All of lore.kernel.org
 help / color / mirror / Atom feed
From: Leon Romanovsky <leon@kernel.org>
To: Jesse Brandeburg <jesse.brandeburg@intel.com>
Cc: netdev@vger.kernel.org, intel-wired-lan@lists.osuosl.org,
	Przemek Kitszel <przemyslaw.kitszel@intel.com>
Subject: Re: [Intel-wired-lan] [PATCH iwl-net v2] ice: fix receive buffer size miscalculation
Date: Sun, 13 Aug 2023 12:03:13 +0300	[thread overview]
Message-ID: <20230813090313.GG7707@unreal> (raw)
In-Reply-To: <20230810235110.440553-1-jesse.brandeburg@intel.com>

On Thu, Aug 10, 2023 at 04:51:10PM -0700, Jesse Brandeburg wrote:
> The driver is misconfiguring the hardware for some values of MTU such that
> it could use multiple descriptors to receive a packet when it could have
> simply used one.
> 
> Change the driver to use a round-up instead of the result of a shift, as
> the shift can truncate the lower bits of the size, and result in the
> problem noted above. It also aligns this driver with similar code in i40e.
> 
> The insidiousness of this problem is that everything works with the wrong
> size, it's just not working as well as it could, as some MTU sizes end up
> using two or more descriptors, and there is no way to tell that is
> happening without looking at ice_trace or a bus analyzer.
> 
> Fixes: efc2214b6047 ("ice: Add support for XDP")
> Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
> Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
> ---
> v2: added fixes tag pointing to the last time this line was modified in
> v5.5 instead of pointing back to the introduction of the driver.
> ---
>  drivers/net/ethernet/intel/ice/ice_base.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 

Thanks,
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
_______________________________________________
Intel-wired-lan mailing list
Intel-wired-lan@osuosl.org
https://lists.osuosl.org/mailman/listinfo/intel-wired-lan

WARNING: multiple messages have this Message-ID (diff)
From: Leon Romanovsky <leon@kernel.org>
To: Jesse Brandeburg <jesse.brandeburg@intel.com>
Cc: intel-wired-lan@lists.osuosl.org, netdev@vger.kernel.org,
	Przemek Kitszel <przemyslaw.kitszel@intel.com>
Subject: Re: [PATCH iwl-net v2] ice: fix receive buffer size miscalculation
Date: Sun, 13 Aug 2023 12:03:13 +0300	[thread overview]
Message-ID: <20230813090313.GG7707@unreal> (raw)
In-Reply-To: <20230810235110.440553-1-jesse.brandeburg@intel.com>

On Thu, Aug 10, 2023 at 04:51:10PM -0700, Jesse Brandeburg wrote:
> The driver is misconfiguring the hardware for some values of MTU such that
> it could use multiple descriptors to receive a packet when it could have
> simply used one.
> 
> Change the driver to use a round-up instead of the result of a shift, as
> the shift can truncate the lower bits of the size, and result in the
> problem noted above. It also aligns this driver with similar code in i40e.
> 
> The insidiousness of this problem is that everything works with the wrong
> size, it's just not working as well as it could, as some MTU sizes end up
> using two or more descriptors, and there is no way to tell that is
> happening without looking at ice_trace or a bus analyzer.
> 
> Fixes: efc2214b6047 ("ice: Add support for XDP")
> Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
> Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
> ---
> v2: added fixes tag pointing to the last time this line was modified in
> v5.5 instead of pointing back to the introduction of the driver.
> ---
>  drivers/net/ethernet/intel/ice/ice_base.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 

Thanks,
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>

  reply	other threads:[~2023-08-13  9:03 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-08-10 23:51 [Intel-wired-lan] [PATCH iwl-net v2] ice: fix receive buffer size miscalculation Jesse Brandeburg
2023-08-10 23:51 ` Jesse Brandeburg
2023-08-13  9:03 ` Leon Romanovsky [this message]
2023-08-13  9:03   ` Leon Romanovsky
2023-08-17  5:10 ` [Intel-wired-lan] " Pucha, HimasekharX Reddy
2023-08-17  5:10   ` Pucha, HimasekharX Reddy

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20230813090313.GG7707@unreal \
    --to=leon@kernel.org \
    --cc=intel-wired-lan@lists.osuosl.org \
    --cc=jesse.brandeburg@intel.com \
    --cc=netdev@vger.kernel.org \
    --cc=przemyslaw.kitszel@intel.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.