[Xen-changelog] [xen stable-4.8] x86: split opt_xpti

[p***@xen.org]

commit 38a7dded19e30f1cea620db46738ef39579517f5
Author: Jan Beulich <***@suse.com>
AuthorDate: Mon Nov 5 16:13:55 2018 +0100
Commit: Jan Beulich <***@suse.com>
CommitDate: Mon Nov 5 16:13:55 2018 +0100

x86: split opt_xpti

Use separate tracking variables for the hardware domain and DomU-s.

No functional change intended.

Signed-off-by: Jan Beulich <***@suse.com>
Acked-by: Andrew Cooper <***@citrix.com>
master commit: 51e0cb45932d80d4eeb59994ee2c3f3c597b0212
master date: 2018-10-04 14:48:18 +0200
---
xen/arch/x86/domain.c | 4 ++--
xen/arch/x86/spec_ctrl.c | 52 +++++++++++++++++++++++++----------------
xen/include/asm-x86/spec_ctrl.h | 4 +---
3 files changed, 35 insertions(+), 25 deletions(-)

diff --git a/xen/arch/x86/domain.c b/xen/arch/x86/domain.c
index 2e2c1a9b2e..2f43986576 100644
--- a/xen/arch/x86/domain.c
+++ b/xen/arch/x86/domain.c
@@ -386,8 +386,8 @@ static void set_domain_xpti(struct domain *d)
}
else
{
- d->arch.pv_domain.xpti = opt_xpti & (is_hardware_domain(d)
- ? OPT_XPTI_DOM0 : OPT_XPTI_DOMU);
+ d->arch.pv_domain.xpti = is_hardware_domain(d) ? opt_xpti_hwdom
+ : opt_xpti_domu;

if ( use_invpcid && cpu_has_pcid )
switch ( opt_pcid )
diff --git a/xen/arch/x86/spec_ctrl.c b/xen/arch/x86/spec_ctrl.c
index 559f2bd806..afa9602580 100644
--- a/xen/arch/x86/spec_ctrl.c
+++ b/xen/arch/x86/spec_ctrl.c
@@ -117,8 +117,10 @@ static int __init parse_spec_ctrl(char *s)

opt_eager_fpu = 0;

- if ( opt_xpti < 0 )
- opt_xpti = 0;
+ if ( opt_xpti_hwdom < 0 )
+ opt_xpti_hwdom = 0;
+ if ( opt_xpti_domu < 0 )
+ opt_xpti_domu = 0;

if ( opt_smt < 0 )
opt_smt = 1;
@@ -326,8 +328,8 @@ static void __init print_details(enum ind_thunk thunk, uint64_t caps)
opt_eager_fpu ? " EAGER_FPU" : "");

printk(" XPTI (64-bit PV only): Dom0 %s, DomU %s\n",
- opt_xpti & OPT_XPTI_DOM0 ? "enabled" : "disabled",
- opt_xpti & OPT_XPTI_DOMU ? "enabled" : "disabled");
+ opt_xpti_hwdom ? "enabled" : "disabled",
+ opt_xpti_domu ? "enabled" : "disabled");

printk(" PV L1TF shadowing: Dom0 %s, DomU %s\n",
opt_pv_l1tf & OPT_PV_L1TF_DOM0 ? "enabled" : "disabled",
@@ -640,7 +642,8 @@ static __init void l1tf_calculations(uint64_t caps)
: (3ul << (paddr_bits - 2))));
}

