Re: [PATCH v4 1/2] tty: sysrq: don't expose a partially written reset_seq
From: Greg KH
Date: Fri Oct 30 2026 - 07:53:25 EST
On Fri, Oct 30, 2026 at 07:33:56PM +0800, Zhan Xusheng wrote:
> Hi Greg,
>
> On Fri, Oct 30, 2026 at 09:33:41AM +0100, Greg KH wrote:
> > So this feature has never worked? Or it is just "one change only"? So
> > your change is an addition to the feature, not a bugfix?
>
> It is a fix. 154b7a489a5b ("Input: sysrq - allow specifying alternate
> reset sequence") added reset_seq as a writable parameter, together with
> a version counter so that each keyboard rereads the sequence after a
> write. The reread just never clears the old keys, so on a keyboard
> that already used the old value, a new one has never worked. Hardly
> anyone changes it at runtime, which is likely why nobody noticed.
>
> > So this isn't a "real" issue? If you are modifying the key sequence,
> > how can you press the key at the same time? Doing "major" rework for
> > that might just not be worth it.
>
> Agreed, please drop 1/2. With only 2/2, that race can hit any
> keyboard, not only ones that never used a sequence. Do you want 2/2
> resent on its own?
Please resend whatever you feel should actually be applied, with better
changelog text explaining all of this.
thanks,
greg k-h