Commit graph

79307 commits

Author SHA1 Message Date
Will Deacon
9d3af4b448 mm: Pass 'address' to map to do_set_pte() and drop FAULT_FLAG_PREFAULT
Rather than modifying the 'address' field of the 'struct vm_fault'
passed to do_set_pte(), leave that to identify the real faulting address
and pass in the virtual address to be mapped by the new pte as a
separate argument.

This makes FAULT_FLAG_PREFAULT redundant, as a prefault entry can be
identified simply by comparing the new address parameter with the
faulting address, so remove the redundant flag at the same time.

Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Will Deacon <will@kernel.org>
2021-01-21 12:50:18 +00:00
Will Deacon
742d33729a mm: Move immutable fields of 'struct vm_fault' into anonymous struct
'struct vm_fault' contains both information about the fault being
serviced alongside mutable fields contributing to the state of the
fault-handling logic. Unfortunately, the distinction between the two is
not clear-cut, and a number of callers end up manipulating the structure
temporarily before restoring it when returning.

Try to clean this up by moving the immutable fault information into an
anonymous struct, which will later be marked as 'const'. Ideally, the
'flags' field would be part of the new structure too, but it seems as
though the ->page_mkwrite() path is not ready for this yet.

Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/r/CAHk-=whYs9XsO88iqJzN6NC=D-dp2m0oYXuOoZ=eWnvv=5OA+w@mail.gmail.com
Signed-off-by: Will Deacon <will@kernel.org>
2021-01-21 12:49:54 +00:00
Dmitry Osipenko
51dfb6ca37
regulator: consumer: Add missing stubs to regulator/consumer.h
Add missing stubs to regulator/consumer.h in order to fix COMPILE_TEST
of the kernel. In particular this should fix compile-testing of OPP core
because of a missing stub for regulator_sync_voltage().

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Link: https://lore.kernel.org/r/20210120205844.12658-1-digetx@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2021-01-21 12:35:42 +00:00
Kyle Tso
8dea75e113 usb: typec: tcpm: Protocol Error handling
PD3.0 Spec 6.8.1 describes how to handle Protocol Error. There are
general rules defined in Table 6-61 which regulate incoming Message
handling. If the incoming Message is unexpected, unsupported, or
unrecognized, Protocol Error occurs. Follow the rules to handle these
situations. Also consider PD2.0 connection (PD2.0 Spec Table 6-36) for
backward compatibilities.

To know the types of AMS in all the recipient's states, identify those
AMS who are initiated by the port partner but not yet recorded in the
current code.

Besides, introduce a new state CHUNK_NOT_SUPP to delay the NOT_SUPPORTED
message after receiving a chunked message.

Tested-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Kyle Tso <kyletso@google.com>
Link: https://lore.kernel.org/r/20210114145053.1952756-3-kyletso@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-21 12:23:32 +01:00
Kyle Tso
0908c5aca3 usb: typec: tcpm: AMS and Collision Avoidance
This patch provides the implementation of Collision Avoidance introduced
in PD3.0. The start of each Atomic Message Sequence (AMS) initiated by
the port will be denied if the current AMS is not interruptible. The
Source port will set the CC to SinkTxNG if it is going to initiate an
AMS, and SinkTxOk otherwise. Meanwhile, any AMS initiated by a Sink port
will be denied in TCPM if the port partner (Source) sets SinkTxNG except
for HARD_RESET and SOFT_RESET.

Tested-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Kyle Tso <kyletso@google.com>
Link: https://lore.kernel.org/r/20210114145053.1952756-2-kyletso@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-21 12:23:32 +01:00
Greg Kroah-Hartman
3cfade53c7 Merge branch 'tty-splice' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux into tty-next
Fixes both the "splice/sendfile to a tty" and "splice/sendfile from a
tty" regression from 5.10.

* 'tty-splice' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux:
  tty: teach the n_tty ICANON case about the new "cookie continuations" too
  tty: teach n_tty line discipline about the new "cookie continuations"
  tty: clean up legacy leftovers from n_tty line discipline
  tty: implement read_iter
  tty: convert tty_ldisc_ops 'read()' function to take a kernel pointer
  tty: implement write_iter
2021-01-21 09:40:55 +01:00
Manivannan Sadhasivam
cdce2663ff Merge branch 'mhi-ath11k-immutable' into mhi-next 2021-01-21 13:23:01 +05:30
Carl Huang
6ffcc18d9c mhi: use irq_flags if controller driver configures it
If controller driver has specified the irq_flags, mhi uses this specified
irq_flags. Otherwise, mhi uses default irq_flags.

The purpose of this change is to support one MSI vector for QCA6390.
MHI will use one same MSI vector too in this scenario.

In case of one MSI vector, IRQ_NO_BALANCING is needed when irq handler
is requested. The reason is if irq migration happens, the msi_data may
change too. However, the msi_data is already programmed to QCA6390
hardware during initialization phase. This msi_data inconsistence will
result in crash in kernel.

Another issue is in case of one MSI vector, IRQF_NO_SUSPEND will trigger
WARNINGS because QCA6390 wants to disable the IRQ during the suspend.

To avoid above two issues, QCA6390 driver specifies the irq_flags in case
of one MSI vector when mhi_register_controller is called.

