* [Xen-devel] [PATCH v4 0/6] remove one more shared xenheap page: shared_info
@ 2020-03-09 9:35 paul
2020-03-09 9:35 ` [Xen-devel] [PATCH v4 1/6] domain: introduce alloc/free_shared_info() helpers paul
` (5 more replies)
0 siblings, 6 replies; 10+ messages in thread
From: paul @ 2020-03-09 9:35 UTC (permalink / raw)
To: xen-devel; +Cc: Paul Durrant
From: Paul Durrant <paul@xen.org>
Paul Durrant (6):
domain: introduce alloc/free_shared_info() helpers...
x86 / p2m: remove page_list check in p2m_alloc_table...
x86 / pv: do not treat PGC_extra pages as RAM
x86 / ioreq: use a MEMF_no_refcount allocation for server pages...
mm: add 'is_special_page' inline function...
domain: use PGC_extra domheap page for shared_info
xen/arch/arm/domain.c | 10 +++----
xen/arch/arm/mm.c | 2 +-
xen/arch/x86/domain.c | 18 +++++++------
xen/arch/x86/domctl.c | 2 +-
xen/arch/x86/hvm/ioreq.c | 2 +-
xen/arch/x86/mm.c | 11 ++++----
xen/arch/x86/mm/altp2m.c | 2 +-
xen/arch/x86/mm/mem_sharing.c | 3 +--
xen/arch/x86/mm/p2m.c | 6 +++--
xen/arch/x86/mm/shadow/common.c | 13 ++++++----
xen/arch/x86/mm/shadow/multi.c | 2 +-
xen/arch/x86/numa.c | 3 +++
xen/arch/x86/pv/dom0_build.c | 6 ++++-
xen/arch/x86/pv/shim.c | 2 +-
xen/arch/x86/tboot.c | 11 +++++---
xen/common/domain.c | 46 +++++++++++++++++++++++++++++++++
xen/common/domctl.c | 2 +-
xen/common/event_channel.c | 3 +++
xen/common/time.c | 19 ++++++++++++--
xen/include/asm-x86/shared.h | 15 ++++++-----
xen/include/xen/domain.h | 3 +++
xen/include/xen/mm.h | 5 ++++
xen/include/xen/sched.h | 5 +++-
xen/include/xen/shared.h | 2 +-
24 files changed, 142 insertions(+), 51 deletions(-)
--
2.20.1
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xenproject.org
https://lists.xenproject.org/mailman/listinfo/xen-devel
^ permalink raw reply [flat|nested] 10+ messages in thread
* [Xen-devel] [PATCH v4 1/6] domain: introduce alloc/free_shared_info() helpers...
2020-03-09 9:35 [Xen-devel] [PATCH v4 0/6] remove one more shared xenheap page: shared_info paul
@ 2020-03-09 9:35 ` paul
2020-03-09 9:35 ` [Xen-devel] [PATCH v4 2/6] x86 / p2m: remove page_list check in p2m_alloc_table paul
` (4 subsequent siblings)
5 siblings, 0 replies; 10+ messages in thread
From: paul @ 2020-03-09 9:35 UTC (permalink / raw)
To: xen-devel
Cc: Stefano Stabellini, Julien Grall, Wei Liu, Paul Durrant,
Andrew Cooper, Paul Durrant, Konrad Rzeszutek Wilk, Ian Jackson,
George Dunlap, Hongyan Xia, Jan Beulich, Volodymyr Babchuk,
Roger Pau Monné
From: Paul Durrant <pdurrant@amazon.com>
... and save the MFN.
This patch modifies the 'shared_info' field of struct domain to be
a structure comprising an MFN and a virtual address. Allocations are
still done from xenheap, so the virtual address still equates to
virt_to_mfn() called on the MFN but subsequent patch will change this.
Hence the need to save the MFN.
NOTE: Whist defining the new helpers, virt_to_mfn() in common/domain.c
is made type safe.
The definition of nmi_reason() in asm-x86/shared.h is also re-
flowed to avoid overly long lines.
Signed-off-by: Paul Durrant <paul@xen.org>
Reviewed-by: Julien Grall <julien@xen.org>
Reviewed-by: Hongyan Xia <hongyxia@amazon.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
---
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Volodymyr Babchuk <Volodymyr_Babchuk@epam.com>
Cc: Andrew Cooper <andrew.cooper3@citrix.com>
Cc: George Dunlap <george.dunlap@citrix.com>
Cc: Ian Jackson <ian.jackson@eu.citrix.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Wei Liu <wl@xen.org>
Cc: "Roger Pau Monné" <roger.pau@citrix.com>
---
xen/arch/arm/domain.c | 8 ++------
xen/arch/arm/mm.c | 2 +-
xen/arch/x86/domain.c | 11 ++++-------
xen/arch/x86/mm.c | 2 +-
xen/arch/x86/pv/dom0_build.c | 2 +-
xen/arch/x86/pv/shim.c | 2 +-
xen/common/domain.c | 26 ++++++++++++++++++++++++++
xen/common/domctl.c | 2 +-
xen/common/time.c | 4 ++--
xen/include/asm-x86/shared.h | 15 ++++++++-------
xen/include/xen/domain.h | 3 +++
xen/include/xen/sched.h | 5 ++++-
xen/include/xen/shared.h | 2 +-
13 files changed, 55 insertions(+), 29 deletions(-)
diff --git a/xen/arch/arm/domain.c b/xen/arch/arm/domain.c
index 6627be2922..5298d80bd2 100644
--- a/xen/arch/arm/domain.c
+++ b/xen/arch/arm/domain.c
@@ -689,13 +689,9 @@ int arch_domain_create(struct domain *d,
if ( (rc = p2m_init(d)) != 0 )
goto fail;
- rc = -ENOMEM;
- if ( (d->shared_info = alloc_xenheap_pages(0, 0)) == NULL )
+ if ( (rc = alloc_shared_info(d, 0)) != 0 )
goto fail;
- clear_page(d->shared_info);
- share_xen_page_with_guest(virt_to_page(d->shared_info), d, SHARE_rw);
-
switch ( config->arch.gic_version )
{
case XEN_DOMCTL_CONFIG_GIC_V2:
@@ -766,7 +762,7 @@ void arch_domain_destroy(struct domain *d)
p2m_teardown(d);
domain_vgic_free(d);
domain_vuart_free(d);
- free_xenheap_page(d->shared_info);
+ free_shared_info(d);
#ifdef CONFIG_ACPI
free_xenheap_pages(d->arch.efi_acpi_table,
get_order_from_bytes(d->arch.efi_acpi_len));
diff --git a/xen/arch/arm/mm.c b/xen/arch/arm/mm.c
index 727107eefa..2bb592101d 100644
--- a/xen/arch/arm/mm.c
+++ b/xen/arch/arm/mm.c
@@ -1424,7 +1424,7 @@ int xenmem_add_to_physmap_one(
if ( idx != 0 )
return -EINVAL;
- mfn = virt_to_mfn(d->shared_info);
+ mfn = d->shared_info.mfn;
t = p2m_ram_rw;
break;
diff --git a/xen/arch/x86/domain.c b/xen/arch/x86/domain.c
index caf2ecad7e..bdcc0d972a 100644
--- a/xen/arch/x86/domain.c
+++ b/xen/arch/x86/domain.c
@@ -611,12 +611,9 @@ int arch_domain_create(struct domain *d,
* The shared_info machine address must fit in a 32-bit field within a
* 32-bit guest's start_info structure. Hence we specify MEMF_bits(32).
