| Age | Commit message (Collapse) | Author |
|---|
|
update_userdata() takes target_list_lock to swap nt->userdata and
nt->userdata_length, then frees the old buffer. Since commit
7eab73b18630 ("netconsole: convert to NBCON console infrastructure")
that lock is also the console's device_lock, so writing a userdata value
from configfs serialises against the printk core emitting messages.
The buffer is immutable once published, which is what RCU is for. Move
the string and its length into a single netcons_userdata object and
publish it with rcu_replace_pointer(), freeing the old one with
kfree_rcu().
New userdata design:
0) Unify the userdata fields into a struct netcons_userdata
1) update_userdata() no longer needs target_list_lock.
2) writers stay serialised by dynamic_netconsole_mutex.
3) reading userdata needs an RCU read lock.
No functional change intended.
Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Gustavo Luiz Duarte <gustavold@gmail.com>
Link: https://patch.msgid.link/20260810-netcons-userdata-rcu-v3-1-f65557f769ce@debian.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
|
|
netpoll_wait_carrier() waits for the egress device carrier during
netconsole setup. Its only caller, netcons_netpoll_setup(), already
lives in netconsole. Move the function into drivers/net/netconsole.c,
drop EXPORT_SYMBOL_GPL() and remove the prototype from <linux/netpoll.h>.
Rename it to netcons_wait_carrier() for the netcons_ prefix. It now reads
the timeout through netpoll_get_carrier_timeout(), since carrier_timeout
stays in netpoll to keep the netpoll.carrier_timeout parameter.
Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Gustavo Luiz Duarte <gustavold@gmail.com>
Link: https://patch.msgid.link/20260724-netconsole_move_more_final-v1-9-a5f7691db81c@debian.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
|
|
With netpoll_setup() and the packet-building path now living in
netconsole, local_ip, remote_ip and ipv6 in struct netpoll are read
and written only by netconsole. No other netpoll user touches them.
Move the three fields into netconsole_target and switch the packet
builders and setup helpers to take the target instead of the netpoll
handle. struct netpoll is left holding only the device-binding state
that the shared netpoll transport needs.
Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Gustavo Luiz Duarte <gustavold@gmail.com>
Link: https://patch.msgid.link/20260724-netconsole_move_more_final-v1-8-a5f7691db81c@debian.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
|
|
move egress_dev() from netpoll to netconsole, and append netcons_
prefix.
Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Gustavo Luiz Duarte <gustavold@gmail.com>
Link: https://patch.msgid.link/20260724-netconsole_move_more_final-v1-7-a5f7691db81c@debian.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
|
|
Move netpoll_take_ipv6() to netconsole, and add netcons_ prefix.
Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Gustavo Luiz Duarte <gustavold@gmail.com>
Link: https://patch.msgid.link/20260724-netconsole_move_more_final-v1-6-a5f7691db81c@debian.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
|
|
Move netpoll_take_ipv4() to netconsole, which is the only user. Rename
it to netcons_take_ipv4() for the netcons_ prefix. The body is
unchanged.
Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Gustavo Luiz Duarte <gustavold@gmail.com>
Link: https://patch.msgid.link/20260724-netconsole_move_more_final-v1-5-a5f7691db81c@debian.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
|
|
Move netpoll_local_ip_unset() from netpoll to netconsole and rename it
to netcons_local_ip_unset();
The body is otherwise unchanged, only the comment's setup-function
reference is updated.
Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Gustavo Luiz Duarte <gustavold@gmail.com>
Link: https://patch.msgid.link/20260724-netconsole_move_more_final-v1-4-a5f7691db81c@debian.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
|
|
netpoll_setup() is only used by netconsole. All the other users use
__netpoll_setup().
Move netpoll_setup() to netconsole, and rename it to
netcons_netpoll_setup().
Pure code motion: the body is unchanged.
Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Gustavo Luiz Duarte <gustavold@gmail.com>
Link: https://patch.msgid.link/20260724-netconsole_move_more_final-v1-3-a5f7691db81c@debian.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
|
|
Alice Mikityanska says:
====================
BIG TCP for UDP tunnels
This series is a follow-up to "BIG TCP without HBH in IPv6", and it adds
support for BIG TCP IPv4/IPv6 workloads in vxlan and geneve. Now that
IPv6 BIG TCP doesn't require stripping the HBH in all various
combinations in tunneled traffic, adding BIG TCP becomes feasible.
Patch 01 adds accessors for the length field in the UDP header, as
suggested by Paolo in review. The usage of udp_set_len is then added in
the following patches that start using length=0 in BIG TCP UDP packets.
Patches 02-04 close the gaps that prevent BIG TCP packets from going
through UDP tunnel code.
Patch 05 validates packets in udp_gro_receive to exclude packets with
length=0 from GRO aggregation.
Patch 06 is for proper formatting in tcpdump (set UDP len to 0 rather
than a trimmed value on overflow).
Patches 07-08 bump up tso_max_size for VXLAN and GENEVE.
Patch 09 adds selftests.
====================$
Link: https://patch.msgid.link/20260710134242.216538-1-alice.kernel@fastmail.im
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
|
|
Since BIG TCP for UDP tunnels will start using len=0 in the UDP header
as an indicator of a GSO packet bigger than 65535 bytes, this commit
introduces the following getter and setters to use tree-wide, in order
to explicitly mark places where len=0 may be expected, and handle them
properly:
1. udp_set_len() sets uh->len to its real value if it's not bigger than
65535, and to 0 otherwise: to be used in GSO context with aggregated
packets.
2. udp_set_len_short() is to be used when the length is known to fit 16
bits. It WARNs when the caller tries to assign a bigger value if
CONFIG_DEBUG_NET=y.