Signed-off-by: Carl Huang <cjhuang@codeaurora.org>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
2021-01-21 13:07:40 +05:30
Loic Poulain
fcba4b2047 mhi: unconstify mhi_event_config
Some parameters may have to be determined at runtime.
It is the case for the event ring MSI vector.

Signed-off-by: Loic Poulain <loic.poulain@linaro.org>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
2021-01-21 13:05:53 +05:30
wenxu
7baf2429a1 net/sched: cls_flower add CT_FLAGS_INVALID flag support
This patch add the TCA_FLOWER_KEY_CT_FLAGS_INVALID flag to
match the ct_state with invalid for conntrack.

Signed-off-by: wenxu <wenxu@ucloud.cn>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Link: https://lore.kernel.org/r/1611045110-682-1-git-send-email-wenxu@ucloud.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-20 21:09:44 -08:00
Linus Torvalds
3b830a9c34 tty: convert tty_ldisc_ops 'read()' function to take a kernel pointer
The tty line discipline .read() function was passed the final user
pointer destination as an argument, which doesn't match the 'write()'
function, and makes it very inconvenient to do a splice method for
ttys.

This is a conversion to use a kernel buffer instead.

NOTE! It does this by passing the tty line discipline ->read() function
an additional "cookie" to fill in, and an offset into the cookie data.

The line discipline can fill in the cookie data with its own private
information, and then the reader will repeat the read until either the
cookie is cleared or it runs out of data.

The only real user of this is N_HDLC, which can use this to handle big
packets, even if the kernel buffer is smaller than the whole packet.

Cc: Christoph Hellwig <hch@lst.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-01-20 16:48:47 -08:00
Stanislav Fomichev
a9ed15dae0 bpf: Split cgroup_bpf_enabled per attach type
When we attach any cgroup hook, the rest (even if unused/unattached) start
to contribute small overhead. In particular, the one we want to avoid is
__cgroup_bpf_run_filter_skb which does two redirections to get to
the cgroup and pushes/pulls skb.

Let's split cgroup_bpf_enabled to be per-attach to make sure
only used attach types trigger.

I've dropped some existing high-level cgroup_bpf_enabled in some
places because BPF_PROG_CGROUP_XXX_RUN macros usually have another
cgroup_bpf_enabled check.

I also had to copy-paste BPF_CGROUP_RUN_SA_PROG_LOCK for
GETPEERNAME/GETSOCKNAME because type for cgroup_bpf_enabled[type]
has to be constant and known at compile time.

Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20210115163501.805133-4-sdf@google.com
2021-01-20 14:23:00 -08:00
Stanislav Fomichev
20f2505fb4 bpf: Try to avoid kzalloc in cgroup/{s,g}etsockopt
When we attach a bpf program to cgroup/getsockopt any other getsockopt()
syscall starts incurring kzalloc/kfree cost.

Let add a small buffer on the stack and use it for small (majority)
{s,g}etsockopt values. The buffer is small enough to fit into
the cache line and cover the majority of simple options (most
of them are 4 byte ints).

It seems natural to do the same for setsockopt, but it's a bit more
involved when the BPF program modifies the data (where we have to
kmalloc). The assumption is that for the majority of setsockopt
calls (which are doing pure BPF options or apply policy) this
will bring some benefit as well.

Without this patch (we remove about 1% __kmalloc):
     3.38%     0.07%  tcp_mmap  [kernel.kallsyms]  [k] __cgroup_bpf_run_filter_getsockopt
            |
             --3.30%--__cgroup_bpf_run_filter_getsockopt
                       |
                        --0.81%--__kmalloc

Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20210115163501.805133-3-sdf@google.com
2021-01-20 14:23:00 -08:00
Stanislav Fomichev
9cacf81f81 bpf: Remove extra lock_sock for TCP_ZEROCOPY_RECEIVE
Add custom implementation of getsockopt hook for TCP_ZEROCOPY_RECEIVE.
We skip generic hooks for TCP_ZEROCOPY_RECEIVE and have a custom
call in do_tcp_getsockopt using the on-stack data. This removes
3% overhead for locking/unlocking the socket.

Without this patch:
     3.38%     0.07%  tcp_mmap  [kernel.kallsyms]  [k] __cgroup_bpf_run_filter_getsockopt
            |
             --3.30%--__cgroup_bpf_run_filter_getsockopt
                       |
                        --0.81%--__kmalloc

With the patch applied:
     0.52%     0.12%  tcp_mmap  [kernel.kallsyms]  [k] __cgroup_bpf_run_filter_getsockopt_kern

Note, exporting uapi/tcp.h requires removing netinet/tcp.h
from test_progs.h because those headers have confliciting
definitions.

Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20210115163501.805133-2-sdf@google.com
2021-01-20 14:23:00 -08:00
Jakub Kicinski
0fe2f273ab Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Conflicts:

drivers/net/can/dev.c
  commit 03f16c5075 ("can: dev: can_restart: fix use after free bug")
  commit 3e77f70e73 ("can: dev: move driver related infrastructure into separate subdir")

  Code move.

drivers/net/dsa/b53/b53_common.c
 commit 8e4052c32d ("net: dsa: b53: fix an off by one in checking "vlan->vid"")
 commit b7a9e0da2d ("net: switchdev: remove vid_begin -> vid_end range from VLAN objects")

 Field rename.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-20 12:16:11 -08:00
Rafał Miłecki
149ae80b1d soc: bcm: brcmstb: add stubs for getting platform IDs
Some brcmstb drivers may be shared with other SoC families. E.g. the
same USB PHY block is shared by brcmstb and BCM4908.

