commit bcc80dec91ee745b3d66f3e48f0ec2efdea97149 upstream.
read_hv_sched_clock_tsc() assumes that the Hyper-V clock counter is
bigger than the variable hv_sched_clock_offset, which is cached during
early boot, but depending on the timing this assumption may be false
when a hibernated VM starts again (the clock counter starts from 0
again) and is resuming back (Note: hv_init_tsc_clocksource() is not
called during hibernation/resume); consequently,
read_hv_sched_clock_tsc() may return a negative integer (which is
interpreted as a huge positive integer since the return type is u64)
and new kernel messages are prefixed with huge timestamps before
read_hv_sched_clock_tsc() grows big enough (which typically takes
several seconds).
Fix the issue by saving the Hyper-V clock counter just before the
suspend, and using it to correct the hv_sched_clock_offset in
resume. This makes hv tsc page based sched_clock continuous and ensures
that post resume, it starts from where it left off during suspend.
Override x86_platform.save_sched_clock_state and
x86_platform.restore_sched_clock_state routines to correct this as soon
as possible.
Note: if Invariant TSC is available, the issue doesn't happen because
1) we don't register read_hv_sched_clock_tsc() for sched clock:
See commit e5313f1c5404 ("clocksource/drivers/hyper-v: Rework
clocksource and sched clock setup");
2) the common x86 code adjusts TSC similarly: see
__restore_processor_state() -> tsc_verify_tsc_adjust(true) and
x86_platform.restore_sched_clock_state().
Cc: stable@vger.kernel.org
Fixes: 1349401ff1aa ("clocksource/drivers/hyper-v: Suspend/resume Hyper-V clocksource for hibernation")
Co-developed-by: Dexuan Cui <decui@microsoft.com>
Signed-off-by: Dexuan Cui <decui@microsoft.com>
Signed-off-by: Naman Jain <namjain@linux.microsoft.com>
Reviewed-by: Michael Kelley <mhklinux@outlook.com>
Link: https://lore.kernel.org/r/20240917053917.76787-1-namjain@linux.microsoft.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Message-ID: <20240917053917.76787-1-namjain@linux.microsoft.com>
Signed-off-by: Naman Jain <namjain@linux.microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit f1260ff15a71b8fc122b2c9abd8a7abffb6e0168 ]
Like skb_realloc_headroom(), new helper increases headroom of specified skb.
Unlike skb_realloc_headroom(), it does not allocate a new skb if possible;
copies skb->sk on new skb when as needed and frees original skb in case
of failures.
This helps to simplify ip[6]_finish_output2() and a few other similar cases.
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
(cherry picked from commit f1260ff15a71b8fc122b2c9abd8a7abffb6e0168)
Signed-off-by: Harshvardhan Jha <harshvardhan.j.jha@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 54f89b3178d5448dd4457afbb98fc1ab99090a65 ]
When bpf_tcp_ingress() is called, the skmsg is being redirected to the
ingress of the destination socket. Therefore, we should charge its
receive socket buffer, instead of sending socket buffer.
Because sk_rmem_schedule() tests pfmemalloc of skb, we need to
introduce a wrapper and call it for skmsg.
Fixes: 604326b41a6f ("bpf, sockmap: convert to generic sk_msg interface")
Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20241210012039.1669389-2-zijianzhang@bytedance.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 30c2de0a267c04046d89e678cc0067a9cfb455df ]
Fix the following clang compiler warning that is reported if the kernel is
built with W=1:
./include/linux/vmstat.h:518:36: error: arithmetic between different enumeration types ('enum node_stat_item' and 'enum lru_list') [-Werror,-Wenum-enum-conversion]
518 | return node_stat_name(NR_LRU_BASE + lru) + 3; // skip "nr_"
| ~~~~~~~~~~~ ^ ~~~
Link: https://lkml.kernel.org/r/20241212213126.1269116-1-bvanassche@acm.org
Fixes: 9d7ea9a297e6 ("mm/vmstat: add helpers to get vmstat item names for each enum type")
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 900bbaae67e980945dec74d36f8afe0de7556d5a upstream.