3. udp_get_len_short() returns len in host byte order: to be used on the
RX side to deal with non-aggregated packets, or to access the raw value
of the len field.
4. udp_get_len() decodes uh->len set by udp_set_len(). It checks whether
the packet is GSO to guard from malformed packets.
At the moment udp_set_len() is not used, a following commit will start
using it after enabling len>65535 for GSO.
Raw uh->len (in network byte order) is still accessed in a few places
for checksum calculation purposes, and to decode len=0 in udpv6_rcv for
jumbograms. udp_rcv and udpv6_rcv will be addressed by the commit that
starts using udp_set_len() to set UDP len=0 for BIG TCP packets in UDP
tunnels.
Signed-off-by: Alice Mikityanska <alice@isovalent.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Acked-by: Jason A. Donenfeld <Jason@zx2c4.com>
Link: https://patch.msgid.link/20260710134242.216538-2-alice.kernel@fastmail.im
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
|
|
These two fields back the fallback skb pool that find_skb() uses.
Every helper that touches them lives in netconsole now (refill_skbs,
refill_skbs_work_handler, netconsole_skb_pool_init,
netconsole_skb_pool_flush, find_skb, netcons_skb_pop), so the data
can move alongside its only consumer.
Add skb_pool and refill_wq to struct netconsole_target, drop them
from struct netpoll.
This will save 48-bytes for every netpoll user instance (except
netconsole that will have it in netconsole target struct).
Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20260710-netconsole_move_more-v3-7-6f63f76b28bc@debian.org
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
|
|
The destination ethernet address is netconsole configuration: no other
netpoll user (bonding, team, vlan, bridge, macvlan, dsa) references
np->remote_mac, only netconsole's ethernet framing and its
configfs/cmdline interface do.
Move it into struct netconsole_target and convert push_eth() to take the
netconsole_target; netconsole_print_banner() and
netconsole_parser_cmdline() already take it. The configfs show/store
handlers and alloc_and_init() reach the field directly.
No functional change; the remote_mac sysfs attribute is unchanged.
Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20260710-netconsole_move_more-v3-9-6f63f76b28bc@debian.org
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
|
|
skb_pool_flush() has no callers left in net/core/netpoll.c after
netconsole took over the pool lifecycle. Inline its body into
netconsole_skb_pool_flush() (the only caller) and drop the function
and its export from netpoll. The prototype goes from
<linux/netpoll.h>.
Pure code motion: cancel_work_sync() + skb_queue_purge_reason()
semantics are unchanged.
Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20260710-netconsole_move_more-v3-6-6f63f76b28bc@debian.org
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
|
|
netconsole_target
The source and destination UDP ports live in struct netpoll but are
netconsole configuration. No other netpoll user (bonding, team, vlan,
bridge, macvlan, dsa) touches np->local_port or np->remote_port; they
only use the netpoll TX/forwarding path. Only netconsole's UDP framing
and its configfs/cmdline interface read these fields.
Move both into struct netconsole_target and convert the three helpers
that read them - push_udp(), netconsole_print_banner() and
netconsole_parser_cmdline() - to take the netconsole_target. The
configfs show/store handlers already have the target in hand.
No functional change; the local_port / remote_port sysfs attributes are
unchanged.
Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20260710-netconsole_move_more-v3-8-6f63f76b28bc@debian.org
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
|
|
refill_skbs() is now only called from netconsole (directly via
netconsole_skb_pool_init() and indirectly via the just-moved
refill_skbs_work_handler()), and the MAX_UDP_CHUNK / MAX_SKBS /
MAX_SKB_SIZE macros are private to it. Move them all into
drivers/net/netconsole.c.
MAX_UDP_CHUNK and MAX_SKB_SIZE were promoted to <linux/netpoll.h>
by commit 6c537b845c99 ("netconsole: do not dequeue pooled skbs that
cannot satisfy len") so find_skb() could detect oversized requests
against the same value refill_skbs() used. With both functions now
local to netconsole, the shared definition no longer needs to live
in the header.
Pure code motion: bodies and pool sizing semantics are unchanged.
Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20260710-netconsole_move_more-v3-5-6f63f76b28bc@debian.org
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
|
|
The work handler is wired via INIT_WORK() in
netconsole_skb_pool_init() and has no other callers since the
previous patch took the skb pool lifecycle out of __netpoll_setup().
Move the function body into drivers/net/netconsole.c as a
file-static helper, drop EXPORT_SYMBOL_GPL() and remove the
prototype from <linux/netpoll.h>.
Pure code motion: the body is unchanged and still calls the
exported refill_skbs() in net/core/netpoll.c.
Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20260710-netconsole_move_more-v3-4-6f63f76b28bc@debian.org
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
|
|
The fallback skb pool fronted by find_skb() is netconsole's only client:
every other netpoll goes through __netpoll_setup() / netpoll_send_skb()
without ever touching np->skb_pool.
Today __netpoll_setup() and __netpoll_cleanup() create and destroy the
pool for everyone, paying ~48 KB of pre-allocated skbs per netpoll
instance that only netconsole uses, what a waste!
Move the responsibility to netconsole. __netpoll_setup() did this under
the RTNL, but netconsole enables targets from enabled_store() /
alloc_param_target() without it, while the teardown path flushes the pool
(cancel_work_sync() + skb_queue_purge()) under the RTNL from
netconsole_process_cleanups_core(). Initialising the queue head and the
refill work on every enable would therefore race that flush.
