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2022-12-16Merge tag 'driver-core-6.2-rc1' of ↵Linus Torvalds1-10/+10
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core updates from Greg KH: "Here is the set of driver core and kernfs changes for 6.2-rc1. The "big" change in here is the addition of a new macro, container_of_const() that will preserve the "const-ness" of a pointer passed into it. The "problem" of the current container_of() macro is that if you pass in a "const *", out of it can comes a non-const pointer unless you specifically ask for it. For many usages, we want to preserve the "const" attribute by using the same call. For a specific example, this series changes the kobj_to_dev() macro to use it, allowing it to be used no matter what the const value is. This prevents every subsystem from having to declare 2 different individual macros (i.e. kobj_const_to_dev() and kobj_to_dev()) and having the compiler enforce the const value at build time, which having 2 macros would not do either. The driver for all of this have been discussions with the Rust kernel developers as to how to properly mark driver core, and kobject, objects as being "non-mutable". The changes to the kobject and driver core in this pull request are the result of that, as there are lots of paths where kobjects and device pointers are not modified at all, so marking them as "const" allows the compiler to enforce this. So, a nice side affect of the Rust development effort has been already to clean up the driver core code to be more obvious about object rules. All of this has been bike-shedded in quite a lot of detail on lkml with different names and implementations resulting in the tiny version we have in here, much better than my original proposal. Lots of subsystem maintainers have acked the changes as well. Other than this change, included in here are smaller stuff like: - kernfs fixes and updates to handle lock contention better - vmlinux.lds.h fixes and updates - sysfs and debugfs documentation updates - device property updates All of these have been in the linux-next tree for quite a while with no problems" * tag 'driver-core-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (58 commits) device property: Fix documentation for fwnode_get_next_parent() firmware_loader: fix up to_fw_sysfs() to preserve const usb.h: take advantage of container_of_const() device.h: move kobj_to_dev() to use container_of_const() container_of: add container_of_const() that preserves const-ness of the pointer driver core: fix up missed drivers/s390/char/hmcdrv_dev.c class.devnode() conversion. driver core: fix up missed scsi/cxlflash class.devnode() conversion. driver core: fix up some missing class.devnode() conversions. driver core: make struct class.devnode() take a const * driver core: make struct class.dev_uevent() take a const * cacheinfo: Remove of_node_put() for fw_token device property: Add a blank line in Kconfig of tests device property: Rename goto label to be more precise device property: Move PROPERTY_ENTRY_BOOL() a bit down device property: Get rid of __PROPERTY_ENTRY_ARRAY_EL*SIZE*() kernfs: fix all kernel-doc warnings and multiple typos driver core: pass a const * into of_device_uevent() kobject: kset_uevent_ops: make name() callback take a const * kobject: kset_uevent_ops: make filter() callback take a const * kobject: make kobject_namespace take a const * ...
2022-11-24driver core: make struct class.dev_uevent() take a const *Greg Kroah-Hartman1-2/+2
The dev_uevent() in struct class should not be modifying the device that is passed into it, so mark it as a const * and propagate the function signature changes out into all relevant subsystems that use this callback. Cc: Jens Axboe <axboe@kernel.dk> Cc: Luis Chamberlain <mcgrof@kernel.org> Cc: Russ Weight <russell.h.weight@intel.com> Cc: Jean Delvare <jdelvare@suse.com> Cc: Johan Hovold <johan@kernel.org> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Leon Romanovsky <leon@kernel.org> Cc: Karsten Keil <isdn@linux-pingi.de> Cc: Mauro Carvalho Chehab <mchehab@kernel.org> Cc: Keith Busch <kbusch@kernel.org> Cc: Christoph Hellwig <hch@lst.de> Cc: Sagi Grimberg <sagi@grimberg.me> Cc: Dominik Brodowski <linux@dominikbrodowski.net> Cc: "David S. Miller" <davem@davemloft.net> Cc: Eric Dumazet <edumazet@google.com> Cc: Jakub Kicinski <kuba@kernel.org> Cc: Paolo Abeni <pabeni@redhat.com> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Wolfram Sang <wsa+renesas@sang-engineering.com> Cc: Raed Salem <raeds@nvidia.com> Cc: Chen Zhongjin <chenzhongjin@huawei.