tools/libs/light/libxl_create.c | 4 +++- tools/tests/domid/harness.h | 1 + tools/tests/domid/test-domid.c | 12 ++++++------ tools/tests/mem-claim/test-mem-claim.c | 6 +++--- tools/tests/paging-mempool/test-paging-mempool.c | 2 +- tools/tests/resource/test-resource.c | 2 +- tools/tests/tsx/test-tsx.c | 2 +- xen/common/device-tree/dom0less-build.c | 2 +- xen/common/domctl.c | 3 +-- xen/common/domid.c | 5 ++++- xen/include/public/xen.h | 7 +++++++ 11 files changed, 29 insertions(+), 17 deletions(-)
From: Denis Mukhin <dmukhin@ford.com>
Add a new symbol DOMID_ANY to improve the readability of the code.
Update all relevant domid_alloc() call sites and harden the domid_alloc()
input value check.
Also, fix problem with passing invalid domain IDs in
XEN_DOMCTL_createdomain: turns out libxl__domain_make() (toolstack)
uses 0xffff as domain ID.
Fix failing tools tests too.
Amends: 2d5065060710 ("xen/domain: unify domain ID allocation")
Signed-off-by: Denis Mukhin <dmukhin@ford.com>
---
Changes since v7:
- aligned the DOMID_ANY comment with another patch sent separately to
unblock xenstore series: https://lore.kernel.org/xen-devel/20260429120619.1013440-2-jgross@suse.com/
- added fixups to mem-claim, paging-mempool, resource and tsx tests.
- Link to v7: https://lore.kernel.org/xen-devel/20260408234046.1314021-1-dmukhin@ford.com/
- Link to full CI: https://gitlab.com/xen-project/people/sstabellini/xen/-/pipelines/2508345752
---
tools/libs/light/libxl_create.c | 4 +++-
tools/tests/domid/harness.h | 1 +
tools/tests/domid/test-domid.c | 12 ++++++------
tools/tests/mem-claim/test-mem-claim.c | 6 +++---
tools/tests/paging-mempool/test-paging-mempool.c | 2 +-
tools/tests/resource/test-resource.c | 2 +-
tools/tests/tsx/test-tsx.c | 2 +-
xen/common/device-tree/dom0less-build.c | 2 +-
xen/common/domctl.c | 3 +--
xen/common/domid.c | 5 ++++-
xen/include/public/xen.h | 7 +++++++
11 files changed, 29 insertions(+), 17 deletions(-)
diff --git a/tools/libs/light/libxl_create.c b/tools/libs/light/libxl_create.c
index bfc9149096a3..6fd62d140389 100644
--- a/tools/libs/light/libxl_create.c
+++ b/tools/libs/light/libxl_create.c
@@ -681,8 +681,10 @@ int libxl__domain_make(libxl__gc *gc, libxl_domain_config *d_config,
continue;
local_domid = v;
+ } else if (libxl_domid_valid_guest(info->domid)) {
+ local_domid = info->domid;
} else {
- local_domid = info->domid; /* May not be valid */
+ local_domid = DOMID_ANY;
}
ret = xc_domain_create(ctx->xch, &local_domid, &create);
diff --git a/tools/tests/domid/harness.h b/tools/tests/domid/harness.h
index 17eb22a9a854..65da0d075a2b 100644
--- a/tools/tests/domid/harness.h
+++ b/tools/tests/domid/harness.h
@@ -41,6 +41,7 @@ extern unsigned long find_next_zero_bit(const unsigned long *addr,
#define DOMID_FIRST_RESERVED (100)
#define DOMID_INVALID (101)
+#define DOMID_ANY (102)
#endif /* _TEST_HARNESS_ */
diff --git a/tools/tests/domid/test-domid.c b/tools/tests/domid/test-domid.c
index 5915c4699a5c..71cc4e7fd86d 100644
--- a/tools/tests/domid/test-domid.c
+++ b/tools/tests/domid/test-domid.c
@@ -41,20 +41,20 @@ int main(int argc, char **argv)
domid_free(expected);
/*
- * Test that that two consecutive calls of domid_alloc(DOMID_INVALID)
+ * Test that that two consecutive calls of domid_alloc(DOMID_ANY)
* will never return the same ID.
* NB: ID#0 is reserved and shall not be allocated by
- * domid_alloc(DOMID_INVALID).
+ * domid_alloc(DOMID_ANY).
