Re: [PATCH] Revert "interconnect: qcom: x1e80100: enable QoS configuration"

[Marc Zyngier <maz@kernel.org>]

On Mon, 21 Sep 2026 22:36:36 +0100,
Georgi Djakov <djakov@kernel.org> wrote:
> 
> On 9/21/26 11:47 PM, Marc Zyngier wrote:
> > On Tue, 15 Sep 2026 13:37:03 +0100,
> > Marc Zyngier <maz@kernel.org> wrote:
> >> 
> >> This reverts commit 5a8b2cc36e796d595c9d97eab23c2be22805cc1c.
> >> 
> >> Since the introduction of this QoS change, X1 machines based on the
> >> Purwa SoC (such as the Lenovo Mini X) take a hard reset at boot time.
> >> 
> >> Other machines based on Hamoa (such as the X1E001DE Snapdragon Devkit)
> >> end-up with a similar hard reset while under load, most likely due to
> >> the PCIe ports being starved of traffic.
> >> 
> >> Revert the whole thing until someone figures out what magic parameters
> >> allow QoS to work in a sensible manner, as a usable machine is somehow
> >> preferable to one that crashes efficiently.
> >> 
> >> Link: https://lore.kernel.org/all/apgeBNSiP01YfNcs@google.com
> >> Link: https://lore.kernel.org/all/86ld9d4h4n.wl-maz@kernel.org
> >> Signed-off-by: Marc Zyngier <maz@kernel.org>
> >> Cc: Georgi Djakov <djakov@kernel.org>
> >> Cc: Raviteja Laggyshetty <raviteja.laggyshetty@oss.qualcomm.com>
> >> Cc: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
> >> Cc: Abel Vesa <abelvesa@kernel.org>
> >> Cc: Bjorn Andersson <andersson@kernel.org>
> >> Cc: Mostafa Saleh <smostafa@google.com>
> >> Cc: Thorsten Leemhuis <regressions@leemhuis.info>
> >> ---
> >>   drivers/interconnect/qcom/x1e80100.c | 485 ---------------------------
> >>   1 file changed, 485 deletions(-)
> > 
> > Any update on applying this? These machines have been broken for the
> > past 4 release candidates, and it'd be great to get them back to a
> > working state.
> > 
> The revert is in linux-next already and i will propagate it as a fix in
> a couple of days. Thank you for the report and for sending the patch!

Ah, I hadn't looked into -next. Thanks for letting me know. I'm
looking forward to being able to use these machines with upstream
again!

	M.

-- 
Without deviation from the norm, progress is not possible.