They only need initialising once: after a flush the queue head is left
valid and empty and cancel_work_sync() leaves the work re-armable. Set
them up in alloc_and_init(), while the target is not yet reachable, and
let the enable paths only refill the pool via refill_skbs(), which
serialises with the flush through skb_pool.lock. See discussions in [1]
Link: https://lore.kernel.org/all/alDMvD5S7TZnoD_V@gmail.com/ [1]
Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20260710-netconsole_move_more-v3-3-6f63f76b28bc@debian.org
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
|
|
drop_netconsole_target() might eventually tear down a target that
netconsole_netdev_event() had moved to target_cleanup_list but that
netconsole_process_cleanups_core() had not processed yet.
Always cleanup devices that eventually have a device attached to the
target, independent of the state.
Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20260710-netconsole_move_more-v3-1-6f63f76b28bc@debian.org
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
|
|
find_skb() allocates the skb with GFP_ATOMIC as a best-effort attempt:
on failure it falls back to the preallocated skb pool and, failing that,
polls the device and retries. The allocation failing is therefore an
expected and fully handled condition, but without __GFP_NOWARN the page
allocator still emits a warn_alloc() splat with a full stack trace on
every miss, which then consumes the whole SKB pool, that would be useful
printing the real issue rather than the memory failure.
Pass __GFP_NOWARN so the best-effort allocation stays quiet and lets the
existing fallback path do its job.
Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20260629-netpoll_no_warn-v1-1-f380f0b2cd0c@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
|
|
nt->buf is exactly MAX_PRINT_CHUNK bytes, but scnprintf() reserves one
byte for its NUL terminator, so a non-fragmented payload of exactly
MAX_PRINT_CHUNK loses its last byte (emitted as a stray NUL in the
release path). Grow nt->buf to MAX_PRINT_CHUNK + 1 and bound the
scnprintf() calls with sizeof(nt->buf); the transmitted length stays
capped at MAX_PRINT_CHUNK.
Alternatively, nt->buf could be left at MAX_PRINT_CHUNK and the NUL byte
reserved by routing exactly-MAX_PRINT_CHUNK payloads to fragmentation
('len < MAX_PRINT_CHUNK'), at the cost of fragmenting those messages.
But it would look less sane, thus the current approach.
Fixes: c62c0a17f9b7 ("netconsole: Append kernel version to message")
Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20260616-max_print_chunk-v1-1-8dc125d67083@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
|
|
When process_resume_target() catches a device that was unregistered
while the target was off target_list, it calls do_netpoll_cleanup() to
release the reference but leaves the cached np.dev_name in place. The
other cleanup path, netconsole_process_cleanups_core(), already wipes
dev_name for MAC-bound targets because the name was only a cache of the
device that last carried the MAC and may no longer match.
The pattern is the same in both spots, so fold it into a small helper
netcons_release_dev() and route both call sites through it. This makes
the resume-window cleanup consistent with the notifier-driven one so a
later enable does not let netpoll_setup() pick a stale interface by name
when the user bound the target by MAC.
Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Andre Carvalho <asantostc@gmail.com>
Link: https://patch.msgid.link/20260610-netconsole_fix_more-v1-1-a18652c47cef@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
|
|
process_resume_target() removes the target from target_list before
calling resume_target() so that netpoll_setup() can run with interrupts
enabled, then re-adds it once setup completes. netpoll_setup() acquires a
net_device reference (netdev_hold()) and releases the RTNL before
returning.
While the target is off target_list and the RTNL is not held,
netconsole_netdev_event() cannot find it. If the egress device is
unregistered in that window, the NETDEV_UNREGISTER notifier walks
target_list, misses the resuming target, and never tears it down. The
target is then re-added in STATE_ENABLED still holding a reference to the
now-unregistered device, leaking it and hanging unregister_netdevice() in
netdev_wait_allrefs().
Re-check under RTNL before re-publishing the target: if the device left
NETREG_REGISTERED while we were off the list, run do_netpoll_cleanup() and
mark the target disabled. Taking the RTNL across the check and the
list_add() serialises against the NETDEV_UNREGISTER notifier, which also
runs under RTNL, so the device is either still registered (and the
notifier will find the re-added target later) or already unregistering
(and we drop the reference here). netdev_wait_allrefs() runs from
netdev_run_todo() outside the RTNL, so dropping the reference here cannot
deadlock against the pending unregister.
Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20260604-netcons_fix_before_move-v3-5-ab055b3a6aa5@debian.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
|
|
drop_netconsole_target() downgrades a STATE_DEACTIVATED target to
STATE_DISABLED and then only calls netpoll_cleanup() when the target is
STATE_ENABLED. A target becomes STATE_DEACTIVATED when its underlying
interface is unregistered: netconsole_netdev_event() moves it to
target_cleanup_list, and netconsole_process_cleanups_core() is expected
to run do_netpoll_cleanup() on it.
Now that drop_netconsole_target() takes target_cleanup_list_lock around
the unlink, a configfs removal racing with NETDEV_UNREGISTER can pull the
target off target_cleanup_list before the cleanup worker processes it.
The notifier drops the lock before calling
netconsole_process_cleanups_core(), so the worker then iterates a list
that no longer contains the target and never runs do_netpoll_cleanup() on
it. Because drop_netconsole_target() has already rewritten the state to
STATE_DISABLED, its own STATE_ENABLED check is false and netpoll_cleanup()
is skipped too. The net_device reference taken by netpoll_setup() is then
leaked and unregister_netdevice() hangs forever in netdev_wait_allrefs().
Capture whether the target still owns a netpoll before the state is
downgraded and clean it up for both STATE_ENABLED and STATE_DEACTIVATED
targets. netpoll_cleanup() is idempotent -- it skips when np->dev is
already NULL -- so it is safe even when the cleanup worker won the race
and already tore the netpoll down.
Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20260604-netcons_fix_before_move-v3-4-ab055b3a6aa5@debian.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
|
|
drop_netconsole_target() unlinks the target while only holding
target_list_lock. However, when the underlying interface has been
unregistered, netconsole_netdev_event() moves the target from
target_list to target_cleanup_list, and netconsole_process_cleanups_core()
walks that list under target_cleanup_list_lock only.
