[PATCH v3] vhost/crypto: fix build with GCC 12

[Poczatek, Jakub]

Hey everyone, 

When running a Virtio performance test on a VM using VHost with this patch applied,
VHost gives the following error message: 

> VHOST_CONFIG: (/tmp/vhost) read message VHOST_USER_SET_FEATURES
> VHOST_CONFIG: (/tmp/vhost) negotiated Virtio features: 0x0
> VHOST_CONFIG: (/tmp/vhost) read message VHOST_USER_SET_MEM_TABLE
> VHOST_CONFIG: (/tmp/vhost) guest memory region size: 0x80000000
> VHOST_CONFIG: (/tmp/vhost)       guest physical addr: 0x0
> VHOST_CONFIG: (/tmp/vhost)       guest virtual  addr: 0x7f17c0000000
> VHOST_CONFIG: (/tmp/vhost)       host  virtual  addr: 0x7f94c0000000
> VHOST_CONFIG: (/tmp/vhost)       mmap addr : 0x7f94c0000000
> VHOST_CONFIG: (/tmp/vhost)       mmap size : 0x80000000
> VHOST_CONFIG: (/tmp/vhost)       mmap align: 0x40000000
> VHOST_CONFIG: (/tmp/vhost)       mmap off  : 0x0
> VHOST_CONFIG: (/tmp/vhost) read message VHOST_USER_SET_VRING_NUM
> VHOST_CONFIG: (/tmp/vhost) read message VHOST_USER_SET_VRING_BASE
> VHOST_CONFIG: (/tmp/vhost) vring base idx:0 last_used_idx:0 last_avail_idx:0.
> VHOST_CONFIG: (/tmp/vhost) read message VHOST_USER_SET_VRING_ADDR
> VHOST_CONFIG: (/tmp/vhost) read message VHOST_USER_SET_VRING_KICK
> VHOST_CONFIG: (/tmp/vhost) vring kick idx:0 file:37
> VHOST_CONFIG: (/tmp/vhost) reallocated virtqueue on node 1
> VHOST_CONFIG: (/tmp/vhost) reallocated device on node 1
> VHOST_CONFIG: (/tmp/vhost) virtio is now ready for processing.
> USER1: New Vhost-crypto Device /tmp/vhost, Device ID 0
> VHOST_CONFIG: (/tmp/vhost) read message VHOST_USER_SET_VRING_CALL
> VHOST_CONFIG: (/tmp/vhost) vring call idx:0 file:38
> USER1: [VHOST-Crypto]: Session 1 created for vdev 0.
> USER1: [VHOST-Crypto]: Incorrect virtio descriptor
> USER1: [VHOST-Crypto]: Failed to process sym request
> USER1: [VHOST-Crypto]: Incorrect virtio descriptor
> USER1: [VHOST-Crypto]: Failed to process sym request

Due to this, performance test hangs and never finishes. 

Kind Regards, 
Jakub Poczatek

-----Original Message-----
From: Maxime Coquelin <maxime.coquelin at redhat.com> 
Sent: Tuesday 21 June 2022 10:31
To: David Marchand <david.marchand at redhat.com>; dev at dpdk.org
Cc: stable at dpdk.org; Xia, Chenbo <chenbo.xia at intel.com>; Zhang, Roy Fan <roy.fan.zhang at intel.com>
Subject: Re: [PATCH v3] vhost/crypto: fix build with GCC 12



On 6/16/22 16:46, David Marchand wrote:
> GCC 12 raises the following warning:
> 
> In file included from ../lib/mempool/rte_mempool.h:46,
>                   from ../lib/mbuf/rte_mbuf.h:38,
>                   from ../lib/vhost/vhost_crypto.c:7:
> ../lib/vhost/vhost_crypto.c: In function ‘rte_vhost_crypto_fetch_requests’:
> ../lib/eal/x86/include/rte_memcpy.h:371:9: warning: array subscript 1 is
>       outside array bounds of ‘struct virtio_crypto_op_data_req[1]’
>       [-Warray-bounds]
>    371 | rte_mov32((uint8_t *)dst + 3 * 32, (const uint8_t *)src + 3 * 32);
>        | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> ../lib/vhost/vhost_crypto.c:1178:42: note: while referencing ‘req’
>   1178 |         struct virtio_crypto_op_data_req req;
>        |                                          ^~~
> 
> Split this function and separate the per descriptor copy.
> This makes the code clearer, and the compiler happier.
> 
> Note: logs for errors have been moved to callers to avoid duplicates.
> 
> Fixes: 3c79609fda7c ("vhost/crypto: handle virtually non-contiguous buffers")
> Cc: stable at dpdk.org
> 
> Signed-off-by: David Marchand <david.marchand at redhat.com>
> ---
> Changes since v2:
> - fixed 32-bits build,
> 
> Changes since v1:
> - refactored copy function,
> 
> ---
>   lib/vhost/vhost_crypto.c | 123 +++++++++++++++------------------------
>   1 file changed, 46 insertions(+), 77 deletions(-)
> 

Applied to dpdk-next-virtio/main.

Thanks,
Maxime