*/
- if ( (d->shared_info = alloc_xenheap_pages(0, MEMF_bits(32))) == NULL )
+ if ( (rc = alloc_shared_info(d, MEMF_bits(32))) != 0 )
goto fail;
- clear_page(d->shared_info);
- share_xen_page_with_guest(virt_to_page(d->shared_info), d, SHARE_rw);
-
if ( (rc = init_domain_irq_mapping(d)) != 0 )
goto fail;
@@ -664,7 +661,7 @@ int arch_domain_create(struct domain *d,
psr_domain_free(d);
iommu_domain_destroy(d);
cleanup_domain_irq_mapping(d);
- free_xenheap_page(d->shared_info);
+ free_shared_info(d);
xfree(d->arch.cpuid);
xfree(d->arch.msr);
if ( paging_initialised )
@@ -693,7 +690,7 @@ void arch_domain_destroy(struct domain *d)
pv_domain_destroy(d);
free_perdomain_mappings(d);
- free_xenheap_page(d->shared_info);
+ free_shared_info(d);
cleanup_domain_irq_mapping(d);
psr_domain_free(d);
@@ -719,7 +716,7 @@ void arch_domain_unpause(struct domain *d)
int arch_domain_soft_reset(struct domain *d)
{
- struct page_info *page = virt_to_page(d->shared_info), *new_page;
+ struct page_info *page = mfn_to_page(d->shared_info.mfn), *new_page;
int ret = 0;
struct domain *owner;
mfn_t mfn;
diff --git a/xen/arch/x86/mm.c b/xen/arch/x86/mm.c
index 62507ca651..ba7563ed3c 100644
--- a/xen/arch/x86/mm.c
+++ b/xen/arch/x86/mm.c
@@ -4540,7 +4540,7 @@ int xenmem_add_to_physmap_one(
{
case XENMAPSPACE_shared_info:
if ( idx == 0 )
- mfn = virt_to_mfn(d->shared_info);
+ mfn = d->shared_info.mfn;
break;
case XENMAPSPACE_grant_table:
rc = gnttab_map_frame(d, idx, gpfn, &mfn);
diff --git a/xen/arch/x86/pv/dom0_build.c b/xen/arch/x86/pv/dom0_build.c
index 5678da782d..dc16ef2e79 100644
--- a/xen/arch/x86/pv/dom0_build.c
+++ b/xen/arch/x86/pv/dom0_build.c
@@ -743,7 +743,7 @@ int __init dom0_construct_pv(struct domain *d,
clear_page(si);
si->nr_pages = nr_pages;
- si->shared_info = virt_to_maddr(d->shared_info);
+ si->shared_info = mfn_to_maddr(d->shared_info.mfn);
if ( !pv_shim )
si->flags = SIF_PRIVILEGED | SIF_INITDOMAIN;
diff --git a/xen/arch/x86/pv/shim.c b/xen/arch/x86/pv/shim.c
index d86e2de118..f512809dad 100644
--- a/xen/arch/x86/pv/shim.c
+++ b/xen/arch/x86/pv/shim.c
@@ -282,7 +282,7 @@ static void write_start_info(struct domain *d)
snprintf(si->magic, sizeof(si->magic), "xen-3.0-x86_%s",
is_pv_32bit_domain(d) ? "32p" : "64");
si->nr_pages = domain_tot_pages(d);
- si->shared_info = virt_to_maddr(d->shared_info);
+ si->shared_info = mfn_to_maddr(d->shared_info.mfn);
si->flags = 0;
BUG_ON(xen_hypercall_hvm_get_param(HVM_PARAM_STORE_PFN, &si->store_mfn));
BUG_ON(xen_hypercall_hvm_get_param(HVM_PARAM_STORE_EVTCHN, ¶m));
diff --git a/xen/common/domain.c b/xen/common/domain.c
index 6ad458fa6b..ba7a905258 100644
--- a/xen/common/domain.c
+++ b/xen/common/domain.c
@@ -47,6 +47,10 @@
#include <asm/guest.h>
#endif
+/* Override macros from asm/page.h to make them work with mfn_t */
+#undef virt_to_mfn
+#define virt_to_mfn(v) _mfn(__virt_to_mfn(v))
+
/* Linux config option: propageted to domain0 */
/* xen_processor_pmbits: xen control Cx, Px, ... */
unsigned int xen_processor_pmbits = XEN_PROCESSOR_PM_PX;
@@ -1644,6 +1648,28 @@ int continue_hypercall_on_cpu(
return 0;
}
+int alloc_shared_info(struct domain *d, unsigned int memflags)
+{
+ if ( (d->shared_info.virt = alloc_xenheap_pages(0, memflags)) == NULL )
+ return -ENOMEM;
+
+ d->shared_info.mfn = virt_to_mfn(d->shared_info.virt);
+
+ clear_page(d->shared_info.virt);
+ share_xen_page_with_guest(mfn_to_page(d->shared_info.mfn), d, SHARE_rw);
+
+ return 0;
+}
+
+void free_shared_info(struct domain *d)
+{
+ if ( !d->shared_info.virt )
+ return;
+
+ free_xenheap_page(d->shared_info.virt);
+ d->shared_info.virt = NULL;
+}
+
/*
* Local variables:
* mode: C
diff --git a/xen/common/domctl.c b/xen/common/domctl.c
index a69b3b59a8..81f18e63a7 100644
--- a/xen/common/domctl.c
+++ b/xen/common/domctl.c
@@ -196,7 +196,7 @@ void getdomaininfo(struct domain *d, struct xen_domctl_getdomaininfo *info)
info->outstanding_pages = d->outstanding_pages;
info->shr_pages = atomic_read(&d->shr_pages);
info->paged_pages = atomic_read(&d->paged_pages);
- info->shared_info_frame = mfn_to_gmfn(d, virt_to_mfn(d->shared_info));
+ info->shared_info_frame = mfn_to_gmfn(d, mfn_x(d->shared_info.mfn));
BUG_ON(SHARED_M2P(info->shared_info_frame));
info->cpupool = cpupool_get_id(d);