If a user removes the configfs target at the same time the cleanup
worker is iterating target_cleanup_list, list_del() can corrupt the list
because the two paths take disjoint locks while operating on the same
list node.
Acquire target_cleanup_list_lock around the list_del() so the unlink is
serialised against netconsole_process_cleanups_core() regardless of
which list the target currently belongs to. The state transition that
downgrades STATE_DEACTIVATED to STATE_DISABLED is left intact and is
performed under the same combined locking, preserving the existing
ordering with resume_target().
Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20260604-netcons_fix_before_move-v3-3-ab055b3a6aa5@debian.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
|
|
find_skb() falls back to np->skb_pool when the GFP_ATOMIC alloc_skb()
fails. The pool is refilled by refill_skbs(), which always allocates
buffers of MAX_SKB_SIZE (ethhdr + iphdr + udphdr + MAX_UDP_CHUNK ==
1502 bytes).
netconsole, however, computes the requested length dynamically as
total_len + np->dev->needed_tailroom
If the egress device declares a non-zero needed_tailroom (e.g. some
tunnel or hardware accelerator devices), the required length can exceed
MAX_SKB_SIZE. The pooled skb is then handed back to the caller, which
immediately performs skb_put(skb, len), trips the tail > end check, and
triggers skb_over_panic().
Leave the normal alloc_skb(len, GFP_ATOMIC) path untouched -- the slab
allocator can still satisfy oversized requests when memory is available,
so senders to devices with non-zero needed_tailroom keep working in the
common case. Only the pool fallback is gated: when alloc_skb() failed
and len exceeds the pool buffer size, skip the skb_dequeue() instead of
burning a pre-allocated skb on a request that would later trip
skb_over_panic(). Reserving pool entries for requests they can actually
satisfy also keeps the panic path, which depends on the pool being
primed, intact.
When that drop happens, emit a rate-limited net_warn() so the user
notices that netconsole is unable to push messages on the egress device.
The warn is skipped under in_nmi() for the same reason schedule_work()
is: printk machinery taken by net_warn_ratelimited() is not NMI-safe and
would risk recursing into the same nbcon console we are servicing.
MAX_SKB_SIZE / MAX_UDP_CHUNK were private to net/core/netpoll.c. Move
them to include/linux/netpoll.h so netconsole can reference the same
definition that refill_skbs() uses, keeping the two in sync by
construction. The header now pulls in <linux/ip.h> and <linux/udp.h>
explicitly so MAX_SKB_SIZE remains self-contained for any future user.
Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20260604-netcons_fix_before_move-v3-2-ab055b3a6aa5@debian.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
|
|
When alloc_skb() fails in find_skb(), the fallback path dequeues an skb
from np->skb_pool and unconditionally calls schedule_work() to top the
pool back up. schedule_work() ends up taking the workqueue pool locks,
which are not NMI-safe.
netconsole_write() is registered as the nbcon write_atomic callback and
is explicitly marked CON_NBCON_ATOMIC_UNSAFE, meaning it is invoked from
emergency/panic contexts including NMIs. If the NMI interrupts a thread
already holding the workqueue pool lock, calling schedule_work()
self-deadlocks and the panic message that was being printed is lost.
Introduce netcons_skb_pop() to fold the pool dequeue and the refill
request into a single helper. The helper skips schedule_work() when
called from NMI context; the pool is best-effort, so the refill is simply
deferred to the next non-NMI find_skb() call that exhausts alloc_skb()
and hits the fallback again. This keeps the fast path untouched and the
locking rules around the fallback pool documented in one place.
Note this only removes the schedule_work() hazard from the NMI path. The
allocation itself is still not fully NMI-safe: the alloc_skb(GFP_ATOMIC)
attempted first may take slab locks, and the skb_dequeue() fallback takes
np->skb_pool.lock, so either can deadlock if the NMI interrupts a holder
of those locks. Closing those windows requires an NMI-safe (lockless) skb
pool and is left to a follow-up; this patch addresses the schedule_work()
deadlock, which is both the most likely and the easiest to trigger.
Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20260604-netcons_fix_before_move-v3-1-ab055b3a6aa5@debian.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
|
|
configfs_group_operations
'struct configfs_item_operations' and 'configfs_group_operations' are not
modified in this driver.
Constifying these structures moves some data to a read-only section, so
increases overall security, especially when the structure holds some
function pointers.
On a x86_64, with allmodconfig, as an example:
Before:
======
text data bss dec hex filename
64259 24272 608 89139 15c33 drivers/net/netconsole.o
After:
=====
text data bss dec hex filename
64579 23952 608 89139 15c33 drivers/net/netconsole.o
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/7ff56bdb0cee826a56365f930dcdf457b44931df.1779711734.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
|
|
find_skb() is the netconsole-specific entry into the netpoll skb
pool: every other netpoll consumer (bonding, team, vlan, bridge,
macvlan, dsa) builds its own sk_buff and never touches the pool.
With netpoll_send_udp() (its only caller) now living in netconsole,
find_skb() can join it.
Move find_skb() into drivers/net/netconsole.c as a file-static
helper, drop EXPORT_SYMBOL_GPL(find_skb) and remove its prototype
from include/linux/netpoll.h. find_skb() drains TX completions via
netpoll_zap_completion_queue(), which is already exported in the
NETDEV_INTERNAL namespace, so netconsole picks up
MODULE_IMPORT_NS("NETDEV_INTERNAL") to consume it.