-int8_t __read_mostly opt_xpti = -1;
+int8_t __read_mostly opt_xpti_hwdom = -1;
+int8_t __read_mostly opt_xpti_domu = -1;

static __init void xpti_init_default(uint64_t caps)
{
@@ -648,9 +651,19 @@ static __init void xpti_init_default(uint64_t caps)
caps = ARCH_CAPABILITIES_RDCL_NO;

if ( caps & ARCH_CAPABILITIES_RDCL_NO )
- opt_xpti = 0;
+ {
+ if ( opt_xpti_hwdom < 0 )
+ opt_xpti_hwdom = 0;
+ if ( opt_xpti_domu < 0 )
+ opt_xpti_domu = 0;
+ }
else
- opt_xpti = OPT_XPTI_DOM0 | OPT_XPTI_DOMU;
+ {
+ if ( opt_xpti_hwdom < 0 )
+ opt_xpti_hwdom = 1;
+ if ( opt_xpti_domu < 0 )
+ opt_xpti_domu = 1;
+ }
}

static __init int parse_xpti(char *s)
@@ -659,12 +672,14 @@ static __init int parse_xpti(char *s)
int val, rc = 0;

/* Inhibit the defaults as an explicit choice has been given. */
- if ( opt_xpti == -1 )
- opt_xpti = 0;
+ if ( opt_xpti_hwdom == -1 )
+ opt_xpti_hwdom = 0;
+ if ( opt_xpti_domu == -1 )
+ opt_xpti_domu = 0;

/* Interpret 'xpti' alone in its positive boolean form. */
if ( *s == '\0' )
- opt_xpti = OPT_XPTI_DOM0 | OPT_XPTI_DOMU;
+ opt_xpti_hwdom = opt_xpti_domu = 1;

do {
ss = strchr(s, ',');
@@ -674,22 +689,20 @@ static __init int parse_xpti(char *s)
switch ( parse_bool(s) )
{
case 0:
- opt_xpti = 0;
+ opt_xpti_hwdom = opt_xpti_domu = 0;
break;

case 1:
- opt_xpti = OPT_XPTI_DOM0 | OPT_XPTI_DOMU;
+ opt_xpti_hwdom = opt_xpti_domu = 1;
break;

default:
if ( !strcmp(s, "default") )
- opt_xpti = -1;
+ opt_xpti_hwdom = opt_xpti_domu = -1;
else if ( (val = parse_boolean("dom0", s, ss)) >= 0 )
- opt_xpti = (opt_xpti & ~OPT_XPTI_DOM0) |
- (val ? OPT_XPTI_DOM0 : 0);
+ opt_xpti_hwdom = val;
else if ( (val = parse_boolean("domu", s, ss)) >= 0 )
- opt_xpti = (opt_xpti & ~OPT_XPTI_DOMU) |
- (val ? OPT_XPTI_DOMU : 0);
+ opt_xpti_domu = val;
else if ( *s )
rc = -EINVAL;
break;
@@ -845,10 +858,9 @@ void __init init_speculation_mitigations(void)
if ( default_xen_spec_ctrl )
setup_force_cpu_cap(X86_FEATURE_SC_MSR_IDLE);

- if ( opt_xpti == -1 )
- xpti_init_default(caps);
+ xpti_init_default(caps);

- if ( opt_xpti == 0 )
+ if ( !opt_xpti_hwdom && !opt_xpti_domu )
setup_force_cpu_cap(X86_FEATURE_NO_XPTI);
else
setup_clear_cpu_cap(X86_FEATURE_NO_XPTI);
diff --git a/xen/include/asm-x86/spec_ctrl.h b/xen/include/asm-x86/spec_ctrl.h
index 8f8aad40bb..1b29f45b1b 100644
--- a/xen/include/asm-x86/spec_ctrl.h
+++ b/xen/include/asm-x86/spec_ctrl.h
@@ -35,9 +35,7 @@ extern bool bsp_delay_spec_ctrl;
extern uint8_t default_xen_spec_ctrl;
extern uint8_t default_spec_ctrl_flags;

-extern int8_t opt_xpti;
-#define OPT_XPTI_DOM0 0x01
-#define OPT_XPTI_DOMU 0x02
+extern int8_t opt_xpti_hwdom, opt_xpti_domu;

extern int8_t opt_pv_l1tf;
#define OPT_PV_L1TF_DOM0 0x01
--
generated by git-patchbot for /home/xen/git/xen.git#stable-4.8