mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-15 05:56:55 +07:00
b9e03857f2
Linux's fault injection framework provides a systematic way to support error injection via debugfs in the /sys/kernel/debug directory. This patch uses the framework to add error injection to NVMe driver. The fault injection source code is stored in a separate file and only linked if CONFIG_FAULT_INJECTION_DEBUG_FS kernel config is selected. Once the error injection is enabled, NVME_SC_INVALID_OPCODE with no retry will be injected into the nvme_end_request. Users can change the default status code and no retry flag via debufs. Following example shows how to enable and inject an error. For more examples, refer to Documentation/fault-injection/nvme-fault-injection.txt How to enable nvme fault injection: First, enable CONFIG_FAULT_INJECTION_DEBUG_FS kernel config, recompile the kernel. After booting up the kernel, do the following. How to inject an error: mount /dev/nvme0n1 /mnt echo 1 > /sys/kernel/debug/nvme0n1/fault_inject/times echo 100 > /sys/kernel/debug/nvme0n1/fault_inject/probability cp a.file /mnt Expected Result: cp: cannot stat ‘/mnt/a.file’: Input/output error Message from dmesg: FAULT_INJECTION: forcing a failure. name fault_inject, interval 1, probability 100, space 0, times 1 CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.15.0-rc8+ #2 Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006 Call Trace: <IRQ> dump_stack+0x5c/0x7d should_fail+0x148/0x170 nvme_should_fail+0x2f/0x50 [nvme_core] nvme_process_cq+0xe7/0x1d0 [nvme] nvme_irq+0x1e/0x40 [nvme] __handle_irq_event_percpu+0x3a/0x190 handle_irq_event_percpu+0x30/0x70 handle_irq_event+0x36/0x60 handle_fasteoi_irq+0x78/0x120 handle_irq+0xa7/0x130 ? tick_irq_enter+0xa8/0xc0 do_IRQ+0x43/0xc0 common_interrupt+0xa2/0xa2 </IRQ> RIP: 0010:native_safe_halt+0x2/0x10 RSP: 0018:ffffffff82003e90 EFLAGS: 00000246 ORIG_RAX: ffffffffffffffdd RAX: ffffffff817a10c0 RBX: ffffffff82012480 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 000000008e38ce64 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff82012480 R13: ffffffff82012480 R14: 0000000000000000 R15: 0000000000000000 ? __sched_text_end+0x4/0x4 default_idle+0x18/0xf0 do_idle+0x150/0x1d0 cpu_startup_entry+0x6f/0x80 start_kernel+0x4c4/0x4e4 ? set_init_arg+0x55/0x55 secondary_startup_64+0xa5/0xb0 print_req_error: I/O error, dev nvme0n1, sector 9240 EXT4-fs error (device nvme0n1): ext4_find_entry:1436: inode #2: comm cp: reading directory lblock 0 Signed-off-by: Thomas Tai <thomas.tai@oracle.com> Reviewed-by: Eric Saint-Etienne <eric.saint.etienne@oracle.com> Signed-off-by: Karl Volz <karl.volz@oracle.com> Reviewed-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: Jens Axboe <axboe@kernel.dk>
80 lines
2.0 KiB
C
80 lines
2.0 KiB
C
/*
|
|
* fault injection support for nvme.
|
|
*
|
|
* Copyright (c) 2018, Oracle and/or its affiliates
|
|
*
|
|
*/
|
|
|
|
#include <linux/moduleparam.h>
|
|
#include "nvme.h"
|
|
|
|
static DECLARE_FAULT_ATTR(fail_default_attr);
|
|
/* optional fault injection attributes boot time option:
|
|
* nvme_core.fail_request=<interval>,<probability>,<space>,<times>
|
|
*/
|
|
static char *fail_request;
|
|
module_param(fail_request, charp, 0000);
|
|
|
|
void nvme_fault_inject_init(struct nvme_ns *ns)
|
|
{
|
|
struct dentry *dir, *parent;
|
|
char *name = ns->disk->disk_name;
|
|
struct nvme_fault_inject *fault_inj = &ns->fault_inject;
|
|
struct fault_attr *attr = &fault_inj->attr;
|
|
|
|
/* set default fault injection attribute */
|
|
if (fail_request)
|
|
setup_fault_attr(&fail_default_attr, fail_request);
|
|
|
|
/* create debugfs directory and attribute */
|
|
parent = debugfs_create_dir(name, NULL);
|
|
if (!parent) {
|
|
pr_warn("%s: failed to create debugfs directory\n", name);
|
|
return;
|
|
}
|
|
|
|
*attr = fail_default_attr;
|
|
dir = fault_create_debugfs_attr("fault_inject", parent, attr);
|
|
if (IS_ERR(dir)) {
|
|
pr_warn("%s: failed to create debugfs attr\n", name);
|
|
debugfs_remove_recursive(parent);
|
|
return;
|
|
}
|
|
ns->fault_inject.parent = parent;
|
|
|
|
/* create debugfs for status code and dont_retry */
|
|
fault_inj->status = NVME_SC_INVALID_OPCODE;
|
|
fault_inj->dont_retry = true;
|
|
debugfs_create_x16("status", 0600, dir, &fault_inj->status);
|
|
debugfs_create_bool("dont_retry", 0600, dir, &fault_inj->dont_retry);
|
|
}
|
|
|
|
void nvme_fault_inject_fini(struct nvme_ns *ns)
|
|
{
|
|
/* remove debugfs directories */
|
|
debugfs_remove_recursive(ns->fault_inject.parent);
|
|
}
|
|
|
|
void nvme_should_fail(struct request *req)
|
|
{
|
|
struct gendisk *disk = req->rq_disk;
|
|
struct nvme_ns *ns = NULL;
|
|
u16 status;
|
|
|
|
/*
|
|
* make sure this request is coming from a valid namespace
|
|
*/
|
|
if (!disk)
|
|
return;
|
|
|
|
ns = disk->private_data;
|
|
if (ns && should_fail(&ns->fault_inject.attr, 1)) {
|
|
/* inject status code and DNR bit */
|
|
status = ns->fault_inject.status;
|
|
if (ns->fault_inject.dont_retry)
|
|
status |= NVME_SC_DNR;
|
|
nvme_req(req)->status = status;
|
|
}
|
|
}
|
|
EXPORT_SYMBOL_GPL(nvme_should_fail);
|