Commit Graph

768417 Commits

Author SHA1 Message Date
Len Brown
cfce494db3 tools/power turbostat: fix x2apic debug message output file
A recently added x2apic debug message was hard-coded to stderr.
That doesn't work with "-o outfile".

Signed-off-by: Len Brown <len.brown@intel.com>
2018-07-26 14:20:59 -04:00
Artem Bityutskiy
4f206a0fab tools/power turbostat: fix bogus summary values
This patch fixes a regression introduced in

commit 8cb48b32a5 ("tools/power turbostat: track thread ID in cpu_topology")

Turbostat uses incorrect cores number ('topo.num_cores') - its value is count
of logical CPUs, instead of count of physical cores. So it is twice as large as
it should be on a typical Intel system. For example, on a 6 core Xeon system
'topo.num_cores' is 12, and on a 52 core Xeon system 'topo.num_cores' is 104.

And interestingly, on a 68-core Knights Landing Intel system 'topo.num_cores'
is 272, because this system has 4 logical CPUs per core.

As a result, some of the turbostat calculations are incorrect. For example,
on idle 52-core Xeon system when all cores are ~99% in Core C6 (CPU%c6), the
summary (very first) line shows ~48% Core C6, while it should be ~99%.

This patch fixes the problem by fixing 'topo.num_cores' calculation.

Was:

1. Init 'thread_id' for all CPUs to -1
2. Run 'get_thread_siblings()' which sets it to 0 or 1
3. Increment 'topo.num_cores' when thread_id != -1 (bug!)

Now:

1. Init 'thread_id' for all CPUs to -1
2. Run 'get_thread_siblings()' which sets it to 0 or 1
3. Increment 'topo.num_cores' when thread_id is not 0

I did not have a chance to test this on an AMD machine, and only tested on a
couple of Intel Xeons (6 and 52 cores).

Reported-by: Vladislav Govtva <vladislav.govtva@intel.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2018-07-26 14:20:39 -04:00
Martin Wilck
17d51b10d7 block: bio_iov_iter_get_pages: pin more pages for multi-segment IOs
bio_iov_iter_get_pages() currently only adds pages for the next non-zero
segment from the iov_iter to the bio. That's suboptimal for callers,
which typically try to pin as many pages as fit into the bio. This patch
converts the current bio_iov_iter_get_pages() into a static helper, and
introduces a new helper that allocates as many pages as

 1) fit into the bio,
 2) are present in the iov_iter,
 3) and can be pinned by MM.

Error is returned only if zero pages could be pinned. Because of 3), a
zero return value doesn't necessarily mean all pages have been pinned.
Callers that have to pin every page in the iov_iter must still call this
function in a loop (this is currently the case).

This change matters most for __blkdev_direct_IO_simple(), which calls
bio_iov_iter_get_pages() only once. If it obtains less pages than
requested, it returns a "short write" or "short read", and
__generic_file_write_iter() falls back to buffered writes, which may
lead to data corruption.

Fixes: 72ecad22d9 ("block: support a full bio worth of IO for simplified bdev direct-io")
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin Wilck <mwilck@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-07-26 11:52:36 -06:00
Martin Wilck
9362dd1109 blkdev: __blkdev_direct_IO_simple: fix leak in error case
Fixes: 72ecad22d9 ("block: support a full bio worth of IO for simplified bdev direct-io")
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin Wilck <mwilck@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-07-26 11:52:33 -06:00
Martin Wilck
b403ea2404 block: bio_iov_iter_get_pages: fix size of last iovec
If the last page of the bio is not "full", the length of the last
vector slot needs to be corrected. This slot has the index
(bio->bi_vcnt - 1), but only in bio->bi_io_vec. In the "bv" helper
array, which is shifted by the value of bio->bi_vcnt at function
invocation, the correct index is (nr_pages - 1).

v2: improved readability following suggestions from Ming Lei.
v3: followed a formatting suggestion from Christoph Hellwig.

Fixes: 2cefe4dbaa ("block: add bio_iov_iter_get_pages()")
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin Wilck <mwilck@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-07-26 11:52:29 -06:00
Jens Axboe
78e18063a9 Merge branch 'nvme-4.18' of git://git.infradead.org/nvme into for-linus
Pull NVMe fixes from Christoph:

"Two small fixes each for the FC code and the target."

* 'nvme-4.18' of git://git.infradead.org/nvme:
  nvmet: only check for filebacking on -ENOTBLK
  nvmet: fixup crash on NULL device path
  nvme: if_ready checks to fail io to deleting controller
  nvmet-fc: fix target sgl list on large transfers
2018-07-26 11:48:44 -06:00
Thomas Tai
bd91b56cb3 PCI/AER: Work around use-after-free in pcie_do_fatal_recovery()
When an fatal error is received by a non-bridge device, the device is
removed, and pci_stop_and_remove_bus_device() deallocates the device
structure.  The freed device structure is used by subsequent code to send
uevents and print messages.

Hold a reference on the device until we're finished using it.  This is not
an ideal fix because pcie_do_fatal_recovery() should not use the device at
all after removing it, but that's too big a project for right now.

Fixes: 7e9084b367 ("PCI/AER: Handle ERR_FATAL with removal and re-enumeration of devices")
Signed-off-by: Thomas Tai <thomas.tai@oracle.com>
[bhelgaas: changelog, reduce get/put coverage]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-07-26 12:13:04 -05:00
tangpengpeng
7f3fc7ddf7 net: fix amd-xgbe flow-control issue
If we enable or disable xgbe flow-control by ethtool ,
it does't work.Because the parameter is not properly
assigned,so we need to adjust the assignment order
of the parameters.

Fixes: c1ce2f7736 ("amd-xgbe: Fix flow control setting logic")
Signed-off-by: tangpengpeng <tangpengpeng@higon.com>
Acked-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-26 09:29:59 -07:00
Linus Torvalds
cd3f77d74a USB fixes for 4.18-rc7
Here are a number of USB fixes and new device ids for 4.18-rc7.
 
 The largest number are a bunch of gadget driver fixes that got delayed
 in being submitted earlier due to vacation schedules, but nothing really
 huge is present in them.  There are some new device ids and some PHY
 driver fixes that were connected to some USB ones.  Full details are in
 the shortlog.
 
 All have been in linux-next for a while with no reported issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'usb-4.18-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb

Pull USB fixes from Greg KH:
 "Here are a number of USB fixes and new device ids for 4.18-rc7.

  The largest number are a bunch of gadget driver fixes that got delayed
  in being submitted earlier due to vacation schedules, but nothing
  really huge is present in them. There are some new device ids and some
  PHY driver fixes that were connected to some USB ones. Full details
  are in the shortlog.

  All have been in linux-next for a while with no reported issues"

* tag 'usb-4.18-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (28 commits)
  usb: core: handle hub C_PORT_OVER_CURRENT condition
  usb: xhci: Fix memory leak in xhci_endpoint_reset()
  usb: typec: tcpm: Fix sink PDO starting index for PPS APDO selection
  usb: gadget: f_fs: Only return delayed status when len is 0
  usb: gadget: f_uac2: fix endianness of 'struct cntrl_*_lay3'
  usb: dwc2: Fix inefficient copy of unaligned buffers
  usb: dwc2: Fix DMA alignment to start at allocated boundary
  usb: dwc3: rockchip: Fix PHY documentation links.
  tools: usb: ffs-test: Fix build on big endian systems
  usb: gadget: aspeed: Workaround memory ordering issue
  usb: dwc3: gadget: remove redundant variable maxpacket
  usb: dwc2: avoid NULL dereferences
  usb/phy: fix PPC64 build errors in phy-fsl-usb.c
  usb: dwc2: host: do not delay retries for CONTROL IN transfers
  usb: gadget: u_audio: protect stream runtime fields with stream spinlock
  usb: gadget: u_audio: remove cached period bytes value
  usb: gadget: u_audio: remove caching of stream buffer parameters
  usb: gadget: u_audio: update hw_ptr in iso_complete after data copied
  usb: gadget: u_audio: fix pcm/card naming in g_audio_setup()
  usb: gadget: f_uac2: fix error handling in afunc_bind (again)
  ...
2018-07-26 09:29:29 -07:00
Linus Torvalds
fd4f84faec staging driver fixes for 4.18-rc7
Here are 3 small staging driver fixes for 4.18-rc7.  One is a revert of
 an earlier patch that turned out to be incorrect, one is a fix for the
 speakup drivers, and the last a fix for the ks7010 driver to resolve a
 regression.
 
