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2025-04-04irqdomain: Stop using 'host' for domainJiri Slaby (SUSE)
It is confusing to see 'host' and 'domain' to be used as 'domain'. Given this header is all about domains, switch the remaining 'host' uses to 'domain'. Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20250319092951.37667-5-jirislaby@kernel.org
2025-04-04irqdomain: Rename irq_get_default_host() to irq_get_default_domain()Jiri Slaby (SUSE)
Naming interrupt domains host is confusing at best and the irqdomain code uses both domain and host inconsistently. Therefore rename irq_get_default_host() to irq_get_default_domain(). Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20250319092951.37667-4-jirislaby@kernel.org
2025-04-04irqdomain: Rename irq_set_default_host() to irq_set_default_domain()Jiri Slaby (SUSE)
Naming interrupt domains host is confusing at best and the irqdomain code uses both domain and host inconsistently. Therefore rename irq_set_default_host() to irq_set_default_domain(). Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20250319092951.37667-3-jirislaby@kernel.org
2025-04-04Merge branch 'netlink-specs-rt_addr-fix-problems-revealed-by-c-codegen'Jakub Kicinski
Jakub Kicinski says: ==================== netlink: specs: rt_addr: fix problems revealed by C codegen I put together basic YNL C support for classic netlink. This revealed a few problems in the rt_addr spec. v1: https://lore.kernel.org/20250401012939.2116915-1-kuba@kernel.org ==================== Link: https://patch.msgid.link/20250403013706.2828322-1-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-04-04netlink: specs: rt_route: pull the ifa- prefix out of the namesJakub Kicinski
YAML specs don't normally include the C prefix name in the name of the YAML attr. Remove the ifa- prefix from all attributes in route-attrs and metrics and specify name-prefix instead. This is a bit risky, hopefully there aren't many users out there. Fixes: 023289b4f582 ("doc/netlink: Add spec for rt route messages") Reviewed-by: Donald Hunter <donald.hunter@gmail.com> Link: https://patch.msgid.link/20250403013706.2828322-5-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-04-04netlink: specs: rt_addr: pull the ifa- prefix out of the namesJakub Kicinski
YAML specs don't normally include the C prefix name in the name of the YAML attr. Remove the ifa- prefix from all attributes in addr-attrs and specify name-prefix instead. This is a bit risky, hopefully there aren't many users out there. Fixes: dfb0f7d9d979 ("doc/netlink: Add spec for rt addr messages") Reviewed-by: Donald Hunter <donald.hunter@gmail.com> Link: https://patch.msgid.link/20250403013706.2828322-4-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-04-04netlink: specs: rt_addr: fix get multi command nameJakub Kicinski
Command names should match C defines, codegens may depend on it. Reviewed-by: Jacob Keller <jacob.e.keller@intel.com> Fixes: 4f280376e531 ("selftests/net: Add selftest for IPv4 RTM_GETMULTICAST support") Reviewed-by: Donald Hunter <donald.hunter@gmail.com> Link: https://patch.msgid.link/20250403013706.2828322-3-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-04-04netlink: specs: rt_addr: fix the spec format / schema failuresJakub Kicinski
The spec is mis-formatted, schema validation says: Failed validating 'type' in schema['properties']['operations']['properties']['list']['items']['properties']['dump']['properties']['request']['properties']['value']: {'minimum': 0, 'type': 'integer'} On instance['operations']['list'][3]['dump']['request']['value']: '58 - ifa-family' The ifa-family clearly wants to be part of an attribute list. Reviewed-by: Jacob Keller <jacob.e.keller@intel.com> Reviewed-by: Donald Hunter <donald.hunter@gmail.com> Reviewed-by: Yuyang Huang <yuyanghuang@google.com> Fixes: 4f280376e531 ("selftests/net: Add selftest for IPv4 RTM_GETMULTICAST support") Link: https://patch.msgid.link/20250403013706.2828322-2-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-04-04Merge branch 'net-make-memory-provider-install-close-paths-more-common'Jakub Kicinski
Jakub Kicinski says: ==================== net: make memory provider install / close paths more common We seem to be fixing bugs in config path for devmem which also exist in the io_uring ZC path. Let's try to make the two paths more common, otherwise this is bound to keep happening. Found by code inspection and compile tested only. v1: https://lore.kernel.org/20250331194201.2026422-1-kuba@kernel.org ==================== Link: https://patch.msgid.link/20250403013405.2827250-1-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-04-04net: avoid false positive warnings in __net_mp_close_rxq()Jakub Kicinski
Commit under Fixes solved the problem of spurious warnings when we uninstall an MP from a device while its down. The __net_mp_close_rxq() which is used by io_uring was not fixed. Move the fix over and reuse __net_mp_close_rxq() in the devmem path. Acked-by: Stanislav Fomichev <sdf@fomichev.me> Fixes: a70f891e0fa0 ("net: devmem: do not WARN conditionally after netdev_rx_queue_restart()") Reviewed-by: Mina Almasry <almasrymina@google.com> Link: https://patch.msgid.link/20250403013405.2827250-3-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-04-04net: move mp dev config validation to __net_mp_open_rxq()Jakub Kicinski