Now, the epoll only use wake_up() interface to wake up task.
However, sometimes, there are epoll users which want to use
the synchronous wakeup flag to hint the scheduler, such as
Android binder driver.
So add a wake_up_sync() define, and use the wake_up_sync()
when the sync is true in ep_poll_callback().
Co-developed-by: Jing Xia <jing.xia@unisoc.com>
Signed-off-by: Jing Xia <jing.xia@unisoc.com>
Signed-off-by: Xuewen Yan <xuewen.yan@unisoc.com>
Link: https://lore.kernel.org/r/20240426080548.8203-1-xuewen.yan@unisoc.com
Tested-by: Brian Geffon <bgeffon@google.com>
Reviewed-by: Brian Geffon <bgeffon@google.com>
Reported-by: Benoit Lize <lizeb@google.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Cc: Brian Geffon <bgeffon@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 07a756a49f4b4290b49ea46e089cbe6f79ff8d26 upstream.
If the KVP (or VSS) daemon starts before the VMBus channel's ringbuffer is
fully initialized, we can hit the panic below:
hv_utils: Registering HyperV Utility Driver
hv_vmbus: registering driver hv_utils
...
BUG: kernel NULL pointer dereference, address: 0000000000000000
CPU: 44 UID: 0 PID: 2552 Comm: hv_kvp_daemon Tainted: G E 6.11.0-rc3+ #1
RIP: 0010:hv_pkt_iter_first+0x12/0xd0
Call Trace:
...
vmbus_recvpacket
hv_kvp_onchannelcallback
vmbus_on_event
tasklet_action_common
tasklet_action
handle_softirqs
irq_exit_rcu
sysvec_hyperv_stimer0
</IRQ>
<TASK>
asm_sysvec_hyperv_stimer0
...
kvp_register_done
hvt_op_read
vfs_read
ksys_read
__x64_sys_read
This can happen because the KVP/VSS channel callback can be invoked
even before the channel is fully opened:
1) as soon as hv_kvp_init() -> hvutil_transport_init() creates
/dev/vmbus/hv_kvp, the kvp daemon can open the device file immediately and
register itself to the driver by writing a message KVP_OP_REGISTER1 to the
file (which is handled by kvp_on_msg() ->kvp_handle_handshake()) and
reading the file for the driver's response, which is handled by
hvt_op_read(), which calls hvt->on_read(), i.e. kvp_register_done().
2) the problem with kvp_register_done() is that it can cause the
channel callback to be called even before the channel is fully opened,
and when the channel callback is starting to run, util_probe()->
vmbus_open() may have not initialized the ringbuffer yet, so the
callback can hit the panic of NULL pointer dereference.
To reproduce the panic consistently, we can add a "ssleep(10)" for KVP in
__vmbus_open(), just before the first hv_ringbuffer_init(), and then we
unload and reload the driver hv_utils, and run the daemon manually within
the 10 seconds.
Fix the panic by reordering the steps in util_probe() so the char dev
entry used by the KVP or VSS daemon is not created until after
vmbus_open() has completed. This reordering prevents the race condition
from happening.
Reported-by: Dexuan Cui <decui@microsoft.com>
Fixes: e0fa3e5e7df6 ("Drivers: hv: utils: fix a race on userspace daemons registration")
Cc: stable@vger.kernel.org
Signed-off-by: Michael Kelley <mhklinux@outlook.com>
Acked-by: Wei Liu <wei.liu@kernel.org>
Link: https://lore.kernel.org/r/20241106154247.2271-3-mhklinux@outlook.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Message-ID: <20241106154247.2271-3-mhklinux@outlook.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 349f0086ba8b2a169877d21ff15a4d9da3a60054 upstream.
In 32-bit x86 builds CONFIG_STATIC_CALL_INLINE isn't set, leading to
static_call_initialized not being available.
Define it as "0" in that case.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Fixes: 0ef8047b737d ("x86/static-call: provide a way to do very early static-call updates")
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 0ef8047b737d7480a5d4c46d956e97c190f13050 upstream.
