linux-stable.git/net/sched/sch_codel.c, branch linux-rolling-stable Linux kernel stable tree net/sched: sch_codel: Do not call qdisc_tree_reduce_backlog during peek before restoring qlen 2026-07-24T14:19:51+00:00 Victor Nogueira victor@mojatatu.com 2026-06-10T19:28:53+00:00 91e0a793a72374c20ab31a40ccec21373e82e973 [ Upstream commit 52f1da34c9f4d5bdc1e8b44242da5c7ba8db85f3 ] Whenever codel drops packets during peek, it calls qdisc_tree_reduce_backlog. An issue arises because it calls qdisc_tree_reduce_backlog before it reincrements the qlen. If qlen drops to zero, but peek returns an skb, the parent's qlen_notify callback will be executed even though codel still has 1 packet on the queue and, thus, will mistakenly deactivate the parent's class causing issues like a wild memory access when qfq has codel as a child: [ 36.339843][ T370] Oops: general protection fault, probably for non-canonical address 0xfbd59c0000000024: 0000 [#1] SMP KASAN NOPTI [ 36.340408][ T370] KASAN: maybe wild-memory-access in range [0xdead000000000120-0xdead000000000127] [ 36.340737][ T370] CPU: 2 UID: 0 PID: 370 Comm: tc Not tainted 7.1.0-rc5-00287-g66e13b626592 #87 PREEMPT(full) [ 36.341113][ T370] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 [ 36.341357][ T370] RIP: 0010:qfq_deactivate_agg (include/linux/list.h:1029 (discriminator 2) include/linux/list.h:1043 (discriminator 2) net/sched/sch_qfq.c:1369 (discriminator 2) net/sched/sch_qfq.c:1395 (discriminator 2)) sch_qfq [ 36.342221][ T370] RSP: 0018:ffff8881100ef370 EFLAGS: 00010216 [ 36.342422][ T370] RAX: 0000000000000000 RBX: ffff8881058a9568 RCX: dffffc0000000000 [ 36.342664][ T370] RDX: 1ffff11021064dc3 RSI: ffff888108326e00 RDI: dffffc0000000000 [ 36.342905][ T370] RBP: ffff8881058a8280 R08: dead000000000122 R09: 1bd5a00000000024 [ 36.343140][ T370] R10: fffffbfff2940329 R11: fffffbfff2940329 R12: 0000000000000000 [ 36.343383][ T370] R13: dead000000000100 R14: ffff8881058a9580 R15: ffff8881058a9578 [ 36.343631][ T370] FS: 00007fc04b0ca780(0000) GS:ffff888184fef000(0000) knlGS:0000000000000000 [ 36.343911][ T370] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 36.344116][ T370] CR2: 0000557c02c02000 CR3: 000000010e0ba000 CR4: 0000000000750ef0 [ 36.344359][ T370] PKRU: 55555554 [ 36.344481][ T370] Call Trace: ... [ 36.345054][ T370] qfq_reset_qdisc (net/sched/sch_qfq.c:357 net/sched/sch_qfq.c:1487) sch_qfq [ 36.345222][ T370] qdisc_reset (net/sched/sch_generic.c:1057) [ 36.345503][ T370] __qdisc_destroy (net/sched/sch_generic.c:1096) [ 36.345677][ T370] qdisc_graft (net/sched/sch_api.c:1062 net/sched/sch_api.c:1053 net/sched/sch_api.c:1159) [ 36.346335][ T370] tc_get_qdisc (net/sched/sch_api.c:1528 net/sched/sch_api.c:1556) Fix this by only calling qdisc_tree_reduce_backlog in peek after the qlen is restored. Fixes: 342debc12183 ("codel: remove sch->q.qlen check before qdisc_tree_reduce_backlog()") Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Victor Nogueira <victor@mojatatu.com> Link: https://patch.msgid.link/20260610192855.3121513-3-victor@mojatatu.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 52f1da34c9f4d5bdc1e8b44242da5c7ba8db85f3 ]

Whenever codel drops packets during peek, it calls
qdisc_tree_reduce_backlog. An issue arises because it calls
qdisc_tree_reduce_backlog before it reincrements the qlen. If qlen drops
to zero, but peek returns an skb, the parent's qlen_notify callback will
be executed even though codel still has 1 packet on the queue and, thus,
will mistakenly deactivate the parent's class causing issues like a wild
memory access when qfq has codel as a child:

[   36.339843][  T370] Oops: general protection fault, probably for non-canonical address 0xfbd59c0000000024: 0000 [#1] SMP KASAN NOPTI
[   36.340408][  T370] KASAN: maybe wild-memory-access in range [0xdead000000000120-0xdead000000000127]
[   36.340737][  T370] CPU: 2 UID: 0 PID: 370 Comm: tc Not tainted 7.1.0-rc5-00287-g66e13b626592 #87 PREEMPT(full)
[   36.341113][  T370] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   36.341357][  T370] RIP: 0010:qfq_deactivate_agg (include/linux/list.h:1029 (discriminator 2) include/linux/list.h:1043 (discriminator 2) net/sched/sch_qfq.c:1369 (discriminator 2) net/sched/sch_qfq.c:1395 (discriminator 2)) sch_qfq
[   36.342221][  T370] RSP: 0018:ffff8881100ef370 EFLAGS: 00010216
[   36.342422][  T370] RAX: 0000000000000000 RBX: ffff8881058a9568 RCX: dffffc0000000000
[   36.342664][  T370] RDX: 1ffff11021064dc3 RSI: ffff888108326e00 RDI: dffffc0000000000
[   36.342905][  T370] RBP: ffff8881058a8280 R08: dead000000000122 R09: 1bd5a00000000024
[   36.343140][  T370] R10: fffffbfff2940329 R11: fffffbfff2940329 R12: 0000000000000000
[   36.343383][  T370] R13: dead000000000100 R14: ffff8881058a9580 R15: ffff8881058a9578
[   36.343631][  T370] FS:  00007fc04b0ca780(0000) GS:ffff888184fef000(0000) knlGS:0000000000000000
[   36.343911][  T370] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   36.344116][  T370] CR2: 0000557c02c02000 CR3: 000000010e0ba000 CR4: 0000000000750ef0
[   36.344359][  T370] PKRU: 55555554
[   36.344481][  T370] Call Trace:
...
[   36.345054][  T370] qfq_reset_qdisc (net/sched/sch_qfq.c:357 net/sched/sch_qfq.c:1487) sch_qfq
[   36.345222][  T370]  qdisc_reset (net/sched/sch_generic.c:1057)
[   36.345503][  T370]  __qdisc_destroy (net/sched/sch_generic.c:1096)
[   36.345677][  T370]  qdisc_graft (net/sched/sch_api.c:1062 net/sched/sch_api.c:1053 net/sched/sch_api.c:1159)
[   36.346335][  T370]  tc_get_qdisc (net/sched/sch_api.c:1528 net/sched/sch_api.c:1556)

Fix this by only calling qdisc_tree_reduce_backlog in peek after the
qlen is restored.

Fixes: 342debc12183 ("codel: remove sch->q.qlen check before qdisc_tree_reduce_backlog()")
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Victor Nogueira <victor@mojatatu.com>
Link: https://patch.msgid.link/20260610192855.3121513-3-victor@mojatatu.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
codel: annotate data-races in codel_dump_stats() 2026-04-09T02:18:52+00:00 Eric Dumazet edumazet@google.com 2026-04-07T14:30:53+00:00 ea25e03da7a79e0413f1606d4a407a97ed41628a codel_dump_stats() only runs with RTNL held, reading fields that can be changed in qdisc fast path. Add READ_ONCE()/WRITE_ONCE() annotations. Alternative would be to acquire the qdisc spinlock, but our long-term goal is to make qdisc dump operations lockless as much as we can. tc_codel_xstats fields don't need to be latched atomically, otherwise this bug would have been caught earlier. No change in kernel size: $ scripts/bloat-o-meter -t vmlinux.0 vmlinux add/remove: 0/0 grow/shrink: 1/1 up/down: 3/-1 (2) Function old new delta codel_qdisc_dequeue 2462 2465 +3 codel_dump_stats 250 249 -1 Total: Before=29739919, After=29739921, chg +0.00% Fixes: 76e3cc126bb2 ("codel: Controlled Delay AQM") Signed-off-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20260407143053.1570620-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
codel_dump_stats() only runs with RTNL held,
reading fields that can be changed in qdisc fast path.

