From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pj1-f70.google.com (mail-pj1-f70.google.com [209.85.216.70]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 57B6E38E5DC for ; Thu, 27 Aug 2026 18:05:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.216.70 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787853914; cv=none; b=hRFTKzjeVSK36Cr9N7bKylngRE4ywlIadnWiXHTpqo5fgREXbLs1X26/K3affS2QZQmj2lxm30cUvvFfb17mzzzo3Gza69z+5d5584gJx3GXNBvAE0LfQWQivcpX0JHhD8W59f8v3Tfs1hntFVaX91w7l4wYnwka/RLuNPHwJSU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787853914; c=relaxed/simple; bh=MnzqmFryyqKnWLjnUS6aWjVVD6eJJFB1huY4ZJIHQnU=; h=Date:Mime-Version:Message-ID:Subject:From:To:Cc:Content-Type; b=hoUdoeC1tiYL622wzT7nfy3xywpvFfUon3NdYVxkEGJ8fkJU3dEcwzzHO0PIhcYb9RaWRxN7WAQVC+w6TXveench0BJJyPsHtQoA3YMHt0ZRvTMsQAwtZuOcpe5Bf1SIWTFEVeRNgI5dICXtvhnmjXeFlpLN+9nwh5kIqO+VEv4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--robbarnes.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=fxHQmbGd; arc=none smtp.client-ip=209.85.216.70 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--robbarnes.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="fxHQmbGd" Received: by mail-pj1-f70.google.com with SMTP id 98e67ed59e1d1-38e54b6556aso325859a91.2 for ; Thu, 27 Aug 2026 11:05:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1787853913; x=1788458713; darn=vger.kernel.org; h=content-type:cc:to:from:subject:message-id:mime-version:date:from :to:cc:subject:date:message-id:reply-to:content-type; bh=W0xVuyq4wjYUJdSC5HORoIWzL+nU0+uyo3jftFJ3RjY=; b=fxHQmbGdbODTHNeWvGrNiNHs01FehkTINMmhmIgPLXMeMDsGHlwbwkOQYwp0wmF/uK 9HDcDHsPtkP23J6w0WSerzLrtSrQx1FghBknjLzYJDQmyldvvHYx6oQvrGKFHP/3atBw EMwAYkcJDpC6PJytQOrBRx8Zwh8qUglsA1dh+lIQ16ZWdahrzTJGHdLbareT2g/jfRAj YWJqwni/6LyyyO8y9PchDTFqwIfq7mCCU54Fz+BMWptDIWKLNBmciL7jMJ+4fNUItqqf rQGIU3pm7l5JSoQb4NkXcpVEPCss4yhGmSkkB0QMcucFz1n2DLDCQgmbq2ZaHFRtuiKY 1oBw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1787853913; x=1788458713; h=content-type:cc:to:from:subject:message-id:mime-version:date :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to :content-type; bh=W0xVuyq4wjYUJdSC5HORoIWzL+nU0+uyo3jftFJ3RjY=; b=kZ8IMw0bQnC56LmAU1R/SEJX4/TmYhXSv0QvhvyRs159BIIwAOK3qGPKrZXGmN3+yC 2tXdxBk/im1hZ597b57WTg5Mpjoe+FZXKA/WuW62wxGCu1mv9KWH0N5BFS4QE/4wZ92X MZLnamHb2lxt1+wohiD5mgJzg0YF/V1Ug5HBpFgYvexig15C2hSA5nyjAbAeuROAn/mp FoG6XxZcufy/+keUsdpUIpFqV0IsSclzz9HdqAYBsp9Eg2oTyY+dHkvtRsbLk4VhhdT2 NRdef51ASlTA7xID8/P+mdv0IeJGF2rm9bLaHjeyIBQeFj/qJ4Rx010S3X22Fn9bkPRT 4vrA== X-Forwarded-Encrypted: i=1; AHgh+RoZNNdWeBTg6q2x4edonVxR+Io63iKsXM5E9HeFNpeqBeTLib0aGdDqOtSdcp+KnoD1Iwg7PxzGqwZm90k=@vger.kernel.org X-Gm-Message-State: AFuF++kABY9SxYlQ6dPHk7X4e0u7K+BiRERj8Xhv9QBpXzjF7cTfpkbY