The tool pp_alloc_fail.py tested error recovery by injecting errors
into the function page_pool_alloc_pages(). The page pool allocation
function page_pool_dev_alloc() does not end up calling
page_pool_alloc_pages(). page_pool_alloc_netmems() seems to be the
function that is called by all of the page pool alloc functions in
the API, so move error injection to that function instead.
Signed-off-by: John Daley <johndale@cisco.com>
Link: https://patch.msgid.link/20250115181312.3544-2-johndale@cisco.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Store rtm->rtm_tos in a dscp_t variable, which can then be used for
setting fl4.flowi4_tos and also be passed as parameter of
ip_route_input_rcu().
The .flowi4_tos field is going to be converted to dscp_t to ensure ECN
bits aren't erroneously taken into account during route lookups. Having
a dscp_t variable available will simplify that conversion, as we'll
just have to drop the inet_dscp_to_dsfield() call.
Note that we can't just convert rtm->rtm_tos to dscp_t because this
structure is exported to user space.
Signed-off-by: Guillaume Nault <gnault@redhat.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/7bc1c7dc47ad1393569095d334521fae59af5bc7.1736944951.git.gnault@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Pull networking fixes from Paolo Abeni:
"Notably this includes fixes for a few regressions spotted very
recently. No known outstanding ones.
Current release - regressions:
- core: avoid CFI problems with sock priv helpers
- xsk: bring back busy polling support
- netpoll: ensure skb_pool list is always initialized
Current release - new code bugs:
- core: make page_pool_ref_netmem work with net iovs
- ipv4: route: fix drop reason being overridden in
ip_route_input_slow
- udp: make rehash4 independent in udp_lib_rehash()
Previous releases - regressions:
- bpf: fix bpf_sk_select_reuseport() memory leak
- openvswitch: fix lockup on tx to unregistering netdev with carrier
- mptcp: be sure to send ack when mptcp-level window re-opens
- eth:
- bnxt: always recalculate features after XDP clearing, fix
null-deref
- mlx5: fix sub-function add port error handling
- fec: handle page_pool_dev_alloc_pages error
Previous releases - always broken:
- vsock: some fixes due to transport de-assignment
- eth:
- ice: fix E825 initialization
- mlx5e: fix inversion dependency warning while enabling IPsec
tunnel
- gtp: destroy device along with udp socket's netns dismantle.
- xilinx: axienet: Fix IRQ coalescing packet count overflow"
* tag 'net-6.13-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (44 commits)
netdev: avoid CFI problems with sock priv helpers
net/mlx5e: Always start IPsec sequence number from 1
net/mlx5e: Rely on reqid in IPsec tunnel mode
net/mlx5e: Fix inversion dependency warning while enabling IPsec tunnel
net/mlx5: Clear port select structure when fail to create
net/mlx5: SF, Fix add port error handling
net/mlx5: Fix a lockdep warning as part of the write combining test
net/mlx5: Fix RDMA TX steering prio
net: make page_pool_ref_netmem work with net iovs
net: ethernet: xgbe: re-add aneg to supported features in PHY quirks
net: pcs: xpcs: actively unset DW_VR_MII_DIG_CTRL1_2G5_EN for 1G SGMII
net: pcs: xpcs: fix DW_VR_MII_DIG_CTRL1_2G5_EN bit being set for 1G SGMII w/o inband
selftests: net: Adapt ethtool mq tests to fix in qdisc graft
net: fec: handle page_pool_dev_alloc_pages error
net: netpoll: ensure skb_pool list is always initialized
net: xilinx: axienet: Fix IRQ coalescing packet count overflow
nfp: bpf: prevent integer overflow in nfp_bpf_event_output()
selftests: mptcp: avoid spurious errors on disconnect
mptcp: fix spurious wake-up on under memory pressure
mptcp: be sure to send ack when mptcp-level window re-opens
...
Pull power management fixes from Rafael Wysocki:
"Update the documentation of cpuidle governors that does not match the
code any more after previous functional changes (Rafael Wysocki) and
fix up the cpufreq Kconfig file broken inadvertently by a previous
update (Viresh Kumar)"
* tag 'pm-6.13-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
cpufreq: Move endif to the end of Kconfig file
cpuidle: teo: Update documentation after previous changes
cpuidle: menu: Update documentation after previous changes
Pull ACPI fix from Rafael Wysocki:
"Prevent acpi_video_device_EDID() from returning a pointer to a memory
region that should not be passed to kfree() which causes one of its
users to crash randomly on attempts to free it (Chris Bainbridge)"
* tag 'acpi-6.13-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
ACPI: video: Fix random crashes due to bad kfree()
Pull btrfs fix from David Sterba:
- handle d_path() errors when canonicalizing device mapper paths during
device scan
* tag 'for-6.13-rc7-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: add the missing error handling inside get_canonical_dev_path
Merge a cpufreq fix for 6.13:
- Fix cpufreq Kconfig breakage after previous changes (Viresh Kumar).
