lib: sbi_domain: add TSA annotations

Add Thread Safety Analysis (TSA) annotations for the domain handling
code. This includes indicating which fields are protected by a spinlock,
and annotating which functions acquire a spinlock, in order to prevent
nesting. Exclude sbi_domain_register() from analysis, as it initializes
a domain's spinlock.

Signed-off-by: Carlos López <carlos.lopezr4096@gmail.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Link: https://lore.kernel.org/r/20260909162322.29778-11-carlos.lopezr4096@gmail.com
Signed-off-by: Anup Patel <anup@brainfault.org>

include/sbi/sbi_domain.h

@@ -193,10 +193,10 @@ struct sbi_domain {
 	struct sbi_domain_state_priv state_priv;
 	/** Logical index of this domain */
 	u32 index;
-	/** HARTs assigned to this domain */
-	struct sbi_hartmask assigned_harts;
 	/** Spinlock for accessing assigned_harts */
 	spinlock_t assigned_harts_lock;
+	/** HARTs assigned to this domain */
+	struct sbi_hartmask assigned_harts GUARDED_BY(&assigned_harts_lock);
 	/** Name of this domain */
 	char name[64];
 	/** Initialization order of this domain */
@@ -254,7 +254,8 @@ extern struct sbi_dlist domain_list;
  * @param hartindex the HART index
  * @return true if HART is assigned to domain otherwise false
  */
-bool sbi_domain_is_assigned_hart(const struct sbi_domain *dom, u32 hartindex);
+bool sbi_domain_is_assigned_hart(const struct sbi_domain *dom, u32 hartindex)
+	MUST_NOT_HOLD(&dom->assigned_harts_lock);
 
 /**
  * Get the assigned HART mask for given domain
@@ -263,7 +264,8 @@ bool sbi_domain_is_assigned_hart(const struct sbi_domain *dom, u32 hartindex);
  * @return 0 on success and SBI_Exxx (< 0) on failure
  */
 int sbi_domain_get_assigned_hartmask(const struct sbi_domain *dom,
-				     struct sbi_hartmask *mask);
+				     struct sbi_hartmask *mask)
+	MUST_NOT_HOLD(&dom->assigned_harts_lock);
 
 /**
  * Initialize a domain memory region based on it's physical

lib/sbi/sbi_domain.c

@@ -61,6 +61,7 @@ void sbi_update_hartindex_to_domain(u32 hartindex, struct sbi_domain *dom)
 }
 
 bool sbi_domain_is_assigned_hart(const struct sbi_domain *dom, u32 hartindex)
+	MUST_NOT_HOLD(&dom->assigned_harts_lock)
 {
 	bool ret;
 	struct sbi_domain *tdom = (struct sbi_domain *)dom;
@@ -77,6 +78,7 @@ bool sbi_domain_is_assigned_hart(const struct sbi_domain *dom, u32 hartindex)
 
 int sbi_domain_get_assigned_hartmask(const struct sbi_domain *dom,
 				     struct sbi_hartmask *mask)
+	MUST_NOT_HOLD(&dom->assigned_harts_lock)
 {
 	ulong ret = 0;
 	struct sbi_domain *tdom = (struct sbi_domain *)dom;
@@ -630,6 +632,7 @@ void sbi_domain_dump_all(const char *suffix)
 }
 
 int sbi_domain_register(struct sbi_domain *dom)
+	NO_THREAD_SAFETY_ANALYSIS
 {
 	u32 i, cold_hartid = current_hartid();
 	struct sbi_domain *tdom;

lib/sbi/sbi_domain_context.c

@@ -107,6 +107,8 @@ static void hart_context_set(struct sbi_domain *dom, u32 hartindex,
  */
 static int switch_to_next_domain_context(struct hart_context *ctx,
 					  struct hart_context *dom_ctx)
+	MUST_NOT_HOLD(&ctx->dom->assigned_harts_lock)
+	MUST_NOT_HOLD(&dom_ctx->dom->assigned_harts_lock)
 {
 	u32 hartindex = current_hartindex();
 	struct sbi_trap_context *trap_ctx;