tzRz/xghC5OpfXXLBqJPtTT1F25KFibWndVsHco/gYUXQxFFS1c+ixdApy+xalJ388lQidFLiVM qEDVuPWrmUqMtFu60JQ== X-Received: from dlbqy10.prod.google.com ([2002:a05:7022:ef0a:b0:141:b6d:b7af]) (user=robbarnes job=prod-delivery.src-stubby-dispatcher) by 2002:a17:90b:2f0f:b0:380:540:d499 with SMTP id 98e67ed59e1d1-396d0ed0023mr2127530a91.6.1787853911845; Thu, 27 Aug 2026 11:05:11 -0700 (PDT) Date: Thu, 27 Aug 2026 12:05:11 -0600 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 X-Mailer: git-send-email 2.55.0.897.gb25b4bd76c-goog Message-ID: <20260827180511.2825660-1-robbarnes@google.com> Subject: [PATCH v4] platform/chrome: cros_ec_proto: Fix deferred response From: Rob Barnes To: bleung@chromium.org, tzungbi@kernel.org Cc: tomhughes@chromium.org, chrome-platform@lists.linux.dev, linux-kernel@vger.kernel.org, Rob Barnes Content-Type: text/plain; charset="UTF-8" When cros_ec_wait_until_complete() succeeds after an EC_RES_IN_PROGRESS status, it previously returned the 4-byte transfer size of EC_CMD_GET_COMMS_STATUS. For 0-byte payload commands (such as EC_CMD_FLASH_ERASE), userspace received 4 bytes instead of 0, causing response size validation errors. For commands expecting non-zero response payloads, the kernel exited without issuing EC_CMD_RESEND_RESPONSE, leaving response buffers uninitialized. Refactor cros_ec_wait_until_complete() to pass orig_msg, issue EC_CMD_RESEND_RESPONSE into orig_msg->data when insize > 0, and return 0 for 0-byte response commands. Signed-off-by: Rob Barnes --- v4: - Rebase against upstream chrome-platform/for-next branch (Tzung-Bi). - Send patch using git-send-email via Google Mail Relay to prevent MTA line-wrapping (Tzung-Bi). v3: - Rebase against upstream chrome-platform tree (Tzung-Bi). v2: - Drop redundant commit description sentences (Tzung-Bi). - Align function signature parameters to open parenthesis (Tzung-Bi). - Check orig_msg->insize == 0 and add comments explaining the logic (Tzung-Bi / Rob). - Use u32 instead of uint32_t (Tzung-Bi). - Rename 0bytes test to 0byte (Tzung-Bi). - Check header immutability for insize in test cases (Tzung-Bi). --- drivers/platform/chrome/cros_ec_proto.c | 32 +++- drivers/platform/chrome/cros_ec_proto_test.c | 158 ++++++++++++++++++- 2 files changed, 183 insertions(+), 7 deletions(-) diff --git a/drivers/platform/chrome/cros_ec_proto.c b/drivers/platform/chrome/cros_ec_proto.c index 1d8d9168ec1a..6d7c57e381e5 100644 --- a/drivers/platform/chrome/cros_ec_proto.c +++ b/drivers/platform/chrome/cros_ec_proto.c @@ -138,7 +138,8 @@ static int cros_ec_xfer_command(struct cros_ec_device *ec_dev, struct cros_ec_co return ret; } -static int cros_ec_wait_until_complete(struct cros_ec_device *ec_dev, uint32_t *result) +static int cros_ec_wait_until_complete(struct cros_ec_device *ec_dev, + struct cros_ec_command *orig_msg) { DEFINE_RAW_FLEX(struct cros_ec_command, msg, data, sizeof(struct ec_response_get_comms_status)); @@ -161,7 +162,7 @@ static int cros_ec_wait_until_complete(struct cros_ec_device *ec_dev, uint32_t * if (ret < 0) return ret; - *result = msg->result; + orig_msg->result = msg->result; if (msg->result != EC_RES_SUCCESS) return ret; @@ -170,8 +171,31 @@ static int cros_ec_wait_until_complete(struct cros_ec_device *ec_dev, uint32_t * break; } - if (!(status->flags & EC_COMMS_STATUS_PROCESSING)) + if (!(status->flags & EC_COMMS_STATUS_PROCESSING)) { + u32 orig_cmd, orig_outsize, orig_version; + + /* If no response payload is expected, return 0. */ + if (orig_msg->insize == 0) + return 0; + + /* + * Request the response using EC_CMD_RESEND_RESPONSE. + * Restore the original message fields so it appears + * to be a direct response to the original command. + */ + orig_cmd = orig_msg->command; + orig_outsize = orig_msg->outsize; + orig_version = orig_msg->version; + + orig_msg->command = EC_CMD_RESEND_RESPONSE; + orig_msg->outsize = 0; + orig_msg->version = 0; + ret = cros_ec_xfer_command(ec_dev, orig_msg); + orig_msg->command = orig_cmd; + orig_msg->outsize = orig_outsize; + orig_msg->version = orig_version; return ret; + } } if (i >= EC_COMMAND_RETRIES) @@ -185,7 +209,7 @@ static int cros_ec_send_command(struct cros_ec_device *ec_dev, struct cros_ec_co int ret = cros_ec_xfer_command(ec_dev, msg); if (msg->result == EC_RES_IN_PROGRESS) - ret = cros_ec_wait_until_complete(ec_dev, &msg->result); + ret = cros_ec_wait_until_complete(ec_dev, msg); return ret; } diff --git a/drivers/platform/chrome/cros_ec_proto_test.c b/drivers/platform/chrome/cros_ec_proto_test.c index 3f281996a686..a7b1d64f78ce 100644 --- a/drivers/platform/chrome/cros_ec_proto_test.c +++ b/drivers/platform/chrome/cros_ec_proto_test.c @@ -1744,7 +1744,7 @@ static void cros_ec_proto_test_cmd_xfer_protocol_v2_no_op(struct kunit *test) KUNIT_EXPECT_EQ(test, ret, -EIO); } -static void cros_ec_proto_test_cmd_xfer_in_progress_normal(struct kunit *test) +static void cros_ec_proto_test_cmd_xfer_in_progress_payload_0byte(struct kunit *test) { struct cros_ec_proto_test_priv *priv = test->priv; struct cros_ec_device *ec_dev = &priv->ec_dev; @@ -1774,7 +1774,7 @@ static void cros_ec_proto_test_cmd_xfer_in_progress_normal(struct kunit *test) } ret = cros_ec_cmd_xfer(ec_dev, &msg); - KUNIT_EXPECT_EQ(test, ret, sizeof(struct ec_response_get_comms_status)); + KUNIT_EXPECT_EQ(test, ret, 0); KUNIT_EXPECT_EQ(test, msg.result, EC_RES_SUCCESS); @@ -1799,6 +1799,156 @@ static void cros_ec_proto_test_cmd_xfer_in_progress_normal(struct kunit *test) KUNIT_EXPECT_EQ(test, cros_kunit_ec_pkt_xfer_mock_called, 2); } +static void