* pm-cpufreq:
cpufreq: Move endif to the end of Kconfig file
According to RFC4303, section "3.3.3. Sequence Number Generation",
the first packet sent using a given SA will contain a sequence
number of 1.
This is applicable to both ESN and non-ESN mode, which was not covered
in commit mentioned in Fixes line.
Fixes: 3d42c8cc67 ("net/mlx5e: Ensure that IPsec sequence packet number starts from 1")
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
All packet offloads SAs have reqid in it to make sure they have
corresponding policy. While it is not strictly needed for transparent
mode, it is extremely important in tunnel mode. In that mode, policy and
SAs have different match criteria.
Policy catches the whole subnet addresses, and SA catches the tunnel gateways
addresses. The source address of such tunnel is not known during egress packet
traversal in flow steering as it is added only after successful encryption.
As reqid is required for packet offload and it is unique for every SA,
we can safely rely on it only.
The output below shows the configured egress policy and SA by strongswan:
[leonro@vm ~]$ sudo ip x s
src 192.169.101.2 dst 192.169.101.1
proto esp spi 0xc88b7652 reqid 1 mode tunnel
replay-window 0 flag af-unspec esn
aead rfc4106(gcm(aes)) 0xe406a01083986e14d116488549094710e9c57bc6 128
anti-replay esn context:
seq-hi 0x0, seq 0x0, oseq-hi 0x0, oseq 0x0
replay_window 1, bitmap-length 1
00000000
crypto offload parameters: dev eth2 dir out mode packet
[leonro@064 ~]$ sudo ip x p
src 192.170.0.0/16 dst 192.170.0.0/16
dir out priority 383615 ptype main
tmpl src 192.169.101.2 dst 192.169.101.1
proto esp spi 0xc88b7652 reqid 1 mode tunnel
crypto offload parameters: dev eth2 mode packet
Fixes: b3beba1fb4 ("net/mlx5e: Allow policies with reqid 0, to support IKE policy holes")
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
If failed to add SF, error handling doesn't delete the SF from the
SF table. But the hw resources are deleted. So when unload driver,
hw resources will be deleted again. Firmware will report syndrome
0x68def3 which means "SF is not allocated can not deallocate".
Fix it by delete SF from SF table if failed to add SF.
Fixes: 2597ee190b ("net/mlx5: Call mlx5_sf_id_erase() once in mlx5_sf_dealloc()")
Signed-off-by: Chris Mi <cmi@nvidia.com>
Reviewed-by: Shay Drori <shayd@nvidia.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
User added steering rules at RDMA_TX were being added to the first prio,
which is the counters prio.
Fix that so that they are correctly added to the BYPASS_PRIO instead.
Fixes: 24670b1a31 ("net/mlx5: Add support for RDMA TX steering")
Signed-off-by: Patrisious Haddad <phaddad@nvidia.com>
Reviewed-by: Mark Bloch <mbloch@nvidia.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Furong Xu says:
====================
net: stmmac: RX performance improvement
This series improves RX performance a lot, ~40% TCP RX throughput boost
has been observed with DWXGMAC CORE 3.20a running on Cortex-A65 CPUs:
from 2.18 Gbits/sec increased to 3.06 Gbits/sec.
====================
Link: https://patch.msgid.link/cover.1736910454.git.0x1207@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
The size of DMA descriptors is 32 bytes at most.
net_prefetch() for received frames, and keep prefetch() for descriptors.
This patch brings ~4.8% driver performance improvement in a TCP RX
throughput test with iPerf tool on a single isolated Cortex-A65 CPU
core, 2.92 Gbits/sec increased to 3.06 Gbits/sec.
Suggested-by: Joe Damato <jdamato@fastly.com>
Signed-off-by: Furong Xu <0x1207@gmail.com>
Reviewed-by: Yanteng Si <si.yanteng@linux.dev>
Reviewed-by: Larysa Zaremba <larysa.zaremba@intel.com>
Reviewed-by: Joe Damato <jdamato@fastly.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Current code prefetches cache lines for the received frame first, and
then dma_sync_single_for_cpu() against this frame, this is wrong.