Add static_call_update_early() for updating static-call targets in
very early boot.
This will be needed for support of Xen guest type specific hypercall
functions.
This is part of XSA-466 / CVE-2024-53241.
Reported-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Co-developed-by: Peter Zijlstra <peterz@infradead.org>
Co-developed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
PLB (Protective Load Balancing) is a host based mechanism for load
balancing across switch links. It leverages congestion signals(e.g. ECN)
from transport layer to randomly change the path of the connection
experiencing congestion. PLB changes the path of the connection by
changing the outgoing IPv6 flow label for IPv6 connections (implemented
in Linux by calling sk_rethink_txhash()). Because of this implementation
mechanism, PLB can currently only work for IPv6 traffic. For more
information, see the SIGCOMM 2022 paper:
https://doi.org/10.1145/3544216.3544226
This commit adds new sysctl knobs and sets their default values for
TCP PLB.
Signed-off-by: Mubashir Adnan Qureshi <mubashirq@google.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Juhyung Park <qkrwngud825@gmail.com>
rcv_wnd can be useful to diagnose TCP performance where receiver window
becomes the bottleneck. rehash reports the PLB and timeout triggered
rehash attempts by the TCP connection.
Signed-off-by: Mubashir Adnan Qureshi <mubashirq@google.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Juhyung Park <qkrwngud825@gmail.com>
We had various bugs over the years with code
breaking the assumption that tp->snd_cwnd is greater
than zero.
Lately, syzbot reported the WARN_ON_ONCE(!tp->prior_cwnd) added
in commit 8b8a321ff72c ("tcp: fix zero cwnd in tcp_cwnd_reduction")
can trigger, and without a repro we would have to spend
considerable time finding the bug.
Instead of complaining too late, we want to catch where
and when tp->snd_cwnd is set to an illegal value.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Suggested-by: Yuchung Cheng <ycheng@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Link: https://lore.kernel.org/r/20220405233538.947344-1-eric.dumazet@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Juhyung Park <qkrwngud825@gmail.com>
In order to track CE marks per rate sample (one round trip), TCP needs a
per-skb header field to record the tp->delivered_ce count when the skb
was sent. To make space, we replace the "last_in_flight" field which is
used exclusively for NV congestion control. The stat needed by NV can be
alternatively approximated by existing stats tcp_sock delivered and
mss_cache.
This patch counts the number of packets delivered which have CE marks in
the rate sample, using similar approach of delivery accounting.
Cc: Lawrence Brakmo <brakmo@fb.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Luke Hsiao <lukehsiao@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Juhyung Park <qkrwngud825@gmail.com>
For understanding the relationship between inflight and ECN signals,
to try to find the highest inflight value that has acceptable levels
ECN marking.
Effort: net-tcp_bbr
Origin-9xx-SHA1: 3eba998f2898541406c2666781182200934965a8
Change-Id: I3a964e04cee83e11649a54507043d2dfe769a3b3
Signed-off-by: Juhyung Park <qkrwngud825@gmail.com>
For connections experiencing reordering, RACK can mark packets lost
long after we receive the SACKs/ACKs hinting that the packets were
actually lost.
This means that CC modules cannot easily learn the volume of inflight
data at which packet loss happens by looking at the current inflight
or even the packets in flight when the most recently SACKed packet was
sent. To learn this, CC modules need to know how many packets were in
flight at the time lost packets were sent. This new callback, combined
with TCP_SKB_CB(skb)->tx.in_flight, allows them to learn this.
This also provides a consistent callback that is invoked whether
packets are marked lost upon ACK processing, using the RACK reordering
timer, or at RTO time.
Effort: net-tcp_bbr
Origin-9xx-SHA1: afcbebe3374e4632ac6714d39e4dc8a8455956f4
Change-Id: I54826ab53df636be537e5d3c618a46145d12d51a
Signed-off-by: Juhyung Park <qkrwngud825@gmail.com>
When we fragment an skb that has already been sent, we need to update
the tx.in_flight for the first skb in the resulting pair ("buff").
