diff options
Diffstat (limited to 'arch/x86/kernel/cpu/tsx.c')
| -rw-r--r-- | arch/x86/kernel/cpu/tsx.c | 37 |
1 files changed, 35 insertions, 2 deletions
diff --git a/arch/x86/kernel/cpu/tsx.c b/arch/x86/kernel/cpu/tsx.c index e2ad30e474f8..9c7a5f049292 100644 --- a/arch/x86/kernel/cpu/tsx.c +++ b/arch/x86/kernel/cpu/tsx.c @@ -2,7 +2,7 @@ /* * Intel Transactional Synchronization Extensions (TSX) control. * - * Copyright (C) 2019 Intel Corporation + * Copyright (C) 2019-2021 Intel Corporation * * Author: * Pawan Gupta <pawan.kumar.gupta@linux.intel.com> @@ -84,13 +84,46 @@ static enum tsx_ctrl_states x86_get_tsx_auto_mode(void) return TSX_CTRL_ENABLE; } +void tsx_clear_cpuid(void) +{ + u64 msr; + + /* + * MSR_TFA_TSX_CPUID_CLEAR bit is only present when both CPUID + * bits RTM_ALWAYS_ABORT and TSX_FORCE_ABORT are present. + */ + if (boot_cpu_has(X86_FEATURE_RTM_ALWAYS_ABORT) && + boot_cpu_has(X86_FEATURE_TSX_FORCE_ABORT)) { + rdmsrl(MSR_TSX_FORCE_ABORT, msr); + msr |= MSR_TFA_TSX_CPUID_CLEAR; + wrmsrl(MSR_TSX_FORCE_ABORT, msr); + } +} + void __init tsx_init(void) { char arg[5] = {}; int ret; - if (!tsx_ctrl_is_supported()) + /* + * Hardware will always abort a TSX transaction if both CPUID bits + * RTM_ALWAYS_ABORT and TSX_FORCE_ABORT are set. In this case, it is + * better not to enumerate CPUID.RTM and CPUID.HLE bits. Clear them + * here. + */ + if (boot_cpu_has(X86_FEATURE_RTM_ALWAYS_ABORT) && + boot_cpu_has(X86_FEATURE_TSX_FORCE_ABORT)) { + tsx_ctrl_state = TSX_CTRL_RTM_ALWAYS_ABORT; + tsx_clear_cpuid(); + setup_clear_cpu_cap(X86_FEATURE_RTM); + setup_clear_cpu_cap(X86_FEATURE_HLE); return; + } + + if (!tsx_ctrl_is_supported()) { + tsx_ctrl_state = TSX_CTRL_NOT_SUPPORTED; + return; + } ret = cmdline_find_option(boot_command_line, "tsx", arg, sizeof(arg)); if (ret >= 0) { |