1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
|
From f30cba1d35ebb9a07ebd54253086280080b366a6 Mon Sep 17 00:00:00 2001
From: Borislav Petkov <bp@suse.de>
Date: Sat, 12 May 2018 00:14:51 +0200
Subject: [PATCH 72/93] x86/bugs: Unify x86_spec_ctrl_{set_guest,restore_host}
commit cc69b34989210f067b2c51d5539b5f96ebcc3a01 upstream
Function bodies are very similar and are going to grow more almost
identical code. Add a bool arg to determine whether SPEC_CTRL is being set
for the guest or restored to the host.
No functional changes.
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
arch/x86/include/asm/spec-ctrl.h | 33 +++++++++++++++++++---
arch/x86/kernel/cpu/bugs.c | 60 ++++++++++------------------------------
2 files changed, 44 insertions(+), 49 deletions(-)
diff --git a/arch/x86/include/asm/spec-ctrl.h b/arch/x86/include/asm/spec-ctrl.h
index 82b6c5a..9cecbe5 100644
--- a/arch/x86/include/asm/spec-ctrl.h
+++ b/arch/x86/include/asm/spec-ctrl.h
@@ -13,10 +13,35 @@
* Takes the guest view of SPEC_CTRL MSR as a parameter and also
* the guest's version of VIRT_SPEC_CTRL, if emulated.
*/
-extern void x86_spec_ctrl_set_guest(u64 guest_spec_ctrl,
- u64 guest_virt_spec_ctrl);
-extern void x86_spec_ctrl_restore_host(u64 guest_spec_ctrl,
- u64 guest_virt_spec_ctrl);
+extern void x86_virt_spec_ctrl(u64 guest_spec_ctrl, u64 guest_virt_spec_ctrl, bool guest);
+
+/**
+ * x86_spec_ctrl_set_guest - Set speculation control registers for the guest
+ * @guest_spec_ctrl: The guest content of MSR_SPEC_CTRL
+ * @guest_virt_spec_ctrl: The guest controlled bits of MSR_VIRT_SPEC_CTRL
+ * (may get translated to MSR_AMD64_LS_CFG bits)
+ *
+ * Avoids writing to the MSR if the content/bits are the same
+ */
+static inline
+void x86_spec_ctrl_set_guest(u64 guest_spec_ctrl, u64 guest_virt_spec_ctrl)
+{
+ x86_virt_spec_ctrl(guest_spec_ctrl, guest_virt_spec_ctrl, true);
+}
+
+/**
+ * x86_spec_ctrl_restore_host - Restore host speculation control registers
+ * @guest_spec_ctrl: The guest content of MSR_SPEC_CTRL
+ * @guest_virt_spec_ctrl: The guest controlled bits of MSR_VIRT_SPEC_CTRL
+ * (may get translated to MSR_AMD64_LS_CFG bits)
+ *
+ * Avoids writing to the MSR if the content/bits are the same
+ */
+static inline
+void x86_spec_ctrl_restore_host(u64 guest_spec_ctrl, u64 guest_virt_spec_ctrl)
+{
+ x86_virt_spec_ctrl(guest_spec_ctrl, guest_virt_spec_ctrl, false);
+}
/* AMD specific Speculative Store Bypass MSR data */
extern u64 x86_amd_ls_cfg_base;
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index eddbdc8..9203150 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -150,55 +150,25 @@ u64 x86_spec_ctrl_get_default(void)
}
EXPORT_SYMBOL_GPL(x86_spec_ctrl_get_default);
-/**
- * x86_spec_ctrl_set_guest - Set speculation control registers for the guest
- * @guest_spec_ctrl: The guest content of MSR_SPEC_CTRL
- * @guest_virt_spec_ctrl: The guest controlled bits of MSR_VIRT_SPEC_CTRL
- * (may get translated to MSR_AMD64_LS_CFG bits)
- *
- * Avoids writing to the MSR if the content/bits are the same
- */
-void x86_spec_ctrl_set_guest(u64 guest_spec_ctrl, u64 guest_virt_spec_ctrl)
+void
+x86_virt_spec_ctrl(u64 guest_spec_ctrl, u64 guest_virt_spec_ctrl, bool setguest)
{
- u64 host = x86_spec_ctrl_base;
+ struct thread_info *ti = current_thread_info();
+ u64 msr, host = x86_spec_ctrl_base;
/* Is MSR_SPEC_CTRL implemented ? */
- if (!static_cpu_has(X86_FEATURE_MSR_SPEC_CTRL))
- return;
-
- /* SSBD controlled in MSR_SPEC_CTRL */
- if (static_cpu_has(X86_FEATURE_SPEC_CTRL_SSBD))
- host |= ssbd_tif_to_spec_ctrl(current_thread_info()->flags);
-
- if (host != guest_spec_ctrl)
- wrmsrl(MSR_IA32_SPEC_CTRL, guest_spec_ctrl);
-}
-EXPORT_SYMBOL_GPL(x86_spec_ctrl_set_guest);
-
-/**
- * x86_spec_ctrl_restore_host - Restore host speculation control registers
- * @guest_spec_ctrl: The guest content of MSR_SPEC_CTRL
- * @guest_virt_spec_ctrl: The guest controlled bits of MSR_VIRT_SPEC_CTRL
- * (may get translated to MSR_AMD64_LS_CFG bits)
- *
- * Avoids writing to the MSR if the content/bits are the same
- */
-void x86_spec_ctrl_restore_host(u64 guest_spec_ctrl, u64 guest_virt_spec_ctrl)
-{
- u64 host = x86_spec_ctrl_base;
-
- /* Is MSR_SPEC_CTRL implemented ? */
- if (!static_cpu_has(X86_FEATURE_MSR_SPEC_CTRL))
- return;
-
- /* SSBD controlled in MSR_SPEC_CTRL */
- if (static_cpu_has(X86_FEATURE_SPEC_CTRL_SSBD))
- host |= ssbd_tif_to_spec_ctrl(current_thread_info()->flags);
-
- if (host != guest_spec_ctrl)
- wrmsrl(MSR_IA32_SPEC_CTRL, host);
+ if (static_cpu_has(X86_FEATURE_MSR_SPEC_CTRL)) {
+ /* SSBD controlled in MSR_SPEC_CTRL */
+ if (static_cpu_has(X86_FEATURE_SPEC_CTRL_SSBD))
+ host |= ssbd_tif_to_spec_ctrl(ti->flags);
+
+ if (host != guest_spec_ctrl) {
+ msr = setguest ? guest_spec_ctrl : host;
+ wrmsrl(MSR_IA32_SPEC_CTRL, msr);
+ }
+ }
}
-EXPORT_SYMBOL_GPL(x86_spec_ctrl_restore_host);
+EXPORT_SYMBOL_GPL(x86_virt_spec_ctrl);
static void x86_amd_ssb_disable(void)
{
--
2.7.4
|
