diff mbox series

[net-queue,v3] virtchnl: Fix layout of RSS structures

Message ID 20210128181702.1941534-1-anthony.l.nguyen@intel.com
State Accepted
Delegated to: Anthony Nguyen
Headers show
Series [net-queue,v3] virtchnl: Fix layout of RSS structures | expand

Commit Message

Tony Nguyen Jan. 28, 2021, 6:17 p.m. UTC 
From: Norbert Ciosek <norbertx.ciosek@intel.com>

Remove padding from RSS structures. Previous layout
could lead to unwanted compiler optimizations
in loops when iterating over key and lut arrays.

Fixes: 65ece6de0114 ("virtchnl: Add missing explicit padding to structures")
Signed-off-by: Norbert Ciosek <norbertx.ciosek@intel.com>
---
v3: Removed footer
v2: Removed padding instead of moving "key" and "lut" fields
at the end of RSS structures.

 include/linux/avf/virtchnl.h | 2 --
 1 file changed, 2 deletions(-)

Comments

Jankowski, Konrad0 March 19, 2021, 10:20 a.m. UTC | #1 
> -----Original Message-----
> From: Intel-wired-lan <intel-wired-lan-bounces@osuosl.org> On Behalf Of
> Tony Nguyen
> Sent: czwartek, 28 stycznia 2021 19:17
> To: intel-wired-lan@lists.osuosl.org
> Cc: Ciosek, NorbertX <norbertx.ciosek@intel.com>
> Subject: [Intel-wired-lan] [net-queue v3] virtchnl: Fix layout of RSS structures
> 
> From: Norbert Ciosek <norbertx.ciosek@intel.com>
> 
> Remove padding from RSS structures. Previous layout could lead to
> unwanted compiler optimizations in loops when iterating over key and lut
> arrays.
> 
> Fixes: 65ece6de0114 ("virtchnl: Add missing explicit padding to structures")
> Signed-off-by: Norbert Ciosek <norbertx.ciosek@intel.com>
> ---
> v3: Removed footer
> v2: Removed padding instead of moving "key" and "lut" fields at the end of
> RSS structures.
> 
>  include/linux/avf/virtchnl.h | 2 --
>  1 file changed, 2 deletions(-)
> 
> diff --git a/include/linux/avf/virtchnl.h b/include/linux/avf/virtchnl.h index
> 40bad71865ea..532bcbfc4716 100644
> --- a/include/linux/avf/virtchnl.h
> +++ b/include/linux/avf/virtchnl.h
> @@ -476,7 +476,6 @@ struct virtchnl_rss_key {
>  	u16 vsi_id;
>  	u16 key_len;
>  	u8 key[1];         /* RSS hash key, packed bytes */
> -	u8 pad[1];
>  };
> 
>  VIRTCHNL_CHECK_STRUCT_LEN(6, virtchnl_rss_key); @@ -485,7 +484,6 @@
> struct virtchnl_rss_lut {
>  	u16 vsi_id;
>  	u16 lut_entries;
>  	u8 lut[1];        /* RSS lookup table */
> -	u8 pad[1];
>  };
> 
>  VIRTCHNL_CHECK_STRUCT_LEN(6, virtchnl_rss_lut);
> --
> 2.26.2
> 
Tested-by: Konrad Jankowski <konrad0.jankowski@intel.com>
diff mbox series

Patch

diff --git a/include/linux/avf/virtchnl.h b/include/linux/avf/virtchnl.h
index 40bad71865ea..532bcbfc4716 100644
--- a/include/linux/avf/virtchnl.h
+++ b/include/linux/avf/virtchnl.h
@@ -476,7 +476,6 @@  struct virtchnl_rss_key {
 	u16 vsi_id;
 	u16 key_len;
 	u8 key[1];         /* RSS hash key, packed bytes */
-	u8 pad[1];
 };
 
 VIRTCHNL_CHECK_STRUCT_LEN(6, virtchnl_rss_key);
@@ -485,7 +484,6 @@  struct virtchnl_rss_lut {
 	u16 vsi_id;
 	u16 lut_entries;
 	u8 lut[1];        /* RSS lookup table */
-	u8 pad[1];
 };
 
 VIRTCHNL_CHECK_STRUCT_LEN(6, virtchnl_rss_lut);