This functionality is obsolete. It was introduced by c/s 39407bed9c0 into
Xend, but never exposed in libxl.
While not explicitly limited to PV guests, this is PV-only by virtue of its
position in the pagefault handler.
Looking though the XenServer templates, this was used to work around bugs in
the 32bit RHEL/CentOS 4.{5..7} kernels (fixed in 4.8). RHEL 4 as a major
version when out if support in 2017.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
---
CC: Jan Beulich <JBeulich@suse.com>
CC: Wei Liu <wl@xen.org>
CC: Roger Pau Monné <roger.pau@citrix.com>
CC: Ian Jackson <Ian.Jackson@citrix.com>
CC: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
CC: Daniel De Graaf <dgdegra@tycho.nsa.gov>
---
tools/libxc/include/xenctrl.h | 3 ---
tools/libxc/xc_domain.c | 12 ------------
tools/python/xen/lowlevel/xc/xc.c | 22 ----------------------
xen/arch/x86/domctl.c | 4 ----
xen/arch/x86/traps.c | 14 --------------
xen/include/asm-x86/domain.h | 3 ---
xen/include/public/domctl.h | 7 +------
xen/xsm/flask/hooks.c | 1 -
xen/xsm/flask/policy/access_vectors | 3 +--
9 files changed, 2 insertions(+), 67 deletions(-)
diff --git a/tools/libxc/include/xenctrl.h b/tools/libxc/include/xenctrl.h
index 0ff6ed9e70..a36896034a 100644
--- a/tools/libxc/include/xenctrl.h
+++ b/tools/libxc/include/xenctrl.h
@@ -1787,9 +1787,6 @@ int xc_domain_set_machine_address_size(xc_interface *xch,
int xc_domain_get_machine_address_size(xc_interface *xch,
uint32_t domid);
-int xc_domain_suppress_spurious_page_faults(xc_interface *xch,
- uint32_t domid);
-
/* Set the target domain */
int xc_domain_set_target(xc_interface *xch,
uint32_t domid,
diff --git a/tools/libxc/xc_domain.c b/tools/libxc/xc_domain.c
index 05d771f2ce..64ca513aae 100644
--- a/tools/libxc/xc_domain.c
+++ b/tools/libxc/xc_domain.c
@@ -2190,18 +2190,6 @@ int xc_domain_get_machine_address_size(xc_interface *xch, uint32_t domid)
return rc == 0 ? domctl.u.address_size.size : rc;
}
-int xc_domain_suppress_spurious_page_faults(xc_interface *xc, uint32_t domid)
-{
- DECLARE_DOMCTL;
-
- memset(&domctl, 0, sizeof(domctl));
- domctl.domain = domid;
- domctl.cmd = XEN_DOMCTL_suppress_spurious_page_faults;
-
- return do_domctl(xc, &domctl);
-
-}
-
int xc_domain_debug_control(xc_interface *xc, uint32_t domid, uint32_t sop, uint32_t vcpu)
{
DECLARE_DOMCTL;
diff --git a/tools/python/xen/lowlevel/xc/xc.c b/tools/python/xen/lowlevel/xc/xc.c
index 188bfa34da..7e831a26a7 100644
--- a/tools/python/xen/lowlevel/xc/xc.c
+++ b/tools/python/xen/lowlevel/xc/xc.c
@@ -786,22 +786,6 @@ static PyObject *pyxc_dom_set_machine_address_size(XcObject *self,
Py_INCREF(zero);
return zero;
}
-
-static PyObject *pyxc_dom_suppress_spurious_page_faults(XcObject *self,
