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Subject[PATCH] UBI: Fix livelock in produce_free_peb()
Date
The while loop in produce_free_peb() assumes that each work will produce a
free PEB. This is not true.
If ubi->works_count is 1 and the only scheduled work is the
wear_leveling_worker() produce_free_peb() can loop forever in case
nobody schedules an erase work.
Fix this issue by checking in the while loop whether work is scheduled.

Signed-off-by: Richard Weinberger <richard@nod.at>
---
drivers/mtd/ubi/wl.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/mtd/ubi/wl.c b/drivers/mtd/ubi/wl.c
index 0509c8a..6add739 100644
--- a/drivers/mtd/ubi/wl.c
+++ b/drivers/mtd/ubi/wl.c
@@ -272,7 +272,7 @@ static int produce_free_peb(struct ubi_device *ubi)
{
int err;

- while (!ubi->free.rb_node) {
+ while (!ubi->free.rb_node && ubi->works_count) {
spin_unlock(&ubi->wl_lock);

dbg_wl("do one work synchronously");
--
1.8.4.5


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