diff --git a/repos/os/src/drivers/ahci/ata_protocol.h b/repos/os/src/drivers/ahci/ata_protocol.h
index adecb5537..e37098b68 100644
--- a/repos/os/src/drivers/ahci/ata_protocol.h
+++ b/repos/os/src/drivers/ahci/ata_protocol.h
@@ -124,6 +124,8 @@ class Ata::Protocol : public Ahci::Protocol, Noncopyable
 {
 	private:
 
+		bool _syncing { false };
+
 		struct Request : Block::Request
 		{
 			bool valid() const { return operation.valid(); }
@@ -162,6 +164,9 @@ class Ata::Protocol : public Ahci::Protocol, Noncopyable
 			block_number_t end = block_number + request.operation.count - 1;
 
 			auto overlap_check = [&] (Request const &req) {
+				if (req.operation.type == Block::Operation::Type::SYNC)
+					return false;
+
 				block_number_t pending_start = req.operation.block_number;
 				block_number_t pending_end   = pending_start + req.operation.count - 1;
 
@@ -266,6 +271,8 @@ class Ata::Protocol : public Ahci::Protocol, Noncopyable
 
 			_slot_states = port.read<Port::Ci>() | port.read<Port::Sact>();
 			port.stop();
+
+			_syncing = false;
 		}
 
 		Block::Session::Info info() const override
@@ -280,10 +287,18 @@ class Ata::Protocol : public Ahci::Protocol, Noncopyable
 
 		Response submit(Port &port, Block::Request const request) override
 		{
-			if (_writeable == false && request.operation.type == Block::Operation::Type::WRITE)
+			Block::Operation const op = request.operation;
+
+			bool const sync  = (op.type == Block::Operation::Type::SYNC);
+			bool const write = (op.type == Block::Operation::Type::WRITE);
+
+			if ((sync && _slot_states) || _syncing)
+				return Response::RETRY;
+
+			if (_writeable == false && write)
 				return Response::REJECTED;
 
-			if (Block::Operation::has_payload(request.operation.type)) {
+			if (Block::Operation::has_payload(op.type)) {
 				if (port.sanity_check(request) == false || port.dma_base == 0)
 					return Response::REJECTED;
 
@@ -298,7 +313,6 @@ class Ata::Protocol : public Ahci::Protocol, Noncopyable
 
 			*r = request;
 
-			Block::Operation op = request.operation;
 			size_t slot         = _slots.index(*r);
 			_slot_states       |= 1u << slot;
 
@@ -308,13 +322,9 @@ class Ata::Protocol : public Ahci::Protocol, Noncopyable
 			                    op.count * _block_size());
 
 			/* setup ATA command */
-
-			/* write bit for command header + read/write ATA requests */
-			bool const write = (op.type == Block::Operation::Type::WRITE);
-			bool const sync  = (op.type == Block::Operation::Type::SYNC);
-
 			if (sync) {
 				table.fis.flush_cache_ext();
+				_syncing = true;
 			} else if (_ncq_support(port)) {
 				table.fis.fpdma(write == false, op.block_number, op.count, slot);
 				/* ensure that 'Cmd::St' is 1 before writing 'Sact' */