- PyObject *args,
- PyObject *kwds)
-{
- uint32_t dom;
-
- if (!PyArg_ParseTuple(args, "i", &dom))
- return NULL;
-
- if (xc_domain_suppress_spurious_page_faults(self->xc_handle, dom) != 0)
- return pyxc_error_to_exception(self->xc_handle);
-
- Py_INCREF(zero);
- return zero;
-}
#endif /* __i386__ || __x86_64__ */
static PyObject *pyxc_gnttab_hvm_seed(XcObject *self,
@@ -2436,12 +2420,6 @@ static PyMethodDef pyxc_methods[] = {
"Set maximum machine address size for this domain.\n"
" dom [int]: Identifier of domain.\n"
" width [int]: Maximum machine address width.\n" },
-
- { "domain_suppress_spurious_page_faults",
- (PyCFunction)pyxc_dom_suppress_spurious_page_faults,
- METH_VARARGS, "\n"
- "Do not propagate spurious page faults to this guest.\n"
- " dom [int]: Identifier of domain.\n" },
#endif
{ "dom_set_memshr",
diff --git a/xen/arch/x86/domctl.c b/xen/arch/x86/domctl.c
index 2d45e5b8a8..34a6f88b8a 100644
--- a/xen/arch/x86/domctl.c
+++ b/xen/arch/x86/domctl.c
@@ -988,10 +988,6 @@ long arch_do_domctl(
}
break;
- case XEN_DOMCTL_suppress_spurious_page_faults:
- d->arch.suppress_spurious_page_faults = 1;
- break;
-
#ifdef CONFIG_HVM
case XEN_DOMCTL_debug_op:
{
diff --git a/xen/arch/x86/traps.c b/xen/arch/x86/traps.c
index 23069e25ec..350903add5 100644
--- a/xen/arch/x86/traps.c
+++ b/xen/arch/x86/traps.c
@@ -1452,20 +1452,6 @@ void do_page_fault(struct cpu_user_regs *regs)
error_code, _p(addr));
}
- if ( unlikely(current->domain->arch.suppress_spurious_page_faults) )
- {
- pf_type = spurious_page_fault(addr, regs);
- if ( (pf_type == smep_fault) || (pf_type == smap_fault))
- {
- printk(XENLOG_G_ERR "%pv fatal SM%cP violation\n",
- current, (pf_type == smep_fault) ? 'E' : 'A');
-
- domain_crash(current->domain);
- }
- if ( pf_type != real_fault )
- return;
- }
-
if ( unlikely(regs->error_code & PFEC_reserved_bit) )
reserved_bit_page_fault(addr, regs);
diff --git a/xen/include/asm-x86/domain.h b/xen/include/asm-x86/domain.h
index 933b85901f..8523c3f5e0 100644
--- a/xen/include/asm-x86/domain.h
+++ b/xen/include/asm-x86/domain.h
@@ -339,9 +339,6 @@ struct arch_domain
/* Is shared-info page in 32-bit format? */
bool_t has_32bit_shinfo;
- /* Domain cannot handle spurious page faults? */
- bool_t suppress_spurious_page_faults;
-
/* Is PHYSDEVOP_eoi to automatically unmask the event channel? */
bool_t auto_unmask;
diff --git a/xen/include/public/domctl.h b/xen/include/public/domctl.h
index 19486d5e32..726ce675e8 100644
--- a/xen/include/public/domctl.h
+++ b/xen/include/public/domctl.h
@@ -698,11 +698,6 @@ struct xen_domctl_subscribe {
/* XEN_DOMCTL_set_machine_address_size */
/* XEN_DOMCTL_get_machine_address_size */
-/*
- * Do not inject spurious page faults into this domain.
