From 12dfc9e022aa4e8768d127416bf841c169f8c57e Mon Sep 17 00:00:00 2001 From: Mathieu Poirier Date: Thu, 25 Apr 2019 13:52:57 -0600 Subject: [PATCH] coresight: Properly address errors in sink::disable() functions When disabling a sink the reference counter ensures the operation goes through if nobody else is using it. As such if drvdata::mode is already set do CS_MODE_DISABLED, it is an error and should be reported as such. Signed-off-by: Mathieu Poirier Reviewed-by: Suzuki K Poulose Tested-by: Leo Yan Tested-by: Robert Walker Signed-off-by: Greg Kroah-Hartman --- drivers/hwtracing/coresight/coresight-etb10.c | 9 ++++----- drivers/hwtracing/coresight/coresight-tmc-etf.c | 9 ++++----- drivers/hwtracing/coresight/coresight-tmc-etr.c | 9 ++++----- 3 files changed, 12 insertions(+), 15 deletions(-) diff --git a/drivers/hwtracing/coresight/coresight-etb10.c b/drivers/hwtracing/coresight/coresight-etb10.c index 8e63863..6b73bc2e 100644 --- a/drivers/hwtracing/coresight/coresight-etb10.c +++ b/drivers/hwtracing/coresight/coresight-etb10.c @@ -333,11 +333,10 @@ static int etb_disable(struct coresight_device *csdev) return -EBUSY; } - /* Disable the ETB only if it needs to */ - if (drvdata->mode != CS_MODE_DISABLED) { - etb_disable_hw(drvdata); - drvdata->mode = CS_MODE_DISABLED; - } + /* Complain if we (somehow) got out of sync */ + WARN_ON_ONCE(drvdata->mode == CS_MODE_DISABLED); + etb_disable_hw(drvdata); + drvdata->mode = CS_MODE_DISABLED; spin_unlock_irqrestore(&drvdata->spinlock, flags); dev_dbg(drvdata->dev, "ETB disabled\n"); diff --git a/drivers/hwtracing/coresight/coresight-tmc-etf.c b/drivers/hwtracing/coresight/coresight-tmc-etf.c index d50a608..30f8686 100644 --- a/drivers/hwtracing/coresight/coresight-tmc-etf.c +++ b/drivers/hwtracing/coresight/coresight-tmc-etf.c @@ -297,11 +297,10 @@ static int tmc_disable_etf_sink(struct coresight_device *csdev) return -EBUSY; } - /* Disable the TMC only if it needs to */ - if (drvdata->mode != CS_MODE_DISABLED) { - tmc_etb_disable_hw(drvdata); - drvdata->mode = CS_MODE_DISABLED; - } + /* Complain if we (somehow) got out of sync */ + WARN_ON_ONCE(drvdata->mode == CS_MODE_DISABLED); + tmc_etb_disable_hw(drvdata); + drvdata->mode = CS_MODE_DISABLED; spin_unlock_irqrestore(&drvdata->spinlock, flags); diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c index 6a8f39d..9a0b346 100644 --- a/drivers/hwtracing/coresight/coresight-tmc-etr.c +++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c @@ -1417,11 +1417,10 @@ static int tmc_disable_etr_sink(struct coresight_device *csdev) return -EBUSY; } - /* Disable the TMC only if it needs to */ - if (drvdata->mode != CS_MODE_DISABLED) { - tmc_etr_disable_hw(drvdata); - drvdata->mode = CS_MODE_DISABLED; - } + /* Complain if we (somehow) got out of sync */ + WARN_ON_ONCE(drvdata->mode == CS_MODE_DISABLED); + tmc_etr_disable_hw(drvdata); + drvdata->mode = CS_MODE_DISABLED; spin_unlock_irqrestore(&drvdata->spinlock, flags); -- 2.7.4