Hi, Lucero, Thomas This patch set will cause deadlock during memory initialization. rte_memseg_walk and try_expand_heap both will lock the file &mcfg->memory_hotplug_lock. So dead lock will occur.
#0 rte_memseg_walk #1 <-rte_eal_check_dma_mask #2 <-alloc_pages_on_heap #3 <-try_expand_heap_primary #4 <-try_expand_heap Log as following: EAL: TSC frequency is ~2494156 KHz EAL: Master lcore 0 is ready (tid=7ffff7fe3c00;cpuset=[0]) [New Thread 0x7ffff5e0d700 (LWP 330350)] EAL: lcore 1 is ready (tid=7ffff5e0d700;cpuset=[1]) EAL: Trying to obtain current memory policy. EAL: Setting policy MPOL_PREFERRED for socket 0 EAL: Restoring previous memory policy: 0 Could you have a check on this? A lot of test cases in our validation team fail because of this. Thanks a lot! BRs Lei > -----Original Message----- > From: dev [mailto:dev-boun...@dpdk.org] On Behalf Of Thomas Monjalon > Sent: Monday, October 29, 2018 5:04 AM > To: Alejandro Lucero <alejandro.luc...@netronome.com> > Cc: dev@dpdk.org > Subject: Re: [dpdk-dev] [PATCH v3 0/6] use IOVAs check based on DMA > mask > > 05/10/2018 14:45, Alejandro Lucero: > > I sent a patchset about this to be applied on 17.11 stable. The memory > > code has had main changes since that version, so here it is the patchset > > adjusted to current master repo. > > > > This patchset adds, mainly, a check for ensuring IOVAs are within a > > restricted range due to addressing limitations with some devices. There > > are two known cases: NFP and IOMMU VT-d emulation. > > > > With this check IOVAs out of range are detected and PMDs can abort > > initialization. For the VT-d case, IOVA VA mode is allowed as long as > > IOVAs are within the supported range, avoiding to forbid IOVA VA by > > default. > > > > For the addressing limitations known cases, there are just 40(NFP) or > > 39(VT-d) bits for handling IOVAs. When using IOVA PA, those limitations > > imply 1TB(NFP) or 512M(VT-d) as upper limits, which is likely enough for > > most systems. With machines using more memory, the added check will > > ensure IOVAs within the range. > > > > With IOVA VA, and because the way the Linux kernel serves mmap calls > > in 64 bits systems, 39 or 40 bits are not enough. It is possible to > > give an address hint with a lower starting address than the default one > > used by the kernel, and then ensuring the mmap uses that hint or hint plus > > some offset. With 64 bits systems, the process virtual address space is > > large enoguh for doing the hugepages mmaping within the supported > range > > when those addressing limitations exist. This patchset also adds a change > > for using such a hint making the use of IOVA VA a more than likely > > possibility when there are those addressing limitations. > > > > The check is not done by default but just when it is required. This > > patchset adds the check for NFP initialization and for setting the IOVA > > mode is an emulated VT-d is detected. Also, because the recent patchset > > adding dynamic memory allocation, the check is also invoked for ensuring > > the new memsegs are within the required range. > > > > This patchset could be applied to stable 18.05. > > Applied, thanks > > >