cros_ec_proto_test_cmd_xfer_in_progress_payload_4bytes(struct kunit *test) +{ + struct cros_ec_proto_test_priv *priv = test->priv; + struct cros_ec_device *ec_dev = &priv->ec_dev; + struct ec_xfer_mock *mock; + u8 resp_data[4] = {0x11, 0x22, 0x33, 0x44}; + struct { + struct cros_ec_command msg; + u8 data[4]; + } buf; + struct cros_ec_command *msg = &buf.msg; + int ret; + + memset(&buf, 0, sizeof(buf)); + msg->version = 1; + msg->command = 0x1234; + msg->outsize = 2; + msg->insize = sizeof(buf.data); + + ec_dev->pkt_xfer = cros_kunit_ec_pkt_xfer_mock; + + /* For initial command returning EC_RES_IN_PROGRESS. */ + { + mock = cros_kunit_ec_xfer_mock_addx(test, 0, EC_RES_IN_PROGRESS, 0); + KUNIT_ASSERT_PTR_NE(test, mock, NULL); + } + + /* For EC_CMD_GET_COMMS_STATUS status polling. */ + { + struct ec_response_get_comms_status *data; + + mock = cros_kunit_ec_xfer_mock_add(test, sizeof(*data)); + KUNIT_ASSERT_PTR_NE(test, mock, NULL); + + data = (struct ec_response_get_comms_status *)mock->o_data; + data->flags = 0; + } + + /* For EC_CMD_RESEND_RESPONSE returning 4 bytes payload. */ + { + mock = cros_kunit_ec_xfer_mock_add(test, sizeof(resp_data)); + KUNIT_ASSERT_PTR_NE(test, mock, NULL); + memcpy(mock->o_data, resp_data, sizeof(resp_data)); + } + + ret = cros_ec_cmd_xfer(ec_dev, msg); + KUNIT_EXPECT_EQ(test, ret, 4); + KUNIT_EXPECT_EQ(test, msg->result, EC_RES_SUCCESS); + KUNIT_EXPECT_EQ(test, msg->command, 0x1234); + KUNIT_EXPECT_EQ(test, msg->outsize, 2); + KUNIT_EXPECT_EQ(test, msg->insize, sizeof(buf.data)); + KUNIT_EXPECT_EQ(test, msg->version, 1); + KUNIT_EXPECT_EQ(test, memcmp(msg->data, resp_data, sizeof(resp_data)), 0); + + /* Verify mock sequence */ + { + mock = cros_kunit_ec_xfer_mock_next(); + KUNIT_EXPECT_PTR_NE(test, mock, NULL); + + mock = cros_kunit_ec_xfer_mock_next(); + KUNIT_EXPECT_PTR_NE(test, mock, NULL); + KUNIT_EXPECT_EQ(test, mock->msg.command, EC_CMD_GET_COMMS_STATUS); + + mock = cros_kunit_ec_xfer_mock_next(); + KUNIT_EXPECT_PTR_NE(test, mock, NULL); + KUNIT_EXPECT_EQ(test, mock->msg.command, EC_CMD_RESEND_RESPONSE); + KUNIT_EXPECT_EQ(test, mock->msg.outsize, 0); + KUNIT_EXPECT_EQ(test, mock->msg.version, 0); + KUNIT_EXPECT_EQ(test, mock->msg.insize, 4); + } + + KUNIT_EXPECT_EQ(test, cros_kunit_ec_pkt_xfer_mock_called, 3); +} + +static void cros_ec_proto_test_cmd_xfer_in_progress_payload_gt4bytes(struct kunit *test) +{ + struct cros_ec_proto_test_priv *priv = test->priv; + struct cros_ec_device *ec_dev = &priv->ec_dev; + struct ec_xfer_mock *mock; + u8 resp_data[16]; + struct { + struct cros_ec_command msg; + u8 data[16]; + } buf; + struct cros_ec_command *msg = &buf.msg; + int ret, i; + + for (i = 0; i < sizeof(resp_data); ++i) + resp_data[i] = (u8)(i + 1); + + memset(&buf, 0, sizeof(buf)); + msg->version = 0; + msg->command = 0x5678; + msg->insize = sizeof(buf.data); + + ec_dev->pkt_xfer = cros_kunit_ec_pkt_xfer_mock; + + /* For initial command returning EC_RES_IN_PROGRESS. */ + { + mock = cros_kunit_ec_xfer_mock_addx(test, 0, EC_RES_IN_PROGRESS, 0); + KUNIT_ASSERT_PTR_NE(test, mock, NULL); + } + + /* For EC_CMD_GET_COMMS_STATUS status polling. */ + { + struct ec_response_get_comms_status *data; + + mock = cros_kunit_ec_xfer_mock_add(test, sizeof(*data)); + KUNIT_ASSERT_PTR_NE(test, mock, NULL); + + data = (struct ec_response_get_comms_status *)mock->o_data; + data->flags = 0; + } + + /* For EC_CMD_RESEND_RESPONSE returning 16 bytes payload. */ + { + mock = cros_kunit_ec_xfer_mock_add(test, sizeof(resp_data)); + KUNIT_ASSERT_PTR_NE(test, mock, NULL); + memcpy(mock->o_data, resp_data, sizeof(resp_data)); + } + + ret = cros_ec_cmd_xfer(ec_dev, msg); + KUNIT_EXPECT_EQ(test, ret, 16); + KUNIT_EXPECT_EQ(test, msg->result, EC_RES_SUCCESS); + KUNIT_EXPECT_EQ(test, msg->command, 0x5678); + KUNIT_EXPECT_EQ(test, msg->outsize, 0); + KUNIT_EXPECT_EQ(test, msg->insize, sizeof(buf.data)); + KUNIT_EXPECT_EQ(test, msg->version, 0); + KUNIT_EXPECT_EQ(test, memcmp(msg->data, resp_data, sizeof(resp_data)), 0); + + /* Verify mock sequence */ + { + mock = cros_kunit_ec_xfer_mock_next(); + KUNIT_EXPECT_PTR_NE(test, mock, NULL); + + mock = cros_kunit_ec_xfer_mock_next(); + KUNIT_EXPECT_PTR_NE(test, mock, NULL); + KUNIT_EXPECT_EQ(test, mock->msg.command, EC_CMD_GET_COMMS_STATUS); + + mock = cros_kunit_ec_xfer_mock_next(); + KUNIT_EXPECT_PTR_NE(test, mock, NULL); + KUNIT_EXPECT_EQ(test, mock->msg.command, EC_CMD_RESEND_RESPONSE); + KUNIT_EXPECT_EQ(test, mock->msg.outsize, 0); + KUNIT_EXPECT_EQ(test, mock->msg.version, 0); + KUNIT_EXPECT_EQ(test, mock->msg.insize, 16); + } + + KUNIT_EXPECT_EQ(test, cros_kunit_ec_pkt_xfer_mock_called, 3); +} + static void cros_ec_proto_test_cmd_xfer_in_progress_retries_eagain(struct kunit *test) { struct cros_ec_proto_test_priv *priv = test->priv; @@ -2703,7 +2853,9 @@ static struct kunit_case cros_ec_proto_test_cases[] = { KUNIT_CASE(cros_ec_proto_test_cmd_xfer_protocol_v3_no_op), KUNIT_CASE(cros_ec_proto_test_cmd_xfer_protocol_v2_normal), KUNIT_CASE(cros_ec_proto_test_cmd_xfer_protocol_v2_no_op), - KUNIT_CASE(cros_ec_proto_test_cmd_xfer_in_progress_normal), + KUNIT_CASE(cros_ec_proto_test_cmd_xfer_in_progress_payload_0byte), + KUNIT_CASE(cros_ec_proto_test_cmd_xfer_in_progress_payload_4bytes), + KUNIT_CASE(cros_ec_proto_test_cmd_xfer_in_progress_payload_gt4bytes), KUNIT_CASE(cros_ec_proto_test_cmd_xfer_in_progress_retries_eagain), KUNIT_CASE(cros_ec_proto_test_cmd_xfer_in_progress_retries_status_processing), KUNIT_CASE(cros_ec_proto_test_cmd_xfer_in_progress_xfer_error), -- 2.55.0.897.gb25b4bd76c-goog