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Larysa Zaremba 2f057db2fb ice: protect XDP configuration with a mutex
[ Upstream commit 2504b84057 ]

The main threat to data consistency in ice_xdp() is a possible asynchronous
PF reset. It can be triggered by a user or by TX timeout handler.

XDP setup and PF reset code access the same resources in the following
sections:
* ice_vsi_close() in ice_prepare_for_reset() - already rtnl-locked
* ice_vsi_rebuild() for the PF VSI - not protected
* ice_vsi_open() - already rtnl-locked

With an unfortunate timing, such accesses can result in a crash such as the
one below:

[ +1.999878] ice 0000:b1:00.0: Registered XDP mem model MEM_TYPE_XSK_BUFF_POOL on Rx ring 14
[ +2.002992] ice 0000:b1:00.0: Registered XDP mem model MEM_TYPE_XSK_BUFF_POOL on Rx ring 18
[Mar15 18:17] ice 0000:b1:00.0 ens801f0np0: NETDEV WATCHDOG: CPU: 38: transmit queue 14 timed out 80692736 ms
[ +0.000093] ice 0000:b1:00.0 ens801f0np0: tx_timeout: VSI_num: 6, Q 14, NTC: 0x0, HW_HEAD: 0x0, NTU: 0x0, INT: 0x4000001
[ +0.000012] ice 0000:b1:00.0 ens801f0np0: tx_timeout recovery level 1, txqueue 14
[ +0.394718] ice 0000:b1:00.0: PTP reset successful
[ +0.006184] BUG: kernel NULL pointer dereference, address: 0000000000000098
[ +0.000045] #PF: supervisor read access in kernel mode
[ +0.000023] #PF: error_code(0x0000) - not-present page
[ +0.000023] PGD 0 P4D 0
[ +0.000018] Oops: 0000 [#1] PREEMPT SMP NOPTI
[ +0.000023] CPU: 38 PID: 7540 Comm: kworker/38:1 Not tainted 6.8.0-rc7 #1
[ +0.000031] Hardware name: Intel Corporation S2600WFT/S2600WFT, BIOS SE5C620.86B.02.01.0014.082620210524 08/26/2021
[ +0.000036] Workqueue: ice ice_service_task [ice]
[ +0.000183] RIP: 0010:ice_clean_tx_ring+0xa/0xd0 [ice]
[...]
[ +0.000013] Call Trace:
[ +0.000016] <TASK>
[ +0.000014] ? __die+0x1f/0x70
[ +0.000029] ? page_fault_oops+0x171/0x4f0
[ +0.000029] ? schedule+0x3b/0xd0
[ +0.000027] ? exc_page_fault+0x7b/0x180
[ +0.000022] ? asm_exc_page_fault+0x22/0x30
[ +0.000031] ? ice_clean_tx_ring+0xa/0xd0 [ice]
[ +0.000194] ice_free_tx_ring+0xe/0x60 [ice]
[ +0.000186] ice_destroy_xdp_rings+0x157/0x310 [ice]
[ +0.000151] ice_vsi_decfg+0x53/0xe0 [ice]
[ +0.000180] ice_vsi_rebuild+0x239/0x540 [ice]
[ +0.000186] ice_vsi_rebuild_by_type+0x76/0x180 [ice]
[ +0.000145] ice_rebuild+0x18c/0x840 [ice]
[ +0.000145] ? delay_tsc+0x4a/0xc0
[ +0.000022] ? delay_tsc+0x92/0xc0
[ +0.000020] ice_do_reset+0x140/0x180 [ice]
[ +0.000886] ice_service_task+0x404/0x1030 [ice]
[ +0.000824] process_one_work+0x171/0x340
[ +0.000685] worker_thread+0x277/0x3a0
[ +0.000675] ? preempt_count_add+0x6a/0xa0
[ +0.000677] ? _raw_spin_lock_irqsave+0x23/0x50
[ +0.000679] ? __pfx_worker_thread+0x10/0x10
[ +0.000653] kthread+0xf0/0x120
[ +0.000635] ? __pfx_kthread+0x10/0x10
[ +0.000616] ret_from_fork+0x2d/0x50
[ +0.000612] ? __pfx_kthread+0x10/0x10
[ +0.000604] ret_from_fork_asm+0x1b/0x30
[ +0.000604] </TASK>

The previous way of handling this through returning -EBUSY is not viable,
particularly when destroying AF_XDP socket, because the kernel proceeds
with removal anyway.

