diff --git a/src/crypto/tls/tls.go b/src/crypto/tls/tls.go
index a389873d32e..4989364958e 100644
--- a/src/crypto/tls/tls.go
+++ b/src/crypto/tls/tls.go
@@ -111,6 +111,9 @@ func (timeoutError) Temporary() bool { return true }
 //
 // DialWithDialer interprets a nil configuration as equivalent to the zero
 // configuration; see the documentation of Config for the defaults.
+//
+// DialWithDialer uses context.Background internally; to specify the context,
+// use Dialer.DialContext with NetDialer set to the desired dialer.
 func DialWithDialer(dialer *net.Dialer, network, addr string, config *Config) (*Conn, error) {
 	return dial(context.Background(), dialer, network, addr, config)
 }
@@ -224,6 +227,9 @@ type Dialer struct {
 // handshake, returning the resulting TLS connection.
 //
 // The returned Conn, if any, will always be of type *Conn.
+//
+// Dial uses context.Background internally; to specify the context,
+// use DialContext.
 func (d *Dialer) Dial(network, addr string) (net.Conn, error) {
 	return d.DialContext(context.Background(), network, addr)
 }
diff --git a/src/database/sql/sql.go b/src/database/sql/sql.go
index 37bcb0d0918..12cc524c632 100644
--- a/src/database/sql/sql.go
+++ b/src/database/sql/sql.go
@@ -813,6 +813,9 @@ func (db *DB) PingContext(ctx context.Context) error {
 
 // Ping verifies a connection to the database is still alive,
 // establishing a connection if necessary.
+//
+// Ping uses context.Background internally; to specify the context, use
+// PingContext.
 func (db *DB) Ping() error {
 	return db.PingContext(context.Background())
 }
@@ -1481,6 +1484,9 @@ func (db *DB) PrepareContext(ctx context.Context, query string) (*Stmt, error) {
 // returned statement.
 // The caller must call the statement's Close method
 // when the statement is no longer needed.
+//
+// Prepare uses context.Background internally; to specify the context, use
+// PrepareContext.
 func (db *DB) Prepare(query string) (*Stmt, error) {
 	return db.PrepareContext(context.Background(), query)
 }
@@ -1551,6 +1557,9 @@ func (db *DB) ExecContext(ctx context.Context, query string, args ...interface{}
 
 // Exec executes a query without returning any rows.
 // The args are for any placeholder parameters in the query.
+//
+// Exec uses context.Background internally; to specify the context, use
+// ExecContext.
 func (db *DB) Exec(query string, args ...interface{}) (Result, error) {
 	return db.ExecContext(context.Background(), query, args...)
 }
@@ -1621,6 +1630,9 @@ func (db *DB) QueryContext(ctx context.Context, query string, args ...interface{
 
 // Query executes a query that returns rows, typically a SELECT.
 // The args are for any placeholder parameters in the query.
+//
+// Query uses context.Background internally; to specify the context, use
+// QueryContext.
 func (db *DB) Query(query string, args ...interface{}) (*Rows, error) {
 	return db.QueryContext(context.Background(), query, args...)
 }
@@ -1719,6 +1731,9 @@ func (db *DB) QueryRowContext(ctx context.Context, query string, args ...interfa
 // If the query selects no rows, the *Row's Scan will return ErrNoRows.
 // Otherwise, the *Row's Scan scans the first selected row and discards
 // the rest.
+//
+// QueryRow uses context.Background internally; to specify the context, use
+// QueryRowContext.
 func (db *DB) QueryRow(query string, args ...interface{}) *Row {
 	return db.QueryRowContext(context.Background(), query, args...)
 }
@@ -1750,6 +1765,9 @@ func (db *DB) BeginTx(ctx context.Context, opts *TxOptions) (*Tx, error) {
 
 // Begin starts a transaction. The default isolation level is dependent on
 // the driver.
+//
+// Begin uses context.Background internally; to specify the context, use
+// BeginTx.
 func (db *DB) Begin() (*Tx, error) {
 	return db.BeginTx(context.Background(), nil)
 }
@@ -2255,6 +2273,9 @@ func (tx *Tx) PrepareContext(ctx context.Context, query string) (*Stmt, error) {
 // be used once the transaction has been committed or rolled back.
 //
 // To use an existing prepared statement on this transaction, see Tx.Stmt.
+//
+// Prepare uses context.Background internally; to specify the context, use
+// PrepareContext.
 func (tx *Tx) Prepare(query string) (*Stmt, error) {
 	return tx.PrepareContext(context.Background(), query)
 }
@@ -2358,6 +2379,9 @@ func (tx *Tx) StmtContext(ctx context.Context, stmt *Stmt) *Stmt {
 //
 // The returned statement operates within the transaction and will be closed
 // when the transaction has been committed or rolled back.
+//
+// Stmt uses context.Background internally; to specify the context, use
+// StmtContext.
 func (tx *Tx) Stmt(stmt *Stmt) *Stmt {
 	return tx.StmtContext(context.Background(), stmt)
 }
@@ -2374,6 +2398,9 @@ func (tx *Tx) ExecContext(ctx context.Context, query string, args ...interface{}
 