*/
for ( expected = 1; expected < DOMID_FIRST_RESERVED; expected++ )
{
- allocated = domid_alloc(DOMID_INVALID);
+ allocated = domid_alloc(DOMID_ANY);
verify(allocated == expected,
"TEST 3: expected %u allocated %u\n", expected, allocated);
}
for ( expected = 1; expected < DOMID_FIRST_RESERVED; expected++ )
{
- allocated = domid_alloc(DOMID_INVALID);
+ allocated = domid_alloc(DOMID_ANY);
verify(allocated == DOMID_INVALID,
"TEST 4: expected %u allocated %u\n", DOMID_INVALID, allocated);
}
@@ -64,7 +64,7 @@ int main(int argc, char **argv)
domid_free(expected);
for ( expected = 1; expected < DOMID_FIRST_RESERVED / 2; expected++ )
{
- allocated = domid_alloc(DOMID_INVALID);
+ allocated = domid_alloc(DOMID_ANY);
verify(allocated == expected,
"TEST 5: expected %u allocated %u\n", expected, allocated);
}
@@ -72,7 +72,7 @@ int main(int argc, char **argv)
/* Re-allocate last ID from [1..DOMID_FIRST_RESERVED - 1]. */
expected = DOMID_FIRST_RESERVED - 1;
domid_free(DOMID_FIRST_RESERVED - 1);
- allocated = domid_alloc(DOMID_INVALID);
+ allocated = domid_alloc(DOMID_ANY);
verify(allocated == expected,
"TEST 6: expected %u allocated %u\n", expected, allocated);
diff --git a/tools/tests/mem-claim/test-mem-claim.c b/tools/tests/mem-claim/test-mem-claim.c
index ad038e45d188..69dc99cfdd51 100644
--- a/tools/tests/mem-claim/test-mem-claim.c
+++ b/tools/tests/mem-claim/test-mem-claim.c
@@ -21,7 +21,7 @@ static unsigned int nr_failures;
#define MB_PAGES(x) (MB(x) / XC_PAGE_SIZE)
static xc_interface *xch;
-static uint32_t domid = DOMID_INVALID;
+static uint32_t domid = DOMID_ANY;
static xc_physinfo_t physinfo;
@@ -142,7 +142,7 @@ static void run_tests(void)
rc = xc_domain_destroy(xch, domid);
/* Cancel the cleanup path, even in the case of an error. */
- domid = DOMID_INVALID;
+ domid = DOMID_ANY;
if ( rc )
return fail(" Failed to destroy domain: %d - %s\n",
@@ -171,7 +171,7 @@ int main(int argc, char **argv)
run_tests();
- if ( domid != DOMID_INVALID )
+ if ( domid != DOMID_ANY )
{
rc = xc_domain_destroy(xch, domid);
if ( rc )
diff --git a/tools/tests/paging-mempool/test-paging-mempool.c b/tools/tests/paging-mempool/test-paging-mempool.c
index 1ebc13455ac2..7e417d9798ac 100644
--- a/tools/tests/paging-mempool/test-paging-mempool.c
+++ b/tools/tests/paging-mempool/test-paging-mempool.c
@@ -18,7 +18,7 @@ static unsigned int nr_failures;
})
static xc_interface *xch;
-static uint32_t domid;
+static uint32_t domid = DOMID_ANY;
static struct xen_domctl_createdomain create = {
.flags = XEN_DOMCTL_CDF_hvm | XEN_DOMCTL_CDF_hap,
diff --git a/tools/tests/resource/test-resource.c b/tools/tests/resource/test-resource.c
index a7f2d0464326..236da0dcd45e 100644
--- a/tools/tests/resource/test-resource.c
+++ b/tools/tests/resource/test-resource.c
@@ -178,7 +178,7 @@ static void test_domain_configurations(void)
for ( unsigned int i = 0; i < ARRAY_SIZE(tests); ++i )
{
struct test *t = &tests[i];
- uint32_t domid = 0;
+ uint32_t domid = DOMID_ANY;
int rc;
xen_pfn_t ram[1] = { 0 };
diff --git a/tools/tests/tsx/test-tsx.c b/tools/tests/tsx/test-tsx.c
index 5af04953f340..ea7c03ad302e 100644
--- a/tools/tests/tsx/test-tsx.c
+++ b/tools/tests/tsx/test-tsx.c
@@ -362,7 +362,7 @@ static void test_def_max_policies(void)
static void test_guest(struct xen_domctl_createdomain *c)
{
- uint32_t domid = 0;
+ uint32_t domid = DOMID_ANY;
int rc;
rc = xc_domain_create(xch, &domid, c);