 All of these have been in linux-next for a while with no reported
 issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'staging-4.18-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging

Pull staging driver fixes from Greg KH:
 "Here are three small staging driver fixes for 4.18-rc7.

  One is a revert of an earlier patch that turned out to be incorrect,
  one is a fix for the speakup drivers, and the last a fix for the
  ks7010 driver to resolve a regression.

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'staging-4.18-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
  staging: speakup: fix wraparound in uaccess length check
  staging: ks7010: call 'hostif_mib_set_request_int' instead of 'hostif_mib_set_request_bool'
  Revert "staging:r8188eu: Use lib80211 to support TKIP"
2018-07-26 09:26:41 -07:00
Linus Torvalds
a5f9e5dab3 Driver core fixes for 4.18-rc7
This is a single driver core fix for 4.18-rc7.  It partially reverts a
 previous commit to resolve some reported issues.
 
 It has been in linux-next for a while now with no reported issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-4.18-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core fix from Greg KH:
 "This is a single driver core fix for 4.18-rc7. It partially reverts a
  previous commit to resolve some reported issues.

  It has been in linux-next for a while now with no reported issues"

* tag 'driver-core-4.18-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  driver core: Partially revert "driver core: correct device's shutdown order"
2018-07-26 09:25:03 -07:00
Linus Torvalds
9bd591839e ACPI fix for 4.18-rc7
Fix a recent ACPICA regression causing the AML parser to get confused
 and fail in some situations involving incorrect AML in an ACPI table
 (Erik Schmauss).
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Merge tag 'acpi-4.18-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull ACPI fix from Rafael Wysocki:
 "Fix a recent ACPICA regression causing the AML parser to get confused
  and fail in some situations involving incorrect AML in an ACPI table
  (Erik Schmauss)"

* tag 'acpi-4.18-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPICA: AML Parser: ignore dispatcher error status during table load
2018-07-26 09:23:17 -07:00
Linus Torvalds
99015e94f2 Power management fix for 4.18-rc7
Fix up the recently introduced cpufreq driver for Qualcomm Kryo
 processors by adding a terminating NULL entry to its table of
 device IDs (YueHaibing).
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Merge tag 'pm-4.18-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management fix from Rafael Wysocki:
 "Fix up the recently introduced cpufreq driver for Qualcomm Kryo
  processors by adding a terminating NULL entry to its table of device
  IDs (YueHaibing)"

* tag 'pm-4.18-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  cpufreq: qcom-kryo: add NULL entry to the end of_device_id array
2018-07-26 09:21:28 -07:00
Snild Dolkow
3e536e222f kthread, tracing: Don't expose half-written comm when creating kthreads
There is a window for racing when printing directly to task->comm,
allowing other threads to see a non-terminated string. The vsnprintf
function fills the buffer, counts the truncated chars, then finally
writes the \0 at the end.

	creator                     other
	vsnprintf:
	  fill (not terminated)
	  count the rest            trace_sched_waking(p):
	  ...                         memcpy(comm, p->comm, TASK_COMM_LEN)
	  write \0

The consequences depend on how 'other' uses the string. In our case,
it was copied into the tracing system's saved cmdlines, a buffer of
adjacent TASK_COMM_LEN-byte buffers (note the 'n' where 0 should be):

	crash-arm64> x/1024s savedcmd->saved_cmdlines | grep 'evenk'
	0xffffffd5b3818640:     "irq/497-pwr_evenkworker/u16:12"

...and a strcpy out of there would cause stack corruption:

	[224761.522292] Kernel panic - not syncing: stack-protector:
	    Kernel stack is corrupted in: ffffff9bf9783c78

	crash-arm64> kbt | grep 'comm\|trace_print_context'
	#6  0xffffff9bf9783c78 in trace_print_context+0x18c(+396)
	      comm (char [16]) =  "irq/497-pwr_even"

	crash-arm64> rd 0xffffffd4d0e17d14 8
	ffffffd4d0e17d14:  2f71726900000000 5f7277702d373934   ....irq/497-pwr_
	ffffffd4d0e17d24:  726f776b6e657665 3a3631752f72656b   evenkworker/u16:
	ffffffd4d0e17d34:  f9780248ff003231 cede60e0ffffff9b   12..H.x......`..
	ffffffd4d0e17d44:  cede60c8ffffffd4 00000fffffffffd4   .....`..........

The workaround in e09e28671 (use strlcpy in __trace_find_cmdline) was
likely needed because of this same bug.

Solved by vsnprintf:ing to a local buffer, then using set_task_comm().
This way, there won't be a window where comm is not terminated.

Link: http://lkml.kernel.org/r/20180726071539.188015-1-snild@sony.com

Cc: stable@vger.kernel.org
Fixes: bc0c38d139 ("ftrace: latency tracer infrastructure")
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Snild Dolkow <snild@sony.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-07-26 09:59:33 -04:00
Sean Young
92cab799bb media: bpf: ensure bpf program is freed on detach
Currently we are leaking bpf programs when they are detached from the
lirc device; the refcount never reaches zero.

Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2018-07-26 08:39:18 -04:00
Arjun Vynipadath
942a656f1f cxgb4: Added missing break in ndo_udp_tunnel_{add/del}
Break statements were missing for Geneve case in
ndo_udp_tunnel_{add/del}, thereby raw mac matchall
entries were not getting added.

Fixes: c746fc0e8b2d("cxgb4: add geneve offload support for T6")
Signed-off-by: Arjun Vynipadath <arjun@chelsio.com>
Signed-off-by: Ganesh Goudar <ganeshgr@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-25 22:38:49 -07:00
Jakub Kicinski
c259b4fb33 netdevsim: don't leak devlink resources
Devlink resources registered with devlink_resource_register() have
to be unregistered.

Fixes: 37923ed6b8 ("netdevsim: Add simple FIB resource controller via devlink")
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-25 22:33:39 -07:00
Steven Rostedt (VMware)
2519c1bbe3 tracing: Quiet gcc warning about maybe unused link variable
Commit 57ea2a34ad ("tracing/kprobes: Fix trace_probe flags on
enable_trace_kprobe() failure") added an if statement that depends on another
if statement that gcc doesn't see will initialize the "link" variable and
gives the warning:

 "warning: 'link' may be used uninitialized in this function"

It is really a false positive, but to quiet the warning, and also to make
sure that it never actually is used uninitialized, initialize the "link"
variable to NULL and add an if (!WARN_ON_ONCE(!link)) where the compiler
thinks it could be used uninitialized.

Cc: stable@vger.kernel.org
Fixes: 57ea2a34ad ("tracing/kprobes: Fix trace_probe flags on enable_trace_kprobe() failure")
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-07-25 22:33:50 -04:00
Steven Rostedt (VMware)
15cc78644d tracing: Fix possible double free in event_enable_trigger_func()
There was a case that triggered a double free in event_trigger_callback()
due to the called reg() function freeing the trigger_data and then it
getting freed again by the error return by the caller. The solution there
was to up the trigger_data ref count.

Code inspection found that event_enable_trigger_func() has the same issue,
but is not as easy to trigger (requires harder to trigger failures). It
needs to be solved slightly different as it needs more to clean up when the
reg() function fails.

Link: http://lkml.kernel.org/r/20180725124008.7008e586@gandalf.local.home

Cc: stable@vger.kernel.org
Fixes: 7862ad1846 ("tracing: Add 'enable_event' and 'disable_event' event trigger commands")
Reivewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-07-25 21:25:16 -04:00
Björn Töpel
d24458e43b xsk: fix poll/POLLIN premature returns
Polling for the ingress queues relies on reading the producer/consumer
pointers of the Rx queue.

Prior this commit, a cached consumer pointer could be used, instead of
the actual consumer pointer and therefore report POLLIN prematurely.

This patch makes sure that the non-cached consumer pointer is used
instead.