- */
-/* XEN_DOMCTL_suppress_spurious_page_faults */
-
/* XEN_DOMCTL_debug_op */
#define XEN_DOMCTL_DEBUG_OP_SINGLE_STEP_OFF 0
#define XEN_DOMCTL_DEBUG_OP_SINGLE_STEP_ON 1
@@ -1172,7 +1167,7 @@ struct xen_domctl {
#define XEN_DOMCTL_get_device_group 50
#define XEN_DOMCTL_set_machine_address_size 51
#define XEN_DOMCTL_get_machine_address_size 52
-#define XEN_DOMCTL_suppress_spurious_page_faults 53
+/* #define XEN_DOMCTL_suppress_spurious_page_faults 53 - Obsolete */
#define XEN_DOMCTL_debug_op 54
#define XEN_DOMCTL_gethvmcontext_partial 55
#define XEN_DOMCTL_vm_event_op 56
diff --git a/xen/xsm/flask/hooks.c b/xen/xsm/flask/hooks.c
index 791c1f66af..fd5ec992cf 100644
--- a/xen/xsm/flask/hooks.c
+++ b/xen/xsm/flask/hooks.c
@@ -712,7 +712,6 @@ static int flask_domctl(struct domain *d, int cmd)
case XEN_DOMCTL_subscribe:
case XEN_DOMCTL_disable_migrate:
- case XEN_DOMCTL_suppress_spurious_page_faults:
return current_has_perm(d, SECCLASS_DOMAIN, DOMAIN__SET_MISC_INFO);
case XEN_DOMCTL_set_virq_handler:
diff --git a/xen/xsm/flask/policy/access_vectors b/xen/xsm/flask/policy/access_vectors
index 194d743a71..c9ebd0f37e 100644
--- a/xen/xsm/flask/policy/access_vectors
+++ b/xen/xsm/flask/policy/access_vectors
@@ -176,8 +176,7 @@ class domain
getpodtarget
# XENMEM_set_pod_target
setpodtarget
-# XEN_DOMCTL_subscribe, XEN_DOMCTL_disable_migrate,
-# XEN_DOMCTL_suppress_spurious_page_faults
+# XEN_DOMCTL_subscribe, XEN_DOMCTL_disable_migrate
set_misc_info
# XEN_DOMCTL_set_virq_handler
set_virq_handler
--
2.11.0
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xenproject.org
https://lists.xenproject.org/mailman/listinfo/xen-develOn Tue, Aug 13, 2019 at 11:53:51AM +0100, Andrew Cooper wrote:
> This functionality is obsolete. It was introduced by c/s 39407bed9c0 into
> Xend, but never exposed in libxl.
>
> While not explicitly limited to PV guests, this is PV-only by virtue of its
> position in the pagefault handler.
>
> Looking though the XenServer templates, this was used to work around bugs in
> the 32bit RHEL/CentOS 4.{5..7} kernels (fixed in 4.8). RHEL 4 as a major
> version when out if support in 2017.
>
> Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Python part:
Acked-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Also, I confirm it isn't used in Qubes OS.
> ---
> CC: Jan Beulich <JBeulich@suse.com>
> CC: Wei Liu <wl@xen.org>
> CC: Roger Pau Monné <roger.pau@citrix.com>
> CC: Ian Jackson <Ian.Jackson@citrix.com>
> CC: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
> CC: Daniel De Graaf <dgdegra@tycho.nsa.gov>
> ---
> tools/libxc/include/xenctrl.h | 3 ---
> tools/libxc/xc_domain.c | 12 ------------
> tools/python/xen/lowlevel/xc/xc.c | 22 ----------------------
> xen/arch/x86/domctl.c | 4 ----
> xen/arch/x86/traps.c | 14 --------------
> xen/include/asm-x86/domain.h | 3 ---
> xen/include/public/domctl.h | 7 +------
> xen/xsm/flask/hooks.c | 1 -
> xen/xsm/flask/policy/access_vectors | 3 +--
> 9 files changed, 2 insertions(+), 67 deletions(-)
>
> diff --git a/tools/libxc/include/xenctrl.h b/tools/libxc/include/xenctrl.h
> index 0ff6ed9e70..a36896034a 100644
