulnerabilities file shows SMT as vulnerable.
Fix it by forcing 'cpu_smt_control' to CPU_SMT_NOT_SUPPORTED in such a
case. Unfortunately the detection can only be done after bringing all
the CPUs online, so we have to overwrite any previous writes to the
variable.
Reported-by: Joe Mario <jmario@redhat.com>
Tested-by: Jiri Kosina <jkosina@suse.cz>
Fixes: f048c399e0f7 ("x86/topology: Provide topology_smt_supported()")
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Diffstat (limited to 'ipc/mq_sysctl.c')
0 files changed, 0 insertions, 0 deletions