[PATCH v2 6/7] x86/virt/tdx: Use ida_is_empty() to detect if any TDs may be running

Sean Christopherson
2025-12-06T01:11:19Z

Drop nr_configured_hkid and instead use ida_is_empty() to detect if any
HKIDs have been allocated/configured.

Suggested-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
---
arch/x86/virt/vmx/tdx/tdx.c | 17 ++++-------------
1 file changed, 4 insertions(+), 13 deletions(-)

diff --git a/arch/x86/virt/vmx/tdx/tdx.c b/arch/x86/virt/vmx/tdx/tdx.c
index 5cf008bffa94..ef77135ec373 100644
--- a/arch/x86/virt/vmx/tdx/tdx.c
+++ b/arch/x86/virt/vmx/tdx/tdx.c
@@ -58,8 +58,6 @@ static LIST_HEAD(tdx_memlist);
static struct tdx_sys_info tdx_sysinfo __ro_after_init;
static bool tdx_module_initialized __ro_after_init;

-static atomic_t nr_configured_hkid;
-
typedef void (*sc_err_func_t)(u64 fn, u64 err, struct tdx_module_args *args);

static inline void seamcall_err(u64 fn, u64 err, struct tdx_module_args *args)
@@ -195,7 +193,7 @@ static int tdx_offline_cpu(unsigned int cpu)
int i;

/* No TD is running. Allow any cpu to be offline. */
- if (!atomic_read(&nr_configured_hkid))
+ if (ida_is_empty(&tdx_guest_keyid_pool))
goto done;

/*
@@ -1542,22 +1540,15 @@ EXPORT_SYMBOL_GPL(tdx_get_nr_guest_keyids);

int tdx_guest_keyid_alloc(void)
{
- int ret;
-
- ret = ida_alloc_range(&tdx_guest_keyid_pool, tdx_guest_keyid_start,
- tdx_guest_keyid_start + tdx_nr_guest_keyids - 1,
- GFP_KERNEL);
- if (ret >= 0)
- atomic_inc(&nr_configured_hkid);
-
- return ret;
+ return ida_alloc_range(&tdx_guest_keyid_pool, tdx_guest_keyid_start,
+ tdx_guest_keyid_start + tdx_nr_guest_keyids - 1,
+ GFP_KERNEL);
}
EXPORT_SYMBOL_GPL(tdx_guest_keyid_alloc);

void tdx_guest_keyid_free(unsigned int keyid)
{
ida_free(&tdx_guest_keyid_pool, keyid);
- atomic_dec(&nr_configured_hkid);
}
EXPORT_SYMBOL_GPL(tdx_guest_keyid_free);

--
2.52.0.223.gf5cc29aaa4-goog