continuing on the back trace: #8 [ffff880092791dd0] page_fault at ffffffff81747e98 [exception RIP: kmem_cache_alloc+102] RIP: ffffffff8119c316 RSP: ffff880092791e88 RFLAGS: 00010286 RAX: 0000000000000000 RBX: ffffffffffffffea RCX: 00000000260000be RDX: 00000000260000bd RSI: 00000000000000d0 RDI: 00000000000173c0 RBP: ffff880092791ed8 R8: ffff880c0bb173c0 R9: 0000000000001165 R10: 00007f2e4ac88dcc R11: 0000000000000246 R12: ffff880c0b403800 R13: ffff880ce78ccc00 R14: ffffffff8108f636 R15: 00000000000000d0 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 #9 [ffff880092791ee0] prepare_creds at ffffffff8108f636 #10 [ffff880092791f00] sys_faccessat at ffffffff811b22b4 #11 [ffff880092791f70] sys_access at ffffffff811b24b8
In "prepare_creds" execution we called "kmem_cache_alloc" which triggered a page fault that was handled by the same task... (so we had a page fault inside kernel context). With the rest of the back trace: #3 [ffff880092791bd0] no_context at ffffffff8172dd02 #4 [ffff880092791c20] __bad_area_nosemaphore at ffffffff8172dee4 #5 [ffff880092791c80] bad_area_nosemaphore at ffffffff8172df16 #6 [ffff880092791c90] __do_page_fault at ffffffff8174bc12 #7 [ffff880092791da0] do_page_fault at ffffffff8174bde7 But kernel couldn't handle this page fault .. things that might have happened: 0) error code can be PF_RSVD, PF_USER or PF_PROT (to be checked) if not 0.1) address for the page fault is not inside vmalloc area (return -1) (since its a page fault for a virtual address) 1) this wasn't a spurious fault (for sure) (caused by cpu walking the page table by itself) kernel oops with no_context... Im still working on this.. will come back here with comments soon. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1389787 Title: 3.11 memory consumption leads to HANG (not sure if 3.13 suffers from this). To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1389787/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
