kernel/linux.git/include/linux/module.h, branch v6.6.131

module: add helper function for reading module_buildid()

2026-03-04T12:19:45+00:00

[ Upstream commit acfdbb4ab2910ff6f03becb569c23ac7b2223913 ] Add a helper function for reading the optional "build_id" member of struct module. It is going to be used also in ftrace_mod_address_lookup(). Use "#ifdef" instead of "#if IS_ENABLED()" to match the declaration of the optional field in struct module. Link: https://lkml.kernel.org/r/20251128135920.217303-4-pmladek@suse.com Signed-off-by: Petr Mladek Reviewed-by: Daniel Gomez Reviewed-by: Petr Pavlu Cc: Aaron Tomlin Cc: Alexei Starovoitov Cc: Daniel Borkman Cc: John Fastabend Cc: Kees Cook Cc: Luis Chamberalin Cc: Marc Rutland Cc: "Masami Hiramatsu (Google)" Cc: Sami Tolvanen Cc: Steven Rostedt (Google) Signed-off-by: Andrew Morton Stable-dep-of: e8a1e7eaa19d ("kallsyms/ftrace: set module buildid in ftrace_mod_address_lookup()") Signed-off-by: Sasha Levin

x86/its: Use dynamic thunks for indirect branches

2025-05-18T06:24:11+00:00

commit 872df34d7c51a79523820ea6a14860398c639b87 upstream. ITS mitigation moves the unsafe indirect branches to a safe thunk. This could degrade the prediction accuracy as the source address of indirect branches becomes same for different execution paths. To improve the predictions, and hence the performance, assign a separate thunk for each indirect callsite. This is also a defense-in-depth measure to avoid indirect branches aliasing with each other. As an example, 5000 dynamic thunks would utilize around 16 bits of the address space, thereby gaining entropy. For a BTB that uses 32 bits for indexing, dynamic thunks could provide better prediction accuracy over fixed thunks. Have ITS thunks be variable sized and use EXECMEM_MODULE_TEXT such that they are both more flexible (got to extend them later) and live in 2M TLBs, just like kernel code, avoiding undue TLB pressure. [ pawan: CONFIG_EXECMEM and CONFIG_EXECMEM_ROX are not supported on backport kernel, made changes to use module_alloc() and set_memory_*() for dynamic thunks. ] Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Pawan Gupta Signed-off-by: Dave Hansen Reviewed-by: Alexandre Chartre Signed-off-by: Greg Kroah-Hartman

kernel: globalize lookup_or_create_module_kobject()

2025-05-09T07:44:07+00:00

[ Upstream commit 7c76c813cfc42a7376378a0c4b7250db2eebab81 ] lookup_or_create_module_kobject() is marked as static and __init, to make it global drop static keyword. Since this function can be called from non-init code, use __modinit instead of __init, __modinit marker will make it __init if CONFIG_MODULES is not defined. Suggested-by: Rasmus Villemoes Signed-off-by: Shyam Saini Link: https://lore.kernel.org/r/20250227184930.34163-4-shyamsaini@linux.microsoft.com Signed-off-by: Petr Pavlu Stable-dep-of: f95bbfe18512 ("drivers: base: handle module_kobject creation") Signed-off-by: Sasha Levin

kallsyms: remove unsed API lookup_symbol_attrs

2023-05-26T22:10:18+00:00

with commit '7878c231dae0 ("slab: remove /proc/slab_allocators")' lookup_symbol_attrs usage is removed. Thus removing redundant API. Signed-off-by: Maninder Singh Reviewed-by: Kees Cook Signed-off-by: Luis Chamberlain