To avoid building brcmstb common code on non-brcmstb platforms we need
stubs for:
1. brcmstb_get_family_id()
2. brcmstb_get_product_id()
(to avoid "undefined reference to" errors).

With this change PHY_BRCM_USB will not have to unconditionally select
SOC_BRCMSTB anymore.

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
2021-01-20 12:07:23 -08:00
Linus Torvalds
75439bc439 Networking fixes for 5.11-rc5, including fixes from bpf, wireless,
and can trees.
 
 Current release - regressions:
 
  - nfc: nci: fix the wrong NCI_CORE_INIT parameters
 
 Current release - new code bugs:
 
  - bpf: allow empty module BTFs
 
 Previous releases - regressions:
 
  - bpf: fix signed_{sub,add32}_overflows type handling
 
  - tcp: do not mess with cloned skbs in tcp_add_backlog()
 
  - bpf: prevent double bpf_prog_put call from bpf_tracing_prog_attach
 
  - bpf: don't leak memory in bpf getsockopt when optlen == 0
 
  - tcp: fix potential use-after-free due to double kfree()
 
  - mac80211: fix encryption issues with WEP
 
  - devlink: use right genl user_ptr when handling port param get/set
 
  - ipv6: set multicast flag on the multicast route
 
  - tcp: fix TCP_USER_TIMEOUT with zero window
 
 Previous releases - always broken:
 
  - bpf: local storage helpers should check nullness of owner ptr passed
 
  - mac80211: fix incorrect strlen of .write in debugfs
 
  - cls_flower: call nla_ok() before nla_next()
 
  - skbuff: back tiny skbs with kmalloc() in __netdev_alloc_skb() too
 
 Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag 'net-5.11-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

Pull networking fixes from Jakub Kicinski:
 "Networking fixes for 5.11-rc5, including fixes from bpf, wireless, and
  can trees.

  Current release - regressions:

   - nfc: nci: fix the wrong NCI_CORE_INIT parameters

  Current release - new code bugs:

   - bpf: allow empty module BTFs

  Previous releases - regressions:

   - bpf: fix signed_{sub,add32}_overflows type handling

   - tcp: do not mess with cloned skbs in tcp_add_backlog()

   - bpf: prevent double bpf_prog_put call from bpf_tracing_prog_attach

   - bpf: don't leak memory in bpf getsockopt when optlen == 0

   - tcp: fix potential use-after-free due to double kfree()

   - mac80211: fix encryption issues with WEP

   - devlink: use right genl user_ptr when handling port param get/set

   - ipv6: set multicast flag on the multicast route

   - tcp: fix TCP_USER_TIMEOUT with zero window

  Previous releases - always broken:

   - bpf: local storage helpers should check nullness of owner ptr passed

   - mac80211: fix incorrect strlen of .write in debugfs

   - cls_flower: call nla_ok() before nla_next()

   - skbuff: back tiny skbs with kmalloc() in __netdev_alloc_skb() too"

* tag 'net-5.11-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (52 commits)
  net: systemport: free dev before on error path
  net: usb: cdc_ncm: don't spew notifications
  net: mscc: ocelot: Fix multicast to the CPU port
  tcp: Fix potential use-after-free due to double kfree()
  bpf: Fix signed_{sub,add32}_overflows type handling
  can: peak_usb: fix use after free bugs
  can: vxcan: vxcan_xmit: fix use after free bug
  can: dev: can_restart: fix use after free bug
  tcp: fix TCP socket rehash stats mis-accounting
  net: dsa: b53: fix an off by one in checking "vlan->vid"
  tcp: do not mess with cloned skbs in tcp_add_backlog()
  selftests: net: fib_tests: remove duplicate log test
  net: nfc: nci: fix the wrong NCI_CORE_INIT parameters
  sh_eth: Fix power down vs. is_opened flag ordering
  net: Disable NETIF_F_HW_TLS_RX when RXCSUM is disabled
  netfilter: rpfilter: mask ecn bits before fib lookup
  udp: mask TOS bits in udp_v4_early_demux()
  xsk: Clear pool even for inactive queues
  bpf: Fix helper bpf_map_peek_elem_proto pointing to wrong callback
  sh_eth: Make PHY access aware of Runtime PM to fix reboot crash
  ...
2021-01-20 11:52:21 -08:00
Aswath Govindraju
f6f1f8e6e3 misc: eeprom_93xx46: Add quirk to support Microchip 93LC46B eeprom
A dummy zero bit is sent preceding the data during a read transfer by the
Microchip 93LC46B eeprom (section 2.7 of[1]). This results in right shift
of data during a read. In order to ignore this bit a quirk can be added to
send an extra zero bit after the read address.

Add a quirk to ignore the zero bit sent before data by adding a zero bit
after the read address.