devmem code performs a number of safety checks to avoid having to reimplement all of them in the drivers. Move those to __net_mp_open_rxq() and reuse that function for binding to make sure that io_uring ZC also benefits from them. While at it rename the queue ID variable to rxq_idx in __net_mp_open_rxq(), we touch most of the relevant lines. The XArray insertion is reordered after the netdev_rx_queue_restart() call, otherwise we'd need to duplicate the queue index check or risk inserting an invalid pointer. The XArray allocation failures should be extremely rare. Reviewed-by: Mina Almasry <almasrymina@google.com> Acked-by: Stanislav Fomichev <sdf@fomichev.me> Fixes: 6e18ed929d3b ("net: add helpers for setting a memory provider on an rx queue") Link: https://patch.msgid.link/20250403013405.2827250-2-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-04-04net: ibmveth: make veth_pool_store stop hangingDave Marquardt
v2: - Created a single error handling unlock and exit in veth_pool_store - Greatly expanded commit message with previous explanatory-only text Summary: Use rtnl_mutex to synchronize veth_pool_store with itself, ibmveth_close and ibmveth_open, preventing multiple calls in a row to napi_disable. Background: Two (or more) threads could call veth_pool_store through writing to /sys/devices/vio/30000002/pool*/*. You can do this easily with a little shell script. This causes a hang. I configured LOCKDEP, compiled ibmveth.c with DEBUG, and built a new kernel. I ran this test again and saw: Setting pool0/active to 0 Setting pool1/active to 1 [ 73.911067][ T4365] ibmveth 30000002 eth0: close starting Setting pool1/active to 1 Setting pool1/active to 0 [ 73.911367][ T4366] ibmveth 30000002 eth0: close starting [ 73.916056][ T4365] ibmveth 30000002 eth0: close complete [ 73.916064][ T4365] ibmveth 30000002 eth0: open starting [ 110.808564][ T712] systemd-journald[712]: Sent WATCHDOG=1 notification. [ 230.808495][ T712] systemd-journald[712]: Sent WATCHDOG=1 notification. [ 243.683786][ T123] INFO: task stress.sh:4365 blocked for more than 122 seconds. [ 243.683827][ T123] Not tainted 6.14.0-01103-g2df0c02dab82-dirty #8 [ 243.683833][ T123] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 243.683838][ T123] task:stress.sh state:D stack:28096 pid:4365 tgid:4365 ppid:4364 task_flags:0x400040 flags:0x00042000 [ 243.683852][ T123] Call Trace: [ 243.683857][ T123] [c00000000c38f690] [0000000000000001] 0x1 (unreliable) [ 243.683868][ T123] [c00000000c38f840] [c00000000001f908] __switch_to+0x318/0x4e0 [ 243.683878][ T123] [c00000000c38f8a0] [c000000001549a70] __schedule+0x500/0x12a0 [ 243.683888][ T123] [c00000000c38f9a0] [c00000000154a878] schedule+0x68/0x210 [ 243.683896][ T123] [c00000000c38f9d0] [c00000000154ac80] schedule_preempt_disabled+0x30/0x50 [ 243.683904][ T123] [c00000000c38fa00] [c00000000154dbb0] __mutex_lock+0x730/0x10f0 [ 243.683913][ T123] [c00000000c38fb10] [c000000001154d40] napi_enable+0x30/0x60 [ 243.683921][ T123] [c00000000c38fb40] [c000000000f4ae94] ibmveth_open+0x68/0x5dc [ 243.683928][ T123] [c00000000c38fbe0] [c000000000f4aa20] veth_pool_store+0x220/0x270 [ 243.683936][ T123] [c00000000c38fc70] [c000000000826278] sysfs_kf_write+0x68/0xb0 [ 243.683944][ T123] [c00000000c38fcb0] [c0000000008240b8] kernfs_fop_write_iter+0x198/0x2d0 [ 243.683951][ T123] [c00000000c38fd00] [c00000000071b9ac] vfs_write+0x34c/0x650 [ 243.683958][ T123] [c00000000c38fdc0] [c00000000071bea8] ksys_write+0x88/0x150 [ 243.683966][ T123] [c00000000c38fe10] [c0000000000317f4] system_call_exception+0x124/0x340 [ 243.683973][ T123] [c00000000c38fe50] [c00000000000d05c] system_call_vectored_common+0x15c/0x2ec ... [ 243.684087][ T123] Showing all locks held in the system: [ 243.684095][ T123] 1 lock held by khungtaskd/123: [ 243.684099][ T123] #0: c00000000278e370 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x50/0x248 [ 243.684114][ T123] 4 locks held by stress.sh/4365: [ 243.684119][ T123] #0: c00000003a4cd3f8 (sb_writers#3){.+.+}-{0:0}, at: ksys_write+0x88/0x150 [ 243.684132][ T123] #1: c000000041aea888 (&of->mutex#2){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x154/0x2d0 [ 243.684143][ T123] #2: c0000000366fb9a8 (kn->active#64){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x160/0x2d0 [ 243.684155][ T123] #3: c000000035ff4cb8 (&dev->lock){+.+.}-{3:3}, at: napi_enable+0x30/0x60 [ 243.684166][ T123] 5 locks held by stress.sh/4366: [ 243.684170][ T123] #0: c00000003a4cd3f8 (sb_writers#3){.+.+}-{0:0}, at: ksys_write+0x88/0x150 [ 243.684183][ T123] #1: c00000000aee2288 (&of->mutex#2){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x154/0x2d0 [ 243.684194][ T123] #2: c0000000366f4ba8 (kn->active#64){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x160/0x2d0 [ 243.684205][ T123] #3: c000000035ff4cb8 (&dev->lock){+.+.}-{3:3}, at: napi_disable+0x30/0x60 [ 243.684216][ T123] #4: c0000003ff9bbf18 (&rq->__lock){-.-.}-{2:2}, at: __schedule+0x138/0x12a0 From the ibmveth debug, two threads are calling veth_pool_store, which calls ibmveth_close and ibmveth_open. Here's the sequence: T4365 T4366 ----------------- ----------------- --------- veth_pool_store veth_pool_store ibmveth_close ibmveth_close napi_disable napi_disable ibmveth_open napi_enable <- HANG ibmveth_close calls napi_disable at the top and ibmveth_open calls napi_enable at the top. https://docs.kernel.org/networking/napi.html]] says The control APIs are not idempotent. Control API calls are safe against concurrent use of datapath APIs but an incorrect sequence of control API calls may result in crashes, deadlocks, or race conditions. For example, calling napi_disable() multiple times in a row will deadlock. In the normal open and close paths, rtnl_mutex is acquired to prevent other callers. This is missing from veth_pool_store. Use rtnl_mutex in veth_pool_store fixes these hangs. Signed-off-by: Dave Marquardt <davemarq@linux.ibm.com> Fixes: 860f242eb534 ("[PATCH] ibmveth change buffer pools dynamically") Reviewed-by: Nick Child <nnac123@linux.ibm.com> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://patch.msgid.link/20250402154403.386744-1-davemarq@linux.ibm.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-04-04arcnet: Add NULL check in com20020pci_probe()Henry Martin