The skb pool's lifecycle (np->skb_pool, np->refill_wq, refill_skbs(),
refill_skbs_work_handler(), skb_pool_flush()) stays in netpoll: it
is initialised in __netpoll_setup() and torn down in
__netpoll_cleanup(), both of which remain netpoll's responsibility.
The refill work queued via schedule_work(&np->refill_wq) from the
moved find_skb() runs refill_skbs_work_handler() in netpoll without
any further plumbing.
This is pure code motion: the function body is unchanged and its
sole caller (netpoll_send_udp(), already moved by an earlier patch)
keeps invoking it the same way. Pre-existing concerns about
find_skb() running from NMI/printk context (zap_completion_queue()
re-entry, skb_pool spinlocks, GFP_ATOMIC allocation, fallback skb
sizing vs. MAX_SKB_SIZE, PREEMPT_RT semantics of __kfree_skb()) are
inherited as-is and are not addressed here; they predate this
series and are out of scope. Fixing them is left for follow-up
work.
Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20260512-netconsole_split-v2-9-1191d14ad66d@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
|
|
netpoll_udp_checksum() computes the UDP checksum for netconsole's
packets. Move it into drivers/net/netconsole.c as a file-static
helper; drop its EXPORT_SYMBOL_GPL and remove the prototype from
include/linux/netpoll.h.
This was the last csum_ipv6_magic() consumer in net/core/netpoll.c,
so drop the now-stale <net/ip6_checksum.h> include there. Pull it
into netconsole.c so the moved code keeps building.
It was also the last udp_hdr() consumer in net/core/netpoll.c. The
file no longer needs anything from <net/udp.h> (the UDP socket-layer
helpers); MAX_SKB_SIZE only needs struct udphdr, which is provided
by the lighter <linux/udp.h>. Swap the include accordingly.
Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20260512-netconsole_split-v2-7-1191d14ad66d@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
|
|
push_udp() builds the UDP header (and triggers the checksum) for
netconsole's UDP packets. Move it into drivers/net/netconsole.c as
a file-static helper; drop its EXPORT_SYMBOL_GPL and remove the
prototype from include/linux/netpoll.h.
Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20260512-netconsole_split-v2-6-1191d14ad66d@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
|
|
push_eth() builds the Ethernet header for netconsole's UDP packets.
Move it into drivers/net/netconsole.c as a file-static helper; drop
its EXPORT_SYMBOL_GPL and remove the prototype from
include/linux/netpoll.h.
Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20260512-netconsole_split-v2-5-1191d14ad66d@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
|
|
push_ipv4() builds the IPv4 header for netconsole's UDP packets.
Move it into drivers/net/netconsole.c as a file-static helper; drop
its EXPORT_SYMBOL_GPL and remove the prototype from
include/linux/netpoll.h.
put_unaligned() is no longer used in net/core/netpoll.c, so drop
the now-stale <linux/unaligned.h> include from there. Pull it into
netconsole.c so the moved code keeps building.
Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20260512-netconsole_split-v2-4-1191d14ad66d@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
|
|
push_ipv6() builds the IPv6 header for netconsole's UDP packets.
Its only caller, netpoll_send_udp(), now lives in netconsole, so
the helper can move there as a file-static function. Drop its
EXPORT_SYMBOL_GPL and remove the prototype from
include/linux/netpoll.h.
Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20260512-netconsole_split-v2-3-1191d14ad66d@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
|
|
Move netpoll_send_udp() from net/core/netpoll.c into
drivers/net/netconsole.c as a static helper, drop EXPORT_SYMBOL(),
and remove the prototype from include/linux/netpoll.h.
netconsole was the only in-tree caller of this entry point. Every
other netpoll consumer (bonding, team, vlan, bridge, macvlan, dsa)
already builds its own sk_buff and hands it to netpoll_send_skb(),
so the netpoll send-side interface is now skb-only.
The helpers it depends on (find_skb(), push_ipv6(), push_ipv4(),
push_udp(), push_eth(), netpoll_udp_checksum()) were exposed in
the previous patches and stay in net/core/netpoll.c for now.
Subsequent patches move each of them into netconsole one at a time
and drop the corresponding EXPORT_SYMBOL_GPL.
Pull <linux/ip.h>, <linux/ipv6.h> and <linux/udp.h> into netconsole.c
so the moved code can name the header structures.
Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20260512-netconsole_split-v2-2-1191d14ad66d@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
|
|
userdatum_value_store() updates udm->value first and only then calls
update_userdata() to rebuild the on-the-wire payload. If
update_userdata() fails (e.g. -ENOMEM from kmalloc), the function
returns the error to userspace, but udm->value already holds the new
string while the live nt->userdata buffer still reflects the old one.
The next successful write to any sibling userdatum on the same target
will call update_userdata() again, which walks every entry and packs
the now-stale udm->value into the payload. The failed write is thus
silently activated later, with no indication to userspace that the
value it tried to set was rejected.
Snapshot the previous value before overwriting udm->value and restore
it if update_userdata() fails so the visible state and the active
payload stay consistent.
Fixes: eb83801af2dc ("netconsole: Dynamic allocation of userdata buffer")
Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20260427-netconsole_ai_fixes-v2-4-59965f29d9cc@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
|
|
dev_name_store() calls strscpy(nt->np.dev_name, buf, IFNAMSIZ) without
checking the return value. If userspace writes an interface name longer
than IFNAMSIZ - 1, strscpy() silently truncates and returns -E2BIG, but
the function ignores it and reports a fully successful write back to
userspace.
If a real interface happens to match the truncated name, netconsole will
bind to the wrong device on the next enable, sending kernel logs and
panic output to an unintended network segment with no indication to
userspace that anything was rewritten.
Reject writes whose length cannot fit in nt->np.dev_name up front:
if (count >= IFNAMSIZ)
return -ENAMETOOLONG;
This is not a big deal of a problem, but, it is still the correct
approach.