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Avihai Horon <avihaih@nvidia.com> Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org> Cc: Alan Stern <stern@rowland.harvard.edu> Cc: Colin Ian King <colin.i.king@gmail.com> Cc: Geert Uytterhoeven <geert+renesas@glider.be> Cc: Jakob Koschel <jakobkoschel@gmail.com> Cc: Antoine Tenart <atenart@kernel.org> Cc: Frederic Weisbecker <frederic@kernel.org> Cc: Wang Yufen <wangyufen@huawei.com> Cc: linux-block@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: linux-media@vger.kernel.org Cc: linux-nvme@lists.infradead.org Cc: linux-pm@vger.kernel.org Cc: linux-rdma@vger.kernel.org Cc: linux-usb@vger.kernel.org Cc: linux-wireless@vger.kernel.org Cc: netdev@vger.kernel.org Acked-by: Sebastian Reichel <sre@kernel.org> Acked-by: Rafael J. Wysocki <rafael@kernel.org> Link: https://lore.kernel.org/r/20221123122523.1332370-1-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-22kobject: make kobject_get_ownership() take a constant kobject *Greg Kroah-Hartman1-4/+4
The call, kobject_get_ownership(), does not modify the kobject passed into it, so make it const. This propagates down into the kobj_type function callbacks so make the kobject passed into them also const, ensuring that nothing in the kobject is being changed here. This helps make it more obvious what calls and callbacks do, and do not, modify structures passed to them. Cc: Trond Myklebust <trond.myklebust@hammerspace.com> Cc: Anna Schumaker <anna@kernel.org> Cc: Roopa Prabhu <roopa@nvidia.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Eric Dumazet <edumazet@google.com> Cc: Paolo Abeni <pabeni@redhat.com> Cc: Chuck Lever <chuck.lever@oracle.com> Cc: Jeff Layton <jlayton@kernel.org> Cc: linux-nfs@vger.kernel.org Cc: bridge@lists.linux-foundation.org Cc: netdev@vger.kernel.org Acked-by: Jakub Kicinski <kuba@kernel.org> Acked-by: Rafael J. Wysocki <rafael@kernel.org> Acked-by: Nikolay Aleksandrov <razor@blackwall.org> Link: https://lore.kernel.org/r/20221121094649.1556002-1-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-09driver core: class: make namespace and get_ownership take const *Greg Kroah-Hartman1-4/+4
The callbacks in struct class namespace() and get_ownership() do not modify the struct device passed to them, so mark the pointer as constant and fix up all callbacks in the kernel to have the correct function signature. This helps make it more obvious what calls and callbacks do, and do not, modify structures passed to them. Cc: "Rafael J. Wysocki" <rafael@kernel.org> Link: https://lore.kernel.org/r/20221001165426.2690912-1-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-03net: devlink: use devlink_port pointer instead of ndo_get_devlink_portJiri Pirko1-2/+2
Use newly introduced devlink_port pointer instead of getting it calling to ndo_get_devlink_port op. Signed-off-by: Jiri Pirko <jiri@nvidia.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-09-30net-sysfs: Convert to use sysfs_emit() APIsWang Yufen1-29/+29
Follow the advice of the Documentation/filesystems/sysfs.rst and show() should only use sysfs_emit() or sysfs_emit_at() when formatting the value to be returned to user space. Signed-off-by: Wang Yufen <wangyufen@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-06-23Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski1-0/+1
No conflicts. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-06-17net: fix data-race in dev_isalive()Eric Dumazet1-0/+1
