Merge branch 'locking/urgent'

Sync with urgent -- avoid conflicts.

Signed-off-by: Peter Zijlstra <peterz@infradead.org>

5 files changed, 34 insertions, 17 deletions

diff --git a/lib/alloc_tag.c b/lib/alloc_tag.c
index 2414a7ee7ec77..35f7560a309a4 100644
--- a/lib/alloc_tag.c
+++ b/lib/alloc_tag.c
@@ -189,26 +189,34 @@ void pgalloc_tag_split(struct folio *folio, int old_order, int new_order)
 	}
 }
 
-void pgalloc_tag_copy(struct folio *new, struct folio *old)
+void pgalloc_tag_swap(struct folio *new, struct folio *old)
 {
-	union pgtag_ref_handle handle;
-	union codetag_ref ref;
-	struct alloc_tag *tag;
+	union pgtag_ref_handle handle_old, handle_new;
+	union codetag_ref ref_old, ref_new;
+	struct alloc_tag *tag_old, *tag_new;
 
-	tag = pgalloc_tag_get(&old->page);
-	if (!tag)
+	tag_old = pgalloc_tag_get(&old->page);
+	if (!tag_old)
+		return;
+	tag_new = pgalloc_tag_get(&new->page);
+	if (!tag_new)
 		return;
 
-	if (!get_page_tag_ref(&new->page, &ref, &handle))
+	if (!get_page_tag_ref(&old->page, &ref_old, &handle_old))
 		return;
+	if (!get_page_tag_ref(&new->page, &ref_new, &handle_new)) {
+		put_page_tag_ref(handle_old);
+		return;
+	}
+
+	/* swap tags */
+	__alloc_tag_ref_set(&ref_old, tag_new);
+	update_page_tag_ref(handle_old, &ref_old);
+	__alloc_tag_ref_set(&ref_new, tag_old);
+	update_page_tag_ref(handle_new, &ref_new);
 
-	/* Clear the old ref to the original allocation tag. */
-	clear_page_tag_ref(&old->page);
-	/* Decrement the counters of the tag on get_new_folio. */
-	alloc_tag_sub(&ref, folio_size(new));
-	__alloc_tag_ref_set(&ref, tag);
-	update_page_tag_ref(handle, &ref);
-	put_page_tag_ref(handle);
+	put_page_tag_ref(handle_old);
+	put_page_tag_ref(handle_new);
 }
 
 static void shutdown_mem_profiling(bool remove_file)
diff --git a/lib/kunit/user_alloc.c b/lib/kunit/user_alloc.c
index ae935df09a5eb..46951be018be2 100644
--- a/lib/kunit/user_alloc.c
+++ b/lib/kunit/user_alloc.c
@@ -114,4 +114,4 @@ unsigned long kunit_vm_mmap(struct kunit *test, struct file *file,
 }
 EXPORT_SYMBOL_GPL(kunit_vm_mmap);
 
-MODULE_IMPORT_NS(EXPORTED_FOR_KUNIT_TESTING);
+MODULE_IMPORT_NS("EXPORTED_FOR_KUNIT_TESTING");
diff --git a/lib/stackdepot.c b/lib/stackdepot.c
index 5ed34cc963fc3..245d5b4166999 100644
--- a/lib/stackdepot.c
+++ b/lib/stackdepot.c
@@ -630,7 +630,15 @@ depot_stack_handle_t stack_depot_save_flags(unsigned long *entries,
 			prealloc = page_address(page);
 	}
 
-	raw_spin_lock_irqsave(&pool_lock, flags);
+	if (in_nmi()) {
+		/* We can never allocate in NMI context. */
+		WARN_ON_ONCE(can_alloc);
+		/* Best effort; bail if we fail to take the lock. */
+		if (!raw_spin_trylock_irqsave(&pool_lock, flags))
+			goto exit;
+	} else {
+		raw_spin_lock_irqsave(&pool_lock, flags);
+	}
 	printk_deferred_enter();
 
 	/* Try to find again, to avoid concurrently inserting duplicates. */
diff --git a/lib/stackinit_kunit.c b/lib/stackinit_kunit.c
index c14c6f8e6308d..c40818ec9c180 100644
--- a/lib/stackinit_kunit.c
+++ b/lib/stackinit_kunit.c
@@ -212,6 +212,7 @@ static noinline void test_ ## name (struct kunit *test)		\
 static noinline DO_NOTHING_TYPE_ ## which(var_type)		\
 do_nothing_ ## name(var_type *ptr)				\
 {								\
+	OPTIMIZER_HIDE_VAR(ptr);				\
 	/* Will always be true, but compiler doesn't know. */	\
 	if ((unsigned long)ptr > 0x2)				\
 		return DO_NOTHING_RETURN_ ## which(ptr);	\
diff --git a/lib/test_firmware.c b/lib/test_firmware.c
index bcb32cbff1885..211222e63328f 100644
--- a/lib/test_firmware.c
+++ b/lib/test_firmware.c
@@ -27,7 +27,7 @@
 #include <linux/vmalloc.h>
 #include <linux/efi_embedded_fw.h>
 
-MODULE_IMPORT_NS(TEST_FIRMWARE);
+MODULE_IMPORT_NS("TEST_FIRMWARE");
 
 #define TEST_FIRMWARE_NAME	"test-firmware.bin"
 #define TEST_FIRMWARE_NUM_REQS	4