[1] - https://www.mouser.com/datasheet/2/268/20001749K-277859.pdf

Signed-off-by: Aswath Govindraju <a-govindraju@ti.com>
Link: https://lore.kernel.org/r/20210105105817.17644-3-a-govindraju@ti.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-20 18:52:12 +01:00
Grant Grundler
de658a195e net: usb: cdc_ncm: don't spew notifications
RTL8156 sends notifications about every 32ms.
Only display/log notifications when something changes.

This issue has been reported by others:
	https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1832472
	https://lkml.org/lkml/2020/8/27/1083

...
[785962.779840] usb 1-1: new high-speed USB device number 5 using xhci_hcd
[785962.929944] usb 1-1: New USB device found, idVendor=0bda, idProduct=8156, bcdDevice=30.00
[785962.929949] usb 1-1: New USB device strings: Mfr=1, Product=2, SerialNumber=6
[785962.929952] usb 1-1: Product: USB 10/100/1G/2.5G LAN
[785962.929954] usb 1-1: Manufacturer: Realtek
[785962.929956] usb 1-1: SerialNumber: 000000001
[785962.991755] usbcore: registered new interface driver cdc_ether
[785963.017068] cdc_ncm 1-1:2.0: MAC-Address: 00:24:27:88:08:15
[785963.017072] cdc_ncm 1-1:2.0: setting rx_max = 16384
[785963.017169] cdc_ncm 1-1:2.0: setting tx_max = 16384
[785963.017682] cdc_ncm 1-1:2.0 usb0: register 'cdc_ncm' at usb-0000:00:14.0-1, CDC NCM, 00:24:27:88:08:15
[785963.019211] usbcore: registered new interface driver cdc_ncm
[785963.023856] usbcore: registered new interface driver cdc_wdm
[785963.025461] usbcore: registered new interface driver cdc_mbim
[785963.038824] cdc_ncm 1-1:2.0 enx002427880815: renamed from usb0
[785963.089586] cdc_ncm 1-1:2.0 enx002427880815: network connection: disconnected
[785963.121673] cdc_ncm 1-1:2.0 enx002427880815: network connection: disconnected
[785963.153682] cdc_ncm 1-1:2.0 enx002427880815: network connection: disconnected
...

This is about 2KB per second and will overwrite all contents of a 1MB
dmesg buffer in under 10 minutes rendering them useless for debugging
many kernel problems.

This is also an extra 180 MB/day in /var/logs (or 1GB per week) rendering
the majority of those logs useless too.

When the link is up (expected state), spew amount is >2x higher:
...
[786139.600992] cdc_ncm 2-1:2.0 enx002427880815: network connection: connected
[786139.632997] cdc_ncm 2-1:2.0 enx002427880815: 2500 mbit/s downlink 2500 mbit/s uplink
[786139.665097] cdc_ncm 2-1:2.0 enx002427880815: network connection: connected
[786139.697100] cdc_ncm 2-1:2.0 enx002427880815: 2500 mbit/s downlink 2500 mbit/s uplink
[786139.729094] cdc_ncm 2-1:2.0 enx002427880815: network connection: connected
[786139.761108] cdc_ncm 2-1:2.0 enx002427880815: 2500 mbit/s downlink 2500 mbit/s uplink
...

Chrome OS cannot support RTL8156 until this is fixed.

Signed-off-by: Grant Grundler <grundler@chromium.org>
Reviewed-by: Hayes Wang <hayeswang@realtek.com>
Link: https://lore.kernel.org/r/20210120011208.3768105-1-grundler@chromium.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-20 09:01:55 -08:00
Pi-Hsun Shih
9f77c58d65 platform/chrome: cros_ec_commands: Add host command to keep AP off after EC reset.
Add command to EC_CMD_REBOOT_EC to reset EC but don't boot AP.

Signed-off-by: Pi-Hsun Shih <pihsun@chromium.org>
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Link: https://lore.kernel.org/r/20201221041231.14516-1-pihsun@chromium.org
2021-01-20 16:19:17 +01:00
Will Deacon
46bdb4277f mm: Allow architectures to request 'old' entries when prefaulting
Commit 5c0a85fad9 ("mm: make faultaround produce old ptes") changed
the "faultaround" behaviour to initialise prefaulted PTEs as 'old',
since this avoids vmscan wrongly assuming that they are hot, despite
having never been explicitly accessed by userspace. The change has been
shown to benefit numerous arm64 micro-architectures (with hardware
access flag) running Android, where both application launch latency and
direct reclaim time are significantly reduced (by 10%+ and ~80%
respectively).

Unfortunately, commit 315d09bf30 ("Revert "mm: make faultaround
produce old ptes"") reverted the change due to it being identified as
the cause of a ~6% regression in unixbench on x86. Experiments on a
variety of recent arm64 micro-architectures indicate that unixbench is
not affected by the original commit, which appears to yield a 0-1%
performance improvement.

Since one size does not fit all for the initial state of prefaulted
PTEs, introduce arch_wants_old_prefaulted_pte(), which allows an
architecture to opt-in to 'old' prefaulted PTEs at runtime based on
whatever criteria it may have.

Cc: Jan Kara <jack@suse.cz>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Reported-by: Vinayak Menon <vinmenon@codeaurora.org>
Signed-off-by: Will Deacon <will@kernel.org>
2021-01-20 14:46:04 +00:00
Kirill A. Shutemov
f9ce0be71d mm: Cleanup faultaround and finish_fault() codepaths
alloc_set_pte() has two users with different requirements: in the
faultaround code, it called from an atomic context and PTE page table
has to be preallocated. finish_fault() can sleep and allocate page table
as needed.

