[tip:x86/pti] x86/speculation: Move STIPB/IBPB string conditionals out of cpu_show_common()
Commit-ID: a8f76ae41cd633ac00be1b3019b1eb4741be3828
Gitweb: https://git.kernel.org/tip/a8f76ae41cd633ac00be1b3019b1eb4741be3828
Author: Tim Chen
AuthorDate: Sun, 25 Nov 2018 19:33:32 +0100
Committer: Thomas Gleixner
CommitDate: Wed, 28 Nov 2018 11:57:05 +0100
x86/speculation: Move STIPB/IBPB string conditionals out of cpu_show_common()
The Spectre V2 printout in cpu_show_common() handles conditionals for the
various mitigation methods directly in the sprintf() argument list. That's
hard to read and will become unreadable if more complex decisions need to
be made for a particular method.
Move the conditionals for STIBP and IBPB string selection into helper
functions, so they can be extended later on.
Signed-off-by: Tim Chen
Signed-off-by: Thomas Gleixner
Reviewed-by: Ingo Molnar
Cc: Peter Zijlstra
Cc: Andy Lutomirski
Cc: Linus Torvalds
Cc: Jiri Kosina
Cc: Tom Lendacky
Cc: Josh Poimboeuf
Cc: Andrea Arcangeli
Cc: David Woodhouse
Cc: Andi Kleen
Cc: Dave Hansen
Cc: Casey Schaufler
Cc: Asit Mallick
Cc: Arjan van de Ven
Cc: Jon Masters
Cc: Waiman Long
Cc: Greg KH
Cc: Dave Stewart
Cc: Kees Cook
Cc: sta...@vger.kernel.org
Link: https://lkml.kernel.org/r/20181125185003.874479...@linutronix.de
---
arch/x86/kernel/cpu/bugs.c | 20 ++--
1 file changed, 18 insertions(+), 2 deletions(-)
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index b52a48966e01..a1502bce9eb8 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -844,6 +844,22 @@ static ssize_t l1tf_show_state(char *buf)
}
#endif
+static char *stibp_state(void)
+{
+ if (x86_spec_ctrl_base & SPEC_CTRL_STIBP)
+ return ", STIBP";
+ else
+ return "";
+}
+
+static char *ibpb_state(void)
+{
+ if (boot_cpu_has(X86_FEATURE_USE_IBPB))
+ return ", IBPB";
+ else
+ return "";
+}
+
static ssize_t cpu_show_common(struct device *dev, struct device_attribute
*attr,
char *buf, unsigned int bug)
{
@@ -865,9 +881,9 @@ static ssize_t cpu_show_common(struct device *dev, struct
device_attribute *attr
case X86_BUG_SPECTRE_V2:
return sprintf(buf, "%s%s%s%s%s%s\n",
spectre_v2_strings[spectre_v2_enabled],
- boot_cpu_has(X86_FEATURE_USE_IBPB) ? ", IBPB" :
"",
+ ibpb_state(),
boot_cpu_has(X86_FEATURE_USE_IBRS_FW) ? ",
IBRS_FW" : "",
- (x86_spec_ctrl_base & SPEC_CTRL_STIBP) ? ",
STIBP" : "",
+ stibp_state(),
boot_cpu_has(X86_FEATURE_RSB_CTXSW) ? ", RSB
filling" : "",
spectre_v2_module_string());
[tip:x86/pti] x86/speculation: Move STIPB/IBPB string conditionals out of cpu_show_common()
Commit-ID: a8f76ae41cd633ac00be1b3019b1eb4741be3828
Gitweb: https://git.kernel.org/tip/a8f76ae41cd633ac00be1b3019b1eb4741be3828
Author: Tim Chen
AuthorDate: Sun, 25 Nov 2018 19:33:32 +0100
Committer: Thomas Gleixner
CommitDate: Wed, 28 Nov 2018 11:57:05 +0100
x86/speculation: Move STIPB/IBPB string conditionals out of cpu_show_common()
The Spectre V2 printout in cpu_show_common() handles conditionals for the
various mitigation methods directly in the sprintf() argument list. That's
hard to read and will become unreadable if more complex decisions need to
be made for a particular method.
Move the conditionals for STIBP and IBPB string selection into helper
functions, so they can be extended later on.
Signed-off-by: Tim Chen
Signed-off-by: Thomas Gleixner
Reviewed-by: Ingo Molnar
Cc: Peter Zijlstra
Cc: Andy Lutomirski
Cc: Linus Torvalds
Cc: Jiri Kosina
Cc: Tom Lendacky
Cc: Josh Poimboeuf
Cc: Andrea Arcangeli
Cc: David Woodhouse
Cc: Andi Kleen
Cc: Dave Hansen
Cc: Casey Schaufler
Cc: Asit Mallick
Cc: Arjan van de Ven
Cc: Jon Masters
Cc: Waiman Long
Cc: Greg KH
Cc: Dave Stewart
Cc: Kees Cook
Cc: sta...@vger.kernel.org
Link: https://lkml.kernel.org/r/20181125185003.874479...@linutronix.de
---
arch/x86/kernel/cpu/bugs.c | 20 ++--
1 file changed, 18 insertions(+), 2 deletions(-)
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index b52a48966e01..a1502bce9eb8 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -844,6 +844,22 @@ static ssize_t l1tf_show_state(char *buf)
}
#endif
+static char *stibp_state(void)
+{
+ if (x86_spec_ctrl_base & SPEC_CTRL_STIBP)
+ return ", STIBP";
+ else
+ return "";
+}
+
+static char *ibpb_state(void)
+{
+ if (boot_cpu_has(X86_FEATURE_USE_IBPB))
+ return ", IBPB";
+ else
+ return "";
+}
+
static ssize_t cpu_show_common(struct device *dev, struct device_attribute
*attr,
char *buf, unsigned int bug)
{
@@ -865,9 +881,9 @@ static ssize_t cpu_show_common(struct device *dev, struct
device_attribute *attr
case X86_BUG_SPECTRE_V2:
return sprintf(buf, "%s%s%s%s%s%s\n",
spectre_v2_strings[spectre_v2_enabled],
- boot_cpu_has(X86_FEATURE_USE_IBPB) ? ", IBPB" :
"",
+ ibpb_state(),
boot_cpu_has(X86_FEATURE_USE_IBRS_FW) ? ",
IBRS_FW" : "",
- (x86_spec_ctrl_base & SPEC_CTRL_STIBP) ? ",
STIBP" : "",
+ stibp_state(),
boot_cpu_has(X86_FEATURE_RSB_CTXSW) ? ", RSB
filling" : "",
spectre_v2_module_string());
