[FS#112] Kernel: SysRq spams on boot since kernel 4.4.19

[LEDE Bugs]

The following task has a new comment added:

FS#112 - Kernel: SysRq spams on boot since kernel 4.4.19
User who did this - Koen Vandeputte (xback)

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Hi Felix,

I tested your patch and it works fine.

Tests conducted:
- Enable Serial SysRQ, attach the modem,  reboot 10 times. --> sysrq pops up on a regular base
- Disable Serial SysRQ, attach the modem,  reboot 10 times. --> spam is gone

Would it be possible to also provide a child subflag in the normal menuconfig (Parent = KERNEL_MAGIC_SYSRQ) ?
This would avoid having to run a seperate kernel_menuconfig to disable serial sysrq when using "make oldconfig" on new builds


Thanks for your support!

Koen
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More information can be found at the following URL:
https://bugs.lede-project.org/index.php?do=details&task_id=112#comment325