Because we were not updating the tx.in_flight, the tx.in_flight value
was inconsistent with the pcount of the "buff" skb (tx.in_flight would
be too high). That meant that if the "buff" skb was lost, then
bbr2_inflight_hi_from_lost_skb() would calculate an inflight_hi value
that is too high. This could result in longer queues and higher packet
loss.
Packetdrill testing verified that without this commit, when the second
half of an skb is SACKed and then later the first half of that skb is
marked lost, the calculated inflight_hi was incorrect.
Effort: net-tcp_bbr
Origin-9xx-SHA1: 385f1ddc610798fab2837f9f372857438b25f874
Origin-9xx-SHA1: a0eb099690af net-tcp_bbr: v2: fix tcp_fragment() tx.in_flight recomputation [prod feb 8 2021; use as a fixup]
Origin-9xx-SHA1: 885503228153ff0c9114e net-tcp_bbr: v2: introduce tcp_skb_tx_in_flight_is_suspicious() helper for warnings
Change-Id: I617f8cab4e9be7a0b8e8d30b047bf8645393354d
Signed-off-by: Juhyung Park <qkrwngud825@gmail.com>
Add a a new ca opts flag TCP_CONG_WANTS_CE_EVENTS that allows a
congestion control module to receive CE events.
Currently congestion control modules have to set the TCP_CONG_NEEDS_ECN
bit in opts flag to receive CE events but this may incur changes in ECN
behavior elsewhere. This patch adds a new bit TCP_CONG_WANTS_CE_EVENTS
that allows congestion control modules to receive CE events
independently of TCP_CONG_NEEDS_ECN.
Effort: net-tcp
Origin-9xx-SHA1: 9f7e14716cde760bc6c67ef8ef7e1ee48501d95b
Change-Id: I2255506985242f376d910c6fd37daabaf4744f24
Signed-off-by: Juhyung Park <qkrwngud825@gmail.com>
Add logic for an experimental TCP connection behavior, enabled with
tp->fast_ack_mode = 1, which disables checking the receive window
before sending an ack in __tcp_ack_snd_check(). If this behavior is
enabled, the data receiver sends an ACK if the amount of data is >
RCV.MSS.
Change-Id: Iaa0a0fd7108221f883137a79d5bfa724f1b096d4
Signed-off-by: Juhyung Park <qkrwngud825@gmail.com>
Before this commit, when there is a packet loss that creates a sequence
hole that is filled by a TLP loss probe, then tcp_process_tlp_ack()
only informs the congestion control (CC) module via a back-to-back entry
and exit of CWR. But some congestion control modules (e.g. BBR) do not
respond to CWR events.
This commit adds a new CA event with which the core TCP stack notifies
the CC module when a loss is repaired by a TLP. This will allow CC
modules that do not use the CWR mechanism to have a custom handler for
such TLP recoveries.
Effort: net-tcp_bbr
Change-Id: Ieba72332b401b329bff5a641d2b2043a3fb8f632
Signed-off-by: Juhyung Park <qkrwngud825@gmail.com>
Introduce is_acking_tlp_retrans_seq into rate_sample. This bool will
export to the CC module the knowledge of whether the current ACK
matched a TLP retransmit.
Note that when this bool is true, we cannot yet tell (in general) whether
this ACK is for the original or the TLP retransmit.
Effort: net-tcp_bbr
Change-Id: I2e6494332167e75efcbdc99bd5c119034e9c39b4
Signed-off-by: Juhyung Park <qkrwngud825@gmail.com>
Define and implement a new per-route feature, RTAX_FEATURE_ECN_LOW.
This feature indicates that the given destination network is a
low-latency ECN environment, meaning both that ECN CE marks are
applied by the network using a low-latency marking threshold and also
that TCP endpoints provide precise per-data-segment ECN feedback in
ACKs (where the ACK ECE flag echoes the received CE status of all
newly-acknowledged data segments). This feature indication can be used
by congestion control algorithms to decide how to interpret ECN
signals over the given destination network.
This feature is appropriate for datacenter-style ECN marking, such as
the ECN marking approach expected by DCTCP or BBR congestion control
modules.
