[Xen-changelog] [xen master] x86/domctl: Implement XEN_DOMCTL_get_cpu_policy

[p***@xen.org]

commit 60529dfeca145a8ec00f5813a4c7179f0c1bfb97
Author: Sergey Dyasli <***@citrix.com>
AuthorDate: Thu Jun 21 16:35:50 2018 +0200
Commit: Andrew Cooper <***@citrix.com>
CommitDate: Tue Nov 6 17:51:18 2018 +0000

x86/domctl: Implement XEN_DOMCTL_get_cpu_policy

This finally (after literally years of work!) marks the point where the
toolstack can ask the hypervisor for the current CPUID configuration of a
specific domain.

Introduce a new flask access vector and update the default policies.

Also extend xen-cpuid's --policy mode to be able to take a domid and dump a
specific domains CPUID and MSR policy.

Signed-off-by: Andrew Cooper <***@citrix.com>
Signed-off-by: Sergey Dyasli <***@citrix.com>
Acked-by: Daniel De Graaf <***@tycho.nsa.gov>
Reviewed-by: Jan Beulich <***@suse.com>
Acked-by: Wei Liu <***@citrix.com>
---
tools/flask/policy/modules/dom0.te | 2 +-
tools/flask/policy/modules/xen.if | 2 +-
tools/libxc/include/xenctrl.h | 3 ++
tools/libxc/xc_cpuid_x86.c | 38 ++++++++++++++++++++++++
tools/misc/xen-cpuid.c | 58 ++++++++++++++++++++++++++++++++-----
xen/arch/x86/domctl.c | 22 ++++++++++++++
xen/include/public/domctl.h | 18 ++++++++++++
xen/xsm/flask/hooks.c | 3 ++
xen/xsm/flask/policy/access_vectors | 2 ++
9 files changed, 138 insertions(+), 10 deletions(-)

diff --git a/tools/flask/policy/modules/dom0.te b/tools/flask/policy/modules/dom0.te
index dfdcdcd128..c7d565d3dc 100644
--- a/tools/flask/policy/modules/dom0.te
+++ b/tools/flask/policy/modules/dom0.te
@@ -39,7 +39,7 @@ allow dom0_t dom0_t:domain {
};
allow dom0_t dom0_t:domain2 {
set_cpuid gettsc settsc setscheduler set_vnumainfo
- get_vnumainfo psr_cmt_op psr_alloc
+ get_vnumainfo psr_cmt_op psr_alloc get_cpu_policy
};
allow dom0_t dom0_t:resource { add remove };

diff --git a/tools/flask/policy/modules/xen.if b/tools/flask/policy/modules/xen.if
index 4e06cfc09b..de5fb331bf 100644
--- a/tools/flask/policy/modules/xen.if
+++ b/tools/flask/policy/modules/xen.if
@@ -53,7 +53,7 @@ define(`create_domain_common', `
allow $1 $2:domain2 { set_cpuid settsc setscheduler setclaim
set_vnumainfo get_vnumainfo cacheflush
psr_cmt_op psr_alloc soft_reset
- resource_map };
+ resource_map get_cpu_policy };
allow $1 $2:security check_context;
allow $1 $2:shadow enable;
allow $1 $2:mmu { map_read map_write adjust memorymap physmap pinpage mmuext_op updatemp };
diff --git a/tools/libxc/include/xenctrl.h b/tools/libxc/include/xenctrl.h
index 74fa88b9bf..97ae965be7 100644
--- a/tools/libxc/include/xenctrl.h
+++ b/tools/libxc/include/xenctrl.h
@@ -2538,6 +2538,9 @@ int xc_get_cpu_policy_size(xc_interface *xch, uint32_t *nr_leaves,
int xc_get_system_cpu_policy(xc_interface *xch, uint32_t index,
uint32_t *nr_leaves, xen_cpuid_leaf_t *leaves,
uint32_t *nr_msrs, xen_msr_entry_t *msrs);
+int xc_get_domain_cpu_policy(xc_interface *xch, uint32_t domid,
+ uint32_t *nr_leaves, xen_cpuid_leaf_t *leaves,
+ uint32_t *nr_msrs, xen_msr_entry_t *msrs);