Fixes: 0bcc1816188e57 ("[NET] netconsole: Support dynamic reconfiguration using configfs")
Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20260427-netconsole_ai_fixes-v2-3-59965f29d9cc@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
|
|
userdatum_value_store() bounds count by MAX_EXTRADATA_VALUE_LEN (200)
and then copies straight into udm->value, which is itself 200 bytes:
if (count > MAX_EXTRADATA_VALUE_LEN)
return -EMSGSIZE;
...
ret = strscpy(udm->value, buf, sizeof(udm->value));
if (ret < 0)
goto out_unlock;
If userspace writes exactly MAX_EXTRADATA_VALUE_LEN bytes with no NUL
within them, strscpy() copies 199 bytes plus a NUL into udm->value and
returns -E2BIG. The function jumps to out_unlock and reports the error
to userspace, but udm->value has already been overwritten with the
truncated string and update_userdata() is skipped, so the corruption
is not yet visible on the wire.
The next successful write to any userdatum entry under the same target
calls update_userdata(), which packs udm->value into the active
netconsole payload. From that point on, every netconsole message
carries the silently truncated value, and userspace has no indication
that a previous, error-returning write left state behind.
Tighten the entry check from "count > MAX_EXTRADATA_VALUE_LEN" to
"count >= MAX_EXTRADATA_VALUE_LEN". With count strictly less than
sizeof(udm->value), strscpy() can no longer return -E2BIG here, so
the corrupting truncation path is removed entirely.
Fixes: 8a6d5fec6c7f ("net: netconsole: add a userdata config_group member to netconsole_target")
Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20260427-netconsole_ai_fixes-v2-2-59965f29d9cc@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
|
|
Several configfs store callbacks in netconsole end with:
ret = strnlen(buf, count);
This under-reports the number of bytes consumed when the input
contains an embedded NUL within count, telling the VFS that fewer
bytes were written than userspace actually handed in. A conformant
partial-write loop would then retry the trailing bytes against a
callback that has already accepted them.
Every other configfs driver in the tree returns count directly from
its store callbacks once parsing has succeeded, including
drivers/nvme/target/configfs.c, drivers/gpio/gpio-sim.c,
drivers/most/configfs.c, drivers/block/null_blk/main.c,
drivers/pci/endpoint/pci-ep-cfs.c, and the rest of the configfs
users. netconsole was the outlier (along with
drivers/infiniband/core/cma_configfs.c, which has the same latent
issue).
Align netconsole with the rest of the configfs ecosystem: return
count once the parser/validator has accepted the input. The numeric
and boolean parsers (kstrtobool, kstrtou16, mac_pton,
netpoll_parse_ip_addr) have already validated the meaningful prefix;
any trailing bytes are padding and should simply be reported as
consumed.
Fixes: 0bcc1816188e ("[NET] netconsole: Support dynamic reconfiguration using configfs")
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20260427-netconsole_ai_fixes-v2-1-59965f29d9cc@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
|
|
trim_newline() unconditionally dereferences s[len - 1] after computing
len = strnlen(s, maxlen). When the string is empty, len is 0 and the
expression underflows to s[(size_t)-1], reading (and potentially
writing) one byte before the buffer.
The two callers feed trim_newline() with the result of strscpy() from
configfs store callbacks (dev_name_store, userdatum_value_store).
configfs guarantees count >= 1 reaches the callback, but the byte
itself can be NUL: a userspace write(fd, "\0", 1) leaves the
destination empty after strscpy() and triggers the underflow. The OOB
write only fires if the adjacent byte happens to be '\n', so this is
not a security issue, but the access is undefined behaviour either way.
This pattern is commonly flagged by LLM-based code reviewers. While it
is not a security fix, the underlying access is undefined behaviour and
the change is small and self-contained, so it is a reasonable candidate
for the stable trees.
Guard the dereference on a non-zero length.
Fixes: ae001dc67907 ("net: netconsole: move newline trimming to function")
Cc: stable@vger.kernel.org
Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Gustavo Luiz Duarte <gustavold@gmail.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20260420-netcons_trim_newline-v1-1-dc35889aeedf@debian.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
|
|
sysdata_release_enabled_show() checks SYSDATA_TASKNAME instead of
SYSDATA_RELEASE, causing the configfs release_enabled attribute to
reflect the taskname feature state rather than the release feature
state. This is a copy-paste error from the adjacent
sysdata_taskname_enabled_show() function.
The corresponding _store function already uses the correct
SYSDATA_RELEASE flag.
Fixes: 343f90227070 ("netconsole: implement configfs for release_enabled")
Signed-off-by: Breno Leitao <leitao@debian.org>
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260302-sysdata_release_fix-v1-1-e5090f677c7c@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from Paolo Abeni:
"Including fixes from IPsec, Bluetooth and netfilter
Current release - regressions:
- wifi: fix dev_alloc_name() return value check
- rds: fix recursive lock in rds_tcp_conn_slots_available
Current release - new code bugs:
- vsock: lock down child_ns_mode as write-once
Previous releases - regressions:
- core:
- do not pass flow_id to set_rps_cpu()
- consume xmit errors of GSO frames
- netconsole: avoid OOB reads, msg is not nul-terminated
- netfilter: h323: fix OOB read in decode_choice()
- tcp: re-enable acceptance of FIN packets when RWIN is 0
- udplite: fix null-ptr-deref in __udp_enqueue_schedule_skb().