Reported-by: Qi Zhang <qi.z.zhang@intel.com>
Tested-by: Qi Zhang <qi.z.zhang@intel.com>
Fixes: c497176cb2 ("xsk: add Rx receive functions and poll support")
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-07-26 02:53:10 +02:00
Wang YanQing
9e4e5b5c86 bpf, x32: Fix regression caused by commit 24dea04767
Commit 24dea04767 ("bpf, x32: remove ld_abs/ld_ind")
removed the 4 /* Extra space for skb_copy_bits buffer */
from _STACK_SIZE, but it didn't fix the concerned code
in emit_prologue and emit_epilogue, and this error will
bring very strange kernel runtime errors. This patch
fixes it.

Fixes: 24dea04767 ("bpf, x32: remove ld_abs/ld_ind")
Reported-by: Meelis Roos <mroos@linux.ee>
Bisected-by: Meelis Roos <mroos@linux.ee>
Signed-off-by: Wang YanQing <udknight@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-07-26 02:51:12 +02:00
Wei Yongjun
b87bac1012 net: igmp: make function __ip_mc_inc_group() static
Fixes the following sparse warnings:

net/ipv4/igmp.c:1391:6: warning:
 symbol '__ip_mc_inc_group' was not declared. Should it be static?

Fixes: 6e2059b53f ("ipv4/igmp: init group mode as INCLUDE when join source group")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-25 16:36:57 -07:00
Lawrence Brakmo
9aee400061 tcp: ack immediately when a cwr packet arrives
We observed high 99 and 99.9% latencies when doing RPCs with DCTCP. The
problem is triggered when the last packet of a request arrives CE
marked. The reply will carry the ECE mark causing TCP to shrink its cwnd
to 1 (because there are no packets in flight). When the 1st packet of
the next request arrives, the ACK was sometimes delayed even though it
is CWR marked, adding up to 40ms to the RPC latency.

This patch insures that CWR marked data packets arriving will be acked
immediately.

Packetdrill script to reproduce the problem:

0.000 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3
0.000 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0
0.000 setsockopt(3, SOL_TCP, TCP_CONGESTION, "dctcp", 5) = 0
0.000 bind(3, ..., ...) = 0
0.000 listen(3, 1) = 0

0.100 < [ect0] SEW 0:0(0) win 32792 <mss 1000,sackOK,nop,nop,nop,wscale 7>
0.100 > SE. 0:0(0) ack 1 <mss 1460,nop,nop,sackOK,nop,wscale 8>
0.110 < [ect0] . 1:1(0) ack 1 win 257
0.200 accept(3, ..., ...) = 4

0.200 < [ect0] . 1:1001(1000) ack 1 win 257
0.200 > [ect01] . 1:1(0) ack 1001

0.200 write(4, ..., 1) = 1
0.200 > [ect01] P. 1:2(1) ack 1001

0.200 < [ect0] . 1001:2001(1000) ack 2 win 257
0.200 write(4, ..., 1) = 1
0.200 > [ect01] P. 2:3(1) ack 2001

0.200 < [ect0] . 2001:3001(1000) ack 3 win 257
0.200 < [ect0] . 3001:4001(1000) ack 3 win 257
0.200 > [ect01] . 3:3(0) ack 4001

0.210 < [ce] P. 4001:4501(500) ack 3 win 257

+0.001 read(4, ..., 4500) = 4500
+0 write(4, ..., 1) = 1
+0 > [ect01] PE. 3:4(1) ack 4501

+0.010 < [ect0] W. 4501:5501(1000) ack 4 win 257
// Previously the ACK sequence below would be 4501, causing a long RTO
+0.040~+0.045 > [ect01] . 4:4(0) ack 5501   // delayed ack

+0.311 < [ect0] . 5501:6501(1000) ack 4 win 257  // More data
+0 > [ect01] . 4:4(0) ack 6501     // now acks everything

+0.500 < F. 9501:9501(0) ack 4 win 257

Modified based on comments by Neal Cardwell <ncardwell@google.com>

Signed-off-by: Lawrence Brakmo <brakmo@fb.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-25 16:20:35 -07:00
Clint Taylor
0ca9488193 drm/i915/glk: Add Quirk for GLK NUC HDMI port issues.
On GLK NUC platforms the HDMI retiming buffer needs additional disabled
time to correctly sync to a faster incoming signal.

When measured on a scope the highspeed lines of the HDMI clock turn off
 for ~400uS during a normal resolution change. The HDMI retimer on the
 GLK NUC appears to require at least a full frame of quiet time before a
new faster clock can be correctly sync'd. Wait 100ms due to msleep
inaccuracies while waiting for a completed frame. Add a quirk to the
driver for GLK boards that use ITE66317 HDMI retimers.

V2: Add more devices to the quirk list
V3: Delay increased to 100ms, check to confirm crtc type is HDMI.
V4: crtc type check extended to include _DDI and whitespace fixes
v5: Fix white spaces, remove the macro for delay. Revert the crtc type
    check introduced in v4.

Cc: Imre Deak <imre.deak@intel.com>
Cc: <stable@vger.kernel.org> # v4.14+
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=105887
Signed-off-by: Clint Taylor <clinton.a.taylor@intel.com>
Tested-by: Daniel Scheller <d.scheller.oss@gmail.com>
Signed-off-by: Radhakrishna Sripada <radhakrishna.sripada@intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180710200205.1478-1-radhakrishna.sripada@intel.com
(cherry picked from commit 90c3e21987)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
2018-07-25 14:52:17 -07:00
dann frazier
7856e86162 hinic: Link the logical network device to the pci device in sysfs
Otherwise interfaces get exposed under /sys/devices/virtual, which
doesn't give udev the context it needs for PCI-based predictable
interface names.

Signed-off-by: dann frazier <dann.frazier@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-25 13:54:52 -07:00
Toshiaki Makita
ecbc42ca5d virtio_net: Fix incosistent received bytes counter
When received packets are dropped in virtio_net driver, received packets
counter is incremented but bytes counter is not.
As a result, for instance if we drop all packets by XDP, only received
is counted and bytes stays 0, which looks inconsistent.
IMHO received packets/bytes should be counted if packets are produced by
the hypervisor, like what common NICs on physical machines are doing.
So fix the bytes counter.

Signed-off-by: Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-25 12:58:25 -07:00
Linus Torvalds
6e77b26772 One more round of updates for problems seen this -rc series. Drivers fixes
are:
 
  - Amlogic Meson audio divider fix and CPU clk critical marking
 
  - Qualcomm multimedia GDSC marked as 'always on' to keep display working
 
  - Aspeed fixes for critical clks, resets causing clks to stay disabled, and
    an incorrect HPLL frequency calculation
 
  - Marvell Armada 3700 cpu clks would undervolt when switching from low
    frequencies to high frequencies because the voltage didn't stabilize in
    time so now we switch to an intermediate frequency
 
 Plus we have a core framework thinko that messed up the debugfs flag
 printing logic to make it not very useful.
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Merge tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux

Pull clk fixes from Stephen Boyd:
 "One more round of updates for problems seen this -rc series. Drivers
  fixes are:

   - Amlogic Meson audio divider fix and CPU clk critical marking

   - Qualcomm multimedia GDSC marked as 'always on' to keep display
     working

   - Aspeed fixes for critical clks, resets causing clks to stay
     disabled, and an incorrect HPLL frequency calculation

   - Marvell Armada 3700 cpu clks would undervolt when switching from
     low frequencies to high frequencies because the voltage didn't
     stabilize in time so now we switch to an intermediate frequency

  Plus we have a core framework thinko that messed up the debugfs flag
  printing logic to make it not very useful"

* tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux:
  clk: aspeed: Support HPLL strapping on ast2400
  clk: mvebu: armada-37xx-periph: Fix switching CPU rate from 300Mhz to 1.2GHz
  clk: aspeed: Mark bclk (PCIe) and dclk (VGA) as critical
  clk/mmcc-msm8996: Make mmagic_bimc_gdsc ALWAYS_ON
  clk: aspeed: Treat a gate in reset as disabled
  clk: Really show symbolic clock flags in debugfs
  clk: qcom: gcc-msm8996: Disable halt check on UFS tx clock
  clk: meson: audio-divider is one based
  clk: meson-gxbb: set fclk_div2 as CLK_IS_CRITICAL
2018-07-25 11:03:56 -07:00
Linus Torvalds
5c61ef1b7c fscache fixes
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Merge tag 'fscache-fixes-20180725' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

Pull fscache/cachefiles fixes from David Howells:

 - Allow cancelled operations to be queued so they can be cleaned up.

