Luis Chamberlain
c032e65b07
blktrace: break out of blktrace setup on concurrent calls ...
[ Upstream commit 1b0b283648163dae2a214ca28ed5a99f62a77319 ]
We use one blktrace per request_queue, that means one per the entire
disk. So we cannot run one blktrace on say /dev/vda and then /dev/vda1,
or just two calls on /dev/vda.
We check for concurrent setup only at the very end of the blktrace setup though.
If we try to run two concurrent blktraces on the same block device the
second one will fail, and the first one seems to go on. However when
one tries to kill the first one one will see things like this:
The kernel will show these:
```
debugfs: File 'dropped' in directory 'nvme1n1' already present!
debugfs: File 'msg' in directory 'nvme1n1' already present!
debugfs: File 'trace0' in directory 'nvme1n1' already present!
``
And userspace just sees this error message for the second call:
```
blktrace /dev/nvme1n1
BLKTRACESETUP(2) /dev/nvme1n1 failed: 5/Input/output error
```
The first userspace process #1 will also claim that the files
were taken underneath their nose as well. The files are taken
away form the first process given that when the second blktrace
fails, it will follow up with a BLKTRACESTOP and BLKTRACETEARDOWN.
This means that even if go-happy process #1 is waiting for blktrace
data, we *have* been asked to take teardown the blktrace.
This can easily be reproduced with break-blktrace [0] run_0005.sh test.
Just break out early if we know we're already going to fail, this will
prevent trying to create the files all over again, which we know still
exist.
[0] https://github.com/mcgrof/break-blktrace
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-30 15:38:43 -04:00
bpf: Explicitly memset the bpf_attr structure
2020-04-02 17:20:40 +02:00
config: android: enable CONFIG_SECCOMP
2016-10-11 15:06:32 -07:00
kgdb: Prevent infinite recursive entries to the debugger
2020-06-20 10:24:14 +02:00
perf: Add cond_resched() to task_function_call()
2020-06-20 10:24:13 +02:00
kernel/gcov/fs.c: gcov_seq_next() should increase position index
2020-05-02 17:23:05 +02:00
genirq/generic_pending: Do not lose pending affinity update
2020-06-03 08:16:47 +02:00
livepatch/module: make TAINT_LIVEPATCH module-specific
2016-08-26 14:42:08 +02:00
locktorture: Print ratio of acquisitions, not failures
2020-04-24 07:59:15 +02:00
PM: hibernate: Freeze kernel threads in software_resume()
2020-05-05 19:14:36 +02:00
printk: fix integer overflow in setup_log_buf()
2019-11-28 18:28:15 +01:00
rcuperf: Fix cleanup path for invalid perf_type strings
2019-05-31 06:48:30 -07:00
sched/core: Fix PI boosting between RT and DEADLINE tasks
2020-06-30 15:38:43 -04:00
ptp: fix the race between the release of ptp_clock and cdev
2020-05-20 08:15:32 +02:00
blktrace: break out of blktrace setup on concurrent calls
2020-06-30 15:38:43 -04:00
kernel/acct.c: fix the acct->needcheck check in check_free_space()
2018-01-10 09:29:51 +01:00
kernel/async.c: revert "async: simplify lowest_in_progress()"
2018-02-17 13:21:18 +01:00
audit: check the length of userspace generated audit records
2020-05-02 17:23:12 +02:00
Merge branch 'stable-4.8' of git://git.infradead.org/users/pcmoore/audit
2016-07-29 17:54:17 -07:00
audit_get_nd(): don't unlock parent too early
2019-12-21 10:40:48 +01:00
audit: fix error handling in audit_data_to_entry()
2020-03-11 07:53:05 +01:00
audit: print empty EXECVE args
2019-11-28 18:28:55 +01:00
kbuild: fix kernel/bounds.c 'W=1' warning
2018-11-13 11:16:57 -08:00
ptrace: Capture the ptracer's creds not PT_PTRACE_CAP
2017-01-06 10:40:13 +01:00
cgroup: memcg: net: do not associate sock with unrelated cgroup
2020-03-20 09:07:43 +01:00
cgroup: pids: use atomic64_t for pids->limit
2019-12-21 10:42:02 +01:00
x86/speculation: Remove redundant arch_smt_update() invocation
2020-04-24 07:58:57 +02:00
kernel/cpu_pm: Fix uninitted local in cpu_pm
2020-06-20 10:24:21 +02:00
sched/cpuset/pm: Fix cpuset vs. suspend-resume bugs
2017-10-12 11:51:25 +02:00
memcg: account security cred as well to kmemcg
2020-01-12 11:24:13 +01:00
kernel/elfcore.c: include proper prototypes
2019-10-17 13:42:13 -07:00
exit: Move preemption fixup up, move blocking operations down
2020-06-20 10:24:16 +02:00
