{"id":833387,"url":"http://patchwork.ozlabs.org/api/1.2/covers/833387/?format=json","web_url":"http://patchwork.ozlabs.org/project/netdev/cover/1509633431-2184-1-git-send-email-josef@toxicpanda.com/","project":{"id":7,"url":"http://patchwork.ozlabs.org/api/1.2/projects/7/?format=json","name":"Linux network development","link_name":"netdev","list_id":"netdev.vger.kernel.org","list_email":"netdev@vger.kernel.org","web_url":null,"scm_url":null,"webscm_url":null,"list_archive_url":"","list_archive_url_format":"","commit_url_format":""},"msgid":"<1509633431-2184-1-git-send-email-josef@toxicpanda.com>","list_archive_url":null,"date":"2017-11-02T14:37:09","name":"[0/2,v4] Add the ability to do BPF directed error injection","submitter":{"id":72383,"url":"http://patchwork.ozlabs.org/api/1.2/people/72383/?format=json","name":"Josef Bacik","email":"josef@toxicpanda.com"},"mbox":"http://patchwork.ozlabs.org/project/netdev/cover/1509633431-2184-1-git-send-email-josef@toxicpanda.com/mbox/","series":[{"id":11520,"url":"http://patchwork.ozlabs.org/api/1.2/series/11520/?format=json","web_url":"http://patchwork.ozlabs.org/project/netdev/list/?series=11520","date":"2017-11-02T14:37:10","name":"Add the ability to do BPF directed error injection","version":1,"mbox":"http://patchwork.ozlabs.org/series/11520/mbox/"}],"comments":"http://patchwork.ozlabs.org/api/covers/833387/comments/","headers":{"Return-Path":"","X-Original-To":"patchwork-incoming@ozlabs.org","Delivered-To":"patchwork-incoming@ozlabs.org","Authentication-Results":["ozlabs.org;\n\tspf=none (mailfrom) smtp.mailfrom=vger.kernel.org\n\t(client-ip=209.132.180.67; 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Some subystems (block, memory) have ways to\ninject errors, but they are random so it's hard to get reproduceable results.\n\nWith BPF we can add determinism to our error injection. We can use kprobes and\nother things to verify we are injecting errors at the exact case we are trying\nto test. This patch gives us the tool to actual do the error injection part.\nIt is very simple, we just set the return value of the pt_regs we're given to\nwhatever we provide, and then override the PC with a dummy function that simply\nreturns.\n\nRight now this only works on x86, but it would be simple enough to expand to\nother architectures. Thanks,\n\nJosef"}