| Message ID | 20200108140810.6528-2-aisaila@bitdefender.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [V7,1/4] x86/mm: Add array_index_nospec to guest provided index values | expand |
On 08.01.2020 15:08, Alexandru Stefan ISAILA wrote: > By default the sve bits are not set. > This patch adds a new hypercall, xc_altp2m_set_supress_ve_multi(), > to set a range of sve bits. > The core function, p2m_set_suppress_ve_multi(), does not break in case > of a error and it is doing a best effort for setting the bits in the > given range. A check for continuation is made in order to have > preemption on large ranges. > The gfn of the first error is stored in > xen_hvm_altp2m_suppress_ve_multi.first_error and the error code is > stored in xen_hvm_altp2m_suppress_ve_multi.first_error_code. > If no error occurred the values will be 0. These last two sentences must have been stale for a while. IOW ... > Changes since V6: > - Fix commit message ... has this really happened? > --- a/xen/arch/x86/mm/p2m.c > +++ b/xen/arch/x86/mm/p2m.c > @@ -3030,45 +3030,87 @@ out: > */ > int p2m_set_suppress_ve(struct domain *d, gfn_t gfn, bool suppress_ve, > unsigned int altp2m_idx) > +{ > + int rc; > + struct xen_hvm_altp2m_suppress_ve_multi sve = {0}; > + > + sve.view = altp2m_idx; > + sve.suppress_ve = suppress_ve; > + sve.first_gfn = gfn_x(gfn); > + sve.last_gfn = gfn_x(gfn); Can't all of these move into the initializer, instead of the somewhat odd 0? > + if ( !(rc = p2m_set_suppress_ve_multi(d, &sve)) && sve.first_error ) > + rc = sve.first_error; Why the right side of the && ? > +/* > + * Set/clear the #VE suppress bit for multiple pages. Only available on VMX. > + */ > +int p2m_set_suppress_ve_multi(struct domain *d, > + struct xen_hvm_altp2m_suppress_ve_multi *sve) > { > struct p2m_domain *host_p2m = p2m_get_hostp2m(d); > struct p2m_domain *ap2m = NULL; > - struct p2m_domain *p2m; > - mfn_t mfn; > - p2m_access_t a; > - p2m_type_t t; > - int rc; > + struct p2m_domain *p2m = host_p2m; > + uint64_t start = sve->first_gfn; > + int rc = 0; > > - if ( altp2m_idx > 0 ) > + if ( sve->view > 0 ) > { > - if ( altp2m_idx >= min(ARRAY_SIZE(d->arch.altp2m_p2m), MAX_EPTP) || > - d->arch.altp2m_eptp[array_index_nospec(altp2m_idx, MAX_EPTP)] == > + if ( sve->view >= min(ARRAY_SIZE(d->arch.altp2m_p2m), MAX_EPTP) || > + d->arch.altp2m_eptp[array_index_nospec(sve->view, MAX_EPTP)] == > mfn_x(INVALID_MFN) ) > return -EINVAL; > > - p2m = ap2m = d->arch.altp2m_p2m[array_index_nospec(altp2m_idx, > + p2m = ap2m = d->arch.altp2m_p2m[array_index_nospec(sve->view, > ARRAY_SIZE(d->arch.altp2m_p2m))]; > } > - else > - p2m = host_p2m; > > - gfn_lock(host_p2m, gfn, 0); > + p2m_lock(host_p2m); > > if ( ap2m ) > p2m_lock(ap2m); > > - rc = altp2m_get_effective_entry(p2m, gfn, &mfn, &t, &a, AP2MGET_query); > + while ( sve->last_gfn >= start ) > + { > + p2m_access_t a; > + p2m_type_t t; > + mfn_t mfn; > + int err = 0; > > - if ( rc ) > - goto out; > + if ( (err = altp2m_get_effective_entry(p2m, _gfn(start), &mfn, &t, &a, > + AP2MGET_query)) && > + !sve->first_error ) > + { > + sve->first_error_gfn = start; /* Save the gfn of the first error */ > + sve->first_error = err; /* Save the first error code */ > + } > > - rc = p2m->set_entry(p2m, gfn, mfn, PAGE_ORDER_4K, t, a, suppress_ve); > + if ( !err && (err = p2m->set_entry(p2m, _gfn(start), mfn, > + PAGE_ORDER_4K, t, a, > + sve->suppress_ve)) && > + !sve->first_error ) > + { > + sve->first_error_gfn = start; /* Save the gfn of the first error */ > + sve->first_error = err; /* Save the first error code */ > + } I think it would help readability if you didn't do this error saving twice. Jan
