[dpdk-dev] [PATCH v3 00/40] Fix build on gcc8 and various bugs

[Andy Green]

On 05/10/2018 06:21 PM, Luca Boccassi wrote:
> On Thu, 2018-05-10 at 10:46 +0800, Andy Green wrote:
>> The following series gets current master able to build
>> itself, and allow lagopus to build against it, on Fedora 28 +
>> x86_64 using gcc 8.0.1.
>>
>> The first 17 patches have already been through two spins and
>> this time are corrected for all the comment (thanks to
>> everybody who commented) since v2, and have tested-by /
>> acked-bys applied.  The first workaround patch for the hash
>> function cast problem is dropped since something has already
>> been applied in master since yesterday to address it.
>>
>> The additional 23 patches are fixes for problems found
>> actually trying to build lagopus using current master.
>> These are almost entirely related to signed / unsigned
>> or truncation without explicit casts inside dpdk
>> headers.
>>
>> ---
>>
>> Andy Green (40):
>>        drivers/bus/pci: fix strncpy dangerous code
>>        drivers/bus/dpaa: fix inconsistent struct alignment
>>        drivers/net/axgbe: fix broken eeprom string comp
>>        drivers/net/nfp/nfpcore: fix strncpy misuse
>>        drivers/net/nfp/nfpcore: fix off-by-one and no NUL on strncpy
>> use
>>        drivers/net/nfp: don't memcpy out of source range
>>        drivers/net/nfp: fix buffer overflow in fw_name
>>        drivers/net/qede: fix strncpy constant and NUL
>>        drivers/net/qede: fix broken strncpy
>>        drivers/net/sfc: fix strncpy length
>>        drivers/net/sfc: fix strncpy size and NUL
>>        drivers/net/vdev: readlink inputs cannot be aliased
>>        drivers/net/vdev: fix 3 x strncpy misuse
>>        app/test-pmd: can't find include
>>        app/proc-info: fix sprintf overrun bug
>>        app/test-bbdev: test-bbdev: strcpy ok for allocated string
>>        app/test-bbdev: strcpy ok for allocated string
>>        rte_common.h: cast gcc builtin result to avoid complaints
>>        rte_memcpy.h: explicit tmp cast
>>        lib/librte_eal/common/include/rte_lcore.h: explicit cast for
>> signed change
>>        /lib/librte_eal/common/include/rte_random.h: stage cast from
>> uint64_t to long
>>        rte_spinlock.h: stack declarations before code
>>        rte_ring_generic.h: stack declarations before code
>>        rte_ring.h: remove signed type flipflopping
>>        rte_dev.h: stack declaration at top of own basic block
>>        rte_mbuf.h: avoid truncation warnings from inadvertant int16_t
>> to int promotion
>>        rte_mbuf.h: explicit casts for flipping between int16_t and
>> uint16_t
>>        rte_mbuf.h: make sure RTE_MIN compares same types
>>        rte_mbuf.h: explicit cast restricting ptrdiff to uint16_t
>>        rte_mbuf.h: explicit cast for size_t to uint32_t
>>        rte_mbuf.h: explicit casts to uint16_t to avoid truncation
>> warnings
>>        rte_byteorder.h: explicit cast for return promotion
>>        rte_ether.h: explicit cast avoiding truncation warning
>>        rte_ether.h: stack vars declared at top of function
>>        rte_ethdev.h: fix sign and scope of temp var
>>        rte_ethdev.h: explicit cast for return type
>>        rte_ethdev.h: explicit cast for truncation
>>        rte_hash_crc.h: stack vars declared at top of function
>>        rte_hash_crc.h: explicit casts for truncation
>>        rte_string_fns.h: explicit cast for int return to size_t
> 
> Hi,
> 
> I've built-tested this series on Debian Stretch (gcc 6.3) and Debian
> Sid (gcc 8.1).
> 
> The series builds fine with the default config, but the bnx2x and mlx5
> PMDs still have errors with gcc-8:

Yes I just built it with defconfig for x86_64 on Fedora 28 with default 
tools and cleared out everything that came up.

> /tmp/dpdk/drivers/net/bnx2x/bnx2x.c: In function 'bnx2x_alloc_hsi_mem':
> /tmp/dpdk/drivers/net/bnx2x/bnx2x.c:176:29: error: '%s' directive writing up to 31 bytes into a region of size between 15 and 25 [-Werror=format-overflow=]
>     sprintf(mz_name, "bnx2x%d_%s_%" PRIx64, sc->pcie_device, msg,
>                               ^~
> /tmp/dpdk/drivers/net/bnx2x/bnx2x.c:8874:7:
>     if (bnx2x_dma_alloc(sc, sizeof(union bnx2x_host_hc_status_block),
>         ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>         &fp->sb_dma, buf, RTE_CACHE_LINE_SIZE) != 0) {
>         ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> /tmp/dpdk/drivers/net/bnx2x/bnx2x.c:176:3: note: 'sprintf' output between 10 and 66 bytes into a destination of size 32
>     sprintf(mz_name, "bnx2x%d_%s_%" PRIx64, sc->pcie_device, msg,
>     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>      rte_get_timer_cycles());
>      ~~~~~~~~~~~~~~~~~~~~~~~
> /tmp/dpdk/drivers/net/bnx2x/bnx2x.c:173:29: error: '%s' directive writing up to 31 bytes into a region of size between 23 and 25 [-Werror=format-overflow=]
>     sprintf(mz_name, "bnx2x%d_%s_%" PRIx64, SC_ABS_FUNC(sc), msg,
>                               ^~
> /tmp/dpdk/drivers/net/bnx2x/bnx2x.c:8874:7:
>     if (bnx2x_dma_alloc(sc, sizeof(union bnx2x_host_hc_status_block),
>         ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>         &fp->sb_dma, buf, RTE_CACHE_LINE_SIZE) != 0) {
>         ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> /tmp/dpdk/drivers/net/bnx2x/bnx2x.c:173:3: note: 'sprintf' output between 10 and 58 bytes into a destination of size 32
>     sprintf(mz_name, "bnx2x%d_%s_%" PRIx64, SC_ABS_FUNC(sc), msg,
>     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>      rte_get_timer_cycles());
> 
> 
> /tmp/dpdk/drivers/net/mlx5/mlx5.c: In function 'mlx5_pci_probe':
> /tmp/dpdk/drivers/net/mlx5/mlx5.c:920:13: error: 'vf' may be used uninitialized in this function [-Werror=maybe-uninitialized]
>     config.vf = vf;
> 
> Hope this can be useful.

I think gcc 8.0.1 is capable to show that and I am willing to look at 
them.  But can you help me with exactly what changes you made so these 
things built and made trouble, compared to the defconfig I have used 
until now?

-Andy