Merge tag 'modules-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux

2023-04-27T23:36:55+00:00

Pull module updates from Luis Chamberlain: "The summary of the changes for this pull requests is: - Song Liu's new struct module_memory replacement - Nick Alcock's MODULE_LICENSE() removal for non-modules - My cleanups and enhancements to reduce the areas where we vmalloc module memory for duplicates, and the respective debug code which proves the remaining vmalloc pressure comes from userspace. Most of the changes have been in linux-next for quite some time except the minor fixes I made to check if a module was already loaded prior to allocating the final module memory with vmalloc and the respective debug code it introduces to help clarify the issue. Although the functional change is small it is rather safe as it can only *help* reduce vmalloc space for duplicates and is confirmed to fix a bootup issue with over 400 CPUs with KASAN enabled. I don't expect stable kernels to pick up that fix as the cleanups would have also had to have been picked up. Folks on larger CPU systems with modules will want to just upgrade if vmalloc space has been an issue on bootup. Given the size of this request, here's some more elaborate details: The functional change change in this pull request is the very first patch from Song Liu which replaces the 'struct module_layout' with a new 'struct module_memory'. The old data structure tried to put together all types of supported module memory types in one data structure, the new one abstracts the differences in memory types in a module to allow each one to provide their own set of details. This paves the way in the future so we can deal with them in a cleaner way. If you look at changes they also provide a nice cleanup of how we handle these different memory areas in a module. This change has been in linux-next since before the merge window opened for v6.3 so to provide more than a full kernel cycle of testing. It's a good thing as quite a bit of fixes have been found for it. Jason Baron then made dynamic debug a first class citizen module user by using module notifier callbacks to allocate / remove module specific dynamic debug information. Nick Alcock has done quite a bit of work cross-tree to remove module license tags from things which cannot possibly be module at my request so to: a) help him with his longer term tooling goals which require a deterministic evaluation if a piece a symbol code could ever be part of a module or not. But quite recently it is has been made clear that tooling is not the only one that would benefit. Disambiguating symbols also helps efforts such as live patching, kprobes and BPF, but for other reasons and R&D on this area is active with no clear solution in sight. b) help us inch closer to the now generally accepted long term goal of automating all the MODULE_LICENSE() tags from SPDX license tags In so far as a) is concerned, although module license tags are a no-op for non-modules, tools which would want create a mapping of possible modules can only rely on the module license tag after the commit 8b41fc4454e ("kbuild: create modules.builtin without Makefile.modbuiltin or tristate.conf"). Nick has been working on this *for years* and AFAICT I was the only one to suggest two alternatives to this approach for tooling. The complexity in one of my suggested approaches lies in that we'd need a possible-obj-m and a could-be-module which would check if the object being built is part of any kconfig build which could ever lead to it being part of a module, and if so define a new define -DPOSSIBLE_MODULE [0]. A more obvious yet theoretical approach I've suggested would be to have a tristate in kconfig imply the same new -DPOSSIBLE_MODULE as well but that means getting kconfig symbol names mapping to modules always, and I don't think that's the case today. I am not aware of Nick or anyone exploring either of these options. Quite recently Josh Poimboeuf has pointed out that live patching, kprobes and BPF would benefit from resolving some part of the disambiguation as well but for other reasons. The function granularity KASLR (fgkaslr) patches were mentioned but Joe Lawrence has clarified this effort has been dropped with no clear solution in