[PATCH 5.5 066/367] x86/cpu: Update cached HLE state on write to TSX_CTRL_CPUID_CLEAR

Greg Kroah-Hartman
2020-02-10T12:51:51Z

From: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>

commit 5efc6fa9044c3356d6046c6e1da6d02572dbed6b upstream.

/proc/cpuinfo currently reports Hardware Lock Elision (HLE) feature to
be present on boot cpu even if it was disabled during the bootup. This
is because cpuinfo_x86->x86_capability HLE bit is not updated after TSX
state is changed via the new MSR IA32_TSX_CTRL.

Update the cached HLE bit also since it is expected to change after an
update to CPUID_CLEAR bit in MSR IA32_TSX_CTRL.

Fixes: 95c5824f75f3 ("x86/cpu: Add a "tsx=" cmdline option with TSX disabled by default")
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Neelima Krishnan <neelima.krishnan@intel.com>
Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/2529b99546294c893dfa1c89e2b3e46da3369a59.1578685425.git.pawan.kumar.gupta@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
arch/x86/kernel/cpu/tsx.c | 13 +++++++------
1 file changed, 7 insertions(+), 6 deletions(-)

--- a/arch/x86/kernel/cpu/tsx.c
+++ b/arch/x86/kernel/cpu/tsx.c
@@ -115,11 +115,12 @@ void __init tsx_init(void)
tsx_disable();

/*
- * tsx_disable() will change the state of the
- * RTM CPUID bit. Clear it here since it is now
- * expected to be not set.
+ * tsx_disable() will change the state of the RTM and HLE CPUID
+ * bits. Clear them here since they are now expected to be not
+ * set.
*/
setup_clear_cpu_cap(X86_FEATURE_RTM);
+ setup_clear_cpu_cap(X86_FEATURE_HLE);
} else if (tsx_ctrl_state == TSX_CTRL_ENABLE) {

/*
@@ -131,10 +132,10 @@ void __init tsx_init(void)
tsx_enable();

/*
- * tsx_enable() will change the state of the
- * RTM CPUID bit. Force it here since it is now
- * expected to be set.
+ * tsx_enable() will change the state of the RTM and HLE CPUID
+ * bits. Force them here since they are now expected to be set.
*/
setup_force_cpu_cap(X86_FEATURE_RTM);
+ setup_force_cpu_cap(X86_FEATURE_HLE);
}
}