diff options
| author | Pawan Gupta <pawan.kumar.gupta@linux.intel.com> | 2022-03-10 14:02:09 -0800 |
|---|---|---|
| committer | Borislav Petkov <bp@suse.de> | 2022-04-11 09:58:40 +0200 |
| commit | 400331f8ffa3bec5c561417e5eec6848464e9160 (patch) | |
| tree | a13d7ac52030156c867f812614e3ccf75b5c6ea5 /arch/x86/kernel/cpu/intel.c | |
| parent | 258f3b8c3210b03386e4ad92b4bd8652b5c1beb3 (diff) | |
x86/tsx: Disable TSX development mode at boot
A microcode update on some Intel processors causes all TSX transactions
to always abort by default[*]. Microcode also added functionality to
re-enable TSX for development purposes. With this microcode loaded, if
tsx=on was passed on the cmdline, and TSX development mode was already
enabled before the kernel boot, it may make the system vulnerable to TSX
Asynchronous Abort (TAA).
To be on safer side, unconditionally disable TSX development mode during
boot. If a viable use case appears, this can be revisited later.
[*]: Intel TSX Disable Update for Selected Processors, doc ID: 643557
[ bp: Drop unstable web link, massage heavily. ]
Suggested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Suggested-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Tested-by: Neelima Krishnan <neelima.krishnan@intel.com>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/347bd844da3a333a9793c6687d4e4eb3b2419a3e.1646943780.git.pawan.kumar.gupta@linux.intel.com
Diffstat (limited to 'arch/x86/kernel/cpu/intel.c')
| -rw-r--r-- | arch/x86/kernel/cpu/intel.c | 8 |
1 files changed, 0 insertions, 8 deletions
diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c index 8abf995677a4..f7a5370a9b3b 100644 --- a/arch/x86/kernel/cpu/intel.c +++ b/arch/x86/kernel/cpu/intel.c @@ -717,14 +717,6 @@ static void init_intel(struct cpuinfo_x86 *c) init_intel_misc_features(c); - if (tsx_ctrl_state == TSX_CTRL_ENABLE) - tsx_enable(); - else if (tsx_ctrl_state == TSX_CTRL_DISABLE) - tsx_disable(); - else if (tsx_ctrl_state == TSX_CTRL_RTM_ALWAYS_ABORT) - /* See comment over that function for more details. */ - tsx_clear_cpuid(); - split_lock_init(); bus_lock_init(); |