uint32_t xc_get_cpu_featureset_size(void);

diff --git a/tools/libxc/xc_cpuid_x86.c b/tools/libxc/xc_cpuid_x86.c
index 00e27f0c0e..9e47fc8754 100644
--- a/tools/libxc/xc_cpuid_x86.c
+++ b/tools/libxc/xc_cpuid_x86.c
@@ -189,6 +189,44 @@ int xc_get_system_cpu_policy(xc_interface *xch, uint32_t index,
return ret;
}

+int xc_get_domain_cpu_policy(xc_interface *xch, uint32_t domid,
+ uint32_t *nr_leaves, xen_cpuid_leaf_t *leaves,
+ uint32_t *nr_msrs, xen_msr_entry_t *msrs)
+{
+ DECLARE_DOMCTL;
+ DECLARE_HYPERCALL_BOUNCE(leaves,
+ *nr_leaves * sizeof(*leaves),
+ XC_HYPERCALL_BUFFER_BOUNCE_OUT);
+ DECLARE_HYPERCALL_BOUNCE(msrs,
+ *nr_msrs * sizeof(*msrs),
+ XC_HYPERCALL_BUFFER_BOUNCE_OUT);
+ int ret;
+
+ if ( xc_hypercall_bounce_pre(xch, leaves) ||
+ xc_hypercall_bounce_pre(xch, msrs) )
+ return -1;
+
+ domctl.cmd = XEN_DOMCTL_get_cpu_policy;
+ domctl.domain = domid;
+ domctl.u.cpu_policy.nr_leaves = *nr_leaves;
+ set_xen_guest_handle(domctl.u.cpu_policy.cpuid_policy, leaves);
+ domctl.u.cpu_policy.nr_msrs = *nr_msrs;
+ set_xen_guest_handle(domctl.u.cpu_policy.msr_policy, msrs);
+
+ ret = do_domctl(xch, &domctl);
+
+ xc_hypercall_bounce_post(xch, leaves);
+ xc_hypercall_bounce_post(xch, msrs);
+
+ if ( !ret )
+ {
+ *nr_leaves = domctl.u.cpu_policy.nr_leaves;
+ *nr_msrs = domctl.u.cpu_policy.nr_msrs;
+ }
+
+ return ret;
+}
+
struct cpuid_domain_info
{
enum
diff --git a/tools/misc/xen-cpuid.c b/tools/misc/xen-cpuid.c
index 95ed853295..2c41031497 100644
--- a/tools/misc/xen-cpuid.c
+++ b/tools/misc/xen-cpuid.c
@@ -3,6 +3,8 @@
#include <err.h>
#include <getopt.h>
#include <string.h>
+#include <errno.h>
+#include <limits.h>

#include <xenctrl.h>

@@ -309,11 +311,13 @@ int main(int argc, char **argv)
{
enum { MODE_UNKNOWN, MODE_INFO, MODE_DETAIL, MODE_INTERPRET, MODE_POLICY }
mode = MODE_UNKNOWN;
+ int domid = -1;

nr_features = xc_get_cpu_featureset_size();

for ( ;; )
{
+ const char *tmp_optarg;
int option_index = 0, c;
static struct option long_options[] =
{
@@ -321,11 +325,11 @@ int main(int argc, char **argv)
{ "info", no_argument, NULL, 'i' },
{ "detail", no_argument, NULL, 'd' },
{ "verbose", no_argument, NULL, 'v' },
- { "policy", no_argument, NULL, 'p' },
+ { "policy", optional_argument, NULL, 'p' },
{ NULL, 0, NULL, 0 },
};