On 10.01.2020 18:20, Jan Beulich wrote: > On 08.01.2020 15:08, Alexandru Stefan ISAILA wrote: >> By default the sve bits are not set. >> This patch adds a new hypercall, xc_altp2m_set_supress_ve_multi(), >> to set a range of sve bits. >> The core function, p2m_set_suppress_ve_multi(), does not break in case >> of a error and it is doing a best effort for setting the bits in the >> given range. A check for continuation is made in order to have >> preemption on large ranges. >> The gfn of the first error is stored in >> xen_hvm_altp2m_suppress_ve_multi.first_error and the error code is >> stored in xen_hvm_altp2m_suppress_ve_multi.first_error_code. >> If no error occurred the values will be 0. > > These last two sentences must have been stale for a while. IOW ... I just saw that now, yes you are right, from when I changed the field names. > >> Changes since V6: >> - Fix commit message > > ... has this really happened? This was done for the "braek" typo and for large/big ranges but I will fix the field names as well, thanks for pointing that out. > >> --- a/xen/arch/x86/mm/p2m.c >> +++ b/xen/arch/x86/mm/p2m.c >> @@ -3030,45 +3030,87 @@ out: >> */ >> int p2m_set_suppress_ve(struct domain *d, gfn_t gfn, bool suppress_ve, >> unsigned int altp2m_idx) >> +{ >> + int rc; >> + struct xen_hvm_altp2m_suppress_ve_multi sve = {0}; >> + >> + sve.view = altp2m_idx; >> + sve.suppress_ve = suppress_ve; >> + sve.first_gfn = gfn_x(gfn); >> + sve.last_gfn = gfn_x(gfn); > > Can't all of these move into the initializer, instead of the > somewhat odd 0? Sure, it's no trouble. > >> + if ( !(rc = p2m_set_suppress_ve_multi(d, &sve)) && sve.first_error ) >> + rc = sve.first_error; > > Why the right side of the && ? This is intended to have p2m_set_suppress_ve() call p2m_set_suppress_ve_multi(). So here first I call the _multi version and the check if there was any error from the set/get (that is what p2m_set_suppress_ve did before). I don't know why git made the patch so ugly. > >> +/* >> + * Set/clear the #VE suppress bit for multiple pages. Only available on VMX. >> + */ >> +int p2m_set_suppress_ve_multi(struct domain *d, >> + struct xen_hvm_altp2m_suppress_ve_multi *sve) >> { >> struct p2m_domain *host_p2m = p2m_get_hostp2m(d); >> struct p2m_domain *ap2m = NULL; >> - struct p2m_domain *p2m; >> - mfn_t mfn; >> - p2m_access_t a; >> - p2m_type_t t; >> - int rc; >> + struct p2m_domain *p2m = host_p2m; >> + uint64_t start = sve->first_gfn; >> + int rc = 0; >> >> - if ( altp2m_idx > 0 ) >> + if ( sve->view > 0 ) >> { >> - if ( altp2m_idx >= min(ARRAY_SIZE(d->arch.altp2m_p2m), MAX_EPTP) || >> - d->arch.altp2m_eptp[array_index_nospec(altp2m_idx, MAX_EPTP)] == >> + if ( sve->view >= min(ARRAY_SIZE(d->arch.altp2m_p2m), MAX_EPTP) || >> + d->arch.altp2m_eptp[array_index_nospec(sve->view, MAX_EPTP)] == >> mfn_x(INVALID_MFN) ) >> return -EINVAL; >> >> - p2m = ap2m = d->arch.altp2m_p2m[array_index_nospec(altp2m_idx, >> + p2m = ap2m = d->arch.altp2m_p2m[array_index_nospec(sve->view, >> ARRAY_SIZE(d->arch.altp2m_p2m))]; >> } >> - else >> - p2m = host_p2m; >> >> - gfn_lock(host_p2m, gfn, 0); >> + p2m_lock(host_p2m); >> >> if ( ap2m ) >> p2m_lock(ap2m); >> >> - rc = altp2m_get_effective_entry(p2m, gfn, &mfn, &t, &a, AP2MGET_query); >> + while ( sve->last_gfn >= start ) >> + { >> + p2m_access_t a; >> + p2m_type_t t; >> + mfn_t mfn; >> + int err = 0; >> >> - if ( rc ) >> - goto out; >> + if ( (err = altp2m_get_effective_entry(p2m, _gfn(start), &mfn, &t, &a, >> + AP2MGET_query)) && >> + !sve->first_error ) >> + { >> + sve->first_error_gfn = start; /* Save the gfn of the first error */ >> + sve->first_error = err; /* Save the first error code */ >> + } >> >> - rc = p2m->set_entry(p2m, gfn, mfn, PAGE_ORDER_4K, t, a, suppress_ve); >> + if ( !err && (err = p2m->set_entry(p2m, _gfn(start), mfn, >> + PAGE_ORDER_4K, t, a, >> + sve->suppress_ve)) && >> + !sve->first_error ) >> + { >> + sve->first_error_gfn = start; /* Save the gfn of the first error */ >> + sve->first_error = err; /* Save the first error code */ >> + } > > I think it would help readability if you didn't do this error > saving twice. > George requested this as well as having the single version call the _multi version. Alex
On 13.01.2020 11:32, Alexandru Stefan ISAILA wrote: > On 10.01.2020 18:20, Jan Beulich wrote: >> On 08.01.2020 15:08, Alexandru Stefan ISAILA wrote: >>> + if ( !(rc = p2m_set_suppress_ve_multi(d, &sve)) && sve.first_error ) >>> + rc = sve.first_error; >> >> Why the right side of the && ? > > This is intended to have p2m_set_suppress_ve() call > p2m_set_suppress_ve_multi(). So here first I call the _multi version and > the check if there was any error from the set/get (that is what > p2m_set_suppress_ve did before). To put my original question differently: from a functionality pov, how would if ( !(rc = p2m_set_suppress_ve_multi(d, &sve)) ) rc = sve.first_error; be different from your variant (as long as the field indeed starts out as zero)? > I don't know why git made the patch so ugly. I have no idea what ugliness you refer to here. Jan
On 13.01.2020 14:53, Jan Beulich wrote: > On 13.01.2020 11:32, Alexandru Stefan ISAILA wrote: >> On 10.01.2020 18:20, Jan Beulich wrote: >>> On 08.01.2020 15:08, Alexandru Stefan ISAILA wrote: >>>> + if ( !(rc = p2m_set_suppress_ve_multi(d, &sve)) && sve.first_error ) >>>> + rc = sve.first_error; >>> >>> Why the right side of the && ? >> >> This is intended to have p2m_set_suppress_ve() call >> p2m_set_suppress_ve_multi(). So here first I call the _multi version and >> the check if there was any error from the set/get (that is what >> p2m_set_suppress_ve did before). > > To put my original question differently: from a functionality pov, > how would > > if ( !(rc = p2m_set_suppress_ve_multi(d, &sve)) ) > rc = sve.first_error; > > be different from your variant (as long as the field indeed starts > out as zero)? It will be the same in this case and it can be dropped. > >> I don't know why git made the patch so ugly. > > I have no idea what ugliness you refer to here. > I was talking about the fact that the changes in p2m_set_suppress_ve() got mixed with the ones in p2m_set_suppress_ve_multi().