sight [1]. In the meantime removing module license tags from code which could never be modules is welcomed for both objectives mentioned above. Some developers have also welcomed these changes as it has helped clarify when a module was never possible and they forgot to clean this up, and so you'll see quite a bit of Nick's patches in other pull requests for this merge window. I just picked up the stragglers after rc3. LWN has good coverage on the motivation behind this work [2] and the typical cross-tree issues he ran into along the way. The only concrete blocker issue he ran into was that we should not remove the MODULE_LICENSE() tags from files which have no SPDX tags yet, even if they can never be modules. Nick ended up giving up on his efforts due to having to do this vetting and backlash he ran into from folks who really did *not understand* the core of the issue nor were providing any alternative / guidance. I've gone through his changes and dropped the patches which dropped the module license tags where an SPDX license tag was missing, it only consisted of 11 drivers. To see if a pull request deals with a file which lacks SPDX tags you can just use: ./scripts/spdxcheck.py -f \ $(git diff --name-only commid-id | xargs echo) You'll see a core module file in this pull request for the above, but that's not related to his changes. WE just need to add the SPDX license tag for the kernel/module/kmod.c file in the future but it demonstrates the effectiveness of the script. Most of Nick's changes were spread out through different trees, and I just picked up the slack after rc3 for the last kernel was out. Those changes have been in linux-next for over two weeks. The cleanups, debug code I added and final fix I added for modules were motivated by David Hildenbrand's report of boot failing on a systems with over 400 CPUs when KASAN was enabled due to running out of virtual memory space. Although the functional change only consists of 3 lines in the patch "module: avoid allocation if module is already present and ready", proving that this was the best we can do on the modules side took quite a bit of effort and new debug code. The initial cleanups I did on the modules side of things has been in linux-next since around rc3 of the last kernel, the actual final fix for and debug code however have only been in linux-next for about a week or so but I think it is worth getting that code in for this merge window as it does help fix / prove / evaluate the issues reported with larger number of CPUs. Userspace is not yet fixed as it is taking a bit of time for folks to understand the crux of the issue and find a proper resolution. Worst come to worst, I have a kludge-of-concept [3] of how to make kernel_read*() calls for modules unique / converge them, but I'm currently inclined to just see if userspace can fix this instead" Link: https://lore.kernel.org/all/Y/kXDqW+7d71C4wz@bombadil.infradead.org/ [0] Link: https://lkml.kernel.org/r/025f2151-ce7c-5630-9b90-98742c97ac65@redhat.com [1] Link: https://lwn.net/Articles/927569/ [2] Link: https://lkml.kernel.org/r/20230414052840.1994456-3-mcgrof@kernel.org [3] * tag 'modules-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux: (121 commits) module: add debugging auto-load duplicate module support module: stats: fix invalid_mod_bytes typo module: remove use of uninitialized variable len module: fix building stats for 32-bit targets module: stats: include uapi/linux/module.h module: avoid allocation if module is already present and ready module: add debug stats to help identify memory pressure module: extract patient module check into helper modules/kmod: replace implementation with a semaphore Change DEFINE_SEMAPHORE() to take a number argument module: fix kmemleak annotations for non init ELF sections module: Ignore L0 and rename is_arm_mapping_symbol() module: Move is_arm_mapping_symbol() to module_symbol.h module: Sync code of is_arm_mapping_symbol() scripts/gdb: use mem instead of core_layout to get the module address interconnect: remove module-related code interconnect: remove MODULE_LICENSE in non-modules zswap: remove MODULE_LICENSE in non-modules zpool: remove MODULE_LICENSE in non-modules x86/mm/dump_pagetables: remove MODULE_LICENSE in non-modules ...