Cache prefetch should be triggered after dma_sync_single_for_cpu().
This patch brings ~2.8% driver performance improvement in a TCP RX
throughput test with iPerf tool on a single isolated Cortex-A65 CPU
core, 2.84 Gbits/sec increased to 2.92 Gbits/sec.
Signed-off-by: Furong Xu <0x1207@gmail.com>
Reviewed-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Reviewed-by: Yanteng Si <si.yanteng@linux.dev>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
DMA engine will always write no more than dma_buf_sz bytes of a received
frame into a page buffer, the remaining spaces are unused or used by CPU
exclusively.
Setting page_pool_params.max_len to almost the full size of page(s) helps
nothing more, but wastes more CPU cycles on cache maintenance.
For a standard MTU of 1500, then dma_buf_sz is assigned to 1536, and this
patch brings ~16.9% driver performance improvement in a TCP RX
throughput test with iPerf tool on a single isolated Cortex-A65 CPU
core, from 2.43 Gbits/sec increased to 2.84 Gbits/sec.
Signed-off-by: Furong Xu <0x1207@gmail.com>
Reviewed-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Reviewed-by: Yanteng Si <si.yanteng@linux.dev>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Avoid memcpy in non-XDP RX path by marking all allocated SKBs to
be recycled in the upper network stack.
This patch brings ~11.5% driver performance improvement in a TCP RX
throughput test with iPerf tool on a single isolated Cortex-A65 CPU
core, from 2.18 Gbits/sec increased to 2.43 Gbits/sec.
Signed-off-by: Furong Xu <0x1207@gmail.com>
Reviewed-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Reviewed-by: Larysa Zaremba <larysa.zaremba@intel.com>
Reviewed-by: Yanteng Si <si.yanteng@linux.dev>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Tariq Toukan says:
====================
net/mlx5e: CT: Add support for hardware steering
This series start with one more HWS patch by Yevgeny, followed by
patches that add support for connection tracking in hardware steering
mode. It consists of:
- patch #2 hooks up the CT ops for the new mode in the right places.
- patch #3 moves a function into a common file, so it can be reused.
- patch #4 uses the HWS API to implement connection tracking.
The main advantage of hardware steering compared to software steering is
vastly improved performance when adding/removing/updating rules. Using
the T-Rex traffic generator to initiate multi-million UDP flows per
second, a kernel running with these patches was able to offload ~600K
unique UDP flows per second, a number around ~7x larger than software
steering was able to achieve on the same hardware (256-thread AMD EPYC,
512 GB RAM, ConnectX 7 b2b).
====================
Link: https://patch.msgid.link/20250114130646.1937192-1-tariqt@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This is modeled similar to how software steering works:
- a reference-counted matcher is maintained for each
combination of nat/no_nat x ipv4/ipv6 x tcp/udp/gre.
- adding a rule involves finding+referencing or creating a corresponding
matcher, then actually adding a rule.
- updating rules is implemented using the bwc_rule update API, which can
change a rule's actions without touching the match value.
By using a T-Rex traffic generator to initiate multi-million UDP flows
per second, a kernel running with these patches on the RX side was able
to offload ~600K flows per second, which is about ~7x larger than what
software steering could do on the same hardware (256-thread AMD EPYC,
512 GB RAM, ConnectX-7 b2b).
Signed-off-by: Cosmin Ratiu <cratiu@nvidia.com>
Reviewed-by: Jianbo Liu <jianbol@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Link: https://patch.msgid.link/20250114130646.1937192-5-tariqt@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This function checks whether a flow_rule has the right flow dissector
keys and masks used for a connection tracking flow offload. It is
currently used locally by the tc_ct smfs module, but is about to be used
from another place, so this commit moves it to a better place, renames
it to mlx5e_tc_ct_is_valid_flow_rule and drops the unused fs argument.
Signed-off-by: Cosmin Ratiu <cratiu@nvidia.com>
Reviewed-by: Jianbo Liu <jianbol@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Link: https://patch.msgid.link/20250114130646.1937192-4-tariqt@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Connection tracking can offload tuple matches to the NIC either via
firmware commands (when the steering mode is dmfs or offload support is
disabled due to eswitch being set to legacy) or via software-managed
flow steering (smfs).
This commit adds stub operations for a third mode, hardware-managed flow
steering. This is enabled when both CONFIG_MLX5_TC_CT and
CONFIG_MLX5_HW_STEERING are enabled.