dev_isalive() is called under RTNL or dev_base_lock protection. This means that changes to dev->reg_state should be done with both locks held. syzbot reported: BUG: KCSAN: data-race in register_netdevice / type_show write to 0xffff888144ecf518 of 1 bytes by task 20886 on cpu 0: register_netdevice+0xb9f/0xdf0 net/core/dev.c:10050 lapbeth_new_device drivers/net/wan/lapbether.c:414 [inline] lapbeth_device_event+0x4a0/0x6c0 drivers/net/wan/lapbether.c:456 notifier_call_chain kernel/notifier.c:87 [inline] raw_notifier_call_chain+0x53/0xb0 kernel/notifier.c:455 __dev_notify_flags+0x1d6/0x3a0 dev_change_flags+0xa2/0xc0 net/core/dev.c:8607 do_setlink+0x778/0x2230 net/core/rtnetlink.c:2780 __rtnl_newlink net/core/rtnetlink.c:3546 [inline] rtnl_newlink+0x114c/0x16a0 net/core/rtnetlink.c:3593 rtnetlink_rcv_msg+0x811/0x8c0 net/core/rtnetlink.c:6089 netlink_rcv_skb+0x13e/0x240 net/netlink/af_netlink.c:2501 rtnetlink_rcv+0x18/0x20 net/core/rtnetlink.c:6107 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0x58a/0x660 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x661/0x750 net/netlink/af_netlink.c:1921 sock_sendmsg_nosec net/socket.c:714 [inline] sock_sendmsg net/socket.c:734 [inline] __sys_sendto+0x21e/0x2c0 net/socket.c:2119 __do_sys_sendto net/socket.c:2131 [inline] __se_sys_sendto net/socket.c:2127 [inline] __x64_sys_sendto+0x74/0x90 net/socket.c:2127 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x46/0xb0 read to 0xffff888144ecf518 of 1 bytes by task 20423 on cpu 1: dev_isalive net/core/net-sysfs.c:38 [inline] netdev_show net/core/net-sysfs.c:50 [inline] type_show+0x24/0x90 net/core/net-sysfs.c:112 dev_attr_show+0x35/0x90 drivers/base/core.c:2095 sysfs_kf_seq_show+0x175/0x240 fs/sysfs/file.c:59 kernfs_seq_show+0x75/0x80 fs/kernfs/file.c:162 seq_read_iter+0x2c3/0x8e0 fs/seq_file.c:230 kernfs_fop_read_iter+0xd1/0x2f0 fs/kernfs/file.c:235 call_read_iter include/linux/fs.h:2052 [inline] new_sync_read fs/read_write.c:401 [inline] vfs_read+0x5a5/0x6a0 fs/read_write.c:482 ksys_read+0xe8/0x1a0 fs/read_write.c:620 __do_sys_read fs/read_write.c:630 [inline] __se_sys_read fs/read_write.c:628 [inline] __x64_sys_read+0x3e/0x50 fs/read_write.c:628 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x46/0xb0 value changed: 0x00 -> 0x01 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 20423 Comm: udevd Tainted: G W 5.19.0-rc2-syzkaller-dirty #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-06-09net: rename reference+tracking helpersJakub Kicinski1-4/+4
Netdev reference helpers have a dev_ prefix for historic reasons. Renaming the old helpers would be too much churn but we can rename the tracking ones which are relatively recent and should be the default for new code. Rename: dev_hold_track() -> netdev_hold() dev_put_track() -> netdev_put() dev_replace_track() -> netdev_ref_replace() Link: https://lore.kernel.org/r/20220608043955.919359-1-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-05-22net: wrap the wireless pointers in struct net_device in an ifdefJakub Kicinski1-8/+13
Most protocol-specific pointers in struct net_device are under a respective ifdef. Wireless is the notable exception. Since there's a sizable number of custom-built kernels for datacenter workloads which don't build wireless it seems reasonable to ifdefy those pointers as well. While at it move IPv4 and IPv6 pointers up, those are special for obvious reasons. Acked-by: Johannes Berg <johannes@sipsolutions.net> Acked-by: Stefan Schmidt <stefan@datenfreihafen.org> # ieee802154 Acked-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-07net: extract a few internals from netdevice.hJakub Kicinski1-0/+1
There's a number of functions and static variables used under net/core/ but not from the outside. We currently dump most of them into netdevice.h. That bad for many reasons: - netdevice.h is very cluttered, hard to figure out what the APIs are; - netdevice.h is very long; - we have to touch netdevice.h more which causes expensive incremental builds. Create a header under net/core/ and move some declarations. The new header is also a bit of a catch-all but that's fine, if we create more specific headers people will likely over-think where their declaration fit best. And end up putting them in netdevice.h, again. More work should be done on splitting netdevice.h into more targeted headers, but that'd be more time consuming so small steps. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-03-15Merge tag 'v5.17-rc8' into sched/core, to pick up fixesIngo Molnar1-1/+1