PTL locking rules are also strange, hard to follow and overkill for
finish_fault().

Let's untangle the mess. alloc_set_pte() has gone now. All locking is
explicit.

The price is some code duplication to handle huge pages in faultaround
path, but it should be fine, having overall improvement in readability.

Link: https://lore.kernel.org/r/20201229132819.najtavneutnf7ajp@box
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
[will: s/from from/from/ in comment; spotted by willy]
Signed-off-by: Will Deacon <will@kernel.org>
2021-01-20 14:46:04 +00:00
Christian König
7621350c6b drm/syncobj: make lockdep complain on WAIT_FOR_SUBMIT v3
DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT can't be used when we hold locks
since we are basically waiting for userspace to do something.

Holding a lock while doing so can trivial deadlock with page faults
etc...

So make lockdep complain when a driver tries to do this.

v2: Add lockdep_assert_none_held() macro.
v3: Add might_sleep() and also use lockdep_assert_none_held() in the
    IOCTL path.

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://patchwork.freedesktop.org/patch/414944/
2021-01-20 15:05:45 +01:00
Linus Walleij
93cc26fa8f backlight: lms283gf05: Convert to GPIO descriptors
This converts the lms283gf05 backlight driver to use GPIO
descriptors and switches the single PXA Palm Z2 device
over to defining these.

Since the platform data was only used to convey GPIO
information we can delete the platform data header.

Notice that we define the proper active low semantics in
the board file GPIO descriptor table (active low) and
assert the reset line by bringing it to "1" (asserted).

Cc: Marek Vasut <marex@denx.de>
Cc: Haojian Zhuang <haojian.zhuang@gmail.com>
Cc: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Daniel Mack <daniel@zonque.org>
Acked-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2021-01-20 12:47:11 +00:00
Ard Biesheuvel
67c6bb56b6 firmware: smccc: Add SMCCC TRNG function call IDs
The ARM architected TRNG firmware interface, described in ARM spec
DEN0098, define an ARM SMCCC based interface to a true random number
generator, provided by firmware.

Add the definitions of the SMCCC functions as defined by the spec.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Link: https://lore.kernel.org/r/20210106103453.152275-2-andre.przywara@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2021-01-20 12:31:43 +00:00
Lauri Kasanen
e1827807e8 video: fbdev: simplefb: Add "r5g5b5a1" mode
Add "r5g5b5a1" which is used on the N64.

Signed-off-by: Lauri Kasanen <cand@gmx.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210115160102.cf4c85db9f815758716f086f@gmx.com
2021-01-20 12:12:22 +01:00
Jarod Wilson
7b8fc0103b bonding: add a vlan+srcmac tx hashing option
This comes from an end-user request, where they're running multiple VMs on
hosts with bonded interfaces connected to some interest switch topologies,
where 802.3ad isn't an option. They're currently running a proprietary
solution that effectively achieves load-balancing of VMs and bandwidth
utilization improvements with a similar form of transmission algorithm.

Basically, each VM has it's own vlan, so it always sends its traffic out
the same interface, unless that interface fails. Traffic gets split
between the interfaces, maintaining a consistent path, with failover still
available if an interface goes down.

Unlike bond_eth_hash(), this hash function is using the full source MAC
address instead of just the last byte, as there are so few components to
the hash, and in the no-vlan case, we would be returning just the last
byte of the source MAC as the hash value. It's entirely possible to have
two NICs in a bond with the same last byte of their MAC, but not the same
MAC, so this adjustment should guarantee distinct hashes in all cases.

This has been rudimetarily tested to provide similar results to the
proprietary solution it is aiming to replace. A patch for iproute2 is also
posted, to properly support the new mode there as well.

Cc: Jay Vosburgh <j.vosburgh@gmail.com>
Cc: Veaceslav Falico <vfalico@gmail.com>
Cc: Andy Gospodarek <andy@greyhouse.net>
Cc: Thomas Davis <tadavis@lbl.gov>
Signed-off-by: Jarod Wilson <jarod@redhat.com>
Link: https://lore.kernel.org/r/20210119010927.1191922-1-jarod@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-19 19:30:32 -08:00
Parav Pandit
de641d74fb Revert "RDMA/mlx5: Fix devlink deadlock on net namespace deletion"
This reverts commit fbdd0049d9.

Due to commit in fixes tag, netdevice events were received only in one net
namespace of mlx5_core_dev. Due to this when netdevice events arrive in
net namespace other than net namespace of mlx5_core_dev, they are missed.

This results in empty GID table due to RDMA device being detached from its
net device.

Hence, revert back to receive netdevice events in all net namespaces to
restore back RDMA functionality in non init_net net namespace. The
deadlock will have to be addressed in another patch.

Fixes: fbdd0049d9 ("RDMA/mlx5: Fix devlink deadlock on net namespace deletion")
Link: https://lore.kernel.org/r/20210117092633.10690-1-leon@kernel.org
Signed-off-by: Parav Pandit <parav@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
2021-01-19 20:22:59 -04:00
Xin Long
fa82117010 net: add inline function skb_csum_is_sctp
This patch is to define a inline function skb_csum_is_sctp(), and
also replace all places where it checks if it's a SCTP CSUM skb.
This function would be used later in many networking drivers in
the following patches.