diff --git a/tools/libxc/include/xenctrl.h b/tools/libxc/include/xenctrl.h index 75f191ae3a..cc4eb1e3d3 100644 --- a/tools/libxc/include/xenctrl.h +++ b/tools/libxc/include/xenctrl.h @@ -1923,6 +1923,10 @@ int xc_altp2m_switch_to_view(xc_interface *handle, uint32_t domid, uint16_t view_id); int xc_altp2m_set_suppress_ve(xc_interface *handle, uint32_t domid, uint16_t view_id, xen_pfn_t gfn, bool sve); +int xc_altp2m_set_supress_ve_multi(xc_interface *handle, uint32_t domid, + uint16_t view_id, xen_pfn_t first_gfn, + xen_pfn_t last_gfn, bool sve, + xen_pfn_t *error_gfn, int32_t *error_code); int xc_altp2m_get_suppress_ve(xc_interface *handle, uint32_t domid, uint16_t view_id, xen_pfn_t gfn, bool *sve); int xc_altp2m_set_mem_access(xc_interface *handle, uint32_t domid, diff --git a/tools/libxc/xc_altp2m.c b/tools/libxc/xc_altp2m.c index 09dad0355e..46fb725806 100644 --- a/tools/libxc/xc_altp2m.c +++ b/tools/libxc/xc_altp2m.c @@ -234,6 +234,39 @@ int xc_altp2m_set_suppress_ve(xc_interface *handle, uint32_t domid, return rc; } +int xc_altp2m_set_supress_ve_multi(xc_interface *handle, uint32_t domid, + uint16_t view_id, xen_pfn_t first_gfn, + xen_pfn_t last_gfn, bool sve, + xen_pfn_t *error_gfn, int32_t *error_code) +{ + int rc; + DECLARE_HYPERCALL_BUFFER(xen_hvm_altp2m_op_t, arg); + + arg = xc_hypercall_buffer_alloc(handle, arg, sizeof(*arg)); + if ( arg == NULL ) + return -1; + + arg->version = HVMOP_ALTP2M_INTERFACE_VERSION; + arg->cmd = HVMOP_altp2m_set_suppress_ve_multi; + arg->domain = domid; + arg->u.suppress_ve_multi.view = view_id; + arg->u.suppress_ve_multi.first_gfn = first_gfn; + arg->u.suppress_ve_multi.last_gfn = last_gfn; + arg->u.suppress_ve_multi.suppress_ve = sve; + + rc = xencall2(handle->xcall, __HYPERVISOR_hvm_op, HVMOP_altp2m, + HYPERCALL_BUFFER_AS_ARG(arg)); + + if ( arg->u.suppress_ve_multi.first_error ) + { + *error_gfn = arg->u.suppress_ve_multi.first_error_gfn; + *error_code = arg->u.suppress_ve_multi.first_error; + } + + xc_hypercall_buffer_free(handle, arg); + return rc; +} + int xc_altp2m_set_mem_access(xc_interface *handle, uint32_t domid, uint16_t view_id, xen_pfn_t gfn, xenmem_access_t access) diff --git a/xen/arch/x86/hvm/hvm.c b/xen/arch/x86/hvm/hvm.c index 4723f5d09c..4d79b4934e 100644 --- a/xen/arch/x86/hvm/hvm.c +++ b/xen/arch/x86/hvm/hvm.c @@ -4520,6 +4520,7 @@ static int do_altp2m_op( case HVMOP_altp2m_destroy_p2m: case HVMOP_altp2m_switch_p2m: case HVMOP_altp2m_set_suppress_ve: + case HVMOP_altp2m_set_suppress_ve_multi: case HVMOP_altp2m_get_suppress_ve: case HVMOP_altp2m_set_mem_access: case HVMOP_altp2m_set_mem_access_multi: @@ -4678,6 +4679,25 @@ static int do_altp2m_op( } break; + case HVMOP_altp2m_set_suppress_ve_multi: + { + uint64_t max_phys_addr = (1UL << d->arch.cpuid->extd.maxphysaddr) - 1; + + a.u.suppress_ve_multi.last_gfn = min(a.u.suppress_ve_multi.last_gfn, + max_phys_addr); + + if ( a.u.suppress_ve_multi.pad1 || + a.u.suppress_ve_multi.first_gfn > a.u.suppress_ve_multi.last_gfn ) + rc = -EINVAL; + else + { + rc = p2m_set_suppress_ve_multi(d, &a.u.suppress_ve_multi); + if ( (!rc || rc == -ERESTART) && __copy_to_guest(arg, &a, 1) ) + rc = -EFAULT; + } + break; + } + case HVMOP_altp2m_get_suppress_ve: if ( a.u.suppress_ve.pad1 || a.u.suppress_ve.pad2 ) rc = -EINVAL; diff --git a/xen/arch/x86/mm/p2m.c b/xen/arch/x86/mm/p2m.c index 5f046960a9..223ca0cf4c 100644 --- a/xen/arch/x86/mm/p2m.c +++ b/xen/arch/x86/mm/p2m.c @@ -3030,45 +3030,87 @@ out: */ int p2m_set_suppress_ve(struct domain *d, gfn_t gfn, bool suppress_ve, unsigned int altp2m_idx) +{ + int rc; + struct xen_hvm_altp2m_suppress_ve_multi sve = {0}; + + sve.view = altp2m_idx; + sve.suppress_ve = suppress_ve; + sve.first_gfn = gfn_x(gfn); + sve.last_gfn = gfn_x(gfn); + + if ( !(rc = p2m_set_suppress_ve_multi(d, &sve)) && sve.first_error ) + rc = sve.first_error; + + return rc; +} + +/* + * Set/clear the #VE suppress bit for multiple pages. Only available on VMX. + */ +int p2m_set_suppress_ve_multi(struct domain *d, + struct xen_hvm_altp2m_suppress_ve_multi *sve) { struct p2m_domain *host_p2m = p2m_get_hostp2m(d); struct p2m_domain *ap2m = NULL; - struct p2m_domain *p2m; - mfn_t mfn; - p2m_access_t a; - p2m_type_t t; - int rc; + struct p2m_domain *p2m = host_p2m; + uint64_t start = sve->first_gfn; + int rc = 0; - if ( altp2m_idx > 0 ) + if ( sve->view > 0 ) { - if ( altp2m_idx >= min(ARRAY_SIZE(d->arch.altp2m_p2m), MAX_EPTP) || - d->arch.altp2m_eptp[array_index_nospec(altp2m_idx, MAX_EPTP)] == + if ( sve->view >= min(ARRAY_SIZE(d->arch.altp2m_p2m), MAX_EPTP) || + d->arch.altp2m_eptp[array_index_nospec(sve->view, MAX_EPTP)] == mfn_x(INVALID_MFN) ) return -EINVAL; - p2m = ap2m = d->arch.altp2m_p2m[array_index_nospec(altp2m_idx, + p2m = ap2m = d->arch.altp2m_p2m[array_index_nospec(sve->view, ARRAY_SIZE(d->arch.altp2m_p2m))]; } - else - p2m = host_p2m; - gfn_lock(host_p2m, gfn, 0); + p2m_lock(host_p2m); if ( ap2m ) p2m_lock(ap2m); - rc = altp2m_get_effective_entry(p2m, gfn, &mfn, &t, &a, AP2MGET_query); + while ( sve->last_gfn >= start ) + { + p2m_access_t a; + p2m_type_t t; + mfn_t mfn; + int err = 0; - if ( rc ) - goto out; + if ( (err = altp2m_get_effective_entry(p2m, _gfn(start), &mfn, &t, &a, + AP2MGET_query)) && + !sve->first_error ) + { + sve->first_error_gfn = start; /* Save the gfn of the first error */ + sve->first_error = err; /* Save the first error code */ + } - rc = p2m->set_entry(p2m, gfn, mfn, PAGE_ORDER_4K, t, a, suppress_ve); + if ( !err && (err = p2m->set_entry(p2m, _gfn(start), mfn, + PAGE_ORDER_4K, t, a, + sve->suppress_ve)) && + !sve->first_error ) + { + sve->first_error_gfn = start; /* Save the gfn of the first error */ + sve->first_error = err; /* Save the first error code */ + } + + /* Check for continuation if it's not the last iteration. */ + if ( sve->last_gfn >= ++start && hypercall_preempt_check() ) + { + rc = -ERESTART; + break; + } + } + + sve->first_gfn = start; -out: if ( ap2m ) p2m_unlock(ap2m); - gfn_unlock(host_p2m, gfn, 0); + p2m_unlock(host_p2m); return rc; } diff --git a/xen/include/public/hvm/hvm_op.h b/xen/include/public/hvm/hvm_op.h index 353f8034d9..d344606864 100644 --- a/xen/include/public/hvm/hvm_op.h +++ b/xen/include/public/hvm/hvm_op.h @@ -46,6 +46,16 @@ struct xen_hvm_altp2m_suppress_ve { uint64_t gfn; }; +struct xen_hvm_altp2m_suppress_ve_multi { + uint16_t view; + uint8_t suppress_ve; /* Boolean type. */ + uint8_t pad1; + int32_t first_error; /* Should be set to 0. */ + uint64_t first_gfn; /* Value may be