diff options
| author | Josh Poimboeuf <jpoimboe@kernel.org> | 2022-06-14 23:16:07 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-07-25 11:26:46 +0200 |
| commit | aad83db22e9950577b5b827f57ed7108b3ca5553 (patch) | |
| tree | 935570cb5715ef144118a0569f058518bb52fc5d | |
| parent | d29c07912a49fce965228f73a293e2c899bc7e35 (diff) | |
| download | linux-aad83db22e9950577b5b827f57ed7108b3ca5553.tar.gz linux-aad83db22e9950577b5b827f57ed7108b3ca5553.tar.bz2 linux-aad83db22e9950577b5b827f57ed7108b3ca5553.zip | |
x86/speculation: Fix SPEC_CTRL write on SMT state change
commit 56aa4d221f1ee2c3a49b45b800778ec6e0ab73c5 upstream.
If the SMT state changes, SSBD might get accidentally disabled. Fix
that.
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -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 8205834dd11e..33af6f9ab241 100644 --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -1414,7 +1414,8 @@ static void __init spectre_v2_select_mitigation(void) static void update_stibp_msr(void * __unused) { - write_spec_ctrl_current(x86_spec_ctrl_base, true); + u64 val = spec_ctrl_current() | (x86_spec_ctrl_base & SPEC_CTRL_STIBP); + write_spec_ctrl_current(val, true); } /* Update x86_spec_ctrl_base in case SMT state changed. */ |