[FS#800] ath9k sta and ap mode change. system hang

[LEDE Bugs]

The following task has a new comment added:

FS#800 - ath9k sta  and ap mode  change. system hang
User who did this - 李鹏 (lipeng)

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Felix Fietkau  My project  update from OpenWRT 15.05.1 to LEDE 17.01.0 , I get the same result. We can not update again. As I metion  ,I delete some timer  .It worked good . but I do not know why ，So
I  want somebody can expain it
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More information can be found at the following URL:
https://bugs.lede-project.org/index.php?do=details&task_id=800#comment3073