Signed-off-by: Cosmin Ratiu <cratiu@nvidia.com>
Reviewed-by: Jianbo Liu <jianbol@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Link: https://patch.msgid.link/20250114130646.1937192-3-tariqt@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When checking if the matcher size can be increased, check both
match and action RTCs. Also, consider the increasing step - check
that it won't cause the new matcher size to become unsupported.
Additionally, since we're using '+ 1' for action RTC size yet
again, define it as macro and use in all the required places.
Signed-off-by: Yevgeny Kliteynik <kliteyn@nvidia.com>
Reviewed-by: Mark Bloch <mbloch@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Link: https://patch.msgid.link/20250114130646.1937192-2-tariqt@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
One synchronize_net() call is currently done while holding RTNL.
This is source of RTNL contention in workloads adding and deleting
many network namespaces per second, because synchronize_rcu()
and synchronize_rcu_expedited() can use 60+ ms in some cases.
For cleanup_net() use, temporarily release RTNL
while calling the last synchronize_net().
This should be safe, because devices are no longer visible
to other threads after unlist_netdevice() call
and setting dev->reg_state to NETREG_UNREGISTERING.
In any case, the new netdev_lock() / netdev_unlock()
infrastructure that we are adding should allow
to fix potential issues, with a combination
of a per-device mutex and dev->reg_state awareness.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Jesse Brandeburg <jbrandeburg@cloudflare.com>
Link: https://patch.msgid.link/20250114205531.967841-6-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Two synchronize_net() calls are currently done while holding RTNL.
This is source of RTNL contention in workloads adding and deleting
many network namespaces per second, because synchronize_rcu()
and synchronize_rcu_expedited() can use 60+ ms in some cases.
For cleanup_net() use, temporarily release RTNL
while calling the last synchronize_net().
This should be safe, because devices are no longer visible
to other threads at this point.
In any case, the new netdev_lock() / netdev_unlock()
infrastructure that we are adding should allow
to fix potential issues, with a combination
of a per-device mutex and dev->reg_state awareness.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Jesse Brandeburg <jbrandeburg@cloudflare.com>
Link: https://patch.msgid.link/20250114205531.967841-5-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
flush_all_backlogs() is called from unregister_netdevice_many_notify()
as part of netdevice dismantles.
This is currently called under RTNL, and can last up to 50 ms
on busy hosts.
There is no reason to hold RTNL at this stage, if our caller
is cleanup_net() : netns are no more visible, devices
are in NETREG_UNREGISTERING state and no other thread
could mess our state while RTNL is temporarily released.
In order to provide isolation, this patch provides a separate
'net_todo_list' for cleanup_net().
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Jesse Brandeburg <jbrandeburg@cloudflare.com>
Link: https://patch.msgid.link/20250114205531.967841-4-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
flush_all_backlogs() uses per-cpu and static data to hold its
temporary data, on the assumption it is called under RTNL
protection.
Following patch in the series will break this assumption.
Use instead a dynamically allocated piece of memory.
In the unlikely case the allocation fails,
use a boot-time allocated memory.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Jesse Brandeburg <jbrandeburg@cloudflare.com>
Link: https://patch.msgid.link/20250114205531.967841-3-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Protect the following members of netdev and napi by netdev_lock:
- defer_hard_irqs,
- gro_flush_timeout,
- irq_suspend_timeout.
The first two are written via sysfs (which this patch switches
to new lock), and netdev genl which holds both netdev and rtnl locks.
irq_suspend_timeout is only written by netdev genl.
Reviewed-by: Joe Damato <jdamato@fastly.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20250115035319.559603-11-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Now that NAPI instances can't come and go without holding
netdev->lock we can trivially switch from rtnl_lock() to
netdev_lock() for setting netdev->threaded via sysfs.
Note that since we do not lock netdev_lock around sysfs
calls in the core we don't have to "trylock" like we do
with rtnl_lock.
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20250115035319.559603-9-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
In prep for dropping rtnl_lock, start locking netdev->lock in netlink
genl ops. We need to be using netdev->up instead of flags & IFF_UP.
We can remove the RCU lock protection for the NAPI since NAPI list
is protected by netdev->lock already.
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20250115035319.559603-8-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Wrap napi_enable() / napi_disable() with netdev_lock().
Provide the "already locked" flavor of the API.
iavf needs the usual adjustment. A number of drivers call
napi_enable() under a spin lock, so they have to be modified
to take netdev_lock() first, then spin lock then call
napi_enable_locked().