devm_kasprintf() returns NULL when memory allocation fails. Currently, com20020pci_probe() does not check for this case, which results in a NULL pointer dereference. Add NULL check after devm_kasprintf() to prevent this issue and ensure no resources are left allocated. Fixes: 6b17a597fc2f ("arcnet: restoring support for multiple Sohard Arcnet cards") Signed-off-by: Henry Martin <bsdhenrymartin@gmail.com> Link: https://patch.msgid.link/20250402135036.44697-1-bsdhenrymartin@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-04-04Merge branch 'ipv6-multipath-routing-fixes'Jakub Kicinski
Ido Schimmel says: ==================== ipv6: Multipath routing fixes This patchset contains two fixes for IPv6 multipath routing. See the commit messages for more details. ==================== Link: https://patch.msgid.link/20250402114224.293392-1-idosch@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-04-04ipv6: Do not consider link down nexthops in path selectionIdo Schimmel
Nexthops whose link is down are not supposed to be considered during path selection when the "ignore_routes_with_linkdown" sysctl is set. This is done by assigning them a negative region boundary. However, when comparing the computed hash (unsigned) with the region boundary (signed), the negative region boundary is treated as unsigned, resulting in incorrect nexthop selection. Fix by treating the computed hash as signed. Note that the computed hash is always in range of [0, 2^31 - 1]. Fixes: 3d709f69a3e7 ("ipv6: Use hash-threshold instead of modulo-N") Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Link: https://patch.msgid.link/20250402114224.293392-3-idosch@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-04-04ipv6: Start path selection from the first nexthopIdo Schimmel
Cited commit transitioned IPv6 path selection to use hash-threshold instead of modulo-N. With hash-threshold, each nexthop is assigned a region boundary in the multipath hash function's output space and a nexthop is chosen if the calculated hash is smaller than the nexthop's region boundary. Hash-threshold does not work correctly if path selection does not start with the first nexthop. For example, if fib6_select_path() is always passed the last nexthop in the group, then it will always be chosen because its region boundary covers the entire hash function's output space. Fix this by starting the selection process from the first nexthop and do not consider nexthops for which rt6_score_route() provided a negative score. Fixes: 3d709f69a3e7 ("ipv6: Use hash-threshold instead of modulo-N") Reported-by: Stanislav Fomichev <stfomichev@gmail.com> Closes: https://lore.kernel.org/netdev/Z9RIyKZDNoka53EO@mini-arch/ Signed-off-by: Ido Schimmel <idosch@nvidia.com> Link: https://patch.msgid.link/20250402114224.293392-2-idosch@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-04-04usbnet:fix NPE during rx_completeYing Lu
Missing usbnet_going_away Check in Critical Path. The usb_submit_urb function lacks a usbnet_going_away validation, whereas __usbnet_queue_skb includes this check. This inconsistency creates a race condition where: A URB request may succeed, but the corresponding SKB data fails to be queued. Subsequent processes: (e.g., rx_complete → defer_bh → __skb_unlink(skb, list)) attempt to access skb->next, triggering a NULL pointer dereference (Kernel Panic). Fixes: 04e906839a05 ("usbnet: fix cyclical race on disconnect with work queue") Cc: stable@vger.kernel.org Signed-off-by: Ying Lu <luying1@xiaomi.com> Link: https://patch.msgid.link/4c9ef2efaa07eb7f9a5042b74348a67e5a3a7aea.1743584159.git.luying1@xiaomi.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-04-04net: octeontx2: Handle XDP_ABORTED and XDP invalid as XDP_DROPLorenzo Bianconi
In the current implementation octeontx2 manages XDP_ABORTED and XDP invalid as XDP_PASS forwarding the skb to the networking stack. Align the behaviour to other XDP drivers handling XDP_ABORTED and XDP invalid as XDP_DROP. Please note this patch has just compile tested. Fixes: 06059a1a9a4a5 ("octeontx2-pf: Add XDP support to netdev PF") Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> Link: https://patch.msgid.link/20250401-octeontx2-xdp-abort-fix-v1-1-f0587c35a0b9@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-04-04Merge tag 'x86-urgent-2025-04-04' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Ingo Molnar: - Fix a performance regression on AMD iGPU and dGPU drivers, related to the unintended activation of DMA bounce buffers that regressed game performance if KASLR disturbed things just enough - Fix a copy_user_generic() performance regression on certain older non-FSRM/ERMS CPUs - Fix a Clang build warning due to a semantic merge conflict the Kunit tree generated with the x86 tree - Fix FRED related system hang during S4 resume - Remove an unused API * tag 'x86-urgent-2025-04-04' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/fred: Fix system hang during S4 resume with FRED enabled x86/platform/iosf_mbi: Remove unused iosf_mbi_unregister_pmic_bus_access_notifier() x86/mm/init: Handle the special case of device private pages in add_pages(), to not increase max_pfn and trigger dma_addressing_limited() bounce buffers x86/tools: Drop duplicate unlikely() definition in insn_decoder_test.c x86/uaccess: Improve performance by aligning writes to 8 bytes in copy_user_generic(), on non-FSRM/ERMS CPUs