Add READ_ONCE()/WRITE_ONCE() annotations.

Alternative would be to acquire the qdisc spinlock, but our long-term
goal is to make qdisc dump operations lockless as much as we can.

tc_codel_xstats fields don't need to be latched atomically,
otherwise this bug would have been caught earlier.

No change in kernel size:

$ scripts/bloat-o-meter -t vmlinux.0 vmlinux
add/remove: 0/0 grow/shrink: 1/1 up/down: 3/-1 (2)
Function                                     old     new   delta
codel_qdisc_dequeue                         2462    2465      +3
codel_dump_stats                             250     249      -1
Total: Before=29739919, After=29739921, chg +0.00%

Fixes: 76e3cc126bb2 ("codel: Controlled Delay AQM")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260407143053.1570620-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
net: sched: introduce qdisc-specific drop reason tracing 2026-02-28T23:31:34+00:00 Jesper Dangaard Brouer hawk@kernel.org 2026-02-26T13:44:12+00:00 ff2998f29f390d963299103f0b247cc79106ced5 Create new enum qdisc_drop_reason and trace_qdisc_drop tracepoint for qdisc layer drop diagnostics with direct qdisc context visibility. The new tracepoint includes qdisc handle, parent, kind (name), and device information. Existing SKB_DROP_REASON_QDISC_DROP is retained for backwards compatibility via kfree_skb_reason(). Convert qdiscs with drop reasons to use the new infrastructure. Change CAKE's cobalt_should_drop() return type from enum skb_drop_reason to enum qdisc_drop_reason to fix implicit enum conversion warnings. Use QDISC_DROP_UNSPEC as the 'not dropped' sentinel instead of SKB_NOT_DROPPED_YET. Both have the same compiled value (0), so the comparison logic remains semantically equivalent. Signed-off-by: Jesper Dangaard Brouer <hawk@kernel.org> Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com> Link: https://patch.msgid.link/177211345275.3011628.1974310302645218067.stgit@firesoul Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Create new enum qdisc_drop_reason and trace_qdisc_drop tracepoint
for qdisc layer drop diagnostics with direct qdisc context visibility.

The new tracepoint includes qdisc handle, parent, kind (name), and
device information. Existing SKB_DROP_REASON_QDISC_DROP is retained
for backwards compatibility via kfree_skb_reason().

Convert qdiscs with drop reasons to use the new infrastructure.

Change CAKE's cobalt_should_drop() return type from enum skb_drop_reason
to enum qdisc_drop_reason to fix implicit enum conversion warnings.
Use QDISC_DROP_UNSPEC as the 'not dropped' sentinel instead of
SKB_NOT_DROPPED_YET. Both have the same compiled value (0), so the
comparison logic remains semantically equivalent.

Signed-off-by: Jesper Dangaard Brouer <hawk@kernel.org>
Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://patch.msgid.link/177211345275.3011628.1974310302645218067.stgit@firesoul
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
net_sched: use qdisc_dequeue_drop() in cake, codel, fq_codel 2025-11-25T15:10:32+00:00 Eric Dumazet edumazet@google.com 2025-11-21T08:32:56+00:00 a6efc273ab8245722eee2150fa12cf75781dc410 cake, codel and fq_codel can drop many packets from dequeue(). Use qdisc_dequeue_drop() so that the freeing can happen outside of the qdisc spinlock scope. Add TCQ_F_DEQUEUE_DROPS to sch->flags. Signed-off-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20251121083256.674562-15-edumazet@google.com Signed-off-by: Paolo Abeni <pabeni@redhat.com> 
cake, codel and fq_codel can drop many packets from dequeue().

Use qdisc_dequeue_drop() so that the freeing can happen
outside of the qdisc spinlock scope.