Merge tag 'net-next-6.4' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next

2023-04-26T23:07:23+00:00

Pull networking updates from Paolo Abeni: "Core: - Introduce a config option to tweak MAX_SKB_FRAGS. Increasing the default value allows for better BIG TCP performances - Reduce compound page head access for zero-copy data transfers - RPS/RFS improvements, avoiding unneeded NET_RX_SOFTIRQ when possible - Threaded NAPI improvements, adding defer skb free support and unneeded softirq avoidance - Address dst_entry reference count scalability issues, via false sharing avoidance and optimize refcount tracking - Add lockless accesses annotation to sk_err[_soft] - Optimize again the skb struct layout - Extends the skb drop reasons to make it usable by multiple subsystems - Better const qualifier awareness for socket casts BPF: - Add skb and XDP typed dynptrs which allow BPF programs for more ergonomic and less brittle iteration through data and variable-sized accesses - Add a new BPF netfilter program type and minimal support to hook BPF programs to netfilter hooks such as prerouting or forward - Add more precise memory usage reporting for all BPF map types - Adds support for using {FOU,GUE} encap with an ipip device operating in collect_md mode and add a set of BPF kfuncs for controlling encap params - Allow BPF programs to detect at load time whether a particular kfunc exists or not, and also add support for this in light skeleton - Bigger batch of BPF verifier improvements to prepare for upcoming BPF open-coded iterators allowing for less restrictive looping capabilities - Rework RCU enforcement in the verifier, add kptr_rcu and enforce BPF programs to NULL-check before passing such pointers into kfunc - Add support for kptrs in percpu hashmaps, percpu LRU hashmaps and in local storage maps - Enable RCU semantics for task BPF kptrs and allow referenced kptr tasks to be stored in BPF maps - Add support for refcounted local kptrs to the verifier for allowing shared ownership, useful for adding a node to both the BPF list and rbtree - Add BPF verifier support for ST instructions in convert_ctx_access() which will help new -mcpu=v4 clang flag to start emitting them - Add ARM32 USDT support to libbpf - Improve bpftool's visual program dump which produces the control flow graph in a DOT format by adding C source inline annotations Protocols: - IPv4: Allow adding to IPv4 address a 'protocol' tag. Such value indicates the provenance of the IP address - IPv6: optimize route lookup, dropping unneeded R/W lock acquisition - Add the handshake upcall mechanism, allowing the user-space to implement generic TLS handshake on kernel's behalf - Bridge: support per-{Port, VLAN} neighbor suppression, increasing resilience to nodes failures - SCTP: add support for Fair Capacity and Weighted Fair Queueing schedulers - MPTCP: delay first subflow allocation up to its first usage. This will allow for later better LSM interaction - xfrm: Remove inner/outer modes from input/output path. These are not needed anymore - WiFi: - reduced neighbor report (RNR) handling for AP mode - HW timestamping support - support for randomized auth/deauth TA for PASN privacy - per-link debugfs for multi-link - TC offload support for mac80211 drivers - mac80211 mesh fast-xmit and fast-rx support - enable Wi-Fi 7 (EHT) mesh support Netfilter: - Add nf_tables 'brouting' support, to force a packet to be routed instead of being bridged - Update bridge netfilter and ovs conntrack helpers to handle IPv6 Jumbo packets properly, i.e. fetch the packet length from hop-by-hop extension header. This is needed for BIT TCP support - The iptables 32bit compat interface isn't compiled in by default anymore - Move ip(6)tables builtin icmp matches to the udptcp one. This has the advantage that icmp/icmpv6 match doesn't load the iptables/ip6tables modules anymore when iptables-nft is used - Extended netlink error report for netdevice in flowtables and netdev/chains. Allow for incrementally add/delete devices to netdev basechain. Allow to create netdev chain without device Driver API: - Remove redundant Device Control Error Reporting Enable, as PCI core has already error reporting enabled at enumeration time - Move Multicast DB netlink handlers to core, allowing devices other then bridge to use them - Allow the page_pool to directly recycle the pages from safely localized NAPI - Implement lockless TX queue stop/wake combo macros, allowing for further code de-duplication and sanitization - Add YNL support for user headers and struct attrs - Add partial YNL specification for devlink - Add partial YNL specification for ethtool - Add tc-mqprio and tc-taprio support for preemptible traffic classes - Add tx push buf len param to ethtool, specifies the maximum number of bytes of a transmitted packet a driver can push directly to the underlying device - Add basic LED support for switch/phy - Add NAPI documentation, stop relaying on external links - Convert dsa_master_ioctl() to netdev notifier. This is a preparatory work to make the hardware timestamping layer selectable by user space - Add transceiver support and improve the error messages for CAN-FD controllers New hardware / drivers: - Ethernet: - AMD/Pensando core device support - MediaTek MT7981 SoC - MediaTek MT7988 SoC - Broadcom BCM53134 embedded switch - Texas Instruments CPSW9G ethernet switch - Qualcomm EMAC3 DWMAC ethernet - StarFive JH7110 SoC - NXP CBTX ethernet PHY - WiFi: - Apple M1 Pro/Max devices - RealTek rtl8710bu/rtl8188gu - RealTek rtl8822bs, rtl8822cs and rtl8821cs SDIO chipset - Bluetooth: - Realtek RTL8821CS, RTL8851B, RTL8852BS - Mediatek MT7663, MT7922 - NXP w8997 - Actions Semi ATS2851 - QTI WCN6855 - Marvell 88W8997 - Can: - STMicroelectronics bxcan stm32f429 Drivers: - Ethernet NICs: - Intel (1G, icg): - add tracking and reporting of QBV config errors - add support for configuring max SDU for each Tx queue - Intel (100G, ice): - refactor mailbox overflow detection to support Scalable IOV - GNSS interface optimization - Intel (i40e): - support XDP multi-buffer - nVidia/Mellanox: - add the support for linux bridge multicast offload - enable TC offload for egress and engress MACVLAN over bond - add support for VxLAN GBP encap/decap flows offload - extend packet offload to fully support libreswan - support tunnel mode in mlx5 IPsec packet offload - extend XDP multi-buffer support - support MACsec VLAN offload - add support for dynamic msix vectors allocation - drop RX page_cache and fully use page_pool - implement thermal zone to report NIC temperature - Netronome/Corigine: - add support for multi-zone conntrack offload - Solarflare/Xilinx: - support offloading TC VLAN push/pop actions to the MAE - support TC decap rules - support unicast PTP - Other NICs: - Broadcom (bnxt): enforce software based freq adjustments only on shared PHC NIC - RealTek (r8169): refactor to addess ASPM issues during NAPI poll - Micrel (lan8841): add support for PTP_PF_PEROUT - Cadence (macb): enable PTP unicast - Engleder (tsnep): add XDP socket zero-copy support - virtio-net: implement exact header length guest feature - veth: add page_pool support for page recycling - vxlan: add MDB data path support - gve: add XDP support for GQI-QPL format - geneve: accept every ethertype - macvlan: allow some packets to bypass broadcast queue - mana: add support for jumbo frame - Ethernet high-speed switches: - Microchip (sparx5): Add support for TC flower templates - Ethernet embedded switches: - Broadcom (b54): - configure 6318 and 63268 RGMII ports - Marvell (mv88e6xxx): - faster C45 bus scan - Microchip: - lan966x: - add support for IS1 VCAP - better TX/RX from/to CPU performances - ksz9477: add ETS Qdisc support - ksz8: enhance static MAC table operations and error handling - sama7g5: add PTP capability - NXP (ocelot): - add support for external ports - add support for preemptible traffic classes - Texas Instruments: - add CPSWxG SGMII support for J7200 and J721E - Intel WiFi (iwlwifi): - preparation for Wi-Fi 7 EHT and multi-link support - EHT (Wi-Fi 7) sniffer support - hardware timestamping support for some devices/firwmares - TX beacon protection on newer hardware - Qualcomm 802.11ax WiFi (ath11k): - MU-MIMO parameters support - ack signal support for management packets - RealTek WiFi (rtw88): - SDIO bus support - better support for some SDIO devices (e.g. MAC address from efuse) - RealTek WiFi (rtw89): - HW scan support for 8852b - better support for 6 GHz scanning - support for various newer firmware APIs - framework firmware backwards compatibility - MediaTek WiFi (mt76): - P2P support - mesh A-MSDU support - EHT (Wi-Fi 7) support - coredump support" * tag 'net-next-6.4' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2078 commits) net: phy: hide the PHYLIB_LEDS knob net: phy: marvell-88x2222: remove unnecessary (void*) conversions tcp/udp: Fix memleaks of sk and zerocopy skbs with TX timestamp. net: amd: Fix link leak when verifying config failed net: phy: marvell: Fix inconsistent indenting in led_blink_set lan966x: Don't use xdp_frame when action is XDP_TX tsnep: Add XDP socket zero-copy TX support tsnep: Add XDP socket zero-copy RX support tsnep: Move skb receive action to separate function tsnep: Add functions for queue enable/disable tsnep: Rework TX/RX queue initialization tsnep: Replace modulo operation with mask net: phy: dp83867: Add led_brightness_set support net: phy: Fix reading LED reg property drivers: nfc: nfcsim: remove return value check of `dev_dir` net: phy: dp83867: Remove unnecessary (void*) conversions net: ethtool: coalesce: try to make user settings stick twice net: mana: Check if netdev/napi_alloc_frag returns single page net: mana: Rename mana_refill_rxoob and remove some empty lines net: veth: add page_pool stats ...