2025-04-04Merge tag 'sound-fix-6.15-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound Pull sound fixes from Takashi Iwai: "A collection of device-specific fixes that have been gathered since the previous pull: - A few more HD-audio quirks and fixups - A series of Qualcomm AudioReach fixes - Various small fixes for ASoC rt5665, WSA, SOF and Cirrus" * tag 'sound-fix-6.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: ALSA: hda/realtek: Fix built-in mic on another ASUS VivoBook model ALSA: hda/realtek - Support mute led function for HP platform ASoC: imx-card: Add NULL check in imx_card_probe() ASoC: codecs: rt5665: Fix some error handling paths in rt5665_probe() ASoC: q6apm-dai: make use of q6apm_get_hw_pointer ASoC: qdsp6: q6apm-dai: fix capture pipeline overruns. ASoC: qdsp6: q6apm-dai: set 10 ms period and buffer alignment. ASoC: q6apm: add q6apm_get_hw_pointer helper ASoC: q6apm-dai: schedule all available frames to avoid dsp under-runs ASoC: SOF: hda/ptl: Move mic privacy change notification sending to a work ALSA/hda: intel-sdw-acpi: Remove (explicitly) unused header ALSA: hda/realtek: Enable Mute LED on HP OMEN 16 Laptop xd000xx ALSA: hda/tas2781: Upgrade calibratd-data writing code to support Alpha and Beta dsp firmware ASoC: qdsp6: q6asm-dai: fix q6asm_dai_compr_set_params error path ALSA: hda/realtek: Fix built-in mic breakage on ASUS VivoBook X515JA ASoC: sma1307: Fix error handling in sma1307_setting_loaded() ASoC: codecs: wsa884x: Correct VI sense channel mask ASoC: codecs: wsa883x: Correct VI sense channel mask firmware: cs_dsp: Ensure cs_dsp_load[_coeff]() returns 0 on success
2025-04-04Merge tag 'omap-for-v6.14/drivers-signed' of ↵Arnd Bergmann
https://git.kernel.org/pub/scm/linux/kernel/git/khilman/linux-omap into soc/drivers-2 arm/omap: drivers: updates for v6.14 * tag 'omap-for-v6.14/drivers-signed' of https://git.kernel.org/pub/scm/linux/kernel/git/khilman/linux-omap: Input: tsc2007 - accept standard properties
2025-04-04Merge tag 'soc_fsl-6.15-1' of https://github.com/chleroy/linux into ↵Arnd Bergmann
soc/drivers-2 FSL SOC Changes for 6.15: - irqdomain cleanups from Jiry - Add Ioana as Maintainer of fsl-mc bus and remove Laurentiu and Stuart - Remove deadcode from fsl-mc bus * tag 'soc_fsl-6.15-1' of https://github.com/chleroy/linux: bus: fsl-mc: Remove deadcode MAINTAINERS: add the linuppc-dev list to the fsl-mc bus entry MAINTAINERS: fix nonexistent dtbinding file name MAINTAINERS: add myself as maintainer for the fsl-mc bus irqdomain: soc: Switch to irq_find_mapping()
2025-04-04Merge branch 'kvm-pi-fix-lockdep' into HEADPaolo Bonzini
2025-04-04Merge branch 'kvm-6.15-rc2-fixes' into HEADPaolo Bonzini
2025-04-04Merge branch 'kvm-6.15-rc2-cleanups' into HEADPaolo Bonzini
2025-04-04KVM: VMX: Use separate subclasses for PI wakeup lock to squash false positiveYan Zhao
Use a separate subclass when acquiring KVM's per-CPU posted interrupts wakeup lock in the scheduled out path, i.e. when adding a vCPU on the list of vCPUs to wake, to workaround a false positive deadlock. Chain exists of: &p->pi_lock --> &rq->__lock --> &per_cpu(wakeup_vcpus_on_cpu_lock, cpu) Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&per_cpu(wakeup_vcpus_on_cpu_lock, cpu)); lock(&rq->__lock); lock(&per_cpu(wakeup_vcpus_on_cpu_lock, cpu)); lock(&p->pi_lock); *** DEADLOCK *** In the wakeup handler, the callchain is *always*: sysvec_kvm_posted_intr_wakeup_ipi() | --> pi_wakeup_handler() | --> kvm_vcpu_wake_up() | --> try_to_wake_up(), and the lock order is: &per_cpu(wakeup_vcpus_on_cpu_lock, cpu) --> &p->pi_lock. For the schedule out path, the callchain is always (for all intents and purposes; if the kernel is preemptible, kvm_sched_out() can be called from something other than schedule(), but the beginning of the callchain will be the same point in vcpu_block()): vcpu_block() | --> schedule() | --> kvm_sched_out() | --> vmx_vcpu_put() | --> vmx_vcpu_pi_put() | --> pi_enable_wakeup_handler() and the lock order is: &rq->__lock --> &per_cpu(wakeup_vcpus_on_cpu_lock, cpu) I.e. lockdep sees AB+BC ordering for schedule out, and CA ordering for wakeup, and complains about the A=>C versus C=>A inversion. In practice, deadlock can't occur between schedule out and the wakeup handler as they are mutually exclusive. The entirely of the schedule out code that runs with the problematic scheduler locks held, does so with IRQs disabled, i.e. can't run concurrently with the wakeup handler. Use a subclass instead disabling lockdep entirely, and tell lockdep that both subclasses are being acquired when loading a vCPU, as the sched_out and sched_in paths are NOT mutually exclusive, e.g. CPU 0 CPU 1 --------------- --------------- vCPU0 sched_out vCPU1 sched_in vCPU1 sched_out vCPU 0 sched_in where vCPU0's sched_in may race with vCPU1's sched_out, on CPU 0's wakeup list+lock. Signed-off-by: Yan Zhao <yan.y.zhao@intel.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com> Message-ID: <20250401154727.835231-3-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-04-04KVM: VMX: Assert that IRQs are disabled when putting vCPU on PI wakeup listSean Christopherson
Assert that IRQs are already disabled when putting a vCPU on a CPU's PI wakeup list, as opposed to saving/disabling+restoring IRQs. KVM relies on IRQs being disabled until the vCPU task is fully scheduled out, i.e. until the scheduler has dropped all of its per-CPU locks (e.g. for the runqueue), as attempting to wake the task while it's being scheduled out could lead to deadlock. Signed-off-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com> Reviewed-by: Yan Zhao <yan.y.zhao@intel.com> Message-ID: <20250401154727.835231-2-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-04-04KVM: x86: Explicitly zero-initialize on-stack CPUID unionsSean Christopherson