diff --git a/xen/common/time.c b/xen/common/time.c
index 82336e2d5a..58fa9abc40 100644
--- a/xen/common/time.c
+++ b/xen/common/time.c
@@ -110,9 +110,9 @@ void update_domain_wallclock_time(struct domain *d)
shared_info(d, wc_nsec) = wc_nsec;
#ifdef CONFIG_X86
if ( likely(!has_32bit_shinfo(d)) )
- d->shared_info->native.wc_sec_hi = sec >> 32;
+ d->shared_info.virt->native.wc_sec_hi = sec >> 32;
else
- d->shared_info->compat.arch.wc_sec_hi = sec >> 32;
+ d->shared_info.virt->compat.arch.wc_sec_hi = sec >> 32;
#else
shared_info(d, wc_sec_hi) = sec >> 32;
#endif
diff --git a/xen/include/asm-x86/shared.h b/xen/include/asm-x86/shared.h
index af5d959d04..d4588e08a6 100644
--- a/xen/include/asm-x86/shared.h
+++ b/xen/include/asm-x86/shared.h
@@ -1,24 +1,25 @@
#ifndef __XEN_X86_SHARED_H__
#define __XEN_X86_SHARED_H__
-#define nmi_reason(d) (!has_32bit_shinfo(d) ? \
- (u32 *)&(d)->shared_info->native.arch.nmi_reason : \
- (u32 *)&(d)->shared_info->compat.arch.nmi_reason)
+#define nmi_reason(d) \
+ (!has_32bit_shinfo(d) ? \
+ (u32 *)&(d)->shared_info.virt->native.arch.nmi_reason : \
+ (u32 *)&(d)->shared_info.virt->compat.arch.nmi_reason)
#define GET_SET_SHARED(type, field) \
static inline type arch_get_##field(const struct domain *d) \
{ \
return !has_32bit_shinfo(d) ? \
- d->shared_info->native.arch.field : \
- d->shared_info->compat.arch.field; \
+ d->shared_info.virt->native.arch.field : \
+ d->shared_info.virt->compat.arch.field; \
} \
static inline void arch_set_##field(struct domain *d, \
type val) \
{ \
if ( !has_32bit_shinfo(d) ) \
- d->shared_info->native.arch.field = val; \
+ d->shared_info.virt->native.arch.field = val; \
else \
- d->shared_info->compat.arch.field = val; \
+ d->shared_info.virt->compat.arch.field = val; \
}
#define GET_SET_VCPU(type, field) \
diff --git a/xen/include/xen/domain.h b/xen/include/xen/domain.h
index 7e51d361de..740e2032ad 100644
--- a/xen/include/xen/domain.h
+++ b/xen/include/xen/domain.h
@@ -130,4 +130,7 @@ struct vnuma_info {
void vnuma_destroy(struct vnuma_info *vnuma);
+int alloc_shared_info(struct domain *d, unsigned int memflags);
+void free_shared_info(struct domain *d);
+
#endif /* __XEN_DOMAIN_H__ */
diff --git a/xen/include/xen/sched.h b/xen/include/xen/sched.h
index 3a4f43098c..f41d0ad2a0 100644
--- a/xen/include/xen/sched.h
+++ b/xen/include/xen/sched.h
@@ -346,7 +346,10 @@ struct domain
unsigned int max_vcpus;
struct vcpu **vcpu;
- shared_info_t *shared_info; /* shared data area */
+ struct {
+ mfn_t mfn;
+ shared_info_t *virt;
+ } shared_info; /* shared data area */
spinlock_t domain_lock;
diff --git a/xen/include/xen/shared.h b/xen/include/xen/shared.h
index a411a8a3e3..57b2ff1e34 100644
--- a/xen/include/xen/shared.h
+++ b/xen/include/xen/shared.h
@@ -43,7 +43,7 @@ typedef struct vcpu_info vcpu_info_t;
extern vcpu_info_t dummy_vcpu_info;
-#define shared_info(d, field) __shared_info(d, (d)->shared_info, field)
+#define shared_info(d, field) __shared_info(d, (d)->shared_info.virt, field)
#define vcpu_info(v, field) __vcpu_info(v, (v)->vcpu_info, field)
#endif /* __XEN_SHARED_H__ */
--
2.20.1
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xenproject.org
https://lists.xenproject.org/mailman/listinfo/xen-devel
^ permalink raw reply related [flat|nested] 10+ messages in thread
* [Xen-devel] [PATCH v4 2/6] x86 / p2m: remove page_list check in p2m_alloc_table...
2020-03-09 9:35 [Xen-devel] [PATCH v4 0/6] remove one more shared xenheap page: shared_info paul
2020-03-09 9:35 ` [Xen-devel] [PATCH v4 1/6] domain: introduce alloc/free_shared_info() helpers paul
@ 2020-03-09 9:35 ` paul
2020-03-09 9:59 ` Jan Beulich
2020-03-09 9:35 ` [Xen-devel] [PATCH v4 3/6] x86 / pv: do not treat PGC_extra pages as RAM paul
` (3 subsequent siblings)
5 siblings, 1 reply; 10+ messages in thread
From: paul @ 2020-03-09 9:35 UTC (permalink / raw)
To: xen-devel
Cc: Wei Liu, Paul Durrant, Andrew Cooper, Paul Durrant,
George Dunlap, Jan Beulich, Roger Pau Monné
From: Paul Durrant <pdurrant@amazon.com>
... and replace with a check of domain_tot_pages().
The check of page_list prevents the prior allocation of PGC_extra pages,
whereas what the code is trying to verify is that the toolstack has not
already RAM for the domain.
