The calcuation for limit of reserved token did not take into account the change the user wanted vs the current group reserved token. This causes changing of the reserved token to be possible only after we set the value of the reserved token back to 0. Fix calculation so we can set a value that is non zero for reserved token. Fixes: c52ca478233c ("dmaengine: idxd: add configuration component of driver") Reported-by: Jerry Chen <jerry.t.chen@xxxxxxxxx> Signed-off-by: Dave Jiang <dave.jiang@xxxxxxxxx> --- drivers/dma/idxd/sysfs.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/dma/idxd/sysfs.c b/drivers/dma/idxd/sysfs.c index 298855ca934f..edbfe83325eb 100644 --- a/drivers/dma/idxd/sysfs.c +++ b/drivers/dma/idxd/sysfs.c @@ -519,7 +519,7 @@ static ssize_t group_tokens_reserved_store(struct device *dev, if (val > idxd->max_tokens) return -EINVAL; - if (val > idxd->nr_tokens) + if (val > idxd->nr_tokens + group->tokens_reserved) return -EINVAL; group->tokens_reserved = val;