 - Fix a refcounting bug in the monitoring of reads on backend files
   whereby a race can occur between monitor objects being listed for
   work, the work processing being queued and the work processor running
   and destroying the monitor objects.

 - Fix a ref overput in object attachment, whereby a tentatively
   considered object is put in error handling without first being 'got'.

 - Fix a missing clear of the CACHEFILES_OBJECT_ACTIVE flag whereby an
   assertion occurs when we retry because it seems the object is now
   active.

 - Wait rather BUG'ing on an object collision in the depths of
   cachefiles as the active object should be being cleaned up - also
   depends on the one above.

* tag 'fscache-fixes-20180725' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
  cachefiles: Wait rather than BUG'ing on "Unexpected object collision"
  cachefiles: Fix missing clear of the CACHEFILES_OBJECT_ACTIVE flag
  fscache: Fix reference overput in fscache_attach_object() error handling
  cachefiles: Fix refcounting bug in backing-file read monitoring
  fscache: Allow cancelled operations to be enqueued
2018-07-25 10:55:24 -07:00
Artem Savkov
57ea2a34ad tracing/kprobes: Fix trace_probe flags on enable_trace_kprobe() failure
If enable_trace_kprobe fails to enable the probe in enable_k(ret)probe
it returns an error, but does not unset the tp flags it set previously.
This results in a probe being considered enabled and failures like being
unable to remove the probe through kprobe_events file since probes_open()
expects every probe to be disabled.

Link: http://lkml.kernel.org/r/20180725102826.8300-1-asavkov@redhat.com
Link: http://lkml.kernel.org/r/20180725142038.4765-1-asavkov@redhat.com

Cc: Ingo Molnar <mingo@redhat.com>
Cc: stable@vger.kernel.org
Fixes: 41a7dd420c ("tracing/kprobes: Support ftrace_event_file base multibuffer")
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Artem Savkov <asavkov@redhat.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-07-25 11:41:08 -04:00
Masami Hiramatsu
82f4f3e69c selftests/ftrace: Add snapshot and tracing_on test case
Add a testcase for checking snapshot and tracing_on
relationship. This ensures that the snapshotting doesn't
affect current tracing on/off settings.

Link: http://lkml.kernel.org/r/153149932412.11274.15289227592627901488.stgit@devbox

Cc: Tom Zanussi <tom.zanussi@linux.intel.com>
Cc: Hiraku Toyooka <hiraku.toyooka@cybertrust.co.jp>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: linux-kselftest@vger.kernel.org
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-07-25 10:29:42 -04:00
Masami Hiramatsu
73c8d89455 ring_buffer: tracing: Inherit the tracing setting to next ring buffer
Maintain the tracing on/off setting of the ring_buffer when switching
to the trace buffer snapshot.

Taking a snapshot is done by swapping the backup ring buffer
(max_tr_buffer). But since the tracing on/off setting is defined
by the ring buffer, when swapping it, the tracing on/off setting
can also be changed. This causes a strange result like below:

  /sys/kernel/debug/tracing # cat tracing_on
  1
  /sys/kernel/debug/tracing # echo 0 > tracing_on
  /sys/kernel/debug/tracing # cat tracing_on
  0
  /sys/kernel/debug/tracing # echo 1 > snapshot
  /sys/kernel/debug/tracing # cat tracing_on
  1
  /sys/kernel/debug/tracing # echo 1 > snapshot
  /sys/kernel/debug/tracing # cat tracing_on
  0

We don't touch tracing_on, but snapshot changes tracing_on
setting each time. This is an anomaly, because user doesn't know
that each "ring_buffer" stores its own tracing-enable state and
the snapshot is done by swapping ring buffers.

Link: http://lkml.kernel.org/r/153149929558.11274.11730609978254724394.stgit@devbox

Cc: Ingo Molnar <mingo@redhat.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Tom Zanussi <tom.zanussi@linux.intel.com>
Cc: Hiraku Toyooka <hiraku.toyooka@cybertrust.co.jp>
Cc: stable@vger.kernel.org
Fixes: debdd57f51 ("tracing: Make a snapshot feature available from userspace")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
[ Updated commit log and comment in the code ]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-07-25 10:29:41 -04:00
Steven Rostedt (VMware)
1863c38725 tracing: Fix double free of event_trigger_data
Running the following:

 # cd /sys/kernel/debug/tracing
 # echo 500000 > buffer_size_kb
[ Or some other number that takes up most of memory ]
 # echo snapshot > events/sched/sched_switch/trigger

Triggers the following bug:

 ------------[ cut here ]------------
 kernel BUG at mm/slub.c:296!
 invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC PTI
 CPU: 6 PID: 6878 Comm: bash Not tainted 4.18.0-rc6-test+ #1066
 Hardware name: Hewlett-Packard HP Compaq Pro 6300 SFF/339A, BIOS K01 v03.03 07/14/2016
 RIP: 0010:kfree+0x16c/0x180
 Code: 05 41 0f b6 72 51 5b 5d 41 5c 4c 89 d7 e9 ac b3 f8 ff 48 89 d9 48 89 da 41 b8 01 00 00 00 5b 5d 41 5c 4c 89 d6 e9 f4 f3 ff ff <0f> 0b 0f 0b 48 8b 3d d9 d8 f9 00 e9 c1 fe ff ff 0f 1f 40 00 0f 1f
 RSP: 0018:ffffb654436d3d88 EFLAGS: 00010246
 RAX: ffff91a9d50f3d80 RBX: ffff91a9d50f3d80 RCX: ffff91a9d50f3d80
 RDX: 00000000000006a4 RSI: ffff91a9de5a60e0 RDI: ffff91a9d9803500
 RBP: ffffffff8d267c80 R08: 00000000000260e0 R09: ffffffff8c1a56be
 R10: fffff0d404543cc0 R11: 0000000000000389 R12: ffffffff8c1a56be
 R13: ffff91a9d9930e18 R14: ffff91a98c0c2890 R15: ffffffff8d267d00
 FS:  00007f363ea64700(0000) GS:ffff91a9de580000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 000055c1cacc8e10 CR3: 00000000d9b46003 CR4: 00000000001606e0
 Call Trace:
  event_trigger_callback+0xee/0x1d0
  event_trigger_write+0xfc/0x1a0
  __vfs_write+0x33/0x190
  ? handle_mm_fault+0x115/0x230
  ? _cond_resched+0x16/0x40
  vfs_write+0xb0/0x190
  ksys_write+0x52/0xc0
  do_syscall_64+0x5a/0x160
  entry_SYSCALL_64_after_hwframe+0x49/0xbe
 RIP: 0033:0x7f363e16ab50
 Code: 73 01 c3 48 8b 0d 38 83 2c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 79 db 2c 00 00 75 10 b8 01 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 1e e3 01 00 48 89 04 24
 RSP: 002b:00007fff9a4c6378 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
 RAX: ffffffffffffffda RBX: 0000000000000009 RCX: 00007f363e16ab50
 RDX: 0000000000000009 RSI: 000055c1cacc8e10 RDI: 0000000000000001
 RBP: 000055c1cacc8e10 R08: 00007f363e435740 R09: 00007f363ea64700
 R10: 0000000000000073 R11: 0000000000000246 R12: 0000000000000009
 R13: 0000000000000001 R14: 00007f363e4345e0 R15: 00007f363e4303c0
 Modules linked in: ip6table_filter ip6_tables snd_hda_codec_hdmi snd_hda_codec_realtek snd_hda_codec_generic snd_hda_intel snd_hda_codec snd_hwdep snd_hda_core snd_seq snd_seq_device i915 snd_pcm snd_timer i2c_i801 snd soundcore i2c_algo_bit drm_kms_helper
86_pkg_temp_thermal video kvm_intel kvm irqbypass wmi e1000e
 ---[ end trace d301afa879ddfa25 ]---

The cause is because the register_snapshot_trigger() call failed to
allocate the snapshot buffer, and then called unregister_trigger()
which freed the data that was passed to it. Then on return to the
function that called register_snapshot_trigger(), as it sees it
failed to register, it frees the trigger_data again and causes
a double free.