- c = getopt_long(argc, argv, "hidvp", long_options, &option_index);
+ c = getopt_long(argc, argv, "hidvp::", long_options, &option_index);

if ( c == -1 )
break;
@@ -345,6 +349,24 @@ int main(int argc, char **argv)

case 'p':
mode = MODE_POLICY;
+
+ tmp_optarg = optarg;
+
+ /* Make "--policy $DOMID" and "-p $DOMID" work. */
+ if ( !optarg && optind < argc &&
+ argv[optind] != NULL && argv[optind][0] != '\0' &&
+ argv[optind][0] != '-' )
+ tmp_optarg = argv[optind++];
+
+ if ( tmp_optarg )
+ {
+ char *endptr;
+
+ errno = 0;
+ domid = strtol(tmp_optarg, &endptr, 0);
+ if ( errno || endptr == tmp_optarg )
+ err(1, "strtol(%s,,)", tmp_optarg);
+ }
break;

case 'd':
@@ -398,8 +420,9 @@ int main(int argc, char **argv)

if ( xc_get_cpu_policy_size(xch, &max_leaves, &max_msrs) )
err(1, "xc_get_cpu_policy_size(...)");
- printf("Xen reports there are maximum %u leaves and %u MSRs\n",
- max_leaves, max_msrs);
+ if ( domid == -1 )
+ printf("Xen reports there are maximum %u leaves and %u MSRs\n",
+ max_leaves, max_msrs);

leaves = calloc(max_leaves, sizeof(xen_cpuid_leaf_t));
if ( !leaves )
@@ -408,16 +431,35 @@ int main(int argc, char **argv)
if ( !msrs )
err(1, "calloc(max_msrs)");

- for ( i = 0; i < ARRAY_SIZE(sys_policies); ++i )
+ if ( domid != -1 )
{
+ char name[20];
uint32_t nr_leaves = max_leaves;
uint32_t nr_msrs = max_msrs;

- if ( xc_get_system_cpu_policy(xch, i, &nr_leaves, leaves,
+ if ( xc_get_domain_cpu_policy(xch, domid, &nr_leaves, leaves,
&nr_msrs, msrs) )
- err(1, "xc_get_system_cpu_policy(, %s,,)", sys_policies[i]);
+ err(1, "xc_get_domain_cpu_policy(, %d, %d,, %d,)",
+ domid, nr_leaves, nr_msrs);

- print_policy(sys_policies[i], leaves, nr_leaves, msrs, nr_msrs);
+ snprintf(name, sizeof(name), "Domain %d", domid);
+ print_policy(name, leaves, nr_leaves, msrs, nr_msrs);
+ }
+ else
+ {
+ /* Get system policies */
+ for ( i = 0; i < ARRAY_SIZE(sys_policies); ++i )
+ {
+ uint32_t nr_leaves = max_leaves;
+ uint32_t nr_msrs = max_msrs;
+
+ if ( xc_get_system_cpu_policy(xch, i, &nr_leaves, leaves,
+ &nr_msrs, msrs) )
+ err(1, "xc_get_system_cpu_policy(, %s,,)", sys_policies[i]);
+
+ print_policy(sys_policies[i], leaves, nr_leaves,
+ msrs, nr_msrs);
+ }
}

free(leaves);
diff --git a/xen/arch/x86/domctl.c b/xen/arch/x86/domctl.c
index 33f9a869c0..175a0c9ae0 100644
--- a/xen/arch/x86/domctl.c
+++ b/xen/arch/x86/domctl.c
@@ -1542,6 +1542,28 @@ long arch_do_domctl(
recalculate_cpuid_policy(d);
break;