Add TCQ_F_DEQUEUE_DROPS to sch->flags.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20251121083256.674562-15-edumazet@google.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
net/sched: Fix backlog accounting in qdisc_dequeue_internal 2025-08-15T00:52:29+00:00 William Liu will@willsroot.io 2025-08-12T23:57:57+00:00 52bf272636bda69587952b35ae97690b8dc89941 This issue applies for the following qdiscs: hhf, fq, fq_codel, and fq_pie, and occurs in their change handlers when adjusting to the new limit. The problem is the following in the values passed to the subsequent qdisc_tree_reduce_backlog call given a tbf parent: When the tbf parent runs out of tokens, skbs of these qdiscs will be placed in gso_skb. Their peek handlers are qdisc_peek_dequeued, which accounts for both qlen and backlog. However, in the case of qdisc_dequeue_internal, ONLY qlen is accounted for when pulling from gso_skb. This means that these qdiscs are missing a qdisc_qstats_backlog_dec when dropping packets to satisfy the new limit in their change handlers. One can observe this issue with the following (with tc patched to support a limit of 0): export TARGET=fq tc qdisc del dev lo root tc qdisc add dev lo root handle 1: tbf rate 8bit burst 100b latency 1ms tc qdisc replace dev lo handle 3: parent 1:1 $TARGET limit 1000 echo ''; echo 'add child'; tc -s -d qdisc show dev lo ping -I lo -f -c2 -s32 -W0.001 127.0.0.1 2>&1 >/dev/null echo ''; echo 'after ping'; tc -s -d qdisc show dev lo tc qdisc change dev lo handle 3: parent 1:1 $TARGET limit 0 echo ''; echo 'after limit drop'; tc -s -d qdisc show dev lo tc qdisc replace dev lo handle 2: parent 1:1 sfq echo ''; echo 'post graft'; tc -s -d qdisc show dev lo The second to last show command shows 0 packets but a positive number (74) of backlog bytes. The problem becomes clearer in the last show command, where qdisc_purge_queue triggers qdisc_tree_reduce_backlog with the positive backlog and causes an underflow in the tbf parent's backlog (4096 Mb instead of 0). To fix this issue, the codepath for all clients of qdisc_dequeue_internal has been simplified: codel, pie, hhf, fq, fq_pie, and fq_codel. qdisc_dequeue_internal handles the backlog adjustments for all cases that do not directly use the dequeue handler. The old fq_codel_change limit adjustment loop accumulated the arguments to the subsequent qdisc_tree_reduce_backlog call through the cstats field. However, this is confusing and error prone as fq_codel_dequeue could also potentially mutate this field (which qdisc_dequeue_internal calls in the non gso_skb case), so we have unified the code here with other qdiscs. Fixes: 2d3cbfd6d54a ("net_sched: Flush gso_skb list too during ->change()") Fixes: 4b549a2ef4be ("fq_codel: Fair Queue Codel AQM") Fixes: 10239edf86f1 ("net-qdisc-hhf: Heavy-Hitter Filter (HHF) qdisc") Signed-off-by: William Liu <will@willsroot.io> Reviewed-by: Savino Dicanosa <savy@syst3mfailure.io> Link: https://patch.msgid.link/20250812235725.45243-1-will@willsroot.io Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
This issue applies for the following qdiscs: hhf, fq, fq_codel, and
fq_pie, and occurs in their change handlers when adjusting to the new
limit. The problem is the following in the values passed to the
subsequent qdisc_tree_reduce_backlog call given a tbf parent:

   When the tbf parent runs out of tokens, skbs of these qdiscs will
   be placed in gso_skb. Their peek handlers are qdisc_peek_dequeued,
   which accounts for both qlen and backlog. However, in the case of
   qdisc_dequeue_internal, ONLY qlen is accounted for when pulling
   from gso_skb. This means that these qdiscs are missing a
   qdisc_qstats_backlog_dec when dropping packets to satisfy the
   new limit in their change handlers.

   One can observe this issue with the following (with tc patched to
   support a limit of 0):

   export TARGET=fq
   tc qdisc del dev lo root
   tc qdisc add dev lo root handle 1: tbf rate 8bit burst 100b latency 1ms
   tc qdisc replace dev lo handle 3: parent 1:1 $TARGET limit 1000
   echo ''; echo 'add child'; tc -s -d qdisc show dev lo
   ping -I lo -f -c2 -s32 -W0.001 127.0.0.1 2>&1 >/dev/null
   echo ''; echo 'after ping'; tc -s -d qdisc show dev lo
   tc qdisc change dev lo handle 3: parent 1:1 $TARGET limit 0
   echo ''; echo 'after limit drop'; tc -s -d qdisc show dev lo
   tc qdisc replace dev lo handle 2: parent 1:1 sfq
   echo ''; echo 'post graft'; tc -s -d qdisc show dev lo

   The second to last show command shows 0 packets but a positive
   number (74) of backlog bytes. The problem becomes clearer in the
   last show command, where qdisc_purge_queue triggers
   qdisc_tree_reduce_backlog with the positive backlog and causes an
   underflow in the tbf parent's backlog (4096 Mb instead of 0).