> --- a/tools/libxc/include/xenctrl.h
> +++ b/tools/libxc/include/xenctrl.h
> @@ -1787,9 +1787,6 @@ int xc_domain_set_machine_address_size(xc_interface *xch,
> int xc_domain_get_machine_address_size(xc_interface *xch,
> uint32_t domid);
>
> -int xc_domain_suppress_spurious_page_faults(xc_interface *xch,
> - uint32_t domid);
> -
> /* Set the target domain */
> int xc_domain_set_target(xc_interface *xch,
> uint32_t domid,
> diff --git a/tools/libxc/xc_domain.c b/tools/libxc/xc_domain.c
> index 05d771f2ce..64ca513aae 100644
> --- a/tools/libxc/xc_domain.c
> +++ b/tools/libxc/xc_domain.c
> @@ -2190,18 +2190,6 @@ int xc_domain_get_machine_address_size(xc_interface *xch, uint32_t domid)
> return rc == 0 ? domctl.u.address_size.size : rc;
> }
>
> -int xc_domain_suppress_spurious_page_faults(xc_interface *xc, uint32_t domid)
> -{
> - DECLARE_DOMCTL;
> -
> - memset(&domctl, 0, sizeof(domctl));
> - domctl.domain = domid;
> - domctl.cmd = XEN_DOMCTL_suppress_spurious_page_faults;
> -
> - return do_domctl(xc, &domctl);
> -
> -}
> -
> int xc_domain_debug_control(xc_interface *xc, uint32_t domid, uint32_t sop, uint32_t vcpu)
> {
> DECLARE_DOMCTL;
> diff --git a/tools/python/xen/lowlevel/xc/xc.c b/tools/python/xen/lowlevel/xc/xc.c
> index 188bfa34da..7e831a26a7 100644
> --- a/tools/python/xen/lowlevel/xc/xc.c
> +++ b/tools/python/xen/lowlevel/xc/xc.c
> @@ -786,22 +786,6 @@ static PyObject *pyxc_dom_set_machine_address_size(XcObject *self,
> Py_INCREF(zero);
> return zero;
> }
> -
> -static PyObject *pyxc_dom_suppress_spurious_page_faults(XcObject *self,
> - PyObject *args,
> - PyObject *kwds)
> -{
> - uint32_t dom;
> -
> - if (!PyArg_ParseTuple(args, "i", &dom))
> - return NULL;
> -
> - if (xc_domain_suppress_spurious_page_faults(self->xc_handle, dom) != 0)
> - return pyxc_error_to_exception(self->xc_handle);
> -
> - Py_INCREF(zero);
> - return zero;
> -}
> #endif /* __i386__ || __x86_64__ */
>
> static PyObject *pyxc_gnttab_hvm_seed(XcObject *self,
> @@ -2436,12 +2420,6 @@ static PyMethodDef pyxc_methods[] = {
> "Set maximum machine address size for this domain.\n"
> " dom [int]: Identifier of domain.\n"
> " width [int]: Maximum machine address width.\n" },
> -
> - { "domain_suppress_spurious_page_faults",
> - (PyCFunction)pyxc_dom_suppress_spurious_page_faults,
> - METH_VARARGS, "\n"
> - "Do not propagate spurious page faults to this guest.\n"
> - " dom [int]: Identifier of domain.\n" },
> #endif
>
> { "dom_set_memshr",
> diff --git a/xen/arch/x86/domctl.c b/xen/arch/x86/domctl.c
> index 2d45e5b8a8..34a6f88b8a 100644
> --- a/xen/arch/x86/domctl.c
> +++ b/xen/arch/x86/domctl.c
> @@ -988,10 +988,6 @@ long arch_do_domctl(
> }
> break;
>
> - case XEN_DOMCTL_suppress_spurious_page_faults:
> - d->arch.suppress_spurious_page_faults = 1;
> - break;
> -
> #ifdef CONFIG_HVM
> case XEN_DOMCTL_debug_op:
> {
> diff --git a/xen/arch/x86/traps.c b/xen/arch/x86/traps.c
> index 23069e25ec..350903add5 100644
> --- a/xen/arch/x86/traps.c
> +++ b/xen/arch/x86/traps.c
> @@ -1452,20 +1452,6 @@ void do_page_fault(struct cpu_user_regs *regs)
> error_code, _p(addr));
> }
>