Signed-off-by: Paul Durrant <paul@xen.org>
---
Cc: Jan Beulich <jbeulich@suse.com>
Cc: Andrew Cooper <andrew.cooper3@citrix.com>
Cc: George Dunlap <george.dunlap@citrix.com>
Cc: Wei Liu <wl@xen.org>
Cc: "Roger Pau Monné" <roger.pau@citrix.com>
v4:
- Re-worked so as not to completely remove the check
v2:
- New in v2
---
xen/arch/x86/mm/p2m.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/xen/arch/x86/mm/p2m.c b/xen/arch/x86/mm/p2m.c
index 3719deae77..9f51370327 100644
--- a/xen/arch/x86/mm/p2m.c
+++ b/xen/arch/x86/mm/p2m.c
@@ -695,8 +695,7 @@ int p2m_alloc_table(struct p2m_domain *p2m)
p2m_lock(p2m);
- if ( p2m_is_hostp2m(p2m)
- && !page_list_empty(&d->page_list) )
+ if ( p2m_is_hostp2m(p2m) && domain_tot_pages(d) )
{
P2M_ERROR("dom %d already has memory allocated\n", d->domain_id);
p2m_unlock(p2m);
--
2.20.1
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xenproject.org
https://lists.xenproject.org/mailman/listinfo/xen-devel
^ permalink raw reply related [flat|nested] 10+ messages in thread
* [Xen-devel] [PATCH v4 3/6] x86 / pv: do not treat PGC_extra pages as RAM
2020-03-09 9:35 [Xen-devel] [PATCH v4 0/6] remove one more shared xenheap page: shared_info paul
2020-03-09 9:35 ` [Xen-devel] [PATCH v4 1/6] domain: introduce alloc/free_shared_info() helpers paul
2020-03-09 9:35 ` [Xen-devel] [PATCH v4 2/6] x86 / p2m: remove page_list check in p2m_alloc_table paul
@ 2020-03-09 9:35 ` paul
2020-03-09 9:35 ` [Xen-devel] [PATCH v4 4/6] x86 / ioreq: use a MEMF_no_refcount allocation for server pages paul
` (2 subsequent siblings)
5 siblings, 0 replies; 10+ messages in thread
From: paul @ 2020-03-09 9:35 UTC (permalink / raw)
To: xen-devel
Cc: Wei Liu, Paul Durrant, Andrew Cooper, Paul Durrant, Jan Beulich,
Roger Pau Monné
From: Paul Durrant <pdurrant@amazon.com>
This patch modifies several places walking the domain's page_list to make
them ignore PGC_extra pages:
- dump_pageframe_info() should ignore PGC_extra pages in its dump as it
determines whether to dump using domain_tot_pages() which also ignores
PGC_extra pages.
- arch_set_info_guest() is looking for an L4 page table which will
definitely not be in a PGC_extra page.
- audit_p2m() should ignore PGC_extra pages as it is perfectly legitimate
for them not to be present in the P2M.
- dump_nama() should ignore PGC_extra pages as they are essentially
uninteresting in that context.
- dom0_construct_pv() should ignore PGC_extra pages when setting up the
physmap as they are only created for special purposes and, if they need
to be mapped, will be mapped explicitly for whatever purpose is relevant.
- tboot_gen_domain_integrity() should ignore PGC_extra pages as they should
not form part of the measurement.
Signed-off-by: Paul Durrant <paul@xen.org>
---
Cc: Jan Beulich <jbeulich@suse.com>
Cc: Andrew Cooper <andrew.cooper3@citrix.com>
Cc: Wei Liu <wl@xen.org>
Cc: "Roger Pau Monné" <roger.pau@citrix.com>
v4:
- Expand to cover more than just dom0_construct_pv()
v2:
- New in v2
---
xen/arch/x86/domain.c | 6 +++++-
xen/arch/x86/mm/p2m.c | 3 +++
xen/arch/x86/numa.c | 3 +++
xen/arch/x86/pv/dom0_build.c | 4 ++++
xen/arch/x86/tboot.c | 7 ++++++-
5 files changed, 21 insertions(+), 2 deletions(-)
diff --git a/xen/arch/x86/domain.c b/xen/arch/x86/domain.c
index bdcc0d972a..f6ed25e8ee 100644
--- a/xen/arch/x86/domain.c
+++ b/xen/arch/x86/domain.c
@@ -231,6 +231,9 @@ void dump_pageframe_info(struct domain *d)
unsigned int index = MASK_EXTR(page->u.inuse.type_info,
PGT_type_mask);
+ if ( page->count_info & PGC_extra )
+ continue;
+
if ( ++total[index] > 16 )
{
switch ( page->u.inuse.type_info & PGT_type_mask )
@@ -1044,7 +1047,8 @@ int arch_set_info_guest(
{
struct page_info *page = page_list_remove_head(&d->page_list);
- if ( page_lock(page) )
+ if ( !(page->count_info & PGC_extra) &&
+ page_lock(page) )
{
if ( (page->u.inuse.type_info & PGT_type_mask) ==
PGT_l4_page_table )
diff --git a/xen/arch/x86/mm/p2m.c b/xen/arch/x86/mm/p2m.c
index 9f51370327..71d2fb9bbc 100644
--- a/xen/arch/x86/mm/p2m.c
+++ b/xen/arch/x86/mm/p2m.c
@@ -2843,6 +2843,9 @@ void audit_p2m(struct domain *d,
spin_lock(&d->page_alloc_lock);
page_list_for_each ( page, &d->page_list )
{
+ if ( page->count_info & PGC_extra )
+ continue;
+
mfn = mfn_x(page_to_mfn(page));
P2M_PRINTK("auditing guest page, mfn=%#lx\n", mfn);
diff --git a/xen/arch/x86/numa.c b/xen/arch/x86/numa.c
index f1066c59c7..7e5aa8dc95 100644
--- a/xen/arch/x86/numa.c
+++ b/xen/arch/x86/numa.c
@@ -428,6 +428,9 @@ static void dump_numa(unsigned char key)
spin_lock(&d->page_alloc_lock);
page_list_for_each(page, &d->page_list)
{
+ if ( page->count_info & PGC_extra )
+ break;
+
i = phys_to_nid(page_to_maddr(page));
page_num_node[i]++;
}
diff --git a/xen/arch/x86/pv/dom0_build.c b/xen/arch/x86/pv/dom0_build.c
index dc16ef2e79..f8f1bbe2f4 100644
--- a/xen/arch/x86/pv/dom0_build.c
+++ b/xen/arch/x86/pv/dom0_build.c
@@ -792,6 +792,10 @@ int __init dom0_construct_pv(struct domain *d,
{
mfn = mfn_x(page_to_mfn(page));
BUG_ON(SHARED_M2P(get_gpfn_from_mfn(mfn)));
+
+ if ( page->count_info & PGC_extra )
+ continue;
+
if ( get_gpfn_from_mfn(mfn) >= count )
{
BUG_ON(is_pv_32bit_domain(d));
diff --git a/xen/arch/x86/tboot.c b/xen/arch/x86/tboot.c
index 8c232270b4..6cc020cb71 100644
--- a/xen/arch/x86/tboot.c
+++ b/xen/arch/x86/tboot.c
@@ -220,7 +220,12 @@ static void tboot_gen_domain_integrity(const uint8_t key[TB_KEY_SIZE],
spin_lock(&d->page_alloc_lock);
page_list_for_each(page, &d->page_list)
{
- void *pg = __map_domain_page(page);
+ void *pg;
+
+ if ( page->count_info & PGC_extra )
+ continue;
+
+ pg = __map_domain_page(page);
vmac_update(pg, PAGE_SIZE, &ctx);
unmap_domain_page(pg);
}
--
2.20.1
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xenproject.org
https://lists.xenproject.org/mailman/listinfo/xen-devel
^ permalink raw reply related [flat|nested] 10+ messages in thread
* [Xen-devel] [PATCH v4 4/6] x86 / ioreq: use a MEMF_no_refcount allocation for server pages...
