Re: [V2] net/intel/e1000: reduce the optimization level for gcc > 11

[Thierry Herbelot <thierry.herbelot@6wind.com>]

On 10/10/25 15:20, Bruce Richardson wrote:
> On Mon, Oct 06, 2025 at 03:02:57PM +0200, Thierry Herbelot wrote:
>> The e1000 PMD stopped working under Ubuntu-24.04 (using gcc-13) when
>> compiled with -O3 (default level for all DPDK code). There is a crash
>> when starting testpmd:
>>
>>> (gdb) bt
>>> #0  rte_read32_relaxed (addr=0x1100800e00) at ../sources/lib/eal/include/generic/rte_io.h:290
>>> #1  rte_read32 (addr=0x1100800e00) at ../sources/lib/eal/include/generic/rte_io.h:345
>>> #2  e1000_read_addr (addr=0x1100800e00) at ../sources/drivers/net/intel/e1000/base/e1000_osdep.h:106
>>> #3  e1000_id_led_init_generic (hw=0x1586788c0) at ../sources/drivers/net/intel/e1000/base/e1000_mac.c:1844
>>> #4  0x000062aaf653c85f in e1000_init_hw_82540 (hw=0x1586788c0)
>>>      at ../sources/drivers/net/intel/e1000/base/e1000_82540.c:308
>>> #5  0x000062aaf6db8227 in em_hardware_init (hw=hw@entry=0x1586788c0)
>>>      at ../sources/drivers/net/intel/e1000/em_ethdev.c:920
>>> #6  0x000062aaf65340ff in em_hw_init (hw=0x1586788c0) at ../sources/drivers/net/intel/e1000/em_ethdev.c:445
>>> #7  eth_em_dev_init (eth_dev=eth_dev@entry=0x62aaff346000 <rte_eth_devices>)
>>>      at ../sources/drivers/net/intel/e1000/em_ethdev.c:314
>>> #8  0x000062aaf6db8b71 in rte_eth_dev_pci_generic_probe (private_data_size=11240,
>>>      dev_init=0x62aaf6db8310 <eth_em_dev_init>, pci_dev=0x62ab2853dd90) at ../sources/lib/ethdev/ethdev_pci.h:150
>>> #9  eth_em_pci_probe (pci_drv=<optimized out>, pci_dev=0x62ab2853dd90)
>>>      at ../sources/drivers/net/intel/e1000/em_ethdev.c:365
>>> #10 0x000062aaf646adf5 in rte_pci_probe_one_driver (dr=dr@entry=0x62aaf82d8020 <rte_em_pmd>,
>>>      dev=dev@entry=0x62ab2853dd90) at ../sources/drivers/bus/pci/pci_common.c:299
>>> #11 0x000062aaf6a15f7d in pci_probe_all_drivers (dev=0x62ab2853dd90) at ../sources/drivers/bus/pci/pci_common.c:383
>>> #12 pci_probe () at ../sources/drivers/bus/pci/pci_common.c:410
>>> #13 0x000062aaf7a485f3 in rte_bus_probe () at ../sources/lib/eal/common/eal_common_bus.c:84
>>> #14 0x000062aaf670585d in rte_eal_init (argc=argc@entry=146, argv=argv@entry=0x7fffca468898)
>>>      at ../sources/lib/eal/linux/eal.c:1253
>>
>> The crash is linked to the use of gcc-13: under Ubuntu-24.04 testpmd
>> compiled with gcc-11 from the same DPDK tree works as expected.
>>
>> The perfect solution would be for someone to investigate why the
>> PMD crashes. However, this depends on Maintainer availability.
>>
> Hi,
> 
> can you test with [1]. It's still a workaround while we investigate more,
> but a less severe one!

Hello,

Thanks for the quick turnaround.
The compilation is ongoing. I will post ASAP, when the test has run.

	Thierry>
> /Bruce
> 
> [1] https://patches.dpdk.org/project/dpdk/patch/20251010125848.965340-1-ciara.loftus@intel.com/

-- 
Thierry Herbelot