Explicitly zero/empty-initialize the unions used for PMU related CPUID entries, instead of manually zeroing all fields (hopefully), or in the case of 0x80000022, relying on the compiler to clobber the uninitialized bitfields. Signed-off-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Jim Mattson <jmattson@google.com> Message-ID: <20250315024102.2361628-1-seanjc@google.com> Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-04-04KVM: Allow building irqbypass.ko as as module when kvm.ko is a moduleSean Christopherson
Convert HAVE_KVM_IRQ_BYPASS into a tristate so that selecting IRQ_BYPASS_MANAGER follows KVM={m,y}, i.e. doesn't force irqbypass.ko to be built-in. Note, PPC allows building KVM as a module, but selects HAVE_KVM_IRQ_BYPASS from a boolean Kconfig, i.e. KVM PPC unnecessarily forces irqbpass.ko to be built-in. But that flaw is a longstanding PPC specific issue. Fixes: 61df71ee992d ("kvm: move "select IRQ_BYPASS_MANAGER" to common code") Cc: stable@vger.kernel.org Signed-off-by: Sean Christopherson <seanjc@google.com> Message-ID: <20250315024623.2363994-1-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-04-04KVM: x86/mmu: Wrap sanity check on number of TDP MMU pages with KVM_PROVE_MMUSean Christopherson
Wrap the TDP MMU page counter in CONFIG_KVM_PROVE_MMU so that the sanity check is omitted from production builds, and more importantly to remove the atomic accesses to account pages. A one-off memory leak in production is relatively uninteresting, and a WARN_ON won't help mitigate a systemic issue; it's as much about helping triage memory leaks as it is about detecting them in the first place, and doesn't magically stop the leaks. I.e. production environments will be quite sad if a severe KVM bug escapes, regardless of whether or not KVM WARNs. Signed-off-by: Sean Christopherson <seanjc@google.com> Message-ID: <20250315023448.2358456-1-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-04-04KVM: selftests: Add option to rseq test to override /dev/cpu_dma_latencySean Christopherson
Add a "-l <latency>" param to the rseq test so that the user can override /dev/cpu_dma_latency, as described by the test's suggested workaround for not being able to complete enough migrations. cpu_dma_latency is not a normal file, even as far as procfs files go. Writes to cpu_dma_latency only persist so long as the file is open, e.g. so that the kernel automatically reverts back to a power-optimized state once the sensitive workload completes. Provide the necessary functionality instead of effectively forcing the user to write a non-obvious wrapper. Cc: Dongsheng Zhang <dongsheng.x.zhang@intel.com> Cc: Zide Chen <zide.chen@intel.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Message-ID: <20250401142238.819487-1-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-04-04KVM: x86: Acquire SRCU in KVM_GET_MP_STATE to protect guest memory accessesSean Christopherson
Acquire a lock on kvm->srcu when userspace is getting MP state to handle a rather extreme edge case where "accepting" APIC events, i.e. processing pending INIT or SIPI, can trigger accesses to guest memory. If the vCPU is in L2 with INIT *and* a TRIPLE_FAULT request pending, then getting MP state will trigger a nested VM-Exit by way of ->check_nested_events(), and emuating the nested VM-Exit can access guest memory. The splat was originally hit by syzkaller on a Google-internal kernel, and reproduced on an upstream kernel by hacking the triple_fault_event_test selftest to stuff a pending INIT, store an MSR on VM-Exit (to generate a memory access on VMX), and do vcpu_mp_state_get() to trigger the scenario. ============================= WARNING: suspicious RCU usage 6.14.0-rc3-b112d356288b-vmx/pi_lockdep_false_pos-lock #3 Not tainted ----------------------------- include/linux/kvm_host.h:1058 suspicious rcu_dereference_check() usage! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 1 lock held by triple_fault_ev/1256: #0: ffff88810df5a330 (&vcpu->mutex){+.+.}-{4:4}, at: kvm_vcpu_ioctl+0x8b/0x9a0 [kvm] stack backtrace: CPU: 11 UID: 1000 PID: 1256 Comm: triple_fault_ev Not tainted 6.14.0-rc3-b112d356288b-vmx #3 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 Call Trace: <TASK> dump_stack_lvl+0x7f/0x90 lockdep_rcu_suspicious+0x144/0x190 kvm_vcpu_gfn_to_memslot+0x156/0x180 [kvm] kvm_vcpu_read_guest+0x3e/0x90 [kvm] read_and_check_msr_entry+0x2e/0x180 [kvm_intel] __nested_vmx_vmexit+0x550/0xde0 [kvm_intel] kvm_check_nested_events+0x1b/0x30 [kvm] kvm_apic_accept_events+0x33/0x100 [kvm] kvm_arch_vcpu_ioctl_get_mpstate+0x30/0x1d0 [kvm] kvm_vcpu_ioctl+0x33e/0x9a0 [kvm] __x64_sys_ioctl+0x8b/0xb0 do_syscall_64+0x6c/0x170 entry_SYSCALL_64_after_hwframe+0x4b/0x53 </TASK> Cc: stable@vger.kernel.org Signed-off-by: Sean Christopherson <seanjc@google.com> Message-ID: <20250401150504.829812-1-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-04-04Documentation: kvm: remove KVM_CAP_MIPS_TEPaolo Bonzini
Trap and emulate virtualization is not available anymore for MIPS. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-04-04Documentation: kvm: organize capabilities in the right sectionPaolo Bonzini
Categorize the capabilities correctly. Section 6 is for enabled vCPU capabilities; section 7 is for enabled VM capabilities; section 8 is for informational ones. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-04-04Documentation: kvm: fix some definition listsPaolo Bonzini