To fix this issue, the codepath for all clients of qdisc_dequeue_internal
has been simplified: codel, pie, hhf, fq, fq_pie, and fq_codel.
qdisc_dequeue_internal handles the backlog adjustments for all cases that
do not directly use the dequeue handler.

The old fq_codel_change limit adjustment loop accumulated the arguments to
the subsequent qdisc_tree_reduce_backlog call through the cstats field.
However, this is confusing and error prone as fq_codel_dequeue could also
potentially mutate this field (which qdisc_dequeue_internal calls in the
non gso_skb case), so we have unified the code here with other qdiscs.

Fixes: 2d3cbfd6d54a ("net_sched: Flush gso_skb list too during ->change()")
Fixes: 4b549a2ef4be ("fq_codel: Fair Queue Codel AQM")
Fixes: 10239edf86f1 ("net-qdisc-hhf: Heavy-Hitter Filter (HHF) qdisc")
Signed-off-by: William Liu <will@willsroot.io>
Reviewed-by: Savino Dicanosa <savy@syst3mfailure.io>
Link: https://patch.msgid.link/20250812235725.45243-1-will@willsroot.io
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
net_sched: Flush gso_skb list too during ->change() 2025-05-09T11:34:38+00:00 Cong Wang xiyou.wangcong@gmail.com 2025-05-07T04:35:58+00:00 2d3cbfd6d54a2c39ce3244f33f85c595844bd7b8 Previously, when reducing a qdisc's limit via the ->change() operation, only the main skb queue was trimmed, potentially leaving packets in the gso_skb list. This could result in NULL pointer dereference when we only check sch->limit against sch->q.qlen. This patch introduces a new helper, qdisc_dequeue_internal(), which ensures both the gso_skb list and the main queue are properly flushed when trimming excess packets. All relevant qdiscs (codel, fq, fq_codel, fq_pie, hhf, pie) are updated to use this helper in their ->change() routines. Fixes: 76e3cc126bb2 ("codel: Controlled Delay AQM") Fixes: 4b549a2ef4be ("fq_codel: Fair Queue Codel AQM") Fixes: afe4fd062416 ("pkt_sched: fq: Fair Queue packet scheduler") Fixes: ec97ecf1ebe4 ("net: sched: add Flow Queue PIE packet scheduler") Fixes: 10239edf86f1 ("net-qdisc-hhf: Heavy-Hitter Filter (HHF) qdisc") Fixes: d4b36210c2e6 ("net: pkt_sched: PIE AQM scheme") Reported-by: Will <willsroot@protonmail.com> Reported-by: Savy <savy@syst3mfailure.io> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
Previously, when reducing a qdisc's limit via the ->change() operation, only
the main skb queue was trimmed, potentially leaving packets in the gso_skb
list. This could result in NULL pointer dereference when we only check
sch->limit against sch->q.qlen.

This patch introduces a new helper, qdisc_dequeue_internal(), which ensures
both the gso_skb list and the main queue are properly flushed when trimming
excess packets. All relevant qdiscs (codel, fq, fq_codel, fq_pie, hhf, pie)
are updated to use this helper in their ->change() routines.