kernel/extable.c: mark core_kernel_text notrace
2017-07-21 07:42:21 +02:00
kernel/sysctl.c: do not override max_threads provided by userspace
2019-10-17 13:42:44 -07:00
freezer, oom: check TIF_MEMDIE on the correct task
2016-07-28 16:07:41 -07:00
futex: Unbreak futex hashing
2020-04-02 17:20:28 +02:00
kernel: make groups_sort calling a responsibility group_info allocators
2018-01-10 09:29:52 +01:00
kernel: hung_task.c: disable on suspend
2019-04-20 09:07:52 +02:00
jump_label: Invoke jump_label_test() via early_initcall()
2017-12-14 09:28:24 +01:00
kcov: ensure irq code sees a valid area
2018-08-03 07:55:12 +02:00
kexec: allow architectures to override boot mapping
2016-08-02 19:35:27 -04:00
objtool, x86: Add several functions and files to the objtool whitelist
2018-06-05 10:28:57 +02:00
kexec: fix double-free when failing to relocate the purgatory
2016-09-01 17:52:01 -07:00
kmod: make request_module() return an error when autoloading is disabled
2020-04-24 07:58:59 +02:00
kretprobe: Prevent triggering kretprobe from within kprobe_flush_task
2020-06-30 15:38:33 -04:00
kexec: add a kexec_crash_loaded() function
2016-08-02 19:35:30 -04:00
kthread, tracing: Don't expose half-written comm when creating kthreads
2018-08-03 07:55:12 +02:00
x86/uaccess, kcov: Disable stack protector
2019-06-22 08:17:19 +02:00
Fix: Disable sys_membarrier when nohz_full is enabled
2017-03-12 06:41:45 +01:00
mm, devm_memremap_pages: kill mapping "System RAM" support
2019-01-13 10:03:51 +01:00
kernel/module.c: wakeup processes in module_wq on module unload
2019-12-21 10:42:21 +01:00
x86/mm: split vmalloc_sync_all()
2020-04-02 17:20:26 +02:00
padata: purge get_cpu and reorder_via_wq from padata_do_serial
2020-05-27 16:41:53 +02:00
panic: ensure preemption is disabled during panic()
2019-10-17 13:42:25 -07:00
pidns: disable pid allocation if pid_ns_prepare_proc() is failed in alloc_pid()
2018-04-13 19:47:53 +02:00
signal/pid_namespace: Fix reboot_pid_ns to use send_sig not force_sig
2019-08-04 09:33:16 +02:00
profile: Convert to hotplug state machine
2016-07-15 10:41:42 +02:00
ptrace: Fix ->ptracer_cred handling for PTRACE_TRACEME
2019-07-10 09:55:45 +02:00
kernel/relay.c: handle alloc_percpu returning NULL in relay_open
2020-06-11 09:22:20 +02:00
resource: fix integer overflow at reallocation
2018-04-24 09:34:09 +02:00
seccomp: Move speculation migitation control to arch code
2018-05-22 16:58:02 +02:00
signal: Extend exec_id to 64bits
2020-04-24 07:58:54 +02:00
cpu/hotplug: Fix SMT supported evaluation
2018-08-15 18:14:53 +02:00
kthread/smpboot: do not park in kthread_create_on_cpu()
2016-10-11 15:06:33 -07:00
Mark HI and TASKLET softirq synchronous
2018-08-15 18:14:42 +02:00
stacktrace, lockdep: Fix address, newline ugliness
2017-02-14 15:25:42 -08:00
stop_machine: Use raw spinlocks
2018-08-03 07:55:24 +02:00
kernel/sys.c: prctl: fix false positive in validate_prctl_map()
2019-06-22 08:17:13 +02:00
x86/pkeys: Fix pkeys build breakage for some non-x86 arches
2016-09-13 14:41:36 +02:00
kernel: sysctl: make drop_caches write-only
2020-01-04 13:41:04 +01:00
task_work: use READ_ONCE/lockless_dereference, avoid pi_lock if !task_works
2016-08-02 19:35:02 -04:00
taskstats: fix data-race
2020-01-12 11:24:12 +01:00
torture: Convert torture_shutdown() to hrtimer
2016-08-22 10:01:49 -07:00
tracepoint: Do not warn on ENOMEM
2018-05-09 09:50:20 +02:00
kernel/ucount.c: mark user_header with kmemleak_ignore()
2017-06-17 06:41:51 +02:00
kernel: make groups_sort calling a responsibility group_info allocators
2018-01-10 09:29:52 +01:00
smp: Add function to execute a function synchronously on a CPU
2016-09-05 13:52:39 +02:00
userns: move user access out of the mutex
2018-09-09 20:01:24 +02:00
Merge branch 'nsfs-ioctls' into HEAD
2016-09-22 20:00:36 -05:00
sys: don't hold uts_sem while accessing userspace memory
2018-09-09 20:01:24 +02:00
kernel/watchdog: prevent false hardlockup on overloaded system
2017-06-17 06:41:57 +02:00
kernel/watchdog: prevent false hardlockup on overloaded system
2017-06-17 06:41:57 +02:00
workqueue: don't use wq_select_unbound_cpu() for bound works
2020-03-20 09:07:43 +01:00
workqueue: Fix NULL pointer dereference
2017-11-15 15:53:17 +01:00
c032e65b07