Signed-off-by: David Morley <morleyd@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Tested-by: David Morley <morleyd@google.com>
Change-Id: I6bc06e9c6cb426fbae7243fc71c9a8c18175f5d3
Signed-off-by: Juhyung Park <qkrwngud825@gmail.com>
Analogous to other important ECN information, export TCPI_OPT_ECN_LOW
in tcp_info tcpi_options field.
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Change-Id: I08d8d8c7e8780e6e37df54038ee50301ac5a0320
Signed-off-by: Juhyung Park <qkrwngud825@gmail.com>
For us, it's most helpful to have the round-robin timeslice as low as is
allowed by the scheduler to reduce latency. Since it's limited by the
scheduler tick rate, just set the default to 1 jiffy, which is the
lowest possible value.
Signed-off-by: Sultan Alsawaf <sultan@kerneltoast.com>
Change-Id: I6c9f6bb5bbadf363efb719d3e30b0b073654d688
When a new threshold breaching stall happens after a psi event was
generated and within the window duration, the new event is not
generated because the events are rate-limited to one per window. If
after that no new stall is recorded then the event will not be
generated even after rate-limiting duration has passed. This is
happening because with no new stall, window_update will not be called
even though threshold was previously breached. To fix this, record
threshold breaching occurrence and generate the event once window
duration is passed.
Suggested-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Zhaoyang Huang <zhaoyang.huang@unisoc.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Suren Baghdasaryan <surenb@google.com>
Link: https://lore.kernel.org/r/1643093818-19835-1-git-send-email-huangzhaoyang@gmail.com
(cherry picked from commit e6df4ead85d9da1b07dd40bd4c6d2182f3e210c4)
(cherry picked from commit 007db79713251fd67cc5ce7142942772f6074aca)
(cherry picked from commit 129c4324ce9ea8be9c528629bca72e1e1f80d3fb)
Decay max_newidle_lb_cost only when it has not been updated for a while
and ensure to not decay a recently changed value.
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Link: https://lore.kernel.org/r/20211019123537.17146-4-vincent.guittot@linaro.org
These are used in Android.
Promote these to disable CONFIG_SCHED_DEBUG.
Signed-off-by: Park Ju Hyung <qkrwngud825@gmail.com>
[0ctobot: Adapted for 4.19]
Signed-off-by: Adam W. Willis <return.of.octobot@gmail.com>
Change-Id: I8053176882e155926769939de15da375e7d548a0
[ Upstream commit 7738a7ab9d12c5371ed97114ee2132d4512e9fd5 ]
Add a quirk similar to eeprom_93xx46 to add an extra clock cycle before
reading data from the EEPROM.
The 93Cx6 family of EEPROMs output a "dummy 0 bit" between the writing
of the op-code/address from the host to the EEPROM and the reading of
the actual data from the EEPROM.
More info can be found on page 6 of the AT93C46 datasheet (linked below).
Similar notes are found in other 93xx6 datasheets.
In summary the read operation for a 93Cx6 EEPROM is:
Write to EEPROM: 110[A5-A0] (9 bits)
Read from EEPROM: 0[D15-D0] (17 bits)
Where:
110 is the start bit and READ OpCode
[A5-A0] is the address to read from
0 is a "dummy bit" preceding the actual data
[D15-D0] is the actual data.
Looking at the READ timing diagrams in the 93Cx6 datasheets the dummy
bit should be clocked out on the last address bit clock cycle meaning it
should be discarded naturally.
However, depending on the hardware configuration sometimes this dummy
bit is not discarded. This is the case with Exar PCI UARTs which require
an extra clock cycle between sending the address and reading the data.
Datasheet: https://ww1.microchip.com/downloads/en/DeviceDoc/Atmel-5193-SEEPROM-AT93C46D-Datasheet.pdf
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Parker Newman <pnewman@connecttech.com>
Link: https://lore.kernel.org/r/0f23973efefccd2544705a0480b4ad4c2353e407.1727880931.git.pnewman@connecttech.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 2f552fa280590e61bd3dbe66a7b54b99caa642a4 ]
Extend the address status bit to 4 and introduce the
I3C_ADDR_SLOT_EXT_DESIRED macro to indicate that a device prefers a
specific address. This is generally set by the 'assigned-address' in the
device tree source (dts) file.