By calling event_trigger_init() on the trigger_data (which only ups
the reference counter for it), and then event_trigger_free() afterward,
the trigger_data would not get freed by the registering trigger function
as it would only up and lower the ref count for it. If the register
trigger function fails, then the event_trigger_free() called after it
will free the trigger data normally.

Link: http://lkml.kernel.org/r/20180724191331.738eb819@gandalf.local.home

Cc: stable@vger.kerne.org
Fixes: 93e31ffbf4 ("tracing: Add 'snapshot' event trigger command")
Reported-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-07-25 10:29:24 -04:00
Kiran Kumar Modukuri
c2412ac45a cachefiles: Wait rather than BUG'ing on "Unexpected object collision"
If we meet a conflicting object that is marked FSCACHE_OBJECT_IS_LIVE in
the active object tree, we have been emitting a BUG after logging
information about it and the new object.

Instead, we should wait for the CACHEFILES_OBJECT_ACTIVE flag to be cleared
on the old object (or return an error).  The ACTIVE flag should be cleared
after it has been removed from the active object tree.  A timeout of 60s is
used in the wait, so we shouldn't be able to get stuck there.

Fixes: 9ae326a690 ("CacheFiles: A cache that backs onto a mounted filesystem")
Signed-off-by: Kiran Kumar Modukuri <kiran.modukuri@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2018-07-25 14:49:00 +01:00
Kiran Kumar Modukuri
5ce83d4bb7 cachefiles: Fix missing clear of the CACHEFILES_OBJECT_ACTIVE flag
In cachefiles_mark_object_active(), the new object is marked active and
then we try to add it to the active object tree.  If a conflicting object
is already present, we want to wait for that to go away.  After the wait,
we go round again and try to re-mark the object as being active - but it's
already marked active from the first time we went through and a BUG is
issued.

Fix this by clearing the CACHEFILES_OBJECT_ACTIVE flag before we try again.

Analysis from Kiran Kumar Modukuri:

[Impact]
Oops during heavy NFS + FSCache + Cachefiles

CacheFiles: Error: Overlong wait for old active object to go away.

BUG: unable to handle kernel NULL pointer dereference at 0000000000000002

CacheFiles: Error: Object already active kernel BUG at
fs/cachefiles/namei.c:163!

[Cause]
In a heavily loaded system with big files being read and truncated, an
fscache object for a cookie is being dropped and a new object being
looked. The new object being looked for has to wait for the old object
to go away before the new object is moved to active state.

[Fix]
Clear the flag 'CACHEFILES_OBJECT_ACTIVE' for the new object when
retrying the object lookup.

[Testcase]
Have run ~100 hours of NFS stress tests and have not seen this bug recur.

[Regression Potential]
 - Limited to fscache/cachefiles.

Fixes: 9ae326a690 ("CacheFiles: A cache that backs onto a mounted filesystem")
Signed-off-by: Kiran Kumar Modukuri <kiran.modukuri@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2018-07-25 14:49:00 +01:00
Kiran Kumar Modukuri
f29507ce66 fscache: Fix reference overput in fscache_attach_object() error handling
When a cookie is allocated that causes fscache_object structs to be
allocated, those objects are initialised with the cookie pointer, but
aren't blessed with a ref on that cookie unless the attachment is
successfully completed in fscache_attach_object().

If attachment fails because the parent object was dying or there was a
collision, fscache_attach_object() returns without incrementing the cookie
counter - but upon failure of this function, the object is released which
then puts the cookie, whether or not a ref was taken on the cookie.

Fix this by taking a ref on the cookie when it is assigned in
fscache_object_init(), even when we're creating a root object.


Analysis from Kiran Kumar:

This bug has been seen in 4.4.0-124-generic #148-Ubuntu kernel

BugLink: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1776277

fscache cookie ref count updated incorrectly during fscache object
allocation resulting in following Oops.

kernel BUG at /build/linux-Y09MKI/linux-4.4.0/fs/fscache/internal.h:321!
kernel BUG at /build/linux-Y09MKI/linux-4.4.0/fs/fscache/cookie.c:639!

[Cause]
Two threads are trying to do operate on a cookie and two objects.

(1) One thread tries to unmount the filesystem and in process goes over a
    huge list of objects marking them dead and deleting the objects.
    cookie->usage is also decremented in following path:

      nfs_fscache_release_super_cookie
       -> __fscache_relinquish_cookie
        ->__fscache_cookie_put
        ->BUG_ON(atomic_read(&cookie->usage) <= 0);

(2) A second thread tries to lookup an object for reading data in following
    path:

    fscache_alloc_object
    1) cachefiles_alloc_object
        -> fscache_object_init
           -> assign cookie, but usage not bumped.
    2) fscache_attach_object -> fails in cant_attach_object because the
         cookie's backing object or cookie's->parent object are going away
    3) fscache_put_object
        -> cachefiles_put_object
          ->fscache_object_destroy
            ->fscache_cookie_put
               ->BUG_ON(atomic_read(&cookie->usage) <= 0);

[NOTE from dhowells] It's unclear as to the circumstances in which (2) can
take place, given that thread (1) is in nfs_kill_super(), however a
conflicting NFS mount with slightly different parameters that creates a
different superblock would do it.  A backtrace from Kiran seems to show
that this is a possibility:

    kernel BUG at/build/linux-Y09MKI/linux-4.4.0/fs/fscache/cookie.c:639!
    ...
    RIP: __fscache_cookie_put+0x3a/0x40 [fscache]
    Call Trace:
     __fscache_relinquish_cookie+0x87/0x120 [fscache]
     nfs_fscache_release_super_cookie+0x2d/0xb0 [nfs]
     nfs_kill_super+0x29/0x40 [nfs]
     deactivate_locked_super+0x48/0x80
     deactivate_super+0x5c/0x60
     cleanup_mnt+0x3f/0x90
     __cleanup_mnt+0x12/0x20
     task_work_run+0x86/0xb0
     exit_to_usermode_loop+0xc2/0xd0
     syscall_return_slowpath+0x4e/0x60
     int_ret_from_sys_call+0x25/0x9f

[Fix] Bump up the cookie usage in fscache_object_init, when it is first
being assigned a cookie atomically such that the cookie is added and bumped
up if its refcount is not zero.  Remove the assignment in
fscache_attach_object().

[Testcase]
I have run ~100 hours of NFS stress tests and not seen this bug recur.

[Regression Potential]
 - Limited to fscache/cachefiles.

Fixes: ccc4fc3d11 ("FS-Cache: Implement the cookie management part of the netfs API")
Signed-off-by: Kiran Kumar Modukuri <kiran.modukuri@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2018-07-25 14:49:00 +01:00
Kiran Kumar Modukuri
934140ab02 cachefiles: Fix refcounting bug in backing-file read monitoring
cachefiles_read_waiter() has the right to access a 'monitor' object by
virtue of being called under the waitqueue lock for one of the pages in its
purview.  However, it has no ref on that monitor object or on the
associated operation.

What it is allowed to do is to move the monitor object to the operation's
to_do list, but once it drops the work_lock, it's actually no longer
permitted to access that object.  However, it is trying to enqueue the
retrieval operation for processing - but it can only do this via a pointer
in the monitor object, something it shouldn't be doing.

If it doesn't enqueue the operation, the operation may not get processed.
If the order is flipped so that the enqueue is first, then it's possible
for the work processor to look at the to_do list before the monitor is
enqueued upon it.

Fix this by getting a ref on the operation so that we can trust that it
will still be there once we've added the monitor to the to_do list and
dropped the work_lock.  The op can then be enqueued after the lock is
dropped.