Ensure that they have a ":" in front of the defined item. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-04-04Documentation: kvm: drop "Capability" heading from capabilitiesPaolo Bonzini
It is redundant, and sometimes wrong. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-04-04Documentation: kvm: give correct name for KVM_CAP_SPAPR_MULTITCEPaolo Bonzini
The capability is incorrectly called KVM_CAP_PPC_MULTITCE in the documentation. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-04-04Documentation: KVM: KVM_GET_SUPPORTED_CPUID now exposes TSC_DEADLINEPaolo Bonzini
TSC_DEADLINE is now advertised unconditionally by KVM_GET_SUPPORTED_CPUID, since commit 9be4ec35d668 ("KVM: x86: Advertise TSC_DEADLINE_TIMER in KVM_GET_SUPPORTED_CPUID", 2024-12-18). Adjust the documentation to reflect the new behavior. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Sean Christopherson <seanjc@google.com> Message-ID: <20250331150550.510320-1-pbonzini@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-04-04selftests: kvm: list once tests that are valid on all architecturesPaolo Bonzini
Several tests cover infrastructure from virt/kvm/ and userspace APIs that have only minimal requirements from architecture-specific code. As such, they are available on all architectures that have libkvm support, and this presumably will apply also in the future (for example if loongarch gets selftests support). Put them in a separate variable and list them only once. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Message-ID: <20250401141327.785520-1-pbonzini@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-04-04selftests: kvm: bring list of exit reasons up to datePaolo Bonzini
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Message-ID: <20250331221851.614582-1-pbonzini@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-04-04selftests: kvm: revamp MONITOR/MWAIT testsPaolo Bonzini
Run each testcase in a separate VMs to cover more possibilities; move WRMSR close to MONITOR/MWAIT to test updating CPUID bits while in the VM. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-04-03Merge tag 'pull-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfsLinus Torvalds
Pull dcache fixes from Al Viro: "Fixes for bugs caught as part of tree-in-dcache work. Mostly dentry refcount mishandling" * tag 'pull-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: hypfs_create_cpu_files(): add missing check for hypfs_mkdir() failure qibfs: fix _another_ leak spufs: fix a leak in spufs_create_context() spufs: fix gang directory lifetimes spufs: fix a leak on spufs_new_file() failure
2025-04-03selftests: ublk: fix test_stripe_04Ming Lei
Commit 57ed58c13256 ("selftests: ublk: enable zero copy for stripe target") added test entry of test_stripe_04, but forgot to add the test script. So fix the test by adding the script file. Reported-by: Uday Shankar <ushankar@purestorage.com> Signed-off-by: Ming Lei <ming.lei@redhat.com> Reviewed-by: Uday Shankar <ushankar@purestorage.com> Link: https://lore.kernel.org/r/20250404001849.1443064-1-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-04-03Merge tag 'nf-25-04-03' of ↵Jakub Kicinski
git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf Pablo Neira Ayuso says: ==================== Netfilter fixes for net The following batch contains Netfilter fixes for net: 1) conncount incorrectly removes element for non-dynamic sets, these elements represent a static control plane configuration, leave them in place. 2) syzbot found a way to unregister a basechain that has been never registered from the chain update path, fix from Florian Westphal. 3) Fix incorrect pointer arithmetics in geneve support for tunnel, from Lin Ma. * tag 'nf-25-04-03' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf: netfilter: nft_tunnel: fix geneve_opt type confusion addition netfilter: nf_tables: don't unregister hook when table is dormant netfilter: nft_set_hash: GC reaps elements with conncount for dynamic sets only ==================== Link: https://patch.msgid.link/20250403115752.19608-1-pablo@netfilter.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-04-03Merge tag 'v6.15rc-part2-ksmbd-server-fixes' of git://git.samba.org/ksmbdLinus Torvalds
Pull smb server fixes from Steve French: "Four ksmbd SMB3 server fixes, all also for stable" * tag 'v6.15rc-part2-ksmbd-server-fixes' of git://git.samba.org/ksmbd: ksmbd: fix null pointer dereference in alloc_preauth_hash() ksmbd: validate zero num_subauth before sub_auth is accessed ksmbd: fix overflow in dacloffset bounds check ksmbd: fix session use-after-free in multichannel connection
2025-04-03Merge tag 'trace-ringbuffer-v6.15-3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull ring-buffer updates from Steven Rostedt: "Persistent buffer cleanups and simplifications. It was mistaken that the physical memory returned from "reserve_mem" had to be vmap()'d to get to it from a virtual address. But reserve_mem already maps the memory to the virtual address of the kernel so a simple phys_to_virt() can be used to get to the virtual address from the physical memory returned by "reserve_mem". With this new found knowledge, the code can be cleaned up and simplified. - Enforce that the persistent memory is page aligned As the buffers using the persistent memory are all going to be mapped via pages, make sure that the memory given to the tracing infrastructure is page aligned. If it is not, it will print a warning and fail to map the buffer. - Use phys_to_virt() to get the virtual address from reserve_mem Instead of calling vmap() on the physical memory returned from "reserve_mem", use phys_to_virt() instead. As