> - if ( unlikely(current->domain->arch.suppress_spurious_page_faults) )
> - {
> - pf_type = spurious_page_fault(addr, regs);
> - if ( (pf_type == smep_fault) || (pf_type == smap_fault))
> - {
> - printk(XENLOG_G_ERR "%pv fatal SM%cP violation\n",
> - current, (pf_type == smep_fault) ? 'E' : 'A');
> -
> - domain_crash(current->domain);
> - }
> - if ( pf_type != real_fault )
> - return;
> - }
> -
> if ( unlikely(regs->error_code & PFEC_reserved_bit) )
> reserved_bit_page_fault(addr, regs);
>
> diff --git a/xen/include/asm-x86/domain.h b/xen/include/asm-x86/domain.h
> index 933b85901f..8523c3f5e0 100644
> --- a/xen/include/asm-x86/domain.h
> +++ b/xen/include/asm-x86/domain.h
> @@ -339,9 +339,6 @@ struct arch_domain
> /* Is shared-info page in 32-bit format? */
> bool_t has_32bit_shinfo;
>
> - /* Domain cannot handle spurious page faults? */
> - bool_t suppress_spurious_page_faults;
> -
> /* Is PHYSDEVOP_eoi to automatically unmask the event channel? */
> bool_t auto_unmask;
>
> diff --git a/xen/include/public/domctl.h b/xen/include/public/domctl.h
> index 19486d5e32..726ce675e8 100644
> --- a/xen/include/public/domctl.h
> +++ b/xen/include/public/domctl.h
> @@ -698,11 +698,6 @@ struct xen_domctl_subscribe {
> /* XEN_DOMCTL_set_machine_address_size */
> /* XEN_DOMCTL_get_machine_address_size */
>
> -/*
> - * Do not inject spurious page faults into this domain.
> - */
> -/* XEN_DOMCTL_suppress_spurious_page_faults */
> -
> /* XEN_DOMCTL_debug_op */
> #define XEN_DOMCTL_DEBUG_OP_SINGLE_STEP_OFF 0
> #define XEN_DOMCTL_DEBUG_OP_SINGLE_STEP_ON 1
> @@ -1172,7 +1167,7 @@ struct xen_domctl {
> #define XEN_DOMCTL_get_device_group 50
> #define XEN_DOMCTL_set_machine_address_size 51
> #define XEN_DOMCTL_get_machine_address_size 52
> -#define XEN_DOMCTL_suppress_spurious_page_faults 53
> +/* #define XEN_DOMCTL_suppress_spurious_page_faults 53 - Obsolete */
> #define XEN_DOMCTL_debug_op 54
> #define XEN_DOMCTL_gethvmcontext_partial 55
> #define XEN_DOMCTL_vm_event_op 56
> diff --git a/xen/xsm/flask/hooks.c b/xen/xsm/flask/hooks.c
> index 791c1f66af..fd5ec992cf 100644
> --- a/xen/xsm/flask/hooks.c
> +++ b/xen/xsm/flask/hooks.c
> @@ -712,7 +712,6 @@ static int flask_domctl(struct domain *d, int cmd)
>
> case XEN_DOMCTL_subscribe:
> case XEN_DOMCTL_disable_migrate:
> - case XEN_DOMCTL_suppress_spurious_page_faults:
> return current_has_perm(d, SECCLASS_DOMAIN, DOMAIN__SET_MISC_INFO);
>
> case XEN_DOMCTL_set_virq_handler:
> diff --git a/xen/xsm/flask/policy/access_vectors b/xen/xsm/flask/policy/access_vectors
> index 194d743a71..c9ebd0f37e 100644
> --- a/xen/xsm/flask/policy/access_vectors
> +++ b/xen/xsm/flask/policy/access_vectors
> @@ -176,8 +176,7 @@ class domain
> getpodtarget
> # XENMEM_set_pod_target
> setpodtarget
> -# XEN_DOMCTL_subscribe, XEN_DOMCTL_disable_migrate,
> -# XEN_DOMCTL_suppress_spurious_page_faults
> +# XEN_DOMCTL_subscribe, XEN_DOMCTL_disable_migrate
> set_misc_info
> # XEN_DOMCTL_set_virq_handler
> set_virq_handler
--
Best Regards,
Marek Marczykowski-Górecki
Invisible Things Lab
A: Because it messes up the order in which people normally read text.