2020-03-09 9:35 [Xen-devel] [PATCH v4 0/6] remove one more shared xenheap page: shared_info paul
` (2 preceding siblings ...)
2020-03-09 9:35 ` [Xen-devel] [PATCH v4 3/6] x86 / pv: do not treat PGC_extra pages as RAM paul
@ 2020-03-09 9:35 ` paul
2020-03-09 9:35 ` [Xen-devel] [PATCH v4 5/6] mm: add 'is_special_page' inline function paul
2020-03-09 9:35 ` [Xen-devel] [PATCH v4 6/6] domain: use PGC_extra domheap page for shared_info paul
5 siblings, 0 replies; 10+ messages in thread
From: paul @ 2020-03-09 9:35 UTC (permalink / raw)
To: xen-devel
Cc: Wei Liu, Paul Durrant, Andrew Cooper, Paul Durrant, Jan Beulich,
Roger Pau Monné
From: Paul Durrant <pdurrant@amazon.com>
... now that it is safe to assign them.
This avoids relying on libxl (or whatever toolstack is in use) setting
max_pages up with sufficient 'slop' to allow all necessary ioreq server
pages to be allocated.
Signed-off-by: Paul Durrant <paul@xen.org>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
---
Cc: Andrew Cooper <andrew.cooper3@citrix.com>
Cc: Wei Liu <wl@xen.org>
Cc: "Roger Pau Monné" <roger.pau@citrix.com>
v2:
- New in v2
---
xen/arch/x86/hvm/ioreq.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/xen/arch/x86/hvm/ioreq.c b/xen/arch/x86/hvm/ioreq.c
index f8a5c81546..648ef9137f 100644
--- a/xen/arch/x86/hvm/ioreq.c
+++ b/xen/arch/x86/hvm/ioreq.c
@@ -375,7 +375,7 @@ static int hvm_alloc_ioreq_mfn(struct hvm_ioreq_server *s, bool buf)
return 0;
}
- page = alloc_domheap_page(s->target, 0);
+ page = alloc_domheap_page(s->target, MEMF_no_refcount);
if ( !page )
return -ENOMEM;
--
2.20.1
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xenproject.org
https://lists.xenproject.org/mailman/listinfo/xen-devel
^ permalink raw reply related [flat|nested] 10+ messages in thread
* [Xen-devel] [PATCH v4 5/6] mm: add 'is_special_page' inline function...
2020-03-09 9:35 [Xen-devel] [PATCH v4 0/6] remove one more shared xenheap page: shared_info paul
` (3 preceding siblings ...)
2020-03-09 9:35 ` [Xen-devel] [PATCH v4 4/6] x86 / ioreq: use a MEMF_no_refcount allocation for server pages paul
@ 2020-03-09 9:35 ` paul
2020-03-09 9:35 ` [Xen-devel] [PATCH v4 6/6] domain: use PGC_extra domheap page for shared_info paul
5 siblings, 0 replies; 10+ messages in thread
From: paul @ 2020-03-09 9:35 UTC (permalink / raw)
To: xen-devel
Cc: Tamas K Lengyel, Julien Grall, Wei Liu, Paul Durrant,
Andrew Cooper, Paul Durrant, Konrad Rzeszutek Wilk, Ian Jackson,
George Dunlap, Tim Deegan, Stefano Stabellini, Jan Beulich,
Roger Pau Monné
From: Paul Durrant <pdurrant@amazon.com>
... to cover xenheap and PGC_extra pages.
PGC_extra pages are intended to hold data structures that are associated
with a domain and may be mapped by that domain. They should not be treated
as 'normal' guest pages (i.e. RAM or page tables). Hence, in many cases
where code currently tests is_xen_heap_page() it should also check for
the PGC_extra bit in 'count_info'.
This patch therefore defines is_special_page() to cover both cases and
converts tests if is_xen_heap_page() to is_special_page() where
appropriate.
Signed-off-by: Paul Durrant <paul@xen.org>
Acked-by: Tamas K Lengyel <tamas@tklengyel.com>
---
Cc: Jan Beulich <jbeulich@suse.com>
Cc: Andrew Cooper <andrew.cooper3@citrix.com>
Cc: Wei Liu <wl@xen.org>
Cc: "Roger Pau Monné" <roger.pau@citrix.com>
Cc: George Dunlap <george.dunlap@citrix.com>
Cc: Ian Jackson <ian.jackson@eu.citrix.com>
Cc: Julien Grall <julien@xen.org>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Tim Deegan <tim@xen.org>
v4:
- Use inline function instead of macro
- Add missing conversions from is_xen_heap_page()
v3:
- Delete obsolete comment.
v2:
- New in v2
---
xen/arch/x86/domctl.c | 2 +-
xen/arch/x86/mm.c | 9 ++++-----
xen/arch/x86/mm/altp2m.c | 2 +-
xen/arch/x86/mm/mem_sharing.c | 3 +--
xen/arch/x86/mm/shadow/common.c | 13 ++++++++-----
xen/arch/x86/mm/shadow/multi.c | 2 +-
xen/arch/x86/tboot.c | 4 ++--
xen/include/xen/mm.h | 5 +++++
8 files changed, 23 insertions(+), 17 deletions(-)
diff --git a/xen/arch/x86/domctl.c b/xen/arch/x86/domctl.c
index ed86762fa6..add70126b9 100644
--- a/xen/arch/x86/domctl.c
+++ b/xen/arch/x86/domctl.c
@@ -394,7 +394,7 @@ long arch_do_domctl(
page = get_page_from_gfn(d, gfn, &t, P2M_ALLOC);
if ( unlikely(!page) ||
- unlikely(is_xen_heap_page(page)) )
+ unlikely(is_special_page(page)) )
{
if ( unlikely(p2m_is_broken(t)) )
type = XEN_DOMCTL_PFINFO_BROKEN;
diff --git a/xen/arch/x86/mm.c b/xen/arch/x86/mm.c
index ba7563ed3c..353bde5c2c 100644
--- a/xen/arch/x86/mm.c
+++ b/xen/arch/x86/mm.c
@@ -1014,7 +1014,7 @@ get_page_from_l1e(
unsigned long cacheattr = pte_flags_to_cacheattr(l1f);
int err;
- if ( is_xen_heap_page(page) )
+ if ( is_special_page(page) )
{
if ( write )
put_page_type(page);
@@ -2447,7 +2447,7 @@ static int cleanup_page_mappings(struct page_info *page)
{
page->count_info &= ~PGC_cacheattr_mask;
- BUG_ON(is_xen_heap_page(page));
+ BUG_ON(is_special_page(page));
rc = update_xen_mappings(mfn, 0);
}
@@ -2477,7 +2477,7 @@ static int cleanup_page_mappings(struct page_info *page)
rc = rc2;
}
- if ( likely(!is_xen_heap_page(page)) )
+ if ( likely(!is_special_page(page)) )
{
ASSERT((page->u.inuse.type_info &
(PGT_type_mask | PGT_count_mask)) == PGT_writable_page);
@@ -4216,8 +4216,7 @@ int steal_page(
if ( !(owner = page_get_owner_and_reference(page)) )
goto fail;
- if ( owner != d || is_xen_heap_page(page) ||
- (page->count_info & PGC_extra) )
+ if ( owner != d || is_special_page(page) )
goto fail_put;
/*
diff --git a/xen/arch/x86/mm/altp2m.c b/xen/arch/x86/mm/altp2m.c
index 50768f2547..c091b03ea3 100644
--- a/xen/arch/x86/mm/altp2m.c
+++ b/xen/arch/x86/mm/altp2m.c
@@ -77,7 +77,7 @@ int altp2m_vcpu_enable_ve(struct vcpu *v, gfn_t gfn)
* pageable() predicate for this, due to it having the same properties
* that we want.
