diff options
| author | Stefan Berger <stefanb@linux.ibm.com> | 2020-03-12 18:53:31 +0300 |
|---|---|---|
| committer | Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> | 2020-03-15 21:12:52 +0300 |
| commit | d8d74ea3c00214aee1e1826ca18e77944812b9b4 (patch) | |
| tree | 9bc7320e48f530bba9f6311f049e8b4c4619b51d /drivers/char/tpm/tpm_ibmvtpm.c | |
| parent | 5cb2ace90deb6df9c90172f904fb4a12ee4d443a (diff) | |
| download | linux-d8d74ea3c00214aee1e1826ca18e77944812b9b4.tar.xz | |
tpm: ibmvtpm: Wait for buffer to be set before proceeding
Synchronize with the results from the CRQs before continuing with
the initialization. This avoids trying to send TPM commands while
the rtce buffer has not been allocated, yet.
This patch fixes an existing race condition that may occurr if the
hypervisor does not quickly respond to the VTPM_GET_RTCE_BUFFER_SIZE
request sent during initialization and therefore the ibmvtpm->rtce_buf
has not been allocated at the time the first TPM command is sent.
Fixes: 132f76294744 ("drivers/char/tpm: Add new device driver to support IBM vTPM")
Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
Acked-by: Nayna Jain <nayna@linux.ibm.com>
Tested-by: Nayna Jain <nayna@linux.ibm.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Diffstat (limited to 'drivers/char/tpm/tpm_ibmvtpm.c')
| -rw-r--r-- | drivers/char/tpm/tpm_ibmvtpm.c | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/drivers/char/tpm/tpm_ibmvtpm.c b/drivers/char/tpm/tpm_ibmvtpm.c index 78cc52690177..cfe40e7b1ba4 100644 --- a/drivers/char/tpm/tpm_ibmvtpm.c +++ b/drivers/char/tpm/tpm_ibmvtpm.c @@ -571,6 +571,7 @@ static irqreturn_t ibmvtpm_interrupt(int irq, void *vtpm_instance) */ while ((crq = ibmvtpm_crq_get_next(ibmvtpm)) != NULL) { ibmvtpm_crq_process(crq, ibmvtpm); + wake_up_interruptible(&ibmvtpm->crq_queue.wq); crq->valid = 0; smp_wmb(); } @@ -618,6 +619,7 @@ static int tpm_ibmvtpm_probe(struct vio_dev *vio_dev, } crq_q->num_entry = CRQ_RES_BUF_SIZE / sizeof(*crq_q->crq_addr); + init_waitqueue_head(&crq_q->wq); ibmvtpm->crq_dma_handle = dma_map_single(dev, crq_q->crq_addr, CRQ_RES_BUF_SIZE, DMA_BIDIRECTIONAL); @@ -670,6 +672,13 @@ static int tpm_ibmvtpm_probe(struct vio_dev *vio_dev, if (rc) goto init_irq_cleanup; + if (!wait_event_timeout(ibmvtpm->crq_queue.wq, + ibmvtpm->rtce_buf != NULL, + HZ)) { + dev_err(dev, "CRQ response timed out\n"); + goto init_irq_cleanup; + } + return tpm_chip_register(chip); init_irq_cleanup: do { |