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2022-02-18net-sysfs: add check for netdevice being present to speed_showsuresh kumar1-1/+1
When bringing down the netdevice or system shutdown, a panic can be triggered while accessing the sysfs path because the device is already removed. [ 755.549084] mlx5_core 0000:12:00.1: Shutdown was called [ 756.404455] mlx5_core 0000:12:00.0: Shutdown was called ... [ 757.937260] BUG: unable to handle kernel NULL pointer dereference at (null) [ 758.031397] IP: [<ffffffff8ee11acb>] dma_pool_alloc+0x1ab/0x280 crash> bt ... PID: 12649 TASK: ffff8924108f2100 CPU: 1 COMMAND: "amsd" ... #9 [ffff89240e1a38b0] page_fault at ffffffff8f38c778 [exception RIP: dma_pool_alloc+0x1ab] RIP: ffffffff8ee11acb RSP: ffff89240e1a3968 RFLAGS: 00010046 RAX: 0000000000000246 RBX: ffff89243d874100 RCX: 0000000000001000 RDX: 0000000000000000 RSI: 0000000000000246 RDI: ffff89243d874090 RBP: ffff89240e1a39c0 R8: 000000000001f080 R9: ffff8905ffc03c00 R10: ffffffffc04680d4 R11: ffffffff8edde9fd R12: 00000000000080d0 R13: ffff89243d874090 R14: ffff89243d874080 R15: 0000000000000000 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 #10 [ffff89240e1a39c8] mlx5_alloc_cmd_msg at ffffffffc04680f3 [mlx5_core] #11 [ffff89240e1a3a18] cmd_exec at ffffffffc046ad62 [mlx5_core] #12 [ffff89240e1a3ab8] mlx5_cmd_exec at ffffffffc046b4fb [mlx5_core] #13 [ffff89240e1a3ae8] mlx5_core_access_reg at ffffffffc0475434 [mlx5_core] #14 [ffff89240e1a3b40] mlx5e_get_fec_caps at ffffffffc04a7348 [mlx5_core] #15 [ffff89240e1a3bb0] get_fec_supported_advertised at ffffffffc04992bf [mlx5_core] #16 [ffff89240e1a3c08] mlx5e_get_link_ksettings at ffffffffc049ab36 [mlx5_core] #17 [ffff89240e1a3ce8] __ethtool_get_link_ksettings at ffffffff8f25db46 #18 [ffff89240e1a3d48] speed_show at ffffffff8f277208 #19 [ffff89240e1a3dd8] dev_attr_show at ffffffff8f0b70e3 #20 [ffff89240e1a3df8] sysfs_kf_seq_show at ffffffff8eedbedf #21 [ffff89240e1a3e18] kernfs_seq_show at ffffffff8eeda596 #22 [ffff89240e1a3e28] seq_read at ffffffff8ee76d10 #23 [ffff89240e1a3e98] kernfs_fop_read at ffffffff8eedaef5 #24 [ffff89240e1a3ed8] vfs_read at ffffffff8ee4e3ff #25 [ffff89240e1a3f08] sys_read at ffffffff8ee4f27f #26 [ffff89240e1a3f50] system_call_fastpath at ffffffff8f395f92 crash> net_device.state ffff89443b0c0000 state = 0x5 (__LINK_STATE_START| __LINK_STATE_NOCARRIER) To prevent this scenario, we also make sure that the netdevice is present. Signed-off-by: suresh kumar <suresh2514@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-16sched/isolation: Use single feature type while referring to housekeeping cpumaskFrederic Weisbecker1-2/+2
Refer to housekeeping APIs using single feature types instead of flags. This prevents from passing multiple isolation features at once to housekeeping interfaces, which soon won't be possible anymore as each isolation features will have their own cpumask. Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Juri Lelli <juri.lelli@redhat.com> Reviewed-by: Phil Auld <pauld@redhat.com> Link: https://lore.kernel.org/r/20220207155910.527133-5-frederic@kernel.org
2022-02-16net: Decouple HK_FLAG_WQ and HK_FLAG_DOMAIN cpumask fetchFrederic Weisbecker1-3/+3
To prepare for supporting each feature of the housekeeping cpumask toward cpuset, prepare each of the HK_FLAG_* entries to move to their own cpumask with enforcing to fetch them individually. The new constraint is that multiple HK_FLAG_* entries can't be mixed together anymore in a single call to housekeeping cpumask(). This will later allow, for example, to runtime modify the cpulist passed through "isolcpus=", "nohz_full=" and "rcu_nocbs=" kernel boot parameters. Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Juri Lelli <juri.lelli@redhat.com> Reviewed-by: Phil Auld <pauld@redhat.com> Link: https://lore.kernel.org/r/20220207155910.527133-4-frederic@kernel.org
2021-12-08net-sysfs: warn if new queue objects are being created during device ↵Antoine Tenart1-0/+7