*/
- if ( !p2m_is_pageable(p2mt) || is_xen_heap_page(pg) )
+ if ( !p2m_is_pageable(p2mt) || is_special_page(pg) )
{
rc = -EINVAL;
goto err;
diff --git a/xen/arch/x86/mm/mem_sharing.c b/xen/arch/x86/mm/mem_sharing.c
index 3835bc928f..f49f27a3ef 100644
--- a/xen/arch/x86/mm/mem_sharing.c
+++ b/xen/arch/x86/mm/mem_sharing.c
@@ -840,9 +840,8 @@ static int nominate_page(struct domain *d, gfn_t gfn,
if ( !p2m_is_sharable(p2mt) )
goto out;
- /* Skip xen heap pages */
page = mfn_to_page(mfn);
- if ( !page || is_xen_heap_page(page) )
+ if ( !page || is_special_page(page) )
goto out;
/* Check if there are mem_access/remapped altp2m entries for this page */
diff --git a/xen/arch/x86/mm/shadow/common.c b/xen/arch/x86/mm/shadow/common.c
index cba3ab1eba..e835940d86 100644
--- a/xen/arch/x86/mm/shadow/common.c
+++ b/xen/arch/x86/mm/shadow/common.c
@@ -2087,19 +2087,22 @@ static int sh_remove_all_mappings(struct domain *d, mfn_t gmfn, gfn_t gfn)
* The qemu helper process has an untyped mapping of this dom's RAM
* and the HVM restore program takes another.
* Also allow one typed refcount for
- * - Xen heap pages, to match share_xen_page_with_guest(),
- * - ioreq server pages, to match prepare_ring_for_helper().
+ * - special pages, which are explicitly referenced and mapped by
+ * Xen.
+ * - ioreq server pages, which may be special pages or normal
+ * guest pages with an extra reference taken by
+ * prepare_ring_for_helper().
*/
if ( !(shadow_mode_external(d)
&& (page->count_info & PGC_count_mask) <= 3
&& ((page->u.inuse.type_info & PGT_count_mask)
- == (is_xen_heap_page(page) ||
+ == (is_special_page(page) ||
(is_hvm_domain(d) && is_ioreq_server_page(d, page))))) )
printk(XENLOG_G_ERR "can't find all mappings of mfn %"PRI_mfn
- " (gfn %"PRI_gfn"): c=%lx t=%lx x=%d i=%d\n",
+ " (gfn %"PRI_gfn"): c=%lx t=%lx s=%d i=%d\n",
mfn_x(gmfn), gfn_x(gfn),
page->count_info, page->u.inuse.type_info,
- !!is_xen_heap_page(page),
+ !!is_special_page(page),
(is_hvm_domain(d) && is_ioreq_server_page(d, page)));
}
diff --git a/xen/arch/x86/mm/shadow/multi.c b/xen/arch/x86/mm/shadow/multi.c
index 26798b317c..ac19d203d7 100644
--- a/xen/arch/x86/mm/shadow/multi.c
+++ b/xen/arch/x86/mm/shadow/multi.c
@@ -559,7 +559,7 @@ _sh_propagate(struct vcpu *v,
* caching attributes in the shadows to match what was asked for.
*/
if ( (level == 1) && is_hvm_domain(d) &&
- !is_xen_heap_mfn(target_mfn) )
+ !is_special_page(mfn_to_page(target_mfn)) )
{
int type;
diff --git a/xen/arch/x86/tboot.c b/xen/arch/x86/tboot.c
index 6cc020cb71..2fd7ce5305 100644
--- a/xen/arch/x86/tboot.c
+++ b/xen/arch/x86/tboot.c
@@ -189,7 +189,7 @@ static void update_pagetable_mac(vmac_ctx_t *ctx)
if ( !mfn_valid(_mfn(mfn)) )
continue;
- if ( is_page_in_use(page) && !is_xen_heap_page(page) )
+ if ( is_page_in_use(page) && !is_special_page(page) )
{
if ( page->count_info & PGC_page_table )
{
@@ -294,7 +294,7 @@ static void tboot_gen_xenheap_integrity(const uint8_t key[TB_KEY_SIZE],
+ 3 * PAGE_SIZE)) )
continue; /* skip tboot and its page tables */
- if ( is_page_in_use(page) && is_xen_heap_page(page) )
+ if ( is_page_in_use(page) && is_special_page(page) )
{
void *pg;
diff --git a/xen/include/xen/mm.h b/xen/include/xen/mm.h
index d0d095d9c7..373de59969 100644
--- a/xen/include/xen/mm.h
+++ b/xen/include/xen/mm.h
@@ -285,6 +285,11 @@ extern struct domain *dom_cow;
#include <asm/mm.h>
+static inline bool is_special_page(struct page_info *page)
+{
+ return is_xen_heap_page(page) || (page->count_info & PGC_extra);
+}
+
#ifndef page_list_entry
struct page_list_head
{
--
2.20.1
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xenproject.org
https://lists.xenproject.org/mailman/listinfo/xen-devel
^ permalink raw reply related [flat|nested] 10+ messages in thread
* [Xen-devel] [PATCH v4 6/6] domain: use PGC_extra domheap page for shared_info
2020-03-09 9:35 [Xen-devel] [PATCH v4 0/6] remove one more shared xenheap page: shared_info paul
` (4 preceding siblings ...)
