The new IPSec offload code introduced a build error:
drivers/net/ethernet/mellanox/mlx5/core/en_accel/ipsec_rxtx.o: In function `mlx5e_ipsec_build_inverse_table':
ipsec_rxtx.c:(.text+0x556): undefined reference
Another patch was added on top to fix the build error, but
that introduced a new bug, as we now use the remainder of
the division rather than the result.
This makes it use the correct helper function instead.
Fixes: 5dfd87b67cd9 ("net/mlx5: IPSec, Fix 64-bit division on 32-bit builds")
Fixes: 2ac9cfe78223 ("net/mlx5e: IPSec, Add Innova IPSec offload TX data path")
Signed-off-by: Arnd Bergmann <[email protected]>
---
drivers/net/ethernet/mellanox/mlx5/core/en_accel/ipsec_rxtx.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_accel/ipsec_rxtx.c b/drivers/net/ethernet/mellanox/mlx5/core/en_accel/ipsec_rxtx.c
index 7d06c673851a..4614ddfa91eb 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_accel/ipsec_rxtx.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_accel/ipsec_rxtx.c
@@ -363,7 +363,6 @@ void mlx5e_ipsec_build_inverse_table(void)
{
u16 mss_inv;
u32 mss;
- u64 n;
/* Calculate 1/x inverse table for use in GSO data path.
* Using this table, we provide the IPSec accelerator with the value of
@@ -373,8 +372,7 @@ void mlx5e_ipsec_build_inverse_table(void)
*/
mlx5e_ipsec_inverse_table[1] = htons(0xFFFF);
for (mss = 2; mss < MAX_LSO_MSS; mss++) {
- n = 1ULL << 32;
- mss_inv = do_div(n, mss) >> 16;
+ mss_inv = div_u64(1ULL << 32, mss) >> 16;
mlx5e_ipsec_inverse_table[mss] = htons(mss_inv);
}
}
--
2.9.0
> -----Original Message-----
> From: Arnd Bergmann [mailto:[email protected]]
> Subject: [PATCH] net/mlx5: IPSec, fix 64-bit division correctly
>
> The new IPSec offload code introduced a build error:
>
> drivers/net/ethernet/mellanox/mlx5/core/en_accel/ipsec_rxtx.o: In function
> `mlx5e_ipsec_build_inverse_table':
> ipsec_rxtx.c:(.text+0x556): undefined reference
>
> Another patch was added on top to fix the build error, but
> that introduced a new bug, as we now use the remainder of
> the division rather than the result.
>
> This makes it use the correct helper function instead.
>
> Fixes: 5dfd87b67cd9 ("net/mlx5: IPSec, Fix 64-bit division on 32-bit
> builds")
> Fixes: 2ac9cfe78223 ("net/mlx5e: IPSec, Add Innova IPSec offload TX data
> path")
> Signed-off-by: Arnd Bergmann <[email protected]>
> ---
> drivers/net/ethernet/mellanox/mlx5/core/en_accel/ipsec_rxtx.c | 4 +---
> 1 file changed, 1 insertion(+), 3 deletions(-)
>
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_accel/ipsec_rxtx.c
> b/drivers/net/ethernet/mellanox/mlx5/core/en_accel/ipsec_rxtx.c
> index 7d06c673851a..4614ddfa91eb 100644
> --- a/drivers/net/ethernet/mellanox/mlx5/core/en_accel/ipsec_rxtx.c
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_accel/ipsec_rxtx.c
> @@ -363,7 +363,6 @@ void mlx5e_ipsec_build_inverse_table(void)
> {
> u16 mss_inv;
> u32 mss;
> - u64 n;
>
> /* Calculate 1/x inverse table for use in GSO data path.
> * Using this table, we provide the IPSec accelerator with the value
> of
> @@ -373,8 +372,7 @@ void mlx5e_ipsec_build_inverse_table(void)
> */
> mlx5e_ipsec_inverse_table[1] = htons(0xFFFF);
> for (mss = 2; mss < MAX_LSO_MSS; mss++) {
> - n = 1ULL << 32;
> - mss_inv = do_div(n, mss) >> 16;
> + mss_inv = div_u64(1ULL << 32, mss) >> 16;
Thanks Arnd,
:o
I'm surprised... let me check this...
> mlx5e_ipsec_inverse_table[mss] = htons(mss_inv);
> }
> }
> --
> 2.9.0
> -----Original Message-----
> From: Arnd Bergmann [mailto:[email protected]]
> Subject: [PATCH] net/mlx5: IPSec, fix 64-bit division correctly
>
> The new IPSec offload code introduced a build error:
>
> drivers/net/ethernet/mellanox/mlx5/core/en_accel/ipsec_rxtx.o: In function
> `mlx5e_ipsec_build_inverse_table':
> ipsec_rxtx.c:(.text+0x556): undefined reference
>
> Another patch was added on top to fix the build error, but
> that introduced a new bug, as we now use the remainder of
> the division rather than the result.
>
> This makes it use the correct helper function instead.
>
> Fixes: 5dfd87b67cd9 ("net/mlx5: IPSec, Fix 64-bit division on 32-bit
> builds")
> Fixes: 2ac9cfe78223 ("net/mlx5e: IPSec, Add Innova IPSec offload TX data
> path")
> Signed-off-by: Arnd Bergmann <[email protected]>
This is a good fix. Values are now generated correctly.
Sorry for the mixup.
Thank you Arnd!
Reviewed-by: Ilan Tayari <[email protected]>
On Mon, 2017-07-10 at 10:24 +0000, Ilan Tayari wrote:
> > -----Original Message-----
> > From: Arnd Bergmann [mailto:[email protected]]
> > Subject: [PATCH] net/mlx5: IPSec, fix 64-bit division correctly
> >
> > The new IPSec offload code introduced a build error:
> >
> > drivers/net/ethernet/mellanox/mlx5/core/en_accel/ipsec_rxtx.o: In function
> > `mlx5e_ipsec_build_inverse_table':
> > ipsec_rxtx.c:(.text+0x556): undefined reference
> >
> > Another patch was added on top to fix the build error, but
> > that introduced a new bug, as we now use the remainder of
> > the division rather than the result.
Is it possible to return noise in mlx5e_ipsec_mss_inv ?
What clamps skb_shinfo(skb)->gso_size to MAX_LSO
(the size of inverse_table)?
#define MAX_LSO_MSS 2048
static __be16 mlx5e_ipsec_inverse_table[MAX_LSO_MSS];
static inline __be16 mlx5e_ipsec_mss_inv(struct sk_buff *skb)
{
return mlx5e_ipsec_inverse_table[skb_shinfo(skb)->gso_size];
}
From: Arnd Bergmann <[email protected]>
Date: Mon, 10 Jul 2017 11:37:51 +0200
> The new IPSec offload code introduced a build error:
>
> drivers/net/ethernet/mellanox/mlx5/core/en_accel/ipsec_rxtx.o: In function `mlx5e_ipsec_build_inverse_table':
> ipsec_rxtx.c:(.text+0x556): undefined reference
>
> Another patch was added on top to fix the build error, but
> that introduced a new bug, as we now use the remainder of
> the division rather than the result.
>
> This makes it use the correct helper function instead.
>
> Fixes: 5dfd87b67cd9 ("net/mlx5: IPSec, Fix 64-bit division on 32-bit builds")
> Fixes: 2ac9cfe78223 ("net/mlx5e: IPSec, Add Innova IPSec offload TX data path")
> Signed-off-by: Arnd Bergmann <[email protected]>
Applied, thanks.