The bug can manifest in one of a couple of ways.  The first manifestation
looks like:

 FS-Cache:
 FS-Cache: Assertion failed
 FS-Cache: 6 == 5 is false
 ------------[ cut here ]------------
 kernel BUG at fs/fscache/operation.c:494!
 RIP: 0010:fscache_put_operation+0x1e3/0x1f0
 ...
 fscache_op_work_func+0x26/0x50
 process_one_work+0x131/0x290
 worker_thread+0x45/0x360
 kthread+0xf8/0x130
 ? create_worker+0x190/0x190
 ? kthread_cancel_work_sync+0x10/0x10
 ret_from_fork+0x1f/0x30

This is due to the operation being in the DEAD state (6) rather than
INITIALISED, COMPLETE or CANCELLED (5) because it's already passed through
fscache_put_operation().

The bug can also manifest like the following:

 kernel BUG at fs/fscache/operation.c:69!
 ...
    [exception RIP: fscache_enqueue_operation+246]
 ...
 #7 [ffff883fff083c10] fscache_enqueue_operation at ffffffffa0b793c6
 #8 [ffff883fff083c28] cachefiles_read_waiter at ffffffffa0b15a48
 #9 [ffff883fff083c48] __wake_up_common at ffffffff810af028

I'm not entirely certain as to which is line 69 in Lei's kernel, so I'm not
entirely clear which assertion failed.

Fixes: 9ae326a690 ("CacheFiles: A cache that backs onto a mounted filesystem")
Reported-by: Lei Xue <carmark.dlut@gmail.com>
Reported-by: Vegard Nossum <vegard.nossum@gmail.com>
Reported-by: Anthony DeRobertis <aderobertis@metrics.net>
Reported-by: NeilBrown <neilb@suse.com>
Reported-by: Daniel Axtens <dja@axtens.net>
Reported-by: Kiran Kumar Modukuri <kiran.modukuri@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Daniel Axtens <dja@axtens.net>
2018-07-25 14:49:00 +01:00
Kiran Kumar Modukuri
d0eb06afe7 fscache: Allow cancelled operations to be enqueued
Alter the state-check assertion in fscache_enqueue_operation() to allow
cancelled operations to be given processing time so they can be cleaned up.

Also fix a debugging statement that was requiring such operations to have
an object assigned.

Fixes: 9ae326a690 ("CacheFiles: A cache that backs onto a mounted filesystem")
Reported-by: Kiran Kumar Modukuri <kiran.modukuri@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2018-07-25 14:31:20 +01:00
Johannes Weiner
7b0eb6b41a arm64: fix vmemmap BUILD_BUG_ON() triggering on !vmemmap setups
Arnd reports the following arm64 randconfig build error with the PSI
patches that add another page flag:

  /git/arm-soc/arch/arm64/mm/init.c: In function 'mem_init':
  /git/arm-soc/include/linux/compiler.h:357:38: error: call to
  '__compiletime_assert_618' declared with attribute error: BUILD_BUG_ON
  failed: sizeof(struct page) > (1 << STRUCT_PAGE_MAX_SHIFT)

The additional page flag causes other information stored in
page->flags to get bumped into their own struct page member:

  #if SECTIONS_WIDTH+ZONES_WIDTH+NODES_SHIFT+LAST_CPUPID_SHIFT <=
  BITS_PER_LONG - NR_PAGEFLAGS
  #define LAST_CPUPID_WIDTH LAST_CPUPID_SHIFT
  #else
  #define LAST_CPUPID_WIDTH 0
  #endif

  #if defined(CONFIG_NUMA_BALANCING) && LAST_CPUPID_WIDTH == 0
  #define LAST_CPUPID_NOT_IN_PAGE_FLAGS
  #endif

which in turn causes the struct page size to exceed the size set in
STRUCT_PAGE_MAX_SHIFT. This value is an an estimate used to size the
VMEMMAP page array according to address space and struct page size.

However, the check is performed - and triggers here - on a !VMEMMAP
config, which consumes an additional 22 page bits for the sparse
section id. When VMEMMAP is enabled, those bits are returned, cpupid
doesn't need its own member, and the page passes the VMEMMAP check.

Restrict that check to the situation it was meant to check: that we
are sizing the VMEMMAP page array correctly.

Says Arnd:

    Further experiments show that the build error already existed before,
    but was only triggered with larger values of CONFIG_NR_CPU and/or
    CONFIG_NODES_SHIFT that might be used in actual configurations but
    not in randconfig builds.

    With longer CPU and node masks, I could recreate the problem with
    kernels as old as linux-4.7 when arm64 NUMA support got added.

Reported-by: Arnd Bergmann <arnd@arndb.de>
Tested-by: Arnd Bergmann <arnd@arndb.de>
Cc: stable@vger.kernel.org
Fixes: 1a2db30034 ("arm64, numa: Add NUMA support for arm64 platforms.")
Fixes: 3e1907d5bf ("arm64: mm: move vmemmap region right below the linear region")
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-07-25 13:32:30 +01:00
Dirk Mueller
dc0e36581e arm64: Check for errata before evaluating cpu features
Since commit d3aec8a28b ("arm64: capabilities: Restrict KPTI
detection to boot-time CPUs") we rely on errata flags being already
populated during feature enumeration. The order of errata and
features was flipped as part of commit ed478b3f9e ("arm64:
capabilities: Group handling of features and errata workarounds").

Return to the orginal order of errata and feature evaluation to
ensure errata flags are present during feature evaluation.

Fixes: ed478b3f9e ("arm64: capabilities: Group handling of
    features and errata workarounds")
CC: Suzuki K Poulose <suzuki.poulose@arm.com>
CC: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Dirk Mueller <dmueller@suse.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-07-25 13:30:04 +01:00
Hannes Reinecke
405a751960 nvmet: only check for filebacking on -ENOTBLK
We only need to check for a file-backed namespace if
nvmet_bdev_ns_enable() returns -ENOTBLK. For any other error
it's pointless as the open() error will remain the same.

Fixes: d5eff33e ("nvmet: add simple file backed ns support")
Signed-off-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-07-25 13:14:04 +02:00
Hannes Reinecke
5613d31214 nvmet: fixup crash on NULL device path
When writing an empty string into the device_path attribute the kernel
will crash with

nvmet: failed to open block device (null): (-22)
BUG: unable to handle kernel NULL pointer dereference at 0000000000000000

This patch sanitizes the error handling for invalid device path settings.

Fixes: a07b4970 ("nvmet: add a generic NVMe target")
Signed-off-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-07-25 13:14:03 +02:00
Kees Cook
92a4728608 x86/boot: Fix if_changed build flip/flop bug
Dirk Gouders reported that two consecutive "make" invocations on an
already compiled tree will show alternating behaviors:

$ make
  CALL    scripts/checksyscalls.sh
  DESCEND  objtool
  CHK     include/generated/compile.h
  DATAREL arch/x86/boot/compressed/vmlinux
Kernel: arch/x86/boot/bzImage is ready  (#48)
  Building modules, stage 2.
  MODPOST 165 modules

$ make
  CALL    scripts/checksyscalls.sh
  DESCEND  objtool
  CHK     include/generated/compile.h
  LD      arch/x86/boot/compressed/vmlinux
  ZOFFSET arch/x86/boot/zoffset.h
  AS      arch/x86/boot/header.o
  LD      arch/x86/boot/setup.elf
  OBJCOPY arch/x86/boot/setup.bin
  OBJCOPY arch/x86/boot/vmlinux.bin
  BUILD   arch/x86/boot/bzImage
Setup is 15644 bytes (padded to 15872 bytes).
System is 6663 kB
CRC 3eb90f40
Kernel: arch/x86/boot/bzImage is ready  (#48)
  Building modules, stage 2.
  MODPOST 165 modules

He bisected it back to:

    commit 98f7852537 ("x86/boot: Refuse to build with data relocations")

The root cause was the use of the "if_changed" kbuild function multiple
times for the same target. It was designed to only be used once per
target, otherwise it will effectively always trigger, flipping back and
forth between the two commands getting recorded by "if_changed". Instead,
this patch merges the two commands into a single function to get stable
build artifacts (i.e. .vmlinux.cmd), and a single build behavior.