2020-03-09 9:35 ` [Xen-devel] [PATCH v4 5/6] mm: add 'is_special_page' inline function paul
@ 2020-03-09 9:35 ` paul
2020-03-09 10:00 ` Durrant, Paul
5 siblings, 1 reply; 10+ messages in thread
From: paul @ 2020-03-09 9:35 UTC (permalink / raw)
To: xen-devel
Cc: Stefano Stabellini, Julien Grall, Wei Liu, Paul Durrant,
Andrew Cooper, Paul Durrant, Konrad Rzeszutek Wilk, Ian Jackson,
George Dunlap, Jan Beulich, Volodymyr Babchuk
From: Paul Durrant <pdurrant@amazon.com>
Currently shared_info is a shared xenheap page but shared xenheap pages
complicate future plans for live-update of Xen so it is desirable to,
where possible, not use them [1]. This patch therefore converts shared_info
into a PGC_extra domheap page. This does entail freeing shared_info during
domain_relinquish_resources() rather than domain_destroy() so care is
needed to avoid de-referencing a NULL shared_info pointer hence some
extra checks of 'is_dying' are needed.
NOTE: For Arm, the call to free_shared_info() in arch_domain_destroy() is
left in place since it is idempotent and called in the error path for
arch_domain_create().
[1] See https://lists.xenproject.org/archives/html/xen-devel/2020-02/msg02018.html
Signed-off-by: Paul Durrant <paul@xen.org>
---
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Julien Grall <julien@xen.org>
Cc: Volodymyr Babchuk <Volodymyr_Babchuk@epam.com>
Cc: Andrew Cooper <andrew.cooper3@citrix.com>
Cc: George Dunlap <george.dunlap@citrix.com>
Cc: Ian Jackson <ian.jackson@eu.citrix.com>
Cc: Jan Beulich <jbeulich@suse.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Wei Liu <wl@xen.org>
v2:
- Addressed comments from Julien
- Expanded the commit comment to explain why this patch is wanted
---
xen/arch/arm/domain.c | 2 ++
xen/arch/x86/domain.c | 3 ++-
xen/common/domain.c | 28 ++++++++++++++++++++++++----
xen/common/event_channel.c | 3 +++
xen/common/time.c | 15 +++++++++++++++
5 files changed, 46 insertions(+), 5 deletions(-)
diff --git a/xen/arch/arm/domain.c b/xen/arch/arm/domain.c
index 5298d80bd2..741f6dd444 100644
--- a/xen/arch/arm/domain.c
+++ b/xen/arch/arm/domain.c
@@ -1005,6 +1005,8 @@ int domain_relinquish_resources(struct domain *d)
BUG();
}
+ free_shared_info(d);
+
return 0;
}
diff --git a/xen/arch/x86/domain.c b/xen/arch/x86/domain.c
index f6ed25e8ee..d962835f33 100644
--- a/xen/arch/x86/domain.c
+++ b/xen/arch/x86/domain.c
@@ -693,7 +693,6 @@ void arch_domain_destroy(struct domain *d)
pv_domain_destroy(d);
free_perdomain_mappings(d);
- free_shared_info(d);
cleanup_domain_irq_mapping(d);
psr_domain_free(d);
@@ -2249,6 +2248,8 @@ int domain_relinquish_resources(struct domain *d)
if ( is_hvm_domain(d) )
hvm_domain_relinquish_resources(d);
+ free_shared_info(d);
+
return 0;
}
diff --git a/xen/common/domain.c b/xen/common/domain.c
index ba7a905258..886206f648 100644
--- a/xen/common/domain.c
+++ b/xen/common/domain.c
@@ -1650,24 +1650,44 @@ int continue_hypercall_on_cpu(
int alloc_shared_info(struct domain *d, unsigned int memflags)
{
- if ( (d->shared_info.virt = alloc_xenheap_pages(0, memflags)) == NULL )
+ struct page_info *pg;
+
+ pg = alloc_domheap_page(d, MEMF_no_refcount | memflags);
+ if ( !pg )
return -ENOMEM;
- d->shared_info.mfn = virt_to_mfn(d->shared_info.virt);
+ if ( !get_page_and_type(pg, d, PGT_writable_page) )
+ {
+ /*
+ * The domain should not be running at this point so there is
+ * no way we should reach this error path.
+ */
+ ASSERT_UNREACHABLE();
+ return -ENODATA;
+ }
+
+ d->shared_info.mfn = page_to_mfn(pg);
+ d->shared_info.virt = __map_domain_page_global(pg);
clear_page(d->shared_info.virt);
- share_xen_page_with_guest(mfn_to_page(d->shared_info.mfn), d, SHARE_rw);
return 0;
}
void free_shared_info(struct domain *d)
{
+ struct page_info *pg;
+
if ( !d->shared_info.virt )
return;
- free_xenheap_page(d->shared_info.virt);
+ unmap_domain_page_global(d->shared_info.virt);
d->shared_info.virt = NULL;
+
+ pg = mfn_to_page(d->shared_info.mfn);
+
+ put_page_alloc_ref(pg);
+ put_page_and_type(pg);
}
/*
diff --git a/xen/common/event_channel.c b/xen/common/event_channel.c
index e86e2bfab0..a17422284d 100644
--- a/xen/common/event_channel.c
+++ b/xen/common/event_channel.c
@@ -1325,6 +1325,9 @@ void evtchn_destroy(struct domain *d)
{
unsigned int i;
+ /* This must be done before shared_info is freed */
+ BUG_ON(!d->shared_info.virt);
+
/* After this barrier no new event-channel allocations can occur. */
BUG_ON(!d->is_dying);
spin_barrier(&d->event_lock);
diff --git a/xen/common/time.c b/xen/common/time.c
index 58fa9abc40..ada02faf07 100644
--- a/xen/common/time.c
+++ b/xen/common/time.c
@@ -99,6 +99,18 @@ void update_domain_wallclock_time(struct domain *d)
uint32_t *wc_version;
uint64_t sec;
+ if ( d != current->domain )
+ {
+ /*
+ * We need to check is_dying here as, if it is set, the
+ * shared_info may have been freed. To do this safely we need
+ * hold the domain lock.
+ */
+ domain_lock(d);
+ if ( d->is_dying )
+ goto unlock;
+ }
+
spin_lock(&wc_lock);
wc_version = &shared_info(d, wc_version);
@@ -121,6 +133,9 @@ void update_domain_wallclock_time(struct domain *d)
*wc_version = version_update_end(*wc_version);
spin_unlock(&wc_lock);
+ unlock:
+ if ( d != current->domain )
+ domain_unlock(d);
}
/* Set clock to <secs,usecs> after 00:00:00 UTC, 1 January, 1970. */
--
2.20.1
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xenproject.org
https://lists.xenproject.org/mailman/listinfo/xen-devel
^ permalink raw reply related [flat|nested] 10+ messages in thread
* Re: [Xen-devel] [PATCH v4 2/6] x86 / p2m: remove page_list check in p2m_alloc_table...
