tpm_ibmvtpm_send() can fail during PowerVM Live Partition Mobility resume with an H_CLOSED return from ibmvtpm_send_crq(). The PAPR says, 'The "partner partition suspended" transport event disables the associated CRQ such that any H_SEND_CRQ hcall() to the associated CRQ returns H_Closed until the CRQ has been explicitly enabled using the H_ENABLE_CRQ hcall.' This patch adds a check in tpm_ibmvtpm_send() for an H_CLOSED return from ibmvtpm_send_crq() and in that case calls tpm_ibmvtpm_resume() and retries the ibmvtpm_send_crq() once.

Reported-by: Linh Pham phaml@us.ibm.com Reviewed-by: Stefan Berger stefanb@linux.ibm.com Signed-off-by: George Wilson gcwilson@linux.ibm.com Tested-by: Linh Pham phaml@us.ibm.com Fixes: 132f76294744 ("drivers/char/tpm: Add new device driver to support IBM vTPM") Cc: stable@vger.kernel.org --- drivers/char/tpm/tpm_ibmvtpm.c | 136 ++++++++++++++++++--------------- 1 file changed, 73 insertions(+), 63 deletions(-)

diff --git a/drivers/char/tpm/tpm_ibmvtpm.c b/drivers/char/tpm/tpm_ibmvtpm.c index 78cc52690177..e82013d587b4 100644 --- a/drivers/char/tpm/tpm_ibmvtpm.c +++ b/drivers/char/tpm/tpm_ibmvtpm.c @@ -1,6 +1,6 @@ // SPDX-License-Identifier: GPL-2.0-only /* - * Copyright (C) 2012 IBM Corporation + * Copyright (C) 2012-2020 IBM Corporation * * Author: Ashley Lai ashleydlai@gmail.com * @@ -133,6 +133,64 @@ static int tpm_ibmvtpm_recv(struct tpm_chip *chip, u8 *buf, size_t count) return len; }

+/** + * ibmvtpm_crq_send_init - Send a CRQ initialize message + * @ibmvtpm: vtpm device struct + * + * Return: + * 0 on success. + * Non-zero on failure. + */ +static int ibmvtpm_crq_send_init(struct ibmvtpm_dev *ibmvtpm) +{ + int rc; + + rc = ibmvtpm_send_crq_word(ibmvtpm->vdev, INIT_CRQ_CMD); + if (rc != H_SUCCESS) + dev_err(ibmvtpm->dev, + "%s failed rc=%d\n", __func__, rc); + + return rc; +} + +/** + * tpm_ibmvtpm_resume - Resume from suspend + * + * @dev: device struct + * + * Return: Always 0. + */ +static int tpm_ibmvtpm_resume(struct device *dev) +{ + struct tpm_chip *chip = dev_get_drvdata(dev); + struct ibmvtpm_dev *ibmvtpm = dev_get_drvdata(&chip->dev); + int rc = 0; + + do { + if (rc) + msleep(100); + rc = plpar_hcall_norets(H_ENABLE_CRQ, + ibmvtpm->vdev->unit_address); + } while (rc == H_IN_PROGRESS || rc == H_BUSY || H_IS_LONG_BUSY(rc)); + + if (rc) { + dev_err(dev, "Error enabling ibmvtpm rc=%d\n", rc); + return rc; + } + + rc = vio_enable_interrupts(ibmvtpm->vdev); + if (rc) { + dev_err(dev, "Error vio_enable_interrupts rc=%d\n", rc); + return rc; + } + + rc = ibmvtpm_crq_send_init(ibmvtpm); + if (rc) + dev_err(dev, "Error send_init rc=%d\n", rc); + + return rc; +} + /** * tpm_ibmvtpm_send() - Send a TPM command * @chip: tpm chip struct @@ -146,6 +204,7 @@ static int tpm_ibmvtpm_recv(struct tpm_chip *chip, u8 *buf, size_t count) static int tpm_ibmvtpm_send(struct tpm_chip *chip, u8 *buf, size_t count) { struct ibmvtpm_dev *ibmvtpm = dev_get_drvdata(&chip->dev); + bool retry = true; int rc, sig;

if (!ibmvtpm->rtce_buf) { @@ -179,18 +238,27 @@ static int tpm_ibmvtpm_send(struct tpm_chip *chip, u8 *buf, size_t count) */ ibmvtpm->tpm_processing_cmd = true;

+again: rc = ibmvtpm_send_crq(ibmvtpm->vdev, IBMVTPM_VALID_CMD, VTPM_TPM_COMMAND, count, ibmvtpm->rtce_dma_handle); if (rc != H_SUCCESS) { + /* + * H_CLOSED can be returned after LPM resume. Call + * tpm_ibmvtpm_resume() to re-enable the CRQ then retry + * ibmvtpm_send_crq() once before failing. + */ + if (rc == H_CLOSED && retry) { + tpm_ibmvtpm_resume(ibmvtpm->dev); + retry = false; + goto again; + } dev_err(ibmvtpm->dev, "tpm_ibmvtpm_send failed rc=%d\n", rc); - rc = 0; ibmvtpm->tpm_processing_cmd = false; - } else - rc = 0; + }

spin_unlock(&ibmvtpm->rtce_lock); - return rc; + return 0; }

static void tpm_ibmvtpm_cancel(struct tpm_chip *chip) @@ -268,26 +336,6 @@ static int ibmvtpm_crq_send_init_complete(struct ibmvtpm_dev *ibmvtpm) return rc; }

-/** - * ibmvtpm_crq_send_init - Send a CRQ initialize message - * @ibmvtpm: vtpm device struct - * - * Return: - * 0 on success. - * Non-zero on failure. - */ -static int ibmvtpm_crq_send_init(struct ibmvtpm_dev *ibmvtpm) -{ - int rc; - - rc = ibmvtpm_send_crq_word(ibmvtpm->vdev, INIT_CRQ_CMD); - if (rc != H_SUCCESS) - dev_err(ibmvtpm->dev, - "ibmvtpm_crq_send_init failed rc=%d\n", rc); - - return rc; -} - /** * tpm_ibmvtpm_remove - ibm vtpm remove entry point * @vdev: vio device struct @@ -400,44 +448,6 @@ static int ibmvtpm_reset_crq(struct ibmvtpm_dev *ibmvtpm) ibmvtpm->crq_dma_handle, CRQ_RES_BUF_SIZE); }

-/** - * tpm_ibmvtpm_resume - Resume from suspend - * - * @dev: device struct - * - * Return: Always 0. - */ -static int tpm_ibmvtpm_resume(struct device *dev) -{ - struct tpm_chip *chip = dev_get_drvdata(dev); - struct ibmvtpm_dev *ibmvtpm = dev_get_drvdata(&chip->dev); - int rc = 0; - - do { - if (rc) - msleep(100); - rc = plpar_hcall_norets(H_ENABLE_CRQ, - ibmvtpm->vdev->unit_address); - } while (rc == H_IN_PROGRESS || rc == H_BUSY || H_IS_LONG_BUSY(rc)); - - if (rc) { - dev_err(dev, "Error enabling ibmvtpm rc=%d\n", rc); - return rc; - } - - rc = vio_enable_interrupts(ibmvtpm->vdev); - if (rc) { - dev_err(dev, "Error vio_enable_interrupts rc=%d\n", rc); - return rc; - } - - rc = ibmvtpm_crq_send_init(ibmvtpm); - if (rc) - dev_err(dev, "Error send_init rc=%d\n", rc); - - return rc; -} - static bool tpm_ibmvtpm_req_canceled(struct tpm_chip *chip, u8 status) { return (status == 0);