the memory returned by "memmap" or any other means where a physical address is given to the tracing infrastructure, it still needs to be vmap(). Since this memory can never be returned back to the buddy allocator nor should it ever be memmory mapped to user space, flag this buffer and up the ref count. The ref count will keep it from ever being freed, and the flag will prevent it from ever being memory mapped to user space. - Use vmap_page_range() for memmap virtual address mapping For the memmap buffer, instead of allocating an array of struct pages, assigning them to the contiguous phsycial memory and then passing that to vmap(), use vmap_page_range() instead - Replace flush_dcache_folio() with flush_kernel_vmap_range() Instead of calling virt_to_folio() and passing that to flush_dcache_folio(), just call flush_kernel_vmap_range() directly. This also fixes a bug where if a subbuffer was bigger than PAGE_SIZE only the PAGE_SIZE portion would be flushed" * tag 'trace-ringbuffer-v6.15-3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: ring-buffer: Use flush_kernel_vmap_range() over flush_dcache_folio() tracing: Use vmap_page_range() to map memmap ring buffer tracing: Have reserve_mem use phys_to_virt() and separate from memmap buffer tracing: Enforce the persistent ring buffer to be page aligned
2025-04-03Merge tag 'block-6.15-20250403' of git://git.kernel.dk/linuxLinus Torvalds
Pull more block updates from Jens Axboe: - NVMe pull request via Keith: - PCI endpoint target cleanup (Damien) - Early import for uring_cmd fixed buffer (Caleb) - Multipath documentation and notification improvements (John) - Invalid pci sq doorbell write fix (Maurizio) - Queue init locking fix - Remove dead nsegs parameter from blk_mq_get_new_requests() * tag 'block-6.15-20250403' of git://git.kernel.dk/linux: block: don't grab elevator lock during queue initialization nvme-pci: skip nvme_write_sq_db on empty rqlist nvme-multipath: change the NVME_MULTIPATH config option nvme: update the multipath warning in nvme_init_ns_head nvme/ioctl: move fixed buffer lookup to nvme_uring_cmd_io() nvme/ioctl: move blk_mq_free_request() out of nvme_map_user_request() nvme/ioctl: don't warn on vectorized uring_cmd with fixed buffer nvmet: pci-epf: Keep completion queues mapped block: remove unused nseg parameter
2025-04-03Merge branch '1GbE' of ↵Jakub Kicinski
git://git.kernel.org/pub/scm/linux/kernel/git/tnguy/net-queue Tony Nguyen says: ==================== Intel Wired LAN Driver Updates 2025-04-02 (igc, e1000e, ixgbe, idpf) For igc: Joe Damato removes unmapping of XSK queues from NAPI instance. Zdenek Bouska swaps condition checks/call to prevent AF_XDP Tx drops with low budget value. For e1000e: Vitaly adjusts Kumeran interface configuration to prevent MDI errors. For ixgbe: Piotr clears PHY high values on media type detection to ensure stale values are not used. For idpf: Emil adjusts shutdown calls to prevent NULL pointer dereference. * '1GbE' of git://git.kernel.org/pub/scm/linux/kernel/git/tnguy/net-queue: idpf: fix adapter NULL pointer dereference on reboot ixgbe: fix media type detection for E610 device e1000e: change k1 configuration on MTP and later platforms igc: Fix TX drops in XDP ZC igc: Fix XSK queue NAPI ID mapping ==================== Link: https://patch.msgid.link/20250402173900.1957261-1-anthony.l.nguyen@intel.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-04-03Merge tag 'io_uring-6.15-20250403' of git://git.kernel.dk/linuxLinus Torvalds
Pull more io_uring updates from Jens Axboe: "Set of fixes/updates for io_uring that should go into this release. The ublk bits could've gone via either tree - usually I put them in block, but they got a bit mixed this series with the zero-copy supported that ended up dipping into both trees. This contains: - Fix for sendmsg zc, include in pinned pages accounting like we do for the other zc types - Series for ublk fixing request aborting, doing various little cleanups, fixing some zc issues, and adding queue_rqs support - Another ublk series doing some code cleanups - Series cleaning up the io_uring send path, mostly in preparation for registered buffers - Series doing little MSG_RING cleanups - Fix for the newly added zc rx, fixing len being 0 for the last invocation of the callback - Add vectored registered buffer support for ublk. With that, then ublk also supports this feature in the kernel revision where it could generically introduced for rw/net - A bunch of selftest additions for ublk. This is the majority of the diffstat - Silence a KCSAN data race warning for io-wq - Various little cleanups and fixes" * tag 'io_uring-6.15-20250403' of git://git.kernel.dk/linux: (44 commits) io_uring: always do atomic put from iowq selftests: ublk: enable zero copy for stripe target io_uring: support vectored kernel fixed buffer block: add for_each_mp_bvec() io_uring: add validate_fixed_range() for validate fixed buffer selftests: ublk: kublk: fix an error log line selftests: ublk: kublk: use ioctl-encoded opcodes io_uring/zcrx: return early from io_zcrx_recv_skb if readlen is 0 io_uring/net: avoid import_ubuf for regvec send io_uring/rsrc: check size when importing reg buffer io_uring: cleanup {g,s]etsockopt sqe reading io_uring: hide caches sqes from drivers io_uring: make zcrx depend on CONFIG_IO_URING io_uring: add req flag invariant build assertion Documentation: ublk: remove dead footnote selftests: ublk: specify io_cmd_buf pointer type ublk: specify io_cmd_buf pointer type io_uring: don't pass ctx to tw add remote helper io_uring/msg: initialise msg request opcode io_uring/msg: rename io_double_lock_ctx() ...