There is plenty of code between those calls and there is no need to create
a large critical section that covers all of them, same as there is no need
to protect ice_vsi_rebuild() with rtnl_lock().

Add xdp_state_lock mutex to protect ice_vsi_rebuild() and ice_xdp().

Leaving unprotected sections in between would result in two states that
have to be considered:
1. when the VSI is closed, but not yet rebuild
2. when VSI is already rebuild, but not yet open

The latter case is actually already handled through !netif_running() case,
we just need to adjust flag checking a little. The former one is not as
trivial, because between ice_vsi_close() and ice_vsi_rebuild(), a lot of
hardware interaction happens, this can make adding/deleting rings exit
with an error. Luckily, VSI rebuild is pending and can apply new
configuration for us in a managed fashion.

Therefore, add an additional VSI state flag ICE_VSI_REBUILD_PENDING to
indicate that ice_xdp() can just hot-swap the program.

Also, as ice_vsi_rebuild() flow is touched in this patch, make it more
consistent by deconfiguring VSI when coalesce allocation fails.

Fixes: 2d4238f556 ("ice: Add support for AF_XDP")
Fixes: efc2214b60 ("ice: Add support for XDP")
Reviewed-by: Wojciech Drewek <wojciech.drewek@intel.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Chandan Kumar Rout <chandanx.rout@intel.com>
Signed-off-by: Larysa Zaremba <larysa.zaremba@intel.com>
Reviewed-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-09-12 11:11:34 +02:00
arch riscv: kprobes: Use patch_text_nosync() for insn slots 2024-09-12 11:11:30 +02:00
block block: remove the blk_flush_integrity call in blk_integrity_unregister 2024-09-08 07:54:47 +02:00
certs
crypto crypto: aead,cipher - zeroize key buffer after use 2024-07-11 12:49:04 +02:00
Documentation hwspinlock: Introduce hwspin_lock_bust() 2024-09-08 07:54:43 +02:00
drivers ice: protect XDP configuration with a mutex 2024-09-12 11:11:34 +02:00
fs cifs: Fix FALLOC_FL_ZERO_RANGE to preflush buffered part of target region 2024-09-12 11:11:32 +02:00
include Bluetooth: hci_sync: Introduce hci_cmd_sync_run/hci_cmd_sync_run_once 2024-09-12 11:11:33 +02:00
init rust: fix the default format for CONFIG_{RUSTC,BINDGEN}_VERSION_TEXT 2024-08-29 17:33:29 +02:00
io_uring io_uring: fix io_match_task must_hold 2024-08-03 08:54:41 +02:00
ipc sysctl: treewide: drop unused argument ctl_table_root::set_ownership(table) 2024-08-11 12:47:13 +02:00
kernel bpf, verifier: Correct tail_call_reachable for bpf prog 2024-09-12 11:11:29 +02:00
lib sched/topology: Handle NUMA_NO_NODE in sched_numa_find_nth_cpu() 2024-08-29 17:33:24 +02:00
LICENSES
mm userfaultfd: fix checks for huge PMDs 2024-09-12 11:11:27 +02:00
net Bluetooth: MGMT: Fix not generating command complete for MGMT_OP_DISCONNECT 2024-09-12 11:11:33 +02:00
rust rust: kbuild: fix export of bss symbols 2024-09-12 11:11:32 +02:00
samples bpf: Replace bpf_lpm_trie_key 0-length array with flexible array 2024-08-19 06:04:27 +02:00
scripts rust: work around bindgen 0.69.0 issue 2024-08-29 17:33:29 +02:00
security smack: unix sockets: fix accept()ed socket label 2024-09-12 11:11:29 +02:00
sound ALSA: hda: Add input value sanity checks to HDMI channel map controls 2024-09-12 11:11:29 +02:00
tools selftests: mptcp: join: stop transfer when check is done (part 2.2) 2024-09-08 07:54:35 +02:00
usr
virt KVM: Fix a data race on last_boosted_vcpu in kvm_vcpu_on_spin() 2024-06-27 13:49:11 +02:00
.clang-format
.cocciconfig
.get_maintainer.ignore
.gitattributes
.gitignore
.mailmap
.rustfmt.toml
COPYING
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Kconfig
MAINTAINERS
Makefile Linux 6.6.50 2024-09-08 07:54:49 +02:00
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