2020-03-09 9:35 ` [Xen-devel] [PATCH v4 2/6] x86 / p2m: remove page_list check in p2m_alloc_table paul
@ 2020-03-09 9:59 ` Jan Beulich
2020-03-09 10:07 ` Paul Durrant
0 siblings, 1 reply; 10+ messages in thread
From: Jan Beulich @ 2020-03-09 9:59 UTC (permalink / raw)
To: paul
Cc: Wei Liu, Andrew Cooper, Paul Durrant, George Dunlap, xen-devel,
Roger Pau Monné
On 09.03.2020 10:35, paul@xen.org wrote:
> From: Paul Durrant <pdurrant@amazon.com>
>
> ... and replace with a check of domain_tot_pages().
>
> The check of page_list prevents the prior allocation of PGC_extra pages,
> whereas what the code is trying to verify is that the toolstack has not
> already RAM for the domain.
>
> Signed-off-by: Paul Durrant <paul@xen.org>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
preferably with "remove" in the subject replaced by the "replace"
currently at the beginning of the description. (It also looks as
if there was "allocated" or some such missing near the end of the
description.)
Jan
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xenproject.org
https://lists.xenproject.org/mailman/listinfo/xen-devel
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [Xen-devel] [PATCH v4 6/6] domain: use PGC_extra domheap page for shared_info
2020-03-09 9:35 ` [Xen-devel] [PATCH v4 6/6] domain: use PGC_extra domheap page for shared_info paul
@ 2020-03-09 10:00 ` Durrant, Paul
0 siblings, 0 replies; 10+ messages in thread
From: Durrant, Paul @ 2020-03-09 10:00 UTC (permalink / raw)
To: paul, xen-devel
Cc: Stefano Stabellini, Julien Grall, Wei Liu, Konrad Rzeszutek Wilk,
Andrew Cooper, Ian Jackson, George Dunlap, Jan Beulich,
Volodymyr Babchuk
> -----Original Message-----
> From: paul@xen.org <paul@xen.org>
> Sent: 09 March 2020 09:35
> To: xen-devel@lists.xenproject.org
> Cc: Durrant, Paul <pdurrant@amazon.co.uk>; Paul Durrant <paul@xen.org>; Stefano Stabellini
> <sstabellini@kernel.org>; Julien Grall <julien@xen.org>; Volodymyr Babchuk
> <Volodymyr_Babchuk@epam.com>; Andrew Cooper <andrew.cooper3@citrix.com>; George Dunlap
> <george.dunlap@citrix.com>; Ian Jackson <ian.jackson@eu.citrix.com>; Jan Beulich <jbeulich@suse.com>;
> Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>; Wei Liu <wl@xen.org>
> Subject: [PATCH v4 6/6] domain: use PGC_extra domheap page for shared_info
>
> From: Paul Durrant <pdurrant@amazon.com>
>
> Currently shared_info is a shared xenheap page but shared xenheap pages
> complicate future plans for live-update of Xen so it is desirable to,
> where possible, not use them [1]. This patch therefore converts shared_info
> into a PGC_extra domheap page. This does entail freeing shared_info during
> domain_relinquish_resources() rather than domain_destroy() so care is
> needed to avoid de-referencing a NULL shared_info pointer hence some
> extra checks of 'is_dying' are needed.
>
> NOTE: For Arm, the call to free_shared_info() in arch_domain_destroy() is
> left in place since it is idempotent and called in the error path for
> arch_domain_create().
>
> [1] See https://lists.xenproject.org/archives/html/xen-devel/2020-02/msg02018.html
>
> Signed-off-by: Paul Durrant <paul@xen.org>
I realise I forgot to fold in the new dump function for shared_info (needed since it will no longer feature in the dump of xen pages) so I will send a v5 of this series shortly.
Paul
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xenproject.org
https://lists.xenproject.org/mailman/listinfo/xen-devel
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [Xen-devel] [PATCH v4 2/6] x86 / p2m: remove page_list check in p2m_alloc_table...
2020-03-09 9:59 ` Jan Beulich
@ 2020-03-09 10:07 ` Paul Durrant
0 siblings, 0 replies; 10+ messages in thread
From: Paul Durrant @ 2020-03-09 10:07 UTC (permalink / raw)
To: 'Jan Beulich'
Cc: 'Wei Liu', 'Andrew Cooper',
'Paul Durrant', 'George Dunlap',
xen-devel, 'Roger Pau Monné'
> -----Original Message-----
> From: Jan Beulich <jbeulich@suse.com>
> Sent: 09 March 2020 09:59
> To: paul@xen.org
> Cc: xen-devel@lists.xenproject.org; Paul Durrant <pdurrant@amazon.com>; Andrew Cooper
> <andrew.cooper3@citrix.com>; George Dunlap <george.dunlap@citrix.com>; Wei Liu <wl@xen.org>; Roger Pau
> Monné <roger.pau@citrix.com>
> Subject: Re: [PATCH v4 2/6] x86 / p2m: remove page_list check in p2m_alloc_table...
>
> On 09.03.2020 10:35, paul@xen.org wrote:
> > From: Paul Durrant <pdurrant@amazon.com>
> >
> > ... and replace with a check of domain_tot_pages().
> >
> > The check of page_list prevents the prior allocation of PGC_extra pages,
> > whereas what the code is trying to verify is that the toolstack has not
> > already RAM for the domain.
> >
> > Signed-off-by: Paul Durrant <paul@xen.org>
>
> Reviewed-by: Jan Beulich <jbeulich@suse.com>
Thnaks.
> preferably with "remove" in the subject replaced by the "replace"
> currently at the beginning of the description. (It also looks as
> if there was "allocated" or some such missing near the end of the
> description.)
>
Ok, I'll fix in v5.
Paul
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xenproject.org
https://lists.xenproject.org/mailman/listinfo/xen-devel
^ permalink raw reply [flat|nested] 10+ messages in thread
end of thread, other threads:[~2020-03-09 10:08 UTC | newest]
Thread overview: 10+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-03-09 9:35 [Xen-devel] [PATCH v4 0/6] remove one more shared xenheap page: shared_info paul
2020-03-09 9:35 ` [Xen-devel] [PATCH v4 1/6] domain: introduce alloc/free_shared_info() helpers paul
2020-03-09 9:35 ` [Xen-devel] [PATCH v4 2/6] x86 / p2m: remove page_list check in p2m_alloc_table paul
2020-03-09 9:59 ` Jan Beulich
2020-03-09 10:07 ` Paul Durrant
2020-03-09 9:35 ` [Xen-devel] [PATCH v4 3/6] x86 / pv: do not treat PGC_extra pages as RAM paul
2020-03-09 9:35 ` [Xen-devel] [PATCH v4 4/6] x86 / ioreq: use a MEMF_no_refcount allocation for server pages paul
2020-03-09 9:35 ` [Xen-devel] [PATCH v4 5/6] mm: add 'is_special_page' inline function paul
2020-03-09 9:35 ` [Xen-devel] [PATCH v4 6/6] domain: use PGC_extra domheap page for shared_info paul
2020-03-09 10:00 ` Durrant, Paul
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).