Bisected-and-Reported-by: Dirk Gouders <dirk@gouders.net>
Fix-Suggested-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20180724230827.GA37823@beast
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-25 12:00:08 +02:00
Mathieu Poirier
7f635ff187 perf/core: Fix crash when using HW tracing kernel filters
In function perf_event_parse_addr_filter(), the path::dentry of each struct
perf_addr_filter is left unassigned (as it should be) when the pattern
being parsed is related to kernel space.  But in function
perf_addr_filter_match() the same dentries are given to d_inode() where
the value is not expected to be NULL, resulting in the following splat:

  Unable to handle kernel NULL pointer dereference at virtual address 0000000000000058
  pc : perf_event_mmap+0x2fc/0x5a0
  lr : perf_event_mmap+0x2c8/0x5a0
  Process uname (pid: 2860, stack limit = 0x000000001cbcca37)
  Call trace:
   perf_event_mmap+0x2fc/0x5a0
   mmap_region+0x124/0x570
   do_mmap+0x344/0x4f8
   vm_mmap_pgoff+0xe4/0x110
   vm_mmap+0x2c/0x40
   elf_map+0x60/0x108
   load_elf_binary+0x450/0x12c4
   search_binary_handler+0x90/0x290
   __do_execve_file.isra.13+0x6e4/0x858
   sys_execve+0x3c/0x50
   el0_svc_naked+0x30/0x34

This patch is fixing the problem by introducing a new check in function
perf_addr_filter_match() to see if the filter's dentry is NULL.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: acme@kernel.org
Cc: miklos@szeredi.hu
Cc: namhyung@kernel.org
Cc: songliubraving@fb.com
Fixes: 9511bce9fe ("perf/core: Fix bad use of igrab()")
Link: http://lkml.kernel.org/r/1531782831-1186-1-git-send-email-mathieu.poirier@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-25 11:46:22 +02:00
Peter Zijlstra
6cbc304f2f perf/x86/intel: Fix unwind errors from PEBS entries (mk-II)
Vince reported the perf_fuzzer giving various unwinder warnings and
Josh reported:

> Deja vu.  Most of these are related to perf PEBS, similar to the
> following issue:
>
>   b8000586c9 ("perf/x86/intel: Cure bogus unwind from PEBS entries")
>
> This is basically the ORC version of that.  setup_pebs_sample_data() is
> assembling a franken-pt_regs which ORC isn't happy about.  RIP is
> inconsistent with some of the other registers (like RSP and RBP).

And where the previous unwinder only needed BP,SP ORC also requires
IP. But we cannot spoof IP because then the sample will get displaced,
entirely negating the point of PEBS.

So cure the whole thing differently by doing the unwind early; this
does however require a means to communicate we did the unwind early.
We (ab)use an unused sample_type bit for this, which we set on events
that fill out the data->callchain before the normal
perf_prepare_sample().

Debugged-by: Josh Poimboeuf <jpoimboe@redhat.com>
Reported-by: Vince Weaver <vincent.weaver@maine.edu>
Tested-by: Josh Poimboeuf <jpoimboe@redhat.com>
Tested-by: Prashant Bhole <bhole_prashant_q7@lab.ntt.co.jp>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-25 11:46:21 +02:00
Hailong Liu
f3d133ee0a sched/rt: Restore rt_runtime after disabling RT_RUNTIME_SHARE
NO_RT_RUNTIME_SHARE feature is used to prevent a CPU borrow enough
runtime with a spin-rt-task.

However, if RT_RUNTIME_SHARE feature is enabled and rt_rq has borrowd
enough rt_runtime at the beginning, rt_runtime can't be restored to
its initial bandwidth rt_runtime after we disable RT_RUNTIME_SHARE.

E.g. on my PC with 4 cores, procedure to reproduce:
1) Make sure  RT_RUNTIME_SHARE is enabled
 cat /sys/kernel/debug/sched_features
  GENTLE_FAIR_SLEEPERS START_DEBIT NO_NEXT_BUDDY LAST_BUDDY
  CACHE_HOT_BUDDY WAKEUP_PREEMPTION NO_HRTICK NO_DOUBLE_TICK
  LB_BIAS NONTASK_CAPACITY TTWU_QUEUE NO_SIS_AVG_CPU SIS_PROP
  NO_WARN_DOUBLE_CLOCK RT_PUSH_IPI RT_RUNTIME_SHARE NO_LB_MIN
  ATTACH_AGE_LOAD WA_IDLE WA_WEIGHT WA_BIAS
2) Start a spin-rt-task
 ./loop_rr &
3) set affinity to the last cpu
 taskset -p 8 $pid_of_loop_rr
4) Observe that last cpu have borrowed enough runtime.
 cat /proc/sched_debug | grep rt_runtime
  .rt_runtime                    : 950.000000
  .rt_runtime                    : 900.000000
  .rt_runtime                    : 950.000000
  .rt_runtime                    : 1000.000000
5) Disable RT_RUNTIME_SHARE
 echo NO_RT_RUNTIME_SHARE > /sys/kernel/debug/sched_features
6) Observe that rt_runtime can not been restored
 cat /proc/sched_debug | grep rt_runtime
  .rt_runtime                    : 950.000000
  .rt_runtime                    : 900.000000
  .rt_runtime                    : 950.000000
  .rt_runtime                    : 1000.000000

This patch help to restore rt_runtime after we disable
RT_RUNTIME_SHARE.

Signed-off-by: Hailong Liu <liu.hailong6@zte.com.cn>
Signed-off-by: Jiang Biao <jiang.biao2@zte.com.cn>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: zhong.weidong@zte.com.cn
Link: http://lkml.kernel.org/r/1531874815-39357-1-git-send-email-liu.hailong6@zte.com.cn
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-25 11:29:08 +02:00
Daniel Bristot de Oliveira
840d719604 sched/deadline: Update rq_clock of later_rq when pushing a task
Daniel Casini got this warn while running a DL task here at RetisLab:

  [  461.137582] ------------[ cut here ]------------
  [  461.137583] rq->clock_update_flags < RQCF_ACT_SKIP
  [  461.137599] WARNING: CPU: 4 PID: 2354 at kernel/sched/sched.h:967 assert_clock_updated.isra.32.part.33+0x17/0x20
      [a ton of modules]
  [  461.137646] CPU: 4 PID: 2354 Comm: label_image Not tainted 4.18.0-rc4+ #3
  [  461.137647] Hardware name: ASUS All Series/Z87-K, BIOS 0801 09/02/2013
  [  461.137649] RIP: 0010:assert_clock_updated.isra.32.part.33+0x17/0x20
  [  461.137649] Code: ff 48 89 83 08 09 00 00 eb c6 66 0f 1f 84 00 00 00 00 00 55 48 c7 c7 98 7a 6c a5 c6 05 bc 0d 54 01 01 48 89 e5 e8 a9 84 fb ff <0f> 0b 5d c3 0f 1f 44 00 00 0f 1f 44 00 00 83 7e 60 01 74 0a 48 3b
  [  461.137673] RSP: 0018:ffffa77e08cafc68 EFLAGS: 00010082
  [  461.137674] RAX: 0000000000000000 RBX: ffff8b3fc1702d80 RCX: 0000000000000006
  [  461.137674] RDX: 0000000000000007 RSI: 0000000000000096 RDI: ffff8b3fded164b0
  [  461.137675] RBP: ffffa77e08cafc68 R08: 0000000000000026 R09: 0000000000000339
  [  461.137676] R10: ffff8b3fd060d410 R11: 0000000000000026 R12: ffffffffa4e14e20
  [  461.137677] R13: ffff8b3fdec22940 R14: ffff8b3fc1702da0 R15: ffff8b3fdec22940
  [  461.137678] FS:  00007efe43ee5700(0000) GS:ffff8b3fded00000(0000) knlGS:0000000000000000
  [  461.137679] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  [  461.137680] CR2: 00007efe30000010 CR3: 0000000301744003 CR4: 00000000001606e0
  [  461.137680] Call Trace:
  [  461.137684]  push_dl_task.part.46+0x3bc/0x460
  [  461.137686]  task_woken_dl+0x60/0x80
  [  461.137689]  ttwu_do_wakeup+0x4f/0x150
  [  461.137690]  ttwu_do_activate+0x77/0x80
  [  461.137692]  try_to_wake_up+0x1d6/0x4c0
  [  461.137693]  wake_up_q+0x32/0x70
  [  461.137696]  do_futex+0x7e7/0xb50
  [  461.137698]  __x64_sys_futex+0x8b/0x180
  [  461.137701]  do_syscall_64+0x5a/0x110
  [  461.137703]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
  [  461.137705] RIP: 0033:0x7efe4918ca26
  [  461.137705] Code: 00 00 00 74 17 49 8b 48 20 44 8b 59 10 41 83 e3 30 41 83 fb 20 74 1e be 85 00 00 00 41 ba 01 00 00 00 41 b9 01 00 00 04 0f 05 <48> 3d 01 f0 ff ff 73 1f 31 c0 c3 be 8c 00 00 00 49 89 c8 4d 31 d2
  [  461.137738] RSP: 002b:00007efe43ee4928 EFLAGS: 00000283 ORIG_RAX: 00000000000000ca
  [  461.137739] RAX: ffffffffffffffda RBX: 0000000005094df0 RCX: 00007efe4918ca26
  [  461.137740] RDX: 0000000000000001 RSI: 0000000000000085 RDI: 0000000005094e24
  [  461.137741] RBP: 00007efe43ee49c0 R08: 0000000005094e20 R09: 0000000004000001
  [  461.137741] R10: 0000000000000001 R11: 0000000000000283 R12: 0000000000000000
  [  461.137742] R13: 0000000005094df8 R14: 0000000000000001 R15: 0000000000448a10
  [  461.137743] ---[ end trace 187df4cad2bf7649 ]---