Fixes: 76e3cc126bb2 ("codel: Controlled Delay AQM")
Fixes: 4b549a2ef4be ("fq_codel: Fair Queue Codel AQM")
Fixes: afe4fd062416 ("pkt_sched: fq: Fair Queue packet scheduler")
Fixes: ec97ecf1ebe4 ("net: sched: add Flow Queue PIE packet scheduler")
Fixes: 10239edf86f1 ("net-qdisc-hhf: Heavy-Hitter Filter (HHF) qdisc")
Fixes: d4b36210c2e6 ("net: pkt_sched: PIE AQM scheme")
Reported-by: Will <willsroot@protonmail.com>
Reported-by: Savy <savy@syst3mfailure.io>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
codel: remove sch->q.qlen check before qdisc_tree_reduce_backlog() 2025-04-08T08:57:56+00:00 Cong Wang xiyou.wangcong@gmail.com 2025-04-03T21:16:31+00:00 342debc12183b51773b3345ba267e9263bdfaaef After making all ->qlen_notify() callbacks idempotent, now it is safe to remove the check of qlen!=0 from both fq_codel_dequeue() and codel_qdisc_dequeue(). Reported-by: Gerrard Tai <gerrard.tai@starlabs.sg> Fixes: 4b549a2ef4be ("fq_codel: Fair Queue Codel AQM") Fixes: 76e3cc126bb2 ("codel: Controlled Delay AQM") Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://patch.msgid.link/20250403211636.166257-1-xiyou.wangcong@gmail.com Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com> 
After making all ->qlen_notify() callbacks idempotent, now it is safe to
remove the check of qlen!=0 from both fq_codel_dequeue() and
codel_qdisc_dequeue().

Reported-by: Gerrard Tai <gerrard.tai@starlabs.sg>
Fixes: 4b549a2ef4be ("fq_codel: Fair Queue Codel AQM")
Fixes: 76e3cc126bb2 ("codel: Controlled Delay AQM")
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250403211636.166257-1-xiyou.wangcong@gmail.com
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
net/sched: Add drop reasons for AQM-based qdiscs 2024-12-17T12:27:29+00:00 Toke Høiland-Jørgensen toke@redhat.com 2024-12-14T16:50:59+00:00 ff9f17ce2e53887e74fc0e72711ece42526836ed Now that we have generic QDISC_CONGESTED and QDISC_OVERLIMIT drop reasons, let's have all the qdiscs that contain an AQM apply them consistently when dropping packets. Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com> Link: https://patch.msgid.link/20241214-fq-codel-drop-reasons-v1-1-2a814e884c37@redhat.com Signed-off-by: Paolo Abeni <pabeni@redhat.com> 
Now that we have generic QDISC_CONGESTED and QDISC_OVERLIMIT drop
reasons, let's have all the qdiscs that contain an AQM apply them
consistently when dropping packets.

Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://patch.msgid.link/20241214-fq-codel-drop-reasons-v1-1-2a814e884c37@redhat.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
net_sched: sch_codel: implement lockless codel_dump() 2024-04-19T10:34:07+00:00 Eric Dumazet edumazet@google.com 2024-04-18T07:32:39+00:00 c45bd26c829ea229c067f4096a746ea2f717bc20 Instead of relying on RTNL, codel_dump() can use READ_ONCE() annotations, paired with WRITE_ONCE() ones in codel_change(). Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Simon Horman <horms@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net> 
Instead of relying on RTNL, codel_dump() can use READ_ONCE()
annotations, paired with WRITE_ONCE() ones in codel_change().

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
net: sched: codel replace GPLv2/BSD boilerplate 2024-02-13T12:45:19+00:00 Stephen Hemminger stephen@networkplumber.org 2024-02-11T17:24:55+00:00 32c7eec21c11e149a9195cf0d48cc530d1e5a637 The prologue to codel is using BSD-3 clause and GPL-2 boiler plate language. Replace it by using SPDX. The automated treewide scan in commit d2912cb15bdd ("treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500") did not pickup dual licensed code. Signed-off-by: Stephen Hemminger <stephen@networkplumber.org> Acked-by: Dave Taht <dave.taht@gmail.com> Link: https://lore.kernel.org/r/20240211172532.6568-1-stephen@networkplumber.org Signed-off-by: Paolo Abeni <pabeni@redhat.com> 
The prologue to codel is using BSD-3 clause and GPL-2 boiler plate
language. Replace it by using SPDX. The automated treewide scan in
commit d2912cb15bdd ("treewide: Replace GPLv2 boilerplate/reference with
SPDX - rule 500") did not pickup dual licensed code.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Acked-by: Dave Taht <dave.taht@gmail.com>
Link: https://lore.kernel.org/r/20240211172532.6568-1-stephen@networkplumber.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>