Re: [GIT PULL 6/7] stm class: Fix an endless loop in channel allocation

From: Greg Kroah-Hartman
Date: Thu Feb 21 2019 - 09:44:12 EST


On Thu, Feb 21, 2019 at 03:49:58PM +0200, Alexander Shishkin wrote:
> From: Zhi Jin <zhi.jin@xxxxxxxxx>
>
> There is a bug in the channel allocation logic that leads to an endless
> loop when looking for a contiguous range of channels in a range with a
> mixture of free and occupied channels. For example, opening three
> consequtive channels, closing the first two and requesting 4 channels in
> a row will trigger this soft lockup. The bug is that the search loop
> forgets to skip over the range once it detects that one channel in that
> range is occupied.
>
> Restore the original intent to the logic by fixing the omission.
>
> Fixes: 7bd1d4093c2f ("stm class: Introduce an abstraction for System Trace Module devices")
> Signed-off-by: Zhi Jin <zhi.jin@xxxxxxxxx>
> Signed-off-by: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>

This should have a cc: stable in it, right?

thanks,

greg k-h