[PATCH 4.4 087/131] mmc: mmc: fix switch timeout issue caused by jiffies precision

From: Greg Kroah-Hartman
Date: Mon Apr 01 2019 - 13:36:13 EST


4.4-stable review patch. If anyone has any objections, please let me know.

------------------

[ Upstream commit 987aa5f8059613bf85cbb6f64ffbd34f5cb7a9d1 ]

with CONFIG_HZ=100, the precision of jiffies is 10ms, and the
generic_cmd6_time of some card is also 10ms. then, may be current
time is only 5ms, but already timed out caused by jiffies precision.

Signed-off-by: Chaotian Jing <chaotian.jing@xxxxxxxxxxxx>
Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/mmc/core/mmc_ops.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/mmc/core/mmc_ops.c b/drivers/mmc/core/mmc_ops.c
index 1f444269ebbe..76b49b9772d0 100644
--- a/drivers/mmc/core/mmc_ops.c
+++ b/drivers/mmc/core/mmc_ops.c
@@ -542,7 +542,7 @@ int __mmc_switch(struct mmc_card *card, u8 set, u8 index, u8 value,
timeout_ms = MMC_OPS_TIMEOUT_MS;

/* Must check status to be sure of no errors. */
- timeout = jiffies + msecs_to_jiffies(timeout_ms);
+ timeout = jiffies + msecs_to_jiffies(timeout_ms) + 1;
do {
if (send_status) {
err = __mmc_send_status(card, &status, ignore_crc);
--
2.19.1