unregistration Calling netdev_queue_update_kobjects is allowed during device unregistration since commit 5c56580b74e5 ("net: Adjust TX queue kobjects if number of queues changes during unregister"). But this is solely to allow queue unregistrations. Any path attempting to add new queues after a device started its unregistration should be fixed. This patch adds a warning to detect such illegal use. Signed-off-by: Antoine Tenart <atenart@kernel.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-08net-sysfs: update the queue counts in the unregistration pathAntoine Tenart1-0/+3
When updating Rx and Tx queue kobjects, the queue count should always be updated to match the queue kobjects count. This was not done in the net device unregistration path, fix it. Tracking all queue count updates will allow in a following up patch to detect illegal updates. Signed-off-by: Antoine Tenart <atenart@kernel.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-06net: add net device refcount tracker to struct netdev_queueEric Dumazet1-2/+2
This will help debugging pesky netdev reference leaks. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-06net: add net device refcount tracker to struct netdev_rx_queueEric Dumazet1-2/+2
This helps debugging net device refcount leaks. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-23net: remove .ndo_change_proto_downJakub Kicinski1-8/+0
.ndo_change_proto_down was added seemingly to enable out-of-tree implementations. Over 2.5yrs later we still have no real users upstream. Hardwire the generic implementation for now, we can revert once real users materialize. (rocker is a test vehicle, not a user.) We need to drop the optimization on the sysfs side, because unlike ndos priv_flags will be changed at runtime, so we'd need READ_ONCE/WRITE_ONCE everywhere.. Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-22net-sysfs: Slightly optimize 'xps_queue_show()'Christophe JAILLET1-1/+1
The 'mask' bitmap is local to this function. So the non-atomic '__set_bit()' can be used to save a few cycles. Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-17net: use an atomic_long_t for queue->trans_timeoutEric Dumazet1-5/+1
tx_timeout_show() assumed dev_watchdog() would stop all the queues, to fetch queue->trans_timeout under protection of the queue->_xmit_lock. As we want to no longer disrupt transmits, we use an atomic_long_t instead. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: david decotigny <david.decotigny@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-28Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski1-2/+2
include/net/sock.h 7b50ecfcc6cd ("net: Rename ->stream_memory_read to ->sock_is_readable") 4c1e34c0dbff ("vsock: Enable y2038 safe timeval for timeout") drivers/net/ethernet/marvell/octeontx2/af/rvu_debugfs.c 0daa55d033b0 ("octeontx2-af: cn10k: debugfs for dumping LMTST map table") e77bcdd1f639 ("octeontx2-af: Display all enabled PF VF rsrc_alloc entries.") Adjacent code addition in both cases, keep both. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-25net-sysfs: initialize uid and gid before calling net_ns_get_ownershipXin Long1-2/+2
Currently in net_ns_get_ownership() it may not be able to set uid or gid if make_kuid or make_kgid returns an invalid value, and an uninit-value issue can be triggered by this. This patch is to fix it by initializing the uid and gid before calling net_ns_get_ownership(), as it does in kobject_get_ownership() Fixes: e6dee9f3893c ("net-sysfs: add netdev_change_owner()") Reported-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: Christian Brauner <christian.brauner@ubuntu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-08net-sysfs: try not to restart the syscall if it will fail eventuallyAntoine Tenart1-0/+55
Due to deadlocks in the networking subsystem spotted 12 years ago[1], a workaround was put in place[2] to avoid taking the rtnl lock when it was not available and restarting the syscall (back to VFS, letting userspace spin). The following construction is found a lot in the net sysfs and sysctl code: if (!rtnl_trylock()) return restart_syscall(); This can be problematic when multiple userspace threads use such interfaces in a short period, making them to spin a lot. This happens for example when adding and moving virtual interfaces: userspace programs listening on events, such as systemd-udevd and NetworkManager, do trigger actions reading files in sysfs. It gets worse when a lot of virtual interfaces