[dpdk-dev] Segmentation fault in rte_eal_hugepage_attach
> The most likely cause of failure in mapping the memory is that the range > requested is already used by another memory mapping in the processes address > space. Two possible paths to look at this: > 1) examine the /proc//maps file for the secondary process Brilliant advice, Bruce! This was indeed the cause. The secondary process had some shared libraries mapped right in the middle of the viable 1G range. The most expedient workaround was to link the primary process against those same shared libraries, as you advised Etai here: http://www.dpdk.info/ml/archives/dev/2014-April/001829.html Perhaps not the most sustainable solution... Thank you very much, Rick LaMont | After forty years of toil Dot C Software, Inc. | He just up and walked away
[dpdk-dev] Segmentation fault in rte_eal_hugepage_attach
On Tue, Dec 16, 2014 at 11:12:36PM -0500, Rick LaMont wrote: > My DPDK application works fine when it's the primary process but crashes > whenever --proc-type=secondary. The segmentation fault occurs in this call > to mmap() within rte_eal_hugepage_attach(): > > /* > * fdzero is mmapped to get a contiguous block of virtual > * addresses of the appropriate memseg size. > * use mmap to get identical addresses as the primary process. > */ > base_addr = mmap(mcfg->memseg[s].addr, mcfg->memseg[s].len, > PROT_READ, MAP_PRIVATE | MAP_FIXED, fd_zero, 0); > > I've confirmed that addr and len match the values in rte_eal_hugepage_init() > of the primary process (1 gigabyte). The target platform is a 32-bit embedded > system running a Yocto distribution. I've confirmed that other applications > such as mp_simple work as both primary and secondary on the same platform. > The problem only occurs with a larger application to which I'm adding DPDK > capabilities. > > Any advice on how to troubleshoot this? I've been looking at it for a week > already and am running out of ideas for things to test. > > Thanks, > > > Rick LaMont | The storm that I thought would blow over > Dot C Software, Inc. | Clouds the light of the love that I found Hi, getting multi-process support working on 32-bits is a lot more difficult than with 64-bit due to the reduced addresss space range available. The most likely cause of failure in mapping the memory is that the range requested is already used by another memory mapping in the processes address space. Two possible paths to look at this: 1) examine the /proc//maps file for the secondary process to see what is using the address range and if it's something you can do something about. 2) If you do find a free 1G range inside the secondary process address space, you can try hinting that address to the primary process to see if it can map the memory there, allowing the secondary process to duplicate. [See "base-virtaddr" EAL option] Regards, /Bruce
[dpdk-dev] Segmentation fault in rte_eal_hugepage_attach
My DPDK application works fine when it's the primary process but crashes whenever --proc-type=secondary. The segmentation fault occurs in this call to mmap() within rte_eal_hugepage_attach(): /* * fdzero is mmapped to get a contiguous block of virtual * addresses of the appropriate memseg size. * use mmap to get identical addresses as the primary process. */ base_addr = mmap(mcfg->memseg[s].addr, mcfg->memseg[s].len, PROT_READ, MAP_PRIVATE | MAP_FIXED, fd_zero, 0); I've confirmed that addr and len match the values in rte_eal_hugepage_init() of the primary process (1 gigabyte). The target platform is a 32-bit embedded system running a Yocto distribution. I've confirmed that other applications such as mp_simple work as both primary and secondary on the same platform. The problem only occurs with a larger application to which I'm adding DPDK capabilities. Any advice on how to troubleshoot this? I've been looking at it for a week already and am running out of ideas for things to test. Thanks, Rick LaMont | The storm that I thought would blow over Dot C Software, Inc. | Clouds the light of the love that I found