This warning happened in the push_dl_task(), because
__add_running_bw()->cpufreq_update_util() is getting the rq_clock of
the later_rq before its update, which takes place at activate_task().
The fix then is to update the rq_clock before calling add_running_bw().

To avoid double rq_clock_update() call, we set ENQUEUE_NOCLOCK flag to
activate_task().

Reported-by: Daniel Casini <daniel.casini@santannapisa.it>
Signed-off-by: Daniel Bristot de Oliveira <bristot@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Juri Lelli <juri.lelli@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luca Abeni <luca.abeni@santannapisa.it>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tommaso Cucinotta <tommaso.cucinotta@santannapisa.it>
Fixes: e0367b1267 sched/deadline: Move CPU frequency selection triggering points
Link: http://lkml.kernel.org/r/ca31d073a4788acf0684a8b255f14fea775ccf20.1532077269.git.bristot@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-25 11:29:08 +02:00
Isaac J. Manjarres
2610e88946 stop_machine: Disable preemption after queueing stopper threads
This commit:

  9fb8d5dc4b ("stop_machine, Disable preemption when waking two stopper threads")

does not fully address the race condition that can occur
as follows:

On one CPU, call it CPU 3, thread 1 invokes
cpu_stop_queue_two_works(2, 3,...), and the execution is such
that thread 1 queues the works for migration/2 and migration/3,
and is preempted after releasing the locks for migration/2 and
migration/3, but before waking the threads.

Then, On CPU 2, a kworker, call it thread 2, is running,
and it invokes cpu_stop_queue_two_works(1, 2,...), such that
thread 2 queues the works for migration/1 and migration/2.
Meanwhile, on CPU 3, thread 1 resumes execution, and wakes
migration/2 and migration/3. This means that when CPU 2
releases the locks for migration/1 and migration/2, but before
it wakes those threads, it can be preempted by migration/2.

If thread 2 is preempted by migration/2, then migration/2 will
execute the first work item successfully, since migration/3
was woken up by CPU 3, but when it goes to execute the second
work item, it disables preemption, calls multi_cpu_stop(),
and thus, CPU 2 will wait forever for migration/1, which should
have been woken up by thread 2. However migration/1 cannot be
woken up by thread 2, since it is a kworker, so it is affine to
CPU 2, but CPU 2 is running migration/2 with preemption
disabled, so thread 2 will never run.

Disable preemption after queueing works for stopper threads
to ensure that the operation of queueing the works and waking
the stopper threads is atomic.

Co-Developed-by: Prasad Sodagudi <psodagud@codeaurora.org>
Co-Developed-by: Pavankumar Kondeti <pkondeti@codeaurora.org>
Signed-off-by: Isaac J. Manjarres <isaacm@codeaurora.org>
Signed-off-by: Prasad Sodagudi <psodagud@codeaurora.org>
Signed-off-by: Pavankumar Kondeti <pkondeti@codeaurora.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bigeasy@linutronix.de
Cc: gregkh@linuxfoundation.org
Cc: matt@codeblueprint.co.uk
Fixes: 9fb8d5dc4b ("stop_machine, Disable preemption when waking two stopper threads")
Link: http://lkml.kernel.org/r/1531856129-9871-1-git-send-email-isaacm@codeaurora.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-25 11:25:08 +02:00
Yi Wang
6cd0c583b0 sched/topology: Check variable group before dereferencing it
The 'group' variable in sched_domain_debug_one() is not checked
when firstly used in cpumask_test_cpu(cpu, sched_group_span(group)),
but it might be NULL (it is checked later in the following while loop)
and may cause NULL pointer dereference.

We need to check it before using to avoid NULL dereference.

Signed-off-by: Yi Wang <wang.yi59@zte.com.cn>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Jiang Biao <jiang.biao2@zte.com.cn>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: zhong.weidong@zte.com.cn
Link: http://lkml.kernel.org/r/1532319547-33335-1-git-send-email-wang.yi59@zte.com.cn
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-25 11:25:07 +02:00
Waiman Long
c0dc373a78 locking/pvqspinlock/x86: Use LOCK_PREFIX in __pv_queued_spin_unlock() assembly code
The LOCK_PREFIX macro should be used in the __raw_callee_save___pv_queued_spin_unlock()
assembly code, so that the lock prefix can be patched out on UP systems.

Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Joe Mario <jmario@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Link: http://lkml.kernel.org/r/1531858560-21547-1-git-send-email-longman@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-25 11:22:20 +02:00
Peter Rosin
7b94ea5051 i2c/mux, locking/core: Annotate the nested rt_mutex usage
If an i2c topology has instances of nested muxes, then a lockdep splat
is produced when when i2c_parent_lock_bus() is called.  Here is an
example:

  ============================================
  WARNING: possible recursive locking detected
  --------------------------------------------
  insmod/68159 is trying to acquire lock:
    (i2c_register_adapter#2){+.+.}, at: i2c_parent_lock_bus+0x32/0x50 [i2c_mux]

  but task is already holding lock:
    (i2c_register_adapter#2){+.+.}, at: i2c_parent_lock_bus+0x32/0x50 [i2c_mux]

  other info that might help us debug this:
    Possible unsafe locking scenario:

          CPU0
          ----
     lock(i2c_register_adapter#2);
     lock(i2c_register_adapter#2);

    *** DEADLOCK ***

    May be due to missing lock nesting notation

  1 lock held by insmod/68159:
    #0:  (i2c_register_adapter#2){+.+.}, at: i2c_parent_lock_bus+0x32/0x50 [i2c_mux]

  stack backtrace:
  CPU: 13 PID: 68159 Comm: insmod Tainted: G           O
  Call Trace:
    dump_stack+0x67/0x98
    __lock_acquire+0x162e/0x1780
    lock_acquire+0xba/0x200
    rt_mutex_lock+0x44/0x60
    i2c_parent_lock_bus+0x32/0x50 [i2c_mux]
    i2c_parent_lock_bus+0x3e/0x50 [i2c_mux]
    i2c_smbus_xfer+0xf0/0x700
    i2c_smbus_read_byte+0x42/0x70
    my2c_init+0xa2/0x1000 [my2c]
    do_one_initcall+0x51/0x192
    do_init_module+0x62/0x216
    load_module+0x20f9/0x2b50
    SYSC_init_module+0x19a/0x1c0
    SyS_init_module+0xe/0x10
    do_syscall_64+0x6c/0x1a0
    entry_SYSCALL_64_after_hwframe+0x42/0xb7

Reported-by: John Sperbeck <jsperbeck@google.com>
Tested-by: John Sperbeck <jsperbeck@google.com>
Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Deepa Dinamani <deepadinamani@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Chang <dpf@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Wolfram Sang <wsa@the-dreams.de>
Link: http://lkml.kernel.org/r/20180720083914.1950-3-peda@axentia.se
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-25 11:22:20 +02:00