 // Exec executes a query that doesn't return rows.
 // For example: an INSERT and UPDATE.
+//
+// Exec uses context.Background internally; to specify the context, use
+// ExecContext.
 func (tx *Tx) Exec(query string, args ...interface{}) (Result, error) {
 	return tx.ExecContext(context.Background(), query, args...)
 }
@@ -2389,6 +2416,9 @@ func (tx *Tx) QueryContext(ctx context.Context, query string, args ...interface{
 }
 
 // Query executes a query that returns rows, typically a SELECT.
+//
+// Query uses context.Background internally; to specify the context, use
+// QueryContext.
 func (tx *Tx) Query(query string, args ...interface{}) (*Rows, error) {
 	return tx.QueryContext(context.Background(), query, args...)
 }
@@ -2410,6 +2440,9 @@ func (tx *Tx) QueryRowContext(ctx context.Context, query string, args ...interfa
 // If the query selects no rows, the *Row's Scan will return ErrNoRows.
 // Otherwise, the *Row's Scan scans the first selected row and discards
 // the rest.
+//
+// QueryRow uses context.Background internally; to specify the context, use
+// QueryRowContext.
 func (tx *Tx) QueryRow(query string, args ...interface{}) *Row {
 	return tx.QueryRowContext(context.Background(), query, args...)
 }
@@ -2516,6 +2549,9 @@ func (s *Stmt) ExecContext(ctx context.Context, args ...interface{}) (Result, er
 
 // Exec executes a prepared statement with the given arguments and
 // returns a Result summarizing the effect of the statement.
+//
+// Exec uses context.Background internally; to specify the context, use
+// ExecContext.
 func (s *Stmt) Exec(args ...interface{}) (Result, error) {
 	return s.ExecContext(context.Background(), args...)
 }
@@ -2687,6 +2723,9 @@ func (s *Stmt) QueryContext(ctx context.Context, args ...interface{}) (*Rows, er
 
 // Query executes a prepared query statement with the given arguments
 // and returns the query results as a *Rows.
+//
+// Query uses context.Background internally; to specify the context, use
+// QueryContext.
 func (s *Stmt) Query(args ...interface{}) (*Rows, error) {
 	return s.QueryContext(context.Background(), args...)
 }
@@ -2726,6 +2765,9 @@ func (s *Stmt) QueryRowContext(ctx context.Context, args ...interface{}) *Row {
 //
 //  var name string
 //  err := nameByUseridStmt.QueryRow(id).Scan(&name)
+//
+// QueryRow uses context.Background internally; to specify the context, use
+// QueryRowContext.
 func (s *Stmt) QueryRow(args ...interface{}) *Row {
 	return s.QueryRowContext(context.Background(), args...)
 }
diff --git a/src/net/dial.go b/src/net/dial.go
index 13a312a91ae..486ced0f2a9 100644
--- a/src/net/dial.go
+++ b/src/net/dial.go
@@ -344,6 +344,9 @@ type sysDialer struct {
 //
 // See func Dial for a description of the network and address
 // parameters.
+//
+// Dial uses context.Background internally; to specify the context, use
+// DialContext.
 func (d *Dialer) Dial(network, address string) (Conn, error) {
 	return d.DialContext(context.Background(), network, address)
 }
@@ -701,6 +704,9 @@ type sysListener struct {
 //
 // See func Dial for a description of the network and address
 // parameters.
+//
+// Listen uses context.Background internally; to specify the context, use
+// ListenConfig.Listen.
 func Listen(network, address string) (Listener, error) {
 	var lc ListenConfig
 	return lc.Listen(context.Background(), network, address)
@@ -728,6 +734,9 @@ func Listen(network, address string) (Listener, error) {
 //
 // See func Dial for a description of the network and address
 // parameters.
+//
+// ListenPacket uses context.Background internally; to specify the context, use
+// ListenConfig.ListenPacket.
 func ListenPacket(network, address string) (PacketConn, error) {
 	var lc ListenConfig
 	return lc.ListenPacket(context.Background(), network, address)
diff --git a/src/net/http/request.go b/src/net/http/request.go
index adba5406e90..5251ebea665 100644
--- a/src/net/http/request.go
+++ b/src/net/http/request.go
@@ -823,7 +823,7 @@ func validMethod(method string) bool {
 	return len(method) > 0 && strings.IndexFunc(method, isNotToken) == -1
 }
 
