[ Upstream commit 7ca8c2c8bbeda2a2a2a9898cd35066bc1dc83836 ]
The module was initializing completions whenever it was going to wait on them, and not when the completion was allocated. This is incorrect according to the completion docs:
Calling init_completion() on the same completion object twice is most likely a bug [...]
Re-initialization is also unnecessary because the module never uses complete_all(). Fix this by only ever initializing the completion a single time, and log if the completions are not consumed as intended (this is not a fatal problem, but should not go unnoticed).
Signed-off-by: George Hilliard thirtythreeforty@gmail.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/staging/mt7621-mmc/sd.c | 18 ++++++++++++++---- 1 file changed, 14 insertions(+), 4 deletions(-)
diff --git a/drivers/staging/mt7621-mmc/sd.c b/drivers/staging/mt7621-mmc/sd.c index 4b26ec896a96f..74f0e57ad2f15 100644 --- a/drivers/staging/mt7621-mmc/sd.c +++ b/drivers/staging/mt7621-mmc/sd.c @@ -468,7 +468,11 @@ static unsigned int msdc_command_start(struct msdc_host *host, host->cmd = cmd; host->cmd_rsp = resp;
- init_completion(&host->cmd_done); + // The completion should have been consumed by the previous command + // response handler, because the mmc requests should be serialized + if (completion_done(&host->cmd_done)) + dev_err(mmc_dev(host->mmc), + "previous command was not handled\n");
sdr_set_bits(host->base + MSDC_INTEN, wints); sdc_send_cmd(rawcmd, cmd->arg); @@ -490,7 +494,6 @@ static unsigned int msdc_command_resp(struct msdc_host *host, MSDC_INT_ACMD19_DONE;
BUG_ON(in_interrupt()); - //init_completion(&host->cmd_done); //sdr_set_bits(host->base + MSDC_INTEN, wints);
spin_unlock(&host->lock); @@ -674,7 +677,13 @@ static int msdc_do_request(struct mmc_host *mmc, struct mmc_request *mrq) //msdc_clr_fifo(host); /* no need */
msdc_dma_on(); /* enable DMA mode first!! */ - init_completion(&host->xfer_done); + + // The completion should have been consumed by the previous + // xfer response handler, because the mmc requests should be + // serialized + if (completion_done(&host->cmd_done)) + dev_err(mmc_dev(host->mmc), + "previous transfer was not handled\n");
/* start the command first*/ if (msdc_command_start(host, cmd, CMD_TIMEOUT) != 0) @@ -693,7 +702,6 @@ static int msdc_do_request(struct mmc_host *mmc, struct mmc_request *mrq) /* for read, the data coming too fast, then CRC error * start DMA no business with CRC. */ - //init_completion(&host->xfer_done); msdc_dma_start(host);
spin_unlock(&host->lock); @@ -1688,6 +1696,8 @@ static int msdc_drv_probe(struct platform_device *pdev) } msdc_init_gpd_bd(host, &host->dma);
+ init_completion(&host->cmd_done); + init_completion(&host->xfer_done); INIT_DELAYED_WORK(&host->card_delaywork, msdc_tasklet_card); spin_lock_init(&host->lock); msdc_init_hw(host);