Suggested-by: Alexander Duyck <alexander.duyck@gmail.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Reviewed-by: Alexander Duyck <alexanderduyck@fb.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-19 14:31:25 -08:00
Daniel Lezcano
23ff8529ee thermal/core: Make cooling device state change private
The change of the cooling device state should be used by the governor
or at least by the core code, not by the drivers themselves.

Remove the API usage and move the function declaration to the internal
headers.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Zhang Rui <rui.zhang@intel.com>
Link: https://lore.kernel.org/r/20210118173824.9970-1-daniel.lezcano@linaro.org
2021-01-19 22:31:10 +01:00
Daniel Lezcano
b39d2dd5b5 thermal/core: Remove ms based delay fields
The code does no longer use the ms unit based fields to set the
delays as they are replaced by the jiffies.

Remove them and replace their user to use the jiffies version instead.

Cc: Thara Gopinath <thara.gopinath@linaro.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Reviewed-by: Peter Kästle <peter@piie.net>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20201216220337.839878-3-daniel.lezcano@linaro.org
2021-01-19 22:23:49 +01:00
Daniel Lezcano
17d399cd9c thermal/core: Precompute the delays from msecs to jiffies
The delays are stored in ms units and when the polling function is
called this delay is converted into jiffies at each call.

Instead of doing the conversion again and again, compute the jiffies
at init time and use the value directly when setting the polling.

Cc: Thara Gopinath <thara.gopinath@linaro.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Reviewed-by: Thara Gopinath <thara.gopinath@linaro.org>
Link: https://lore.kernel.org/r/20201216220337.839878-1-daniel.lezcano@linaro.org
2021-01-19 22:23:38 +01:00
Daniel Lezcano
2121496fdc thermal/core: Remove unused macro THERMAL_TRIPS_NONE
The macro THERMAL_TRIPS_NONE is no longer used, remove it.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Thara Gopinath <thara.gopinath@linaro.org>
Link: https://lore.kernel.org/r/20201214233811.485669-6-daniel.lezcano@linaro.org
2021-01-19 22:23:32 +01:00
Daniel Lezcano
a7d6ba14ef thermal/core: Remove the 'forced_passive' option
The code was reorganized in 2012 with the commit 0c01ebbfd3.

The main change is a loop on the trip points array and a unconditional
call to the throttle() ops of the governors for each of them even if
the trip temperature is not reached yet.

With this change, the 'forced_passive' is no longer checked in the
thermal_zone_device_update() function but in the step wise governor's
throttle() callback.

As the force_passive does no belong to the trip point array, the
thermal_zone_device_update() can not compare with the specified
passive temperature, thus does not detect the passive limit has been
crossed. Consequently, throttle() is never called and the
'forced_passive' branch is unreached.

In addition, the default processor cooling device is not automatically
bound to the thermal zone if there is not passive trip point, thus the
'forced_passive' can not operate.

If there is an active trip point, then the throttle function will be
called to mitigate at this temperature and the 'forced_passive' will
override the mitigation of the active trip point in this case but with
the default cooling device bound to the thermal zone, so usually a
fan, and that is not a passive cooling effect.

Given the regression exists since more than 8 years, nobody complained
and at the best of my knowledge there is no bug open in
https://bugzilla.kernel.org, it is reasonable to say it is unused.

Remove the 'forced_passive' related code.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Thara Gopinath <thara.gopinath@linaro.org>
Link: https://lore.kernel.org/r/20201214233811.485669-1-daniel.lezcano@linaro.org
2021-01-19 22:22:45 +01:00
Geert Uytterhoeven
8eed01b5ca mdio-bitbang: Export mdiobb_{read,write}()
Export mdiobb_read() and mdiobb_write(), so Ethernet controller drivers
can call them from their MDIO read/write wrappers.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-19 12:02:20 -08:00
Alexander Lobakin
7eab14de73 mdio, phy: fix -Wshadow warnings triggered by nested container_of()
container_of() macro hides a local variable '__mptr' inside. This
becomes a problem when several container_of() are nested in each
other within single line or plain macros.
As C preprocessor doesn't support generating random variable names,
the sole solution is to avoid defining macros that consist only of
container_of() calls, or they will self-shadow '__mptr' each time:

In file included from ./include/linux/bitmap.h:10,
                 from drivers/net/phy/phy_device.c:12:
drivers/net/phy/phy_device.c: In function ‘phy_device_release’:
./include/linux/kernel.h:693:8: warning: declaration of ‘__mptr’ shadows a previous local [-Wshadow]
  693 |  void *__mptr = (void *)(ptr);     \
      |        ^~~~~~
./include/linux/phy.h:647:26: note: in expansion of macro ‘container_of’
  647 | #define to_phy_device(d) container_of(to_mdio_device(d), \
      |                          ^~~~~~~~~~~~
./include/linux/mdio.h:52:27: note: in expansion of macro ‘container_of’
   52 | #define to_mdio_device(d) container_of(d, struct mdio_device, dev)
      |                           ^~~~~~~~~~~~
./include/linux/phy.h:647:39: note: in expansion of macro ‘to_mdio_device’
  647 | #define to_phy_device(d) container_of(to_mdio_device(d), \
      |                                       ^~~~~~~~~~~~~~
drivers/net/phy/phy_device.c:217:8: note: in expansion of macro ‘to_phy_device’
  217 |  kfree(to_phy_device(dev));
      |        ^~~~~~~~~~~~~
./include/linux/kernel.h:693:8: note: shadowed declaration is here
  693 |  void *__mptr = (void *)(ptr);     \
      |        ^~~~~~
./include/linux/phy.h:647:26: note: in expansion of macro ‘container_of’
  647 | #define to_phy_device(d) container_of(to_mdio_device(d), \
      |                          ^~~~~~~~~~~~
drivers/net/phy/phy_device.c:217:8: note: in expansion of macro ‘to_phy_device’
  217 |  kfree(to_phy_device(dev));
      |        ^~~~~~~~~~~~~

As they are declared in header files, these warnings are highly
repetitive and very annoying (along with the one from linux/pci.h).

Convert the related macros from linux/{mdio,phy}.h to static inlines
to avoid self-shadowing and potentially improve bug-catching.
No functional changes implied.

Signed-off-by: Alexander Lobakin <alobakin@pm.me>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://lore.kernel.org/r/20210116161246.67075-1-alobakin@pm.me
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-19 11:47:31 -08:00
Ard Biesheuvel
3820749ddc efi/libstub: move TPM related prototypes into efistub.h
Move TPM related definitions that are only used in the EFI stub into
efistub.h, which is a local header.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2021-01-19 17:57:15 +01:00
Ard Biesheuvel
2f19605986 efi/libstub: whitespace cleanup
Trivial whitespace cleanup.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2021-01-19 17:57:15 +01:00
Menglong Dong
93e86295f5 workqueue: fix annotation for WQ_SYSFS
'wq_sysfs_register()' in annotation for 'WQ_SYSFS' is unavailable,
change it to 'workqueue_sysfs_register()'.

Signed-off-by: Menglong Dong <dong.menglong@zte.com.cn>
Reviewed-by: Lai Jiangshan <jiangshanlai@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2021-01-19 10:20:07 -05:00
Yu-Hsuan Hsu
f4d3bd8be4
cros_ec_commands: Add EC_CODEC_I2S_RX_RESET
Add the new command EC_CODEC_I2S_RX_RESET in ec_codec_i2s_rx_subcmd,
which is used for resetting the EC codec.

Signed-off-by: Yu-Hsuan Hsu <yuhsuan@chromium.org>
Acked-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Link: https://lore.kernel.org/r/20210115075301.47995-1-yuhsuan@chromium.org
Signed-off-by: Mark Brown <broonie@kernel.org>
2021-01-19 14:09:22 +00:00
Yishai Hadas
ab0da5a571 net/mlx5: Expose ifc bits for query modify header
Expose ifc bits for query_modify_header_context_in to be used by DEVX.

Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
2021-01-19 07:34:28 +02:00
Tariq Toukan
719a402cf6 net: netdevice: Add operation ndo_sk_get_lower_dev
ndo_sk_get_lower_dev returns the lower netdev that corresponds to
a given socket.
Additionally, we implement a helper netdev_sk_get_lowest_dev() to get
the lowest one in chain.

Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Reviewed-by: Boris Pismenny <borisp@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-18 20:48:39 -08:00
Yue Zou
0627cc334d sony-laptop: Remove unneeded semicolon
Remove a superfluous semicolon after function definition.

Signed-off-by: Yue Zou <zouyue3@huawei.com>
Link: https://lore.kernel.org/r/20210118010137.214378-1-zouyue3@huawei.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2021-01-18 21:39:28 +01:00
Klaus Jensen
20d3bb92e8 nvme-pci: allow use of cmb on v1.4 controllers
Since NVMe v1.4 the Controller Memory Buffer must be explicitly enabled
by the host.

Signed-off-by: Klaus Jensen <k.jensen@samsung.com>
[hch: avoid a local variable and add a comment]
Signed-off-by: Christoph Hellwig <hch@lst.de>
2021-01-18 18:58:18 +01:00
Thinh Nguyen
ead4c12485 usb: gadget: Introduce udc_set_ssp_rate() for SSP
A SuperSpeed Plus device may operate at different speed and lane count
(i.e. gen2x2, gen1x2, or gen2x1). Introduce gadget ops
udc_set_ssp_rate() to set the desire corresponding usb_ssp_rate for
SuperSpeed Plus capable devices.

If the USB device supports different speeds at SuperSpeed Plus, set the
device to operate with the maximum number of lanes and speed.

Signed-off-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Link: https://lore.kernel.org/r/9b85357cdadc02e3f0d653fd05f89eb46af836e1.1610592135.git.Thinh.Nguyen@synopsys.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-18 18:40:08 +01:00
Thinh Nguyen
db615c6264 usb: gadget: Introduce SSP rates and lanes
A USB device controller operating in SuperSpeed Plus may support gen2x1,
gen1x2, and/or gen2x2. Introduce SuperSpeed Plus signaling rate
generation and lane count to usb_gadget with the fields ssp_rate and
max_ssp_rate. The gadget driver can use these to setup the device BOS
descriptor and select the desire operating speed and number of lanes.