kallsyms: move module-related functions under correct configs

2023-04-06T04:31:11+00:00

Functions for searching module kallsyms should have non-empty definitions only if CONFIG_MODULES=y and CONFIG_KALLSYMS=y. Until now, only CONFIG_MODULES check was used for many of these, which may have caused complilation errors on some configs. This patch moves all relevant functions under the correct configs. Fixes: bd5314f8dd2d ("kallsyms, bpf: Move find_kallsyms_symbol_value out of internal header") Signed-off-by: Viktor Malik Reported-by: kernel test robot Link: https://lore.kernel.org/oe-kbuild-all/202303181535.RFDCnz3E-lkp@intel.com/ Link: https://lore.kernel.org/r/20230330102001.2183693-1-vmalik@redhat.com Signed-off-by: Alexei Starovoitov

kallsyms: Delete an unused parameter related to {module_}kallsyms_on_each_symbol()

2023-03-19T20:27:19+00:00

The parameter 'struct module *' in the hook function associated with {module_}kallsyms_on_each_symbol() is no longer used. Delete it. Suggested-by: Petr Mladek Signed-off-by: Zhen Lei Reviewed-by: Vincenzo Palazzo Acked-by: Jiri Olsa Acked-by: Steven Rostedt (Google) Signed-off-by: Luis Chamberlain

kallsyms, bpf: Move find_kallsyms_symbol_value out of internal header

2023-03-17T12:45:51+00:00

Moving find_kallsyms_symbol_value from kernel/module/internal.h to include/linux/module.h. The reason is that internal.h is not prepared to be included when CONFIG_MODULES=n. find_kallsyms_symbol_value is used by kernel/bpf/verifier.c and including internal.h from it (without modules) leads into a compilation error: In file included from ../include/linux/container_of.h:5, from ../include/linux/list.h:5, from ../include/linux/timer.h:5, from ../include/linux/workqueue.h:9, from ../include/linux/bpf.h:10, from ../include/linux/bpf-cgroup.h:5, from ../kernel/bpf/verifier.c:7: ../kernel/bpf/../module/internal.h: In function 'mod_find': ../include/linux/container_of.h:20:54: error: invalid use of undefined type 'struct module' 20 | static_assert(__same_type(*(ptr), ((type *)0)->member) || \ | ^~ [...] This patch fixes the above error. Fixes: 31bf1dbccfb0 ("bpf: Fix attaching fentry/fexit/fmod_ret/lsm to modules") Reported-by: kernel test robot Signed-off-by: Viktor Malik Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/oe-kbuild-all/202303161404.OrmfCy09-lkp@intel.com/ Link: https://lore.kernel.org/bpf/20230317095601.386738-1-vmalik@redhat.com

kernel/module: add documentation for try_module_get()

2023-03-10T18:55:59+00:00

There is quite a bit of tribal knowledge around proper use of try_module_get() and requiring *somehow* the module to still exist to use this call in a way that is safe. Document this bit of tribal knowledge. To be clear, you should only use try_module_get() *iff* you are 100% sure the module already does exist and is not on its way out. You can be sure the module still exists and is alive through: 1) Direct protection with its refcount: you know some earlier caller called __module_get() safely 2) Implied protection: there is an implied protection against module removal Having an idea of when you are sure __module_get() might be called earlier is easy to understand however the implied protection requires an example. We use sysfs an an example for implied protection without a direct module reference count bump. kernfs / sysfs uses its own internal reference counting for files being actively used, when such file are active they completely prevent the module from being removed. kernfs protects this with its kernfs_active(). Effort has been put into verifying the kernfs implied protection works by using a currently out-of-tree test_sysfs selftest test #32 [0]: ./tools/testing/selftests/sysfs/sysfs.sh -t 0032 Without kernfs / sysfs preventing module removal through its active reference count (kernfs_active()) the write would fail or worse, a crash would happen in this test and it does not. Similar safeguards are required for other users of try_module_get() *iff* they are not ensuring the above rule 1) is followed. [0] https://lore.kernel.org/lkml/20211029184500.2821444-4-mcgrof@kernel.org/ Signed-off-by: Luis Chamberlain