On 15/08/2016 18:23, Harris, James R wrote: > >> -----Original Message----- >> From: dev [mailto:dev-bounces at dpdk.org] On Behalf Of Thomas Monjalon >> Sent: Thursday, August 11, 2016 12:05 AM >> To: users at dpdk.org; dev at dpdk.org; Gonzalez Monroy, Sergio; Richardson, >> Bruce >> Cc: Verkamp, Daniel >> Subject: Re: [dpdk-dev] [dpdk-users] rte_zmalloc() returning non-zeroed >> memory on FreeBSD >> >> Hi, >> >> 2016-08-10 23:30, Verkamp, Daniel: >>> It seems that with DPDK 16.07, rte_zmalloc() and related functions no >>> longer return zeroed memory reliably on FreeBSD. >>> >>> I notice that commit b78c9175118f7d61022ddc5c62ce54a1bd73cea5 ("mem: >> do >>> not zero out memory on zmalloc") removed the explicit memset() that >> used >>> to ensure the buffer was zeroed; its log message says: >>> >>> "Zeroing out memory on rte_zmalloc_socket is not required anymore since >>> all allocated memory is already zeroed." >> On Linux, the memory is zeroed by the kernel. >> Then the zero value is maintained in the rte_malloc pool by rte_free. >> >>> However, I don't see how this is guaranteed (at least for FreeBSD), and >>> it is not true in practice. I've attached a minimized reproducer program - >>> running it twice in a row fails reliably for me. >>> >>> Is there a missing step in FreeBSD, or is it a more general problem for >>> other platforms? >> I guess the initial value from the kernel has been verified only on Linux. >> We could re-add a memset for FreeBSD. > The problem is that the FreeBSD contigmem driver does not re-zero the huge > pages each time they are mmap'd - they are only zeroed when contigmem > initially loads. I will push a patch for this shortly.
So that is the case where we run the app more than once, right? I missed that, I only ran it once. Sergio