┌────┬─────────────┬───┬─────────┬───┐
│S/Sr│ 7'h7E RnW=0 │ACK│ ENTDAA │ T ├────┐
└────┴─────────────┴───┴─────────┴───┘ │
┌─────────────────────────────────────────┘
│ ┌──┬─────────────┬───┬─────────────────┬────────────────┬───┬─────────┐
└─►│Sr│7'h7E RnW=1 │ACK│48bit UID BCR DCR│Assign 7bit Addr│PAR│ ACK/NACK│
└──┴─────────────┴───┴─────────────────┴────────────────┴───┴─────────┘
Some master controllers (such as HCI) need to prepare the entire above
transaction before sending it out to the I3C bus. This means that a 7-bit
dynamic address needs to be allocated before knowing the target device's
UID information.
However, some I3C targets may request specific addresses (called as
"init_dyn_addr"), which is typically specified by the DT-'s
assigned-address property. Lower addresses having higher IBI priority. If
it is available, i3c_bus_get_free_addr() preferably return a free address
that is not in the list of desired addresses (called as "init_dyn_addr").
This allows the device with the "init_dyn_addr" to switch to its
"init_dyn_addr" when it hot-joins the I3C bus. Otherwise, if the
"init_dyn_addr" is already in use by another I3C device, the target device
will not be able to switch to its desired address.
If the previous step fails, fallback returning one of the remaining
unassigned address, regardless of its state in the desired list.
Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: Frank Li <Frank.Li@nxp.com>
Link: https://lore.kernel.org/r/20241021-i3c_dts_assign-v8-2-4098b8bde01e@nxp.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Stable-dep-of: 851bd21cdb55 ("i3c: master: Fix dynamic address leak when 'assigned-address' is present")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 16aed0a6520ba01b7d22c32e193fc1ec674f92d4 ]
Replace the hardcoded value 2, which indicates 2 bits for I3C address
status, with the predefined macro I3C_ADDR_SLOT_STATUS_BITS.
Improve maintainability and extensibility of the code.
Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: Frank Li <Frank.Li@nxp.com>
Link: https://lore.kernel.org/r/20241021-i3c_dts_assign-v8-1-4098b8bde01e@nxp.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Stable-dep-of: 851bd21cdb55 ("i3c: master: Fix dynamic address leak when 'assigned-address' is present")
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit bc73b4186736341ab5cd2c199da82db6e1134e13 upstream.
A bug was found in the find_closest() (find_closest_descending() is also
affected after some testing), where for certain values with small
progressions, the rounding (done by averaging 2 values) causes an
incorrect index to be returned. The rounding issues occur for
progressions of 1, 2 and 3. It goes away when the progression/interval
between two values is 4 or larger.
It's particularly bad for progressions of 1. For example if there's an
array of 'a = { 1, 2, 3 }', using 'find_closest(2, a ...)' would return 0
(the index of '1'), rather than returning 1 (the index of '2'). This
means that for exact values (with a progression of 1), find_closest() will
misbehave and return the index of the value smaller than the one we're
searching for.
For progressions of 2 and 3, the exact values are obtained correctly; but
values aren't approximated correctly (as one would expect). Starting with
progressions of 4, all seems to be good (one gets what one would expect).
While one could argue that 'find_closest()' should not be used for arrays
with progressions of 1 (i.e. '{1, 2, 3, ...}', the macro should still
behave correctly.
The bug was found while testing the 'drivers/iio/adc/ad7606.c',
specifically the oversampling feature.
