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Fix AF_XDP backport - #8

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PeterKnecht93 wants to merge 6 commits into
PhoenixKernel:android-4.14-phoenixfrom
PeterKnecht93:xdp-fix
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Fix AF_XDP backport#8
PeterKnecht93 wants to merge 6 commits into
PhoenixKernel:android-4.14-phoenixfrom
PeterKnecht93:xdp-fix

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Commit fcdc94b (UPSTREAM: xsk: support for Tx) of the 5.10 BPF backport introduced a call to dev_direct_xmit, but the actual function and its dependencies were never backported, resulting in the following compilation error when enabling CONFIG_XDP_SOCKETS:

net/xdp/xsk.c:279:9: error: implicit declaration of function 'dev_direct_xmit' [-Werror,-Wimplicit-function-declaration]
err = dev_direct_xmit(skb, xs->queue_id);
^
net/xdp/xsk.c:279:9: note: did you mean 'dev_queue_xmit'?
./include/linux/netdevice.h:2573:5: note: 'dev_queue_xmit' declared here
int dev_queue_xmit(struct sk_buff *skb);
^
1 error generated.

This PR merges the remaining commits to fix AF_XDP.

klassert and others added 6 commits March 25, 2026 13:49
We change the ESP GSO handlers to only segment the packets.
The ESP handling and encryption is defered to validate_xmit_xfrm()
where this is done for non GRO packets too. This makes the code
more robust and prepares for asynchronous crypto handling.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Louis Poier <lpoier7@proton.me>
This patch implements asynchronous crypto callbacks
and a backlog handler that can be used when IPsec
is done at layer 2 in the TX path. It also extends
the skb validate functions so that we can update
the driver transmit return codes based on async
crypto operation or to indicate that we queued the
packet in a backlog queue.

Joint work with: Aviv Heller <avivh@mellanox.com>

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Louis Poier <lpoier7@proton.me>
The new dev_direct_xmit will be used by AF_XDP in later commits.

Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
…re crypto.

We now have support for asynchronous crypto operations in the layer 2 TX
path. This was the missing part to allow the GSO codepath for software
crypto, so allow this codepath now.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
The offload_handle should be an opaque data cookie for the driver
to use, much like the data cookie for a timer or alarm callback.
Thus, the XFRM stack should not be checking for non-zero, because
the driver might use that to store an array reference, which could
be zero, or some other zero but meaningful value.

We can remove the checks for non-zero because there are plenty
other attributes also being checked to see if there is an offload
in place for the SA in question.

Signed-off-by: Shannon Nelson <shannon.nelson@oracle.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
These references to the umem will be used to store information
on what kind of AF_XDP umem that is bound to a queue id, if any.

Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Louis Poier <lpoier7@proton.me>
vrdons added a commit to mt6768-S/android_kernel_xiaomi_mt6768 that referenced this pull request Jul 4, 2026
vrdons added a commit to mt6768-S/android_kernel_xiaomi_mt6768 that referenced this pull request Jul 4, 2026
vrdons added a commit to mt6768-S/android_kernel_xiaomi_mt6768 that referenced this pull request Jul 4, 2026
ExtremeXT pushed a commit that referenced this pull request Jul 23, 2026
commit 77e45145e3039a0fb212556ab3f8c87f54771757 upstream.

napi_schedule() is expected to be called either:

* From an interrupt, where raised softirqs are handled on IRQ exit

* From a softirq disabled section, where raised softirqs are handled on
  the next call to local_bh_enable().

* From a softirq handler, where raised softirqs are handled on the next
  round in do_softirq(), or further deferred to a dedicated kthread.

Other bare tasks context may end up ignoring the raised NET_RX vector
until the next random softirq handling opportunity, which may not
happen before a while if the CPU goes idle afterwards with the tick
stopped.

Such "misuses" have been detected on several places thanks to messages
of the kind:

	"NOHZ tick-stop error: local softirq work is pending, handler #8!!!"

For example:

       __raise_softirq_irqoff
        __napi_schedule
        rtl8152_runtime_resume.isra.0
        rtl8152_resume
        usb_resume_interface.isra.0
        usb_resume_both
        __rpm_callback
        rpm_callback
        rpm_resume
        __pm_runtime_resume
        usb_autoresume_device
        usb_remote_wakeup
        hub_event
        process_one_work
        worker_thread
        kthread
        ret_from_fork
        ret_from_fork_asm

And also:

* drivers/net/usb/r8152.c::rtl_work_func_t
* drivers/net/netdevsim/netdev.c::nsim_start_xmit

There is a long history of issues of this kind:

	019edd01d174 ("ath10k: sdio: Add missing BH locking around napi_schdule()")
	330068589389 ("idpf: disable local BH when scheduling napi for marker packets")
	e3d5d70cb483 ("net: lan78xx: fix "softirq work is pending" error")
	e55c27ed9ccf ("mt76: mt7615: add missing bh-disable around rx napi schedule")
	c0182aa98570 ("mt76: mt7915: add missing bh-disable around tx napi enable/schedule")
	970be1dff26d ("mt76: disable BH around napi_schedule() calls")
	019edd01d174 ("ath10k: sdio: Add missing BH locking around napi_schdule()")
	30bfec4fec59 ("can: rx-offload: can_rx_offload_threaded_irq_finish(): add new  function to be called from threaded interrupt")
	e63052a5dd3c ("mlx5e: add add missing BH locking around napi_schdule()")
	83a0c6e ("i40e: Invoke softirqs after napi_reschedule")
	bd4ce94 ("mlx4: Invoke softirqs after napi_reschedule")
	8cf699e ("mlx4: do not call napi_schedule() without care")
	ec13ee8 ("virtio_net: invoke softirqs after __napi_schedule")

This shows that relying on the caller to arrange a proper context for
the softirqs to be handled while calling napi_schedule() is very fragile
and error prone. Also fixing them can also prove challenging if the
caller may be called from different kinds of contexts.

Therefore fix this from napi_schedule() itself with waking up ksoftirqd
when softirqs are raised from task contexts.

Reported-by: Paul Menzel <pmenzel@molgen.mpg.de>
Reported-by: Jakub Kicinski <kuba@kernel.org>
Reported-by: Francois Romieu <romieu@fr.zoreil.com>
Closes: https://lore.kernel.org/lkml/354a2690-9bbf-4ccb-8769-fa94707a9340@molgen.mpg.de/
Cc: Breno Leitao <leitao@debian.org>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250223221708.27130-1-frederic@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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3 participants