Signed-off-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Link: https://lore.kernel.org/r/b6d2196dcc3c73747f91abf9a082b20bbe276cc4.1610592135.git.Thinh.Nguyen@synopsys.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-18 18:39:56 +01:00
Thinh Nguyen
f2fc9ff28d usb: ch9: Add USB 3.2 SSP attributes
In preparation for USB 3.2 dual-lane support, add sublink speed
attribute macros and enum usb_ssp_rate. A USB device that operates in
SuperSpeed Plus may operate at different speed and lane count. These
additional macros and enum values help specifying that.

Signed-off-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Link: https://lore.kernel.org/r/ae9293ebd63a29f2a2035054753534d9eb123d74.1610592135.git.Thinh.Nguyen@synopsys.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-18 18:38:47 +01:00
Douglas Anderson
b33752c300 HID: i2c-hid: Reorganize so ACPI and OF are separate modules
This patch rejiggers the i2c-hid code so that the OF (Open Firmware
aka Device Tree) and ACPI support is separated out a bit.  The OF and
ACPI drivers are now separate modules that wrap the core module.

Essentially, what we're doing here:
* Make "power up" and "power down" a function that can be (optionally)
  implemented by a given user of the i2c-hid core.
* The OF and ACPI modules are drivers on their own, so they implement
  probe / remove / suspend / resume / shutdown.  The core code
  provides implementations that OF and ACPI can call into.

We'll organize this so that we now have 3 modules: the old i2c-hid
module becomes the "core" module and two new modules will depend on
it, handling probing the specific device.

As part of this work, we'll remove the i2c-hid "platform data"
concept since it's not needed.

Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
2021-01-18 16:56:22 +01:00
Paul Cercueil
1b399bb048 kconfig.h: Add IF_ENABLED() macro
IF_ENABLED(CONFIG_FOO, ptr) evaluates to (ptr) if CONFIG_FOO is set to 'y'
or 'm', NULL otherwise. The (ptr) argument must be a pointer.

The IF_ENABLED() macro can be very useful to help GCC drop dead code.

For instance, consider the following:

    #ifdef CONFIG_FOO_SUSPEND
    static int foo_suspend(struct device *dev)
    {
       ...
    }
    #endif

    static struct pm_ops foo_ops = {
	#ifdef CONFIG_FOO_SUSPEND
        .suspend = foo_suspend,
	#endif
    };

While this works, the foo_suspend() macro is compiled conditionally,
only when CONFIG_FOO_SUSPEND is set. This is problematic, as there could
be a build bug in this function, we wouldn't have a way to know unless
the config option is set.

An alternative is to declare foo_suspend() always, but mark it as maybe
unused:

    static int __maybe_unused foo_suspend(struct device *dev)
    {
       ...
    }

    static struct pm_ops foo_ops = {
	#ifdef CONFIG_FOO_SUSPEND
        .suspend = foo_suspend,
	#endif
    };

Again, this works, but the __maybe_unused attribute is required to
instruct the compiler that the function may not be referenced anywhere,
and is safe to remove without making a fuss about it. This makes the
programmer responsible for tagging the functions that can be
garbage-collected.

With this patch, it is now possible to write the following:

    static int foo_suspend(struct device *dev)
    {
       ...
    }

    static struct pm_ops foo_ops = {
        .suspend = IF_ENABLED(CONFIG_FOO_SUSPEND, foo_suspend),
    };

The foo_suspend() function will now be automatically dropped by the
compiler, and it does not require any specific attribute.

Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20201213235447.138271-1-paul@crapouillou.net
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2021-01-18 16:13:51 +01:00
Daniel Vetter
84335675f2 dma-buf: Add debug option
We have too many people abusing the struct page they can get at but
really shouldn't in importers. Aside from that the backing page might
simply not exist (for dynamic p2p mappings) looking at it and using it
e.g. for mmap can also wreak the page handling of the exporter
completely. Importers really must go through the proper interface like
dma_buf_mmap for everything.

I'm semi-tempted to enforce this for dynamic importers since those
really have no excuse at all to break the rules.

Unfortuantely we can't store the right pointers somewhere safe to make
sure we oops on something recognizable, so best is to just wrangle
them a bit by flipping all the bits. At least on x86 kernel addresses
have all their high bits sets and the struct page array is fairly low
in the kernel mapping, so flipping all the bits gives us a very high
pointer in userspace and hence excellent chances for an invalid
dereference.

v2: Add a note to the @map_dma_buf hook that exporters shouldn't do
fancy caching tricks, which would blow up with this address scrambling
trick here (Chris)

Enable by default when CONFIG_DMA_API_DEBUG is enabled.

v3: Only one copy of the mangle/unmangle code (Christian)

v4: #ifdef, not #if (0day)

v5: sg_table can also be an ERR_PTR (Chris, Christian)

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: "Christian König" <christian.koenig@amd.com>
Cc: David Stevens <stevensd@chromium.org>
Cc: linux-media@vger.kernel.org
Cc: linaro-mm-sig@lists.linaro.org
Link: https://patchwork.freedesktop.org/patch/msgid/20210115164739.3958206-1-daniel.vetter@ffwll.ch
2021-01-18 14:26:51 +01:00