- wifi: brcmfmac: fix potential kernel oops when probe fails
- phy: register phy led_triggers during probe to avoid AB-BA deadlock
- eth:
- bnxt_en: fix deleting of Ntuple filters
- wan: farsync: fix use-after-free bugs caused by unfinished tasklets
- xscale: check for PTP support properly
Previous releases - always broken:
- tcp: fix potential race in tcp_v6_syn_recv_sock()
- kcm: fix zero-frag skb in frag_list on partial sendmsg error
- xfrm:
- fix race condition in espintcp_close()
- always flush state and policy upon NETDEV_UNREGISTER event
- bluetooth:
- purge error queues in socket destructors
- fix response to L2CAP_ECRED_CONN_REQ
- eth:
- mlx5:
- fix circular locking dependency in dump
- fix "scheduling while atomic" in IPsec MAC address query
- gve: fix incorrect buffer cleanup for QPL
- team: avoid NETDEV_CHANGEMTU event when unregistering slave
- usb: validate USB endpoints"
* tag 'net-7.0-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (72 commits)
netfilter: nf_conntrack_h323: fix OOB read in decode_choice()
dpaa2-switch: validate num_ifs to prevent out-of-bounds write
net: consume xmit errors of GSO frames
vsock: document write-once behavior of the child_ns_mode sysctl
vsock: lock down child_ns_mode as write-once
selftests/vsock: change tests to respect write-once child ns mode
net/mlx5e: Fix "scheduling while atomic" in IPsec MAC address query
net/mlx5: Fix missing devlink lock in SRIOV enable error path
net/mlx5: E-switch, Clear legacy flag when moving to switchdev
net/mlx5: LAG, disable MPESW in lag_disable_change()
net/mlx5: DR, Fix circular locking dependency in dump
selftests: team: Add a reference count leak test
team: avoid NETDEV_CHANGEMTU event when unregistering slave
net: mana: Fix double destroy_workqueue on service rescan PCI path
MAINTAINERS: Update maintainer entry for QUALCOMM ETHQOS ETHERNET DRIVER
dpll: zl3073x: Remove redundant cleanup in devm_dpll_init()
selftests/net: packetdrill: Verify acceptance of FIN packets when RWIN is 0
tcp: re-enable acceptance of FIN packets when RWIN is 0
vsock: Use container_of() to get net namespace in sysctl handlers
net: usb: kaweth: validate USB endpoints
...
|
|
msg passed to netconsole from the console subsystem is not guaranteed
to be nul-terminated. Before recent
commit 7eab73b18630 ("netconsole: convert to NBCON console infrastructure")
the message would be placed in printk_shared_pbufs, a static global
buffer, so KASAN had harder time catching OOB accesses. Now we see:
printk: console [netcon_ext0] enabled
BUG: KASAN: slab-out-of-bounds in string+0x1f7/0x240
Read of size 1 at addr ffff88813b6d4c00 by task pr/netcon_ext0/594
CPU: 65 UID: 0 PID: 594 Comm: pr/netcon_ext0 Not tainted 6.19.0-11754-g4246fd6547c9
Call Trace:
kasan_report+0xe4/0x120
string+0x1f7/0x240
vsnprintf+0x655/0xba0
scnprintf+0xba/0x120
netconsole_write+0x3fe/0xa10
nbcon_emit_next_record+0x46e/0x860
nbcon_kthread_func+0x623/0x750
Allocated by task 1:
nbcon_alloc+0x1ea/0x450
register_console+0x26b/0xe10
init_netconsole+0xbb0/0xda0
The buggy address belongs to the object at ffff88813b6d4000
which belongs to the cache kmalloc-4k of size 4096
The buggy address is located 0 bytes to the right of
allocated 3072-byte region [ffff88813b6d4000, ffff88813b6d4c00)
Fixes: c62c0a17f9b7 ("netconsole: Append kernel version to message")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20260219195021.2099699-1-kuba@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
|
|
This was done entirely with mindless brute force, using
git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' |
xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/'
to convert the new alloc_obj() users that had a simple GFP_KERNEL
argument to just drop that argument.
Note that due to the extreme simplicity of the scripting, any slightly
more complex cases spread over multiple lines would not be triggered:
they definitely exist, but this covers the vast bulk of the cases, and
the resulting diff is also then easier to check automatically.
For the same reason the 'flex' versions will be done as a separate
conversion.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:
Single allocations: kmalloc(sizeof(TYPE), ...)
are replaced with: kmalloc_obj(TYPE, ...)
Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with: kmalloc_objs(TYPE, COUNT, ...)
Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...)
(where TYPE may also be *VAR)
The resulting allocations no longer return "void *", instead returning
"TYPE *".