-// NewRequest wraps NewRequestWithContext using the background context.
+// NewRequest wraps NewRequestWithContext using context.Background.
 func NewRequest(method, url string, body io.Reader) (*Request, error) {
 	return NewRequestWithContext(context.Background(), method, url, body)
 }
diff --git a/src/net/http/socks_bundle.go b/src/net/http/socks_bundle.go
index e4466695899..fc223910398 100644
--- a/src/net/http/socks_bundle.go
+++ b/src/net/http/socks_bundle.go
@@ -362,6 +362,8 @@ func (d *socksDialer) DialWithConn(ctx context.Context, c net.Conn, network, add
 // Unlike DialContext, it returns a raw transport connection instead
 // of a forward proxy connection.
 //
+// Dial uses context.Background internally.
+//
 // Deprecated: Use DialContext or DialWithConn instead.
 func (d *socksDialer) Dial(network, address string) (net.Conn, error) {
 	if err := d.validateTarget(network, address); err != nil {
diff --git a/src/net/lookup.go b/src/net/lookup.go
index 5f7119872a4..03599503bd1 100644
--- a/src/net/lookup.go
+++ b/src/net/lookup.go
@@ -166,6 +166,9 @@ func (r *Resolver) getLookupGroup() *singleflight.Group {
 
 // LookupHost looks up the given host using the local resolver.
 // It returns a slice of that host's addresses.
+//
+// LookupHost uses context.Background internally; to specify the context, use
+// Resolver.LookupHost.
 func LookupHost(host string) (addrs []string, err error) {
 	return DefaultResolver.LookupHost(context.Background(), host)
 }
@@ -353,6 +356,9 @@ func ipAddrsEface(addrs []IPAddr) []interface{} {
 }
 
 // LookupPort looks up the port for the given network and service.
+//
+// LookupPort uses context.Background internally; to specify the context, use
+// Resolver.LookupPort.
 func LookupPort(network, service string) (port int, err error) {
 	return DefaultResolver.LookupPort(context.Background(), network, service)
 }
@@ -389,6 +395,9 @@ func (r *Resolver) LookupPort(ctx context.Context, network, service string) (por
 // LookupCNAME does not return an error if host does not
 // contain DNS "CNAME" records, as long as host resolves to
 // address records.
+//
+// LookupCNAME uses context.Background internally; to specify the context, use
+// Resolver.LookupCNAME.
 func LookupCNAME(host string) (cname string, err error) {
 	return DefaultResolver.lookupCNAME(context.Background(), host)
 }
@@ -434,6 +443,9 @@ func (r *Resolver) LookupSRV(ctx context.Context, service, proto, name string) (
 }
 
 // LookupMX returns the DNS MX records for the given domain name sorted by preference.
+//
+// LookupMX uses context.Background internally; to specify the context, use
+// Resolver.LookupMX.
 func LookupMX(name string) ([]*MX, error) {
 	return DefaultResolver.lookupMX(context.Background(), name)
 }
@@ -444,6 +456,9 @@ func (r *Resolver) LookupMX(ctx context.Context, name string) ([]*MX, error) {
 }
 
 // LookupNS returns the DNS NS records for the given domain name.
+//
+// LookupNS uses context.Background internally; to specify the context, use
+// Resolver.LookupNS.
 func LookupNS(name string) ([]*NS, error) {
 	return DefaultResolver.lookupNS(context.Background(), name)
 }
@@ -454,6 +469,9 @@ func (r *Resolver) LookupNS(ctx context.Context, name string) ([]*NS, error) {
 }
 
 // LookupTXT returns the DNS TXT records for the given domain name.
+//
+// LookupTXT uses context.Background internally; to specify the context, use
+// Resolver.LookupTXT.
 func LookupTXT(name string) ([]string, error) {
 	return DefaultResolver.lookupTXT(context.Background(), name)
 }
@@ -468,6 +486,9 @@ func (r *Resolver) LookupTXT(ctx context.Context, name string) ([]string, error)
 //
 // When using the host C library resolver, at most one result will be
 // returned. To bypass the host resolver, use a custom Resolver.
+//
+// LookupAddr uses context.Background internally; to specify the context, use
+// Resolver.LookupAddr.
 func LookupAddr(addr string) (names []string, err error) {
 	return DefaultResolver.lookupAddr(context.Background(), addr)
 }