For reference, the oversampling values are listed as:
static const unsigned int ad7606_oversampling_avail[7] = {
1, 2, 4, 8, 16, 32, 64,
};
When doing:
1. $ echo 1 > /sys/bus/iio/devices/iio\:device0/oversampling_ratio
$ cat /sys/bus/iio/devices/iio\:device0/oversampling_ratio
1 # this is fine
2. $ echo 2 > /sys/bus/iio/devices/iio\:device0/oversampling_ratio
$ cat /sys/bus/iio/devices/iio\:device0/oversampling_ratio
1 # this is wrong; 2 should be returned here
3. $ echo 3 > /sys/bus/iio/devices/iio\:device0/oversampling_ratio
$ cat /sys/bus/iio/devices/iio\:device0/oversampling_ratio
2 # this is fine
4. $ echo 4 > /sys/bus/iio/devices/iio\:device0/oversampling_ratio
$ cat /sys/bus/iio/devices/iio\:device0/oversampling_ratio
4 # this is fine
And from here-on, the values are as correct (one gets what one would
expect.)
While writing a kunit test for this bug, a peculiar issue was found for the
array in the 'drivers/hwmon/ina2xx.c' & 'drivers/iio/adc/ina2xx-adc.c'
drivers. While running the kunit test (for 'ina226_avg_tab' from these
drivers):
* idx = find_closest([-1 to 2], ina226_avg_tab, ARRAY_SIZE(ina226_avg_tab));
This returns idx == 0, so value.
* idx = find_closest(3, ina226_avg_tab, ARRAY_SIZE(ina226_avg_tab));
This returns idx == 0, value 1; and now one could argue whether 3 is
closer to 4 or to 1. This quirk only appears for value '3' in this
array, but it seems to be a another rounding issue.
* And from 4 onwards the 'find_closest'() works fine (one gets what one
would expect).
This change reworks the find_closest() macros to also check the difference
between the left and right elements when 'x'. If the distance to the right
is smaller (than the distance to the left), the index is incremented by 1.
This also makes redundant the need for using the DIV_ROUND_CLOSEST() macro.
In order to accommodate for any mix of negative + positive values, the
internal variables '__fc_x', '__fc_mid_x', '__fc_left' & '__fc_right' are
forced to 'long' type. This also addresses any potential bugs/issues with
'x' being of an unsigned type. In those situations any comparison between
signed & unsigned would be promoted to a comparison between 2 unsigned
numbers; this is especially annoying when '__fc_left' & '__fc_right'
underflow.
The find_closest_descending() macro was also reworked and duplicated from
the find_closest(), and it is being iterated in reverse. The main reason
for this is to get the same indices as 'find_closest()' (but in reverse).
The comparison for '__fc_right < __fc_left' favors going the array in
ascending order.
For example for array '{ 1024, 512, 256, 128, 64, 16, 4, 1 }' and x = 3, we
get:
__fc_mid_x = 2
__fc_left = -1
__fc_right = -2
Then '__fc_right < __fc_left' evaluates to true and '__fc_i++' becomes 7
which is not quite incorrect, but 3 is closer to 4 than to 1.
This change has been validated with the kunit from the next patch.
Link: https://lkml.kernel.org/r/20241105145406.554365-1-aardelean@baylibre.com
Fixes: 95d119528b0b ("util_macros.h: add find_closest() macro")
Signed-off-by: Alexandru Ardelean <aardelean@baylibre.com>
Cc: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 2790a624d43084de590884934969e19c7a82316a ]
The socket's SOCKWQ_ASYNC_NOSPACE can be cleared by various actors in
the socket layer, so replace it with our own flag in the transport
sock_state field.
Reported-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Stable-dep-of: 4db9ad82a6c8 ("sunrpc: clear XPRT_SOCK_UPD_TIMEOUT when reset transport")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 71d3d0ebc894294ef9454e45a3ac2e9ba60b3351 ]
There are now tools in the refcount library that allow us to convert the
client shutdown code.
Reported-by: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Stable-dep-of: 4db9ad82a6c8 ("sunrpc: clear XPRT_SOCK_UPD_TIMEOUT when reset transport")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 46fd48ab3ea3eb3bb215684bd66ea3d260b091a9 ]
The underlying limit is defined as an unsigned int, so return that from
bdev_io_min as well.
Fixes: ac481c20ef8f ("block: Topology ioctls")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Link: https://lore.kernel.org/r/20241119072602.1059488-1-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
