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| author | Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> | 2019-04-13 00:50:58 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-05-14 20:19:41 +0300 |
| commit | 3645b361be489077bd85458c40e47be791ca318c (patch) | |
| tree | 44c02ef93ebb9219fce21f94eb0e25488359b0c5 /arch | |
| parent | 450aa01a076d9aa5b459a7a33c74d95eca6a1e37 (diff) | |
| download | linux-3645b361be489077bd85458c40e47be791ca318c.tar.xz | |
x86/speculation/mds: Print SMT vulnerable on MSBDS with mitigations off
commit e2c3c94788b08891dcf3dbe608f9880523ecd71b upstream.
This code is only for CPUs which are affected by MSBDS, but are *not*
affected by the other two MDS issues.
For such CPUs, enabling the mds_idle_clear mitigation is enough to
mitigate SMT.
However if user boots with 'mds=off' and still has SMT enabled, we should
not report that SMT is mitigated:
$cat /sys//devices/system/cpu/vulnerabilities/mds
Vulnerable; SMT mitigated
But rather:
Vulnerable; SMT vulnerable
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Tyler Hicks <tyhicks@canonical.com>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/20190412215118.294906495@localhost.localdomain
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/kernel/cpu/bugs.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c index b32fb55d94e1..d81f55e4ca5c 100644 --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -1196,7 +1196,8 @@ static ssize_t mds_show_state(char *buf) if (boot_cpu_has(X86_BUG_MSBDS_ONLY)) { return sprintf(buf, "%s; SMT %s\n", mds_strings[mds_mitigation], - sched_smt_active() ? "mitigated" : "disabled"); + (mds_mitigation == MDS_MITIGATION_OFF ? "vulnerable" : + sched_smt_active() ? "mitigated" : "disabled")); } return sprintf(buf, "%s; SMT %s\n", mds_strings[mds_mitigation], |