updated. */ + uint64_t last_gfn; + uint64_t first_error_gfn; /* Gfn of the first error. */ +}; + #if __XEN_INTERFACE_VERSION__ < 0x00040900 /* Set the logical level of one of a domain's PCI INTx wires. */ @@ -339,6 +349,8 @@ struct xen_hvm_altp2m_op { #define HVMOP_altp2m_vcpu_disable_notify 13 /* Get the active vcpu p2m index */ #define HVMOP_altp2m_get_p2m_idx 14 +/* Set the "Supress #VE" bit for a range of pages */ +#define HVMOP_altp2m_set_suppress_ve_multi 15 domid_t domain; uint16_t pad1; uint32_t pad2; @@ -353,6 +365,7 @@ struct xen_hvm_altp2m_op { struct xen_hvm_altp2m_change_gfn change_gfn; struct xen_hvm_altp2m_set_mem_access_multi set_mem_access_multi; struct xen_hvm_altp2m_suppress_ve suppress_ve; + struct xen_hvm_altp2m_suppress_ve_multi suppress_ve_multi; struct xen_hvm_altp2m_vcpu_disable_notify disable_notify; struct xen_hvm_altp2m_get_vcpu_p2m_idx get_vcpu_p2m_idx; uint8_t pad[64]; diff --git a/xen/include/xen/mem_access.h b/xen/include/xen/mem_access.h index e4d24502e0..00e594a0ad 100644 --- a/xen/include/xen/mem_access.h +++ b/xen/include/xen/mem_access.h @@ -75,6 +75,9 @@ long p2m_set_mem_access_multi(struct domain *d, int p2m_set_suppress_ve(struct domain *d, gfn_t gfn, bool suppress_ve, unsigned int altp2m_idx); +int p2m_set_suppress_ve_multi(struct domain *d, + struct xen_hvm_altp2m_suppress_ve_multi *suppress_ve); + int p2m_get_suppress_ve(struct domain *d, gfn_t gfn, bool *suppress_ve, unsigned int altp2m_idx);
By default the sve bits are not set. This patch adds a new hypercall, xc_altp2m_set_supress_ve_multi(), to set a range of sve bits. The core function, p2m_set_suppress_ve_multi(), does not break in case of a error and it is doing a best effort for setting the bits in the given range. A check for continuation is made in order to have preemption on large ranges. The gfn of the first error is stored in xen_hvm_altp2m_suppress_ve_multi.first_error and the error code is stored in xen_hvm_altp2m_suppress_ve_multi.first_error_code. If no error occurred the values will be 0. Signed-off-by: Alexandru Isaila <aisaila@bitdefender.com> --- CC: Ian Jackson <ian.jackson@eu.citrix.com> CC: Wei Liu <wl@xen.org> CC: Andrew Cooper <andrew.cooper3@citrix.com> CC: George Dunlap <George.Dunlap@eu.citrix.com> CC: Jan Beulich <jbeulich@suse.com> CC: Julien Grall <julien@xen.org> CC: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> CC: Stefano Stabellini <sstabellini@kernel.org> CC: "Roger Pau Monné" <roger.pau@citrix.com> CC: George Dunlap <george.dunlap@eu.citrix.com> CC: Razvan Cojocaru <rcojocaru@bitdefender.com> CC: Tamas K Lengyel <tamas@tklengyel.com> CC: Petre Pircalabu <ppircalabu@bitdefender.com> --- Changes since V6: - Fix commit message - Fix comments from struct xen_hvm_altp2m_suppress_ve_multi - Save the first error from altp2m_get_effective_entry() and skip set_entry() if any error occurred. - Call p2m_set_suppress_ve_multi() in p2m_set_suppress_ve(). --- tools/libxc/include/xenctrl.h | 4 ++ tools/libxc/xc_altp2m.c | 33 ++++++++++++++ xen/arch/x86/hvm/hvm.c | 20 +++++++++ xen/arch/x86/mm/p2m.c | 78 +++++++++++++++++++++++++-------- xen/include/public/hvm/hvm_op.h | 13 ++++++ xen/include/xen/mem_access.h | 3 ++ 6 files changed, 133 insertions(+), 18 deletions(-)