Re: [PATCH iwl-next] ixgbe: fix ITR value overflow in adaptive interrupt throttling

Simon Horman
2026-04-06T14:06:21Z

On Fri, Apr 03, 2026 at 04:12:02PM +0000, Loktionov, Aleksandr wrote:
>
>
> > -----Original Message-----
> > From: Simon Horman <horms@kernel.org>
> > Sent: Friday, April 3, 2026 3:19 PM
> > To: Loktionov, Aleksandr <aleksandr.loktionov@intel.com>
> > Cc: intel-wired-lan@lists.osuosl.org; Nguyen, Anthony L
> > <anthony.l.nguyen@intel.com>; netdev@vger.kernel.org
> > Subject: Re: [PATCH iwl-next] ixgbe: fix ITR value overflow in
> > adaptive interrupt throttling
> >
> > On Fri, Mar 27, 2026 at 08:30:45AM +0100, Aleksandr Loktionov wrote:
> > > ixgbe_update_itr() packs a mode flag (IXGBE_ITR_ADAPTIVE_LATENCY,
> > bit
> > > 7) and a usecs delay (bits [6:0]) into an unsigned int, then stores
> > it
> > > in ring_container->itr which is u8. Values above 0xFF wrap,
> > > corrupting both the delay and the mode-flag on the next readback.
> > >
> > > Separate the mode bits from the usecs sub-field; clamp only the
> > latter
> > > to [0, IXGBE_ITR_ADAPTIVE_LATENCY - 1] via min_t(unsigned int, ...)
> > so
> > > overflow cannot bleed into bit 7. Add a WARN_ONCE() when the raw
> > > usecs value exceeds U8_MAX so out-of-range ITR computations are
> > > visible in dmesg during development and testing.
> > >
> > > Fixes: b4ded8327fea ("ixgbe: Update adaptive ITR algorithm")
> > > Signed-off-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
> >
> > Somehow - perhaps because there is no m/n notation present in the []
> > in the subject - Patchwork has treated each patch in this series as
> > it's own patch-set.
> >
> > And in the case of this patch, it didn't apply - I assume because in
> > order to do so an earlier patch in the series needs to be present.
> >
> > So CI didn't run on this patch :(
>
> Good day, Simon
>
> I have a bunch of simple /* independent */ patches for submission every week.
> Whis way you'd recommend to send them to ease /* and accelerate review */ ?
>
> 1. submit one by one
> 2. submit as a batch by one git command (with the same internal main ID tag internally)
> 3. imagine a cover latter and submit as a patch-set

Hi Aleksandr,

I would suggest 3 and lean towards small batches.