diff --git a/xen/common/device-tree/dom0less-build.c b/xen/common/device-tree/dom0less-build.c
index 6d6882a34b5a..eacfd93087ae 100644
--- a/xen/common/device-tree/dom0less-build.c
+++ b/xen/common/device-tree/dom0less-build.c
@@ -871,7 +871,7 @@ void __init create_domUs(void)
if ( (max_init_domid + 1) >= DOMID_FIRST_RESERVED )
panic("No more domain IDs available\n");
- domid = domid_alloc(DOMID_INVALID);
+ domid = domid_alloc(DOMID_ANY);
if ( domid == DOMID_INVALID )
panic("Error allocating ID for domain %s\n", dt_node_name(node));
diff --git a/xen/common/domctl.c b/xen/common/domctl.c
index 93738931c575..b969f5ada6cc 100644
--- a/xen/common/domctl.c
+++ b/xen/common/domctl.c
@@ -409,8 +409,7 @@ long do_domctl(XEN_GUEST_HANDLE_PARAM(xen_domctl_t) u_domctl)
case XEN_DOMCTL_createdomain:
{
- /* NB: ID#0 is reserved, find the first suitable ID instead. */
- domid_t domid = domid_alloc(op->domain ?: DOMID_INVALID);
+ domid_t domid = domid_alloc(op->domain);
if ( domid == DOMID_INVALID )
{
diff --git a/xen/common/domid.c b/xen/common/domid.c
index 2387ddb08300..b0258e477c1a 100644
--- a/xen/common/domid.c
+++ b/xen/common/domid.c
@@ -19,7 +19,7 @@ static DECLARE_BITMAP(domid_bitmap, DOMID_FIRST_RESERVED);
* @param domid Domain ID hint:
* - If an explicit domain ID is provided, verify its availability and use it
* if ID is not used;
- * - If DOMID_INVALID is provided, search [1..DOMID_FIRST_RESERVED-1] range,
+ * - If DOMID_ANY is provided, search [1..DOMID_FIRST_RESERVED-1] range,
* starting from the last used ID. Implementation guarantees that two
* consecutive calls will never return the same ID. ID#0 is reserved for
* the first boot domain (currently, dom0) and excluded from the allocation
@@ -31,6 +31,9 @@ domid_t domid_alloc(domid_t domid)
{
static domid_t domid_last;
+ if ( domid >= DOMID_FIRST_RESERVED && domid != DOMID_ANY )
+ return DOMID_INVALID;
+
spin_lock(&domid_lock);
/* Exact match. */
diff --git a/xen/include/public/xen.h b/xen/include/public/xen.h
index b12fd10e6315..2149b8dd3808 100644
--- a/xen/include/public/xen.h
+++ b/xen/include/public/xen.h
@@ -608,6 +608,13 @@ DEFINE_XEN_GUEST_HANDLE(mmuext_op_t);
/* DOMID_INVALID is used to identify pages with unknown owner. */
#define DOMID_INVALID xen_mk_uint(0x7FF4)
+/*
+ * DOMID_ANY is used to signal no specific domain ID requested.
+ * Handler should pick a valid ID, or handle it as a wildcard value
+ * depending on the context.
+ */
+#define DOMID_ANY xen_mk_uint(0x7FF5)
+
/* Idle domain. */
#define DOMID_IDLE xen_mk_uint(0x7FFF)
--
2.54.0On Thu, May 07, 2026 at 01:28:40PM -0700, dmukhin@ford.com wrote:
> From: Denis Mukhin <dmukhin@ford.com>
>
> Add a new symbol DOMID_ANY to improve the readability of the code.
>
> Update all relevant domid_alloc() call sites and harden the domid_alloc()
> input value check.
>
> Also, fix problem with passing invalid domain IDs in
> XEN_DOMCTL_createdomain: turns out libxl__domain_make() (toolstack)
> uses 0xffff as domain ID.
>
> Fix failing tools tests too.
>
> Amends: 2d5065060710 ("xen/domain: unify domain ID allocation")
> Signed-off-by: Denis Mukhin <dmukhin@ford.com>
> ---
> Changes since v7:
> - aligned the DOMID_ANY comment with another patch sent separately to
> unblock xenstore series: https://lore.kernel.org/xen-devel/20260429120619.1013440-2-jgross@suse.com/
> - added fixups to mem-claim, paging-mempool, resource and tsx tests.