Protecting napi_enable() implies that napi->napi_id is protected
by netdev_lock().
Acked-by: Francois Romieu <romieu@fr.zoreil.com> # via-velocity
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20250115035319.559603-7-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Hold netdev->lock when NAPIs are getting added or removed.
This will allow safe access to NAPI instances of a net_device
without rtnl_lock.
Create a family of helpers which assume the lock is already taken.
Switch iavf to them, as it makes extensive use of netdev->lock,
already.
Reviewed-by: Joe Damato <jdamato@fastly.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20250115035319.559603-6-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Some uAPI (netdev netlink) hide net_device's sub-objects while
the interface is down to ensure uniform behavior across drivers.
To remove the rtnl_lock dependency from those uAPIs we need a way
to safely tell if the device is down or up.
Add an indication of whether device is open or closed, protected
by netdev->lock. The semantics are the same as IFF_UP, but taking
netdev_lock around every write to ->flags would be a lot of code
churn.
We don't want to blanket the entire open / close path by netdev_lock,
because it will prevent us from applying it to specific structures -
core helpers won't be able to take that lock from any function
called by the drivers on open/close paths.
So the state of the flag is "pessimistic", as in it may report false
negatives, but never false positives.
Reviewed-by: Joe Damato <jdamato@fastly.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20250115035319.559603-5-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Add helpers for accessing netdevs under netdev_lock().
There's some careful handling needed to find the device and lock it
safely, without it getting unregistered, and without taking rtnl_lock
(the latter being the whole point of the new locking, after all).
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20250115035319.559603-4-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Protect writes to netdev->reg_state with netdev_lock().
From now on holding netdev_lock() is sufficient to prevent
the net_device from getting unregistered, so code which
wants to hold just a single netdev around no longer needs
to hold rtnl_lock.
We do not protect the NETREG_UNREGISTERED -> NETREG_RELEASED
transition. We'd need to move mutex_destroy(netdev->lock)
to .release, but the real reason is that trying to stop
the unregistration process mid-way would be unsafe / crazy.
Taking references on such devices is not safe, either.
So the intended semantics are to lock REGISTERED devices.
Reviewed-by: Joe Damato <jdamato@fastly.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20250115035319.559603-3-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Currently, the driver is seriously broken with respect to the
hibernation (S4): after image restore the device is back into
IPC_MEM_EXEC_STAGE_BOOT (which AFAIK means bootloader stage) and needs
full re-launch of the rest of its firmware, but the driver restore
handler treats the device as merely sleeping and just sends it a
wake-up command.
This wake-up command times out but device nodes (/dev/wwan*) remain
accessible.
However attempting to use them causes the bootloader to crash and
enter IPC_MEM_EXEC_STAGE_CD_READY stage (which apparently means "a crash
dump is ready").
It seems that the device cannot be re-initialized from this crashed
stage without toggling some reset pin (on my test platform that's
apparently what the device _RST ACPI method does).
While it would theoretically be possible to rewrite the driver to tear
down the whole MUX / IPC layers on hibernation (so the bootloader does
not crash from improper access) and then re-launch the device on
restore this would require significant refactoring of the driver
(believe me, I've tried), since there are quite a few assumptions
hard-coded in the driver about the device never being partially
de-initialized (like channels other than devlink cannot be closed,
for example).
Probably this would also need some programming guide for this hardware.
Considering that the driver seems orphaned [1] and other people are
hitting this issue too [2] fix it by simply unbinding the PCI driver
before hibernation and re-binding it after restore, much like
USB_QUIRK_RESET_RESUME does for USB devices that exhibit a similar
problem.
Tested on XMM7360 in HP EliteBook 855 G7 both with s2idle (which uses
the existing suspend / resume handlers) and S4 (which uses the new code).
[1]: https://lore.kernel.org/all/c248f0b4-2114-4c61-905f-466a786bdebb@leemhuis.info/
[2]:
https://github.com/xmm7360/xmm7360-pci/issues/211#issuecomment-1804139413
Reviewed-by: Sergey Ryazanov <ryazanov.s.a@gmail.com>
Signed-off-by: Maciej S. Szmigiero <mail@maciej.szmigiero.name>
Link: https://patch.msgid.link/e60287ebdb0ab54c4075071b72568a40a75d0205.1736372610.git.mail@maciej.szmigiero.name
Signed-off-by: Jakub Kicinski <kuba@kernel.org>