2025-04-03net: fix geneve_opt length integer overflowLin Ma
struct geneve_opt uses 5 bit length for each single option, which means every vary size option should be smaller than 128 bytes. However, all current related Netlink policies cannot promise this length condition and the attacker can exploit a exact 128-byte size option to *fake* a zero length option and confuse the parsing logic, further achieve heap out-of-bounds read. One example crash log is like below: [ 3.905425] ================================================================== [ 3.905925] BUG: KASAN: slab-out-of-bounds in nla_put+0xa9/0xe0 [ 3.906255] Read of size 124 at addr ffff888005f291cc by task poc/177 [ 3.906646] [ 3.906775] CPU: 0 PID: 177 Comm: poc-oob-read Not tainted 6.1.132 #1 [ 3.907131] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014 [ 3.907784] Call Trace: [ 3.907925] <TASK> [ 3.908048] dump_stack_lvl+0x44/0x5c [ 3.908258] print_report+0x184/0x4be [ 3.909151] kasan_report+0xc5/0x100 [ 3.909539] kasan_check_range+0xf3/0x1a0 [ 3.909794] memcpy+0x1f/0x60 [ 3.909968] nla_put+0xa9/0xe0 [ 3.910147] tunnel_key_dump+0x945/0xba0 [ 3.911536] tcf_action_dump_1+0x1c1/0x340 [ 3.912436] tcf_action_dump+0x101/0x180 [ 3.912689] tcf_exts_dump+0x164/0x1e0 [ 3.912905] fw_dump+0x18b/0x2d0 [ 3.913483] tcf_fill_node+0x2ee/0x460 [ 3.914778] tfilter_notify+0xf4/0x180 [ 3.915208] tc_new_tfilter+0xd51/0x10d0 [ 3.918615] rtnetlink_rcv_msg+0x4a2/0x560 [ 3.919118] netlink_rcv_skb+0xcd/0x200 [ 3.919787] netlink_unicast+0x395/0x530 [ 3.921032] netlink_sendmsg+0x3d0/0x6d0 [ 3.921987] __sock_sendmsg+0x99/0xa0 [ 3.922220] __sys_sendto+0x1b7/0x240 [ 3.922682] __x64_sys_sendto+0x72/0x90 [ 3.922906] do_syscall_64+0x5e/0x90 [ 3.923814] entry_SYSCALL_64_after_hwframe+0x6e/0xd8 [ 3.924122] RIP: 0033:0x7e83eab84407 [ 3.924331] Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 faf [ 3.925330] RSP: 002b:00007ffff505e370 EFLAGS: 00000202 ORIG_RAX: 000000000000002c [ 3.925752] RAX: ffffffffffffffda RBX: 00007e83eaafa740 RCX: 00007e83eab84407 [ 3.926173] RDX: 00000000000001a8 RSI: 00007ffff505e3c0 RDI: 0000000000000003 [ 3.926587] RBP: 00007ffff505f460 R08: 00007e83eace1000 R09: 000000000000000c [ 3.926977] R10: 0000000000000000 R11: 0000000000000202 R12: 00007ffff505f3c0 [ 3.927367] R13: 00007ffff505f5c8 R14: 00007e83ead1b000 R15: 00005d4fbbe6dcb8 Fix these issues by enforing correct length condition in related policies. Fixes: 925d844696d9 ("netfilter: nft_tunnel: add support for geneve opts") Fixes: 4ece47787077 ("lwtunnel: add options setting and dumping for geneve") Fixes: 0ed5269f9e41 ("net/sched: add tunnel option support to act_tunnel_key") Fixes: 0a6e77784f49 ("net/sched: allow flower to match tunnel options") Signed-off-by: Lin Ma <linma@zju.edu.cn> Reviewed-by: Xin Long <lucien.xin@gmail.com> Acked-by: Cong Wang <xiyou.wangcong@gmail.com> Link: https://patch.msgid.link/20250402165632.6958-1-linma@zju.edu.cn Signed-off-by: Jakub Kicinski <kuba@kernel.org>