From 96756435367d04df15c54c804607006a707c75b4 Mon Sep 17 00:00:00 2001
From: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Date: Thu, 1 Dec 2022 12:19:35 -0800
Subject: [PATCH] x86/tsx: Add a feature bit for TSX control MSR support
stable inclusion
from stable-v5.10.158
commit 5e3d4a68e2e11dbe561fa7de919ff9c82547a215
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I7NTXH
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=5e3d4a68e2e11dbe561fa7de919ff9c82547a215
--------------------------------
commit aaa65d17eec372c6a9756833f3964ba05b05ea14 upstream.
Support for the TSX control MSR is enumerated in MSR_IA32_ARCH_CAPABILITIES.
This is different from how other CPU features are enumerated i.e. via
CPUID. Currently, a call to tsx_ctrl_is_supported() is required for
enumerating the feature. In the absence of a feature bit for TSX control,
any code that relies on checking feature bits directly will not work.
In preparation for adding a feature bit check in MSR save/restore
during suspend/resume, set a new feature bit X86_FEATURE_TSX_CTRL when
MSR_IA32_TSX_CTRL is present.
[ bp: Remove tsx_ctrl_is_supported()]
[Pawan: Resolved conflicts in backport; Removed parts of commit message
referring to removed function tsx_ctrl_is_supported()]
Suggested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: <stable@kernel.org>
Link: https://lore.kernel.org/r/de619764e1d98afbb7a5fa58424f1278ede37b45.1668539735.git.pawan.kumar.gupta@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: sanglipeng <sanglipeng1@jd.com>
Conflicts:
arch/x86/include/asm/cpufeatures.h
---
arch/x86/include/asm/cpufeatures.h | 1 +
arch/x86/kernel/cpu/tsx.c | 33 +++++++++++++-----------------
2 files changed, 15 insertions(+), 19 deletions(-)
diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h
index 95871c73be78..0c87926f3c31 100644
--- a/arch/x86/include/asm/cpufeatures.h
+++ b/arch/x86/include/asm/cpufeatures.h
@@ -323,6 +323,7 @@
#define X86_FEATURE_USE_IBPB_FW (11*32+16) /* "" Use IBPB during runtime firmware calls */
#define X86_FEATURE_RSB_VMEXIT_LITE (11*32+17) /* "" Fill RSB on VM exit when EIBRS is enabled */
#define X86_FEATURE_SGX_EDECCSSA (11*32+18) /* "" SGX EDECCSSA user leaf function */
+#define X86_FEATURE_MSR_TSX_CTRL (11*32+19) /* "" MSR IA32_TSX_CTRL (Intel) implemented */
/* Intel-defined CPU features, CPUID level 0x00000007:1 (EAX), word 12 */
#define X86_FEATURE_AVX_VNNI (12*32+ 4) /* AVX VNNI instructions */
diff --git a/arch/x86/kernel/cpu/tsx.c b/arch/x86/kernel/cpu/tsx.c
index e2ad30e474f8..da06bbb5d68e 100644
--- a/arch/x86/kernel/cpu/tsx.c
+++ b/arch/x86/kernel/cpu/tsx.c
@@ -58,24 +58,6 @@ void tsx_enable(void)
wrmsrl(MSR_IA32_TSX_CTRL, tsx);
}
-static bool __init tsx_ctrl_is_supported(void)
-{
- u64 ia32_cap = x86_read_arch_cap_msr();
-
- /*
- * TSX is controlled via MSR_IA32_TSX_CTRL. However, support for this
- * MSR is enumerated by ARCH_CAP_TSX_MSR bit in MSR_IA32_ARCH_CAPABILITIES.
- *
- * TSX control (aka MSR_IA32_TSX_CTRL) is only available after a
- * microcode update on CPUs that have their MSR_IA32_ARCH_CAPABILITIES
- * bit MDS_NO=1. CPUs with MDS_NO=0 are not planned to get
- * MSR_IA32_TSX_CTRL support even after a microcode update. Thus,
- * tsx= cmdline requests will do nothing on CPUs without
- * MSR_IA32_TSX_CTRL support.
- */
- return !!(ia32_cap & ARCH_CAP_TSX_CTRL_MSR);
-}
-
static enum tsx_ctrl_states x86_get_tsx_auto_mode(void)
{
if (boot_cpu_has_bug(X86_BUG_TAA))
@@ -89,9 +71,22 @@ void __init tsx_init(void)
char arg[5] = {};
int ret;
- if (!tsx_ctrl_is_supported())
+ /*
+ * TSX is controlled via MSR_IA32_TSX_CTRL. However, support for this
+ * MSR is enumerated by ARCH_CAP_TSX_MSR bit in MSR_IA32_ARCH_CAPABILITIES.
+ *
+ * TSX control (aka MSR_IA32_TSX_CTRL) is only available after a
+ * microcode update on CPUs that have their MSR_IA32_ARCH_CAPABILITIES
+ * bit MDS_NO=1. CPUs with MDS_NO=0 are not planned to get
+ * MSR_IA32_TSX_CTRL support even after a microcode update. Thus,
+ * tsx= cmdline requests will do nothing on CPUs without
+ * MSR_IA32_TSX_CTRL support.
+ */
+ if (!(x86_read_arch_cap_msr() & ARCH_CAP_TSX_CTRL_MSR))
return;
+ setup_force_cpu_cap(X86_FEATURE_MSR_TSX_CTRL);
+
ret = cmdline_find_option(boot_command_line, "tsx", arg, sizeof(arg));
if (ret >= 0) {
if (!strcmp(arg, "on")) {
--
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