+ case XEN_DOMCTL_get_cpu_policy:
+ /* Process the CPUID leaves. */
+ if ( guest_handle_is_null(domctl->u.cpu_policy.cpuid_policy) )
+ domctl->u.cpu_policy.nr_leaves = CPUID_MAX_SERIALISED_LEAVES;
+ else if ( (ret = x86_cpuid_copy_to_buffer(
+ d->arch.cpuid,
+ domctl->u.cpu_policy.cpuid_policy,
+ &domctl->u.cpu_policy.nr_leaves)) )
+ break;
+
+ /* Process the MSR entries. */
+ if ( guest_handle_is_null(domctl->u.cpu_policy.msr_policy) )
+ domctl->u.cpu_policy.nr_msrs = MSR_MAX_SERIALISED_ENTRIES;
+ else if ( (ret = x86_msr_copy_to_buffer(
+ d->arch.msr,
+ domctl->u.cpu_policy.msr_policy,
+ &domctl->u.cpu_policy.nr_msrs)) )
+ break;
+
+ copyback = true;
+ break;
+
default:
ret = iommu_do_domctl(domctl, d, u_domctl);
break;
diff --git a/xen/include/public/domctl.h b/xen/include/public/domctl.h
index 1bbdcd9f8a..4a46c28eed 100644
--- a/xen/include/public/domctl.h
+++ b/xen/include/public/domctl.h
@@ -652,6 +652,22 @@ struct xen_domctl_cpuid {
uint32_t ecx;
uint32_t edx;
};
+
+/*
+ * XEN_DOMCTL_get_cpu_policy (x86 specific)
+ *
+ * Query the CPUID and MSR policies for a specific domain.
+ */
+struct xen_domctl_cpu_policy {
+ uint32_t nr_leaves; /* IN/OUT: Number of leaves in/written to
+ * 'cpuid_policy'. */
+ uint32_t nr_msrs; /* IN/OUT: Number of MSRs in/written to
+ * 'msr_domain_policy' */
+ XEN_GUEST_HANDLE_64(xen_cpuid_leaf_t) cpuid_policy; /* OUT */
+ XEN_GUEST_HANDLE_64(xen_msr_entry_t) msr_policy; /* OUT */
+};
+typedef struct xen_domctl_cpu_policy xen_domctl_cpu_policy_t;
+DEFINE_XEN_GUEST_HANDLE(xen_domctl_cpu_policy_t);
#endif

/*
@@ -1177,6 +1193,7 @@ struct xen_domctl {
#define XEN_DOMCTL_soft_reset 79
/* #define XEN_DOMCTL_set_gnttab_limits 80 - Moved into XEN_DOMCTL_createdomain */
#define XEN_DOMCTL_vuart_op 81
+#define XEN_DOMCTL_get_cpu_policy 82
#define XEN_DOMCTL_gdbsx_guestmemio 1000
#define XEN_DOMCTL_gdbsx_pausevcpu 1001
#define XEN_DOMCTL_gdbsx_unpausevcpu 1002
@@ -1221,6 +1238,7 @@ struct xen_domctl {
struct xen_domctl_mem_sharing_op mem_sharing_op;
#if defined(__i386__) || defined(__x86_64__)
struct xen_domctl_cpuid cpuid;
+ struct xen_domctl_cpu_policy cpu_policy;
struct xen_domctl_vcpuextstate vcpuextstate;
struct xen_domctl_vcpu_msrs vcpu_msrs;
#endif
diff --git a/xen/xsm/flask/hooks.c b/xen/xsm/flask/hooks.c
index e5b0c60220..96d31aaf08 100644
--- a/xen/xsm/flask/hooks.c
+++ b/xen/xsm/flask/hooks.c
@@ -742,6 +742,9 @@ static int flask_domctl(struct domain *d, int cmd)
case XEN_DOMCTL_soft_reset:
return current_has_perm(d, SECCLASS_DOMAIN2, DOMAIN2__SOFT_RESET);

+ case XEN_DOMCTL_get_cpu_policy:
+ return current_has_perm(d, SECCLASS_DOMAIN2, DOMAIN2__GET_CPU_POLICY);
+
default:
return avc_unknown_permission("domctl", cmd);
}
diff --git a/xen/xsm/flask/policy/access_vectors b/xen/xsm/flask/policy/access_vectors
index e58a50d810..6fecfdaa83 100644
--- a/xen/xsm/flask/policy/access_vectors
+++ b/xen/xsm/flask/policy/access_vectors
@@ -248,6 +248,8 @@ class domain2
psr_alloc
# XENMEM_resource_map
resource_map
+# XEN_DOMCTL_get_cpu_policy
+ get_cpu_policy
}

# Similar to class domain, but primarily contains domctls related to HVM domains
--
generated by git-patchbot for /home/xen/git/xen.git#master