are created concurrently, say when creating containers at boot time. Returning early without hitting the above pattern when the syscall will fail eventually does make things better. While it is not a fix for the issue, it does ease things. [1] https://lore.kernel.org/netdev/49A4D5D5.5090602@trash.net/ https://lore.kernel.org/netdev/m14oyhis31.fsf@fess.ebiederm.org/ and https://lore.kernel.org/netdev/20090226084924.16cb3e08@nehalam/ [2] Rightfully, those deadlocks are *hard* to solve. Signed-off-by: Antoine Tenart <atenart@kernel.org> Reviewed-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-07of: net: move of_net under net/Jakub Kicinski1-1/+1
Rob suggests to move of_net.c from under drivers/of/ somewhere to the networking code. Suggested-by: Rob Herring <robh@kernel.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: Rob Herring <robh@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-22net-sysfs: remove possible sleep from an RCU read-side critical sectionAntoine Tenart1-1/+1
xps_queue_show is mostly made of an RCU read-side critical section and calls bitmap_zalloc with GFP_KERNEL in the middle of it. That is not allowed as this call may sleep and such behaviours aren't allowed in RCU read-side critical sections. Fix this by using GFP_NOWAIT instead. Fixes: 5478fcd0f483 ("net: embed nr_ids in the xps maps") Reported-by: kernel test robot <oliver.sang@intel.com> Suggested-by: Matthew Wilcox <willy@infradead.org> Signed-off-by: Antoine Tenart <atenart@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-18net-sysfs: move the xps cpus/rxqs retrieval in a common functionAntoine Tenart1-77/+48
Most of the xps_cpus_show and xps_rxqs_show functions share the same logic. Having it in two different functions does not help maintenance. This patch moves their common logic into a new function, xps_queue_show, to improve this. Signed-off-by: Antoine Tenart <atenart@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-18net-sysfs: move the rtnl unlock up in the xps show helpersAntoine Tenart1-14/+11
Now that nr_ids and num_tc are stored in the xps dev_maps, which are RCU protected, we do not have the need to protect the maps in the rtnl lock. Move the rtnl unlock up so we reduce the rtnl locking section. We also increase the reference count on the subordinate device if any, as we don't want this device to be freed while we use it (now that the rtnl lock isn't protecting it in the whole function). Signed-off-by: Antoine Tenart <atenart@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-18net: move the xps maps to an arrayAntoine Tenart1-3/+3
Move the xps maps (xps_cpus_map and xps_rxqs_map) to an array in net_device. That will simplify a lot the code removing the need for lots of if/else conditionals as the correct map will be available using its offset in the array. This should not modify the xps maps behaviour in any way. Suggested-by: Alexander Duyck <alexander.duyck@gmail.com> Signed-off-by: Antoine Tenart <atenart@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-18net: remove the xps possible_maskAntoine Tenart1-2/+2
Remove the xps possible_mask. It was an optimization but we can just loop from 0 to nr_ids now that it is embedded in the xps dev_maps. That simplifies the code a bit. Suggested-by: Alexander Duyck <alexander.duyck@gmail.com> Signed-off-by: Antoine Tenart <atenart@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-18net: embed nr_ids in the xps mapsAntoine Tenart1-16/+22
Embed nr_ids (the number of cpu for the xps cpus map, and the number of rxqs for the xps cpus map) in dev_maps. That will help not accessing out of bound memory if those values change after dev_maps was allocated. Suggested-by: Alexander Duyck <alexander.duyck@gmail.com> Signed-off-by: Antoine Tenart <atenart@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-18net: embed num_tc in the xps mapsAntoine Tenart1-28/+17
The xps cpus/rxqs map is accessed using dev->num_tc, which is used when allocating the map. But later updates of dev->num_tc can lead to having a mismatch between the maps and how they're accessed. In such cases the map values do not make any sense and out of bound accesses can occur (that can be easily seen using