Signed-off-by: Kees Cook <kees@kernel.org>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull non-MM updates from Andrew Morton:
- "ocfs2: give ocfs2 the ability to reclaim suballocator free bg" saves
disk space by teaching ocfs2 to reclaim suballocator block group
space (Heming Zhao)
- "Add ARRAY_END(), and use it to fix off-by-one bugs" adds the
ARRAY_END() macro and uses it in various places (Alejandro Colomar)
- "vmcoreinfo: support VMCOREINFO_BYTES larger than PAGE_SIZE" makes
the vmcore code future-safe, if VMCOREINFO_BYTES ever exceeds the
page size (Pnina Feder)
- "kallsyms: Prevent invalid access when showing module buildid" cleans
up kallsyms code related to module buildid and fixes an invalid
access crash when printing backtraces (Petr Mladek)
- "Address page fault in ima_restore_measurement_list()" fixes a
kexec-related crash that can occur when booting the second-stage
kernel on x86 (Harshit Mogalapalli)
- "kho: ABI headers and Documentation updates" updates the kexec
handover ABI documentation (Mike Rapoport)
- "Align atomic storage" adds the __aligned attribute to atomic_t and
atomic64_t definitions to get natural alignment of both types on
csky, m68k, microblaze, nios2, openrisc and sh (Finn Thain)
- "kho: clean up page initialization logic" simplifies the page
initialization logic in kho_restore_page() (Pratyush Yadav)
- "Unload linux/kernel.h" moves several things out of kernel.h and into
more appropriate places (Yury Norov)
- "don't abuse task_struct.group_leader" removes the usage of
->group_leader when it is "obviously unnecessary" (Oleg Nesterov)
- "list private v2 & luo flb" adds some infrastructure improvements to
the live update orchestrator (Pasha Tatashin)
* tag 'mm-nonmm-stable-2026-02-12-10-48' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (107 commits)
watchdog/hardlockup: simplify perf event probe and remove per-cpu dependency
procfs: fix missing RCU protection when reading real_parent in do_task_stat()
watchdog/softlockup: fix sample ring index wrap in need_counting_irqs()
kcsan, compiler_types: avoid duplicate type issues in BPF Type Format
kho: fix doc for kho_restore_pages()
tests/liveupdate: add in-kernel liveupdate test
liveupdate: luo_flb: introduce File-Lifecycle-Bound global state
liveupdate: luo_file: Use private list
list: add kunit test for private list primitives
list: add primitives for private list manipulations
delayacct: fix uapi timespec64 definition
panic: add panic_force_cpu= parameter to redirect panic to a specific CPU
netclassid: use thread_group_leader(p) in update_classid_task()
RDMA/umem: don't abuse current->group_leader
drm/pan*: don't abuse current->group_leader
drm/amd: kill the outdated "Only the pthreads threading model is supported" checks
drm/amdgpu: don't abuse current->group_leader
android/binder: use same_thread_group(proc->tsk, current) in binder_mmap()
android/binder: don't abuse current->group_leader
kho: skip memoryless NUMA nodes when reserving scratch areas
...
|
|
Use the CPU and task name captured at printk() time from
nbcon_write_context instead of querying the current execution context.
This provides accurate information about where the message originated,
rather than where netconsole happens to be running.
For CPU, use wctxt->cpu instead of raw_smp_processor_id().
For taskname, use wctxt->comm directly which contains the task
name captured at printk time.
This change ensures netconsole outputs reflect the actual context that
generated the log message, which is especially important when the
console driver runs asynchronously in a dedicated thread.
Reviewed-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20260206-nbcon-v7-4-62bda69b1b41@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
|
|
Convert netconsole from the legacy console API to the NBCON framework.
NBCON provides threaded printing which unblocks printk()s and flushes in
a thread, decoupling network TX from printk() when netconsole is
in use.
Since netconsole relies on the network stack which cannot safely operate
from all atomic contexts, mark both consoles with
CON_NBCON_ATOMIC_UNSAFE. (See discussion in [1])
CON_NBCON_ATOMIC_UNSAFE restricts write_atomic() usage to emergency
scenarios (panic) where regular messages are sent in threaded mode.
Implementation changes:
- Unify write_ext_msg() and write_msg() into netconsole_write()
- Add device_lock/device_unlock callbacks to manage target_list_lock
- Use nbcon_enter_unsafe()/nbcon_exit_unsafe() around network
operations.
- If nbcon_enter_unsafe() fails, just return given netconsole lost
the ownership of the console.
- Set write_thread and write_atomic callbacks (both use same function)
Link: https://lore.kernel.org/all/b2qps3uywhmjaym4mht2wpxul4yqtuuayeoq4iv4k3zf5wdgh3@tocu6c7mj4lt/ [1]
Reviewed-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20260206-nbcon-v7-3-62bda69b1b41@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
|
|
Extract the message fragmentation logic from write_msg() into a
dedicated send_msg_udp() function. This improves code readability
and prepares for future enhancements.
The new send_msg_udp() function handles splitting messages that
exceed MAX_PRINT_CHUNK into smaller fragments and sending them
sequentially. This function is placed before send_ext_msg_udp()
to maintain a logical ordering of related functions.
No functional changes - this is purely a refactoring commit.
Reviewed-by: Petr Mladek <pmladek@suse.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Reviewed-by: John Ogness <john.ogness@linutronix.de>
Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20260206-nbcon-v7-2-62bda69b1b41@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
|
|
Attempt to resume a previously deactivated target when the associated
interface comes back (NETDEV_REGISTER) or when it changes name
(NETDEV_CHANGENAME) by calling netpoll_setup on the device.
Depending on how the target was setup (by mac or interface name), the
corresponding field is compared with the device being brought up. Targets
that match the incoming device, are scheduled for resume on a workqueue.
Resuming happens on a workqueue as we can't execute netpoll_setup in the
context of the netdev event. A standalone workqueue (as opposed to the
global one) is used to allow for proper cleanup process during
netconsole module cleanup as we need to be able to flush all pending
work before traversing the target list given that targets are temporarily
removed from the list during resume_target.
Target transitions to STATE_DISABLED in case of failures resuming it to
avoid retrying the same target indefinitely.
Signed-off-by: Andre Carvalho <asantostc@gmail.com>
Reviewed-by: Breno Leitao <leitao@debian.org>
Tested-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20260118-netcons-retrigger-v11-6-4de36aebcf48@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
|
|
This commit introduces two helper functions to perform lock/unlock on
dynamic_netconsole_mutex providing no-op stub versions when compiled
without CONFIG_NETCONSOLE_DYNAMIC and refactors existing call sites to
use the new helpers.
This is done following kernel coding style guidelines, in preparation
for an upcoming change. It avoids the need for preprocessor conditionals
in the call site and keeps the logic easier to follow.
Signed-off-by: Andre Carvalho <asantostc@gmail.com>
Reviewed-by: Breno Leitao <leitao@debian.org>
Tested-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20260118-netcons-retrigger-v11-5-4de36aebcf48@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
|