Q: Why is top-posting such a bad thing?
_______________________________________________
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On 13.08.2019 12:53, Andrew Cooper wrote:
> This functionality is obsolete. It was introduced by c/s 39407bed9c0 into
> Xend, but never exposed in libxl.
This is good enough a reason I think (hope), while ...
> While not explicitly limited to PV guests, this is PV-only by virtue of its
> position in the pagefault handler.
>
> Looking though the XenServer templates, this was used to work around bugs in
> the 32bit RHEL/CentOS 4.{5..7} kernels (fixed in 4.8). RHEL 4 as a major
> version when out if support in 2017.
... I wouldn't accept this as justification, since people are
free to use out-of-support software for as long as they wish.
> Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Hypervisor parts
Reviewed-by: Jan Beulich <jbeulich@suse.com>
with one further suggestion:
> --- a/xen/arch/x86/traps.c
> +++ b/xen/arch/x86/traps.c
> @@ -1452,20 +1452,6 @@ void do_page_fault(struct cpu_user_regs *regs)
> error_code, _p(addr));
> }
>
> - if ( unlikely(current->domain->arch.suppress_spurious_page_faults) )
> - {
> - pf_type = spurious_page_fault(addr, regs);
> - if ( (pf_type == smep_fault) || (pf_type == smap_fault))
> - {
> - printk(XENLOG_G_ERR "%pv fatal SM%cP violation\n",
> - current, (pf_type == smep_fault) ? 'E' : 'A');
> -
> - domain_crash(current->domain);
> - }
> - if ( pf_type != real_fault )
> - return;
> - }
You may want to consider reducing pf_type's scope at the same
time.
Jan
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On 27/08/2019 16:39, Jan Beulich wrote:
> On 13.08.2019 12:53, Andrew Cooper wrote:
>> This functionality is obsolete. It was introduced by c/s 39407bed9c0
>> into
>> Xend, but never exposed in libxl.
>
> This is good enough a reason I think (hope), while ...
>
>> While not explicitly limited to PV guests, this is PV-only by virtue
>> of its
>> position in the pagefault handler.
>>
>> Looking though the XenServer templates, this was used to work around
>> bugs in
>> the 32bit RHEL/CentOS 4.{5..7} kernels (fixed in 4.8). RHEL 4 as a
>> major
>> version when out if support in 2017.
>
> ... I wouldn't accept this as justification,
I'd be approaching this differently if support were in libxl, but...
> since people are
> free to use out-of-support software for as long as they wish.
... there are a lot of very good reasons not to keep on using
out-of-support software. A recent example is the WannaCry outbreak
which spread in part due to the still-prolific use of Windows XP.
Furthermore, people running kernels which are that obsolete will also be
running similarly-obsolete versions of Xen, so this change isn't going
to affect them.
>
>> Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
>
> Hypervisor parts
> Reviewed-by: Jan Beulich <jbeulich@suse.com>
Thanks,
> with one further suggestion:
>
>> --- a/xen/arch/x86/traps.c
>> +++ b/xen/arch/x86/traps.c
>> @@ -1452,20 +1452,6 @@ void do_page_fault(struct cpu_user_regs *regs)
>> error_code, _p(addr));
>> }
>> - if (
>> unlikely(current->domain->arch.suppress_spurious_page_faults) )
>> - {
>> - pf_type = spurious_page_fault(addr, regs);
>> - if ( (pf_type == smep_fault) || (pf_type == smap_fault))
>> - {
>> - printk(XENLOG_G_ERR "%pv fatal SM%cP violation\n",
>> - current, (pf_type == smep_fault) ? 'E' : 'A');
>> -
>> - domain_crash(current->domain);
>> - }
>> - if ( pf_type != real_fault )
>> - return;
>> - }
>
> You may want to consider reducing pf_type's scope at the same
> time.
This isn't too much of a change, so I've included it.
~Andrew
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