> - Link to v7: https://lore.kernel.org/xen-devel/20260408234046.1314021-1-dmukhin@ford.com/
> - Link to full CI: https://gitlab.com/xen-project/people/sstabellini/xen/-/pipelines/2508345752
For the tools part:
Reviewed-by: Anthony PERARD <anthony.perard@vates.tech>
Thanks,
--
Anthony Perard | Vates XCP-ng Developer
XCP-ng & Xen Orchestra - Vates solutions
web: https://vates.tech
This patch has been around for a long time and has gone through the
ci-loop multiple times. I think it is low risk.
Oleksii, can we have a release ack for this?
On Wed, 13 May 2026, Anthony PERARD wrote:
> On Thu, May 07, 2026 at 01:28:40PM -0700, dmukhin@ford.com wrote:
> > From: Denis Mukhin <dmukhin@ford.com>
> >
> > Add a new symbol DOMID_ANY to improve the readability of the code.
> >
> > Update all relevant domid_alloc() call sites and harden the domid_alloc()
> > input value check.
> >
> > Also, fix problem with passing invalid domain IDs in
> > XEN_DOMCTL_createdomain: turns out libxl__domain_make() (toolstack)
> > uses 0xffff as domain ID.
> >
> > Fix failing tools tests too.
> >
> > Amends: 2d5065060710 ("xen/domain: unify domain ID allocation")
> > Signed-off-by: Denis Mukhin <dmukhin@ford.com>
> > ---
> > Changes since v7:
> > - aligned the DOMID_ANY comment with another patch sent separately to
> > unblock xenstore series: https://lore.kernel.org/xen-devel/20260429120619.1013440-2-jgross@suse.com/
> > - added fixups to mem-claim, paging-mempool, resource and tsx tests.
> > - Link to v7: https://lore.kernel.org/xen-devel/20260408234046.1314021-1-dmukhin@ford.com/
> > - Link to full CI: https://gitlab.com/xen-project/people/sstabellini/xen/-/pipelines/2508345752
>
> For the tools part:
> Reviewed-by: Anthony PERARD <anthony.perard@vates.tech>
>
> Thanks,
>
>
> --
> Anthony Perard | Vates XCP-ng Developer
>
> XCP-ng & Xen Orchestra - Vates solutions
>
> web: https://vates.tech
On 5/15/26 11:25 PM, Stefano Stabellini wrote:
> This patch has been around for a long time and has gone through the
> ci-loop multiple times. I think it is low risk.
>
> Oleksii, can we have a release ack for this?
It looks low risk so we can consider to have it in 4.22:
Release-Acked-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
Thanks.
~ Oleksii
>
>
> On Wed, 13 May 2026, Anthony PERARD wrote:
>> On Thu, May 07, 2026 at 01:28:40PM -0700, dmukhin@ford.com wrote:
>>> From: Denis Mukhin <dmukhin@ford.com>
>>>
>>> Add a new symbol DOMID_ANY to improve the readability of the code.
>>>
>>> Update all relevant domid_alloc() call sites and harden the domid_alloc()
>>> input value check.
>>>
>>> Also, fix problem with passing invalid domain IDs in
>>> XEN_DOMCTL_createdomain: turns out libxl__domain_make() (toolstack)
>>> uses 0xffff as domain ID.
>>>
>>> Fix failing tools tests too.
>>>
>>> Amends: 2d5065060710 ("xen/domain: unify domain ID allocation")
>>> Signed-off-by: Denis Mukhin <dmukhin@ford.com>
>>> ---
>>> Changes since v7:
>>> - aligned the DOMID_ANY comment with another patch sent separately to
>>> unblock xenstore series: https://lore.kernel.org/xen-devel/20260429120619.1013440-2-jgross@suse.com/
>>> - added fixups to mem-claim, paging-mempool, resource and tsx tests.
>>> - Link to v7: https://lore.kernel.org/xen-devel/20260408234046.1314021-1-dmukhin@ford.com/
>>> - Link to full CI: https://gitlab.com/xen-project/people/sstabellini/xen/-/pipelines/2508345752
>>
>> For the tools part:
>> Reviewed-by: Anthony PERARD <anthony.perard@vates.tech>
>>
>> Thanks,
>>
>>
>> --
>> Anthony Perard | Vates XCP-ng Developer
>>
>> XCP-ng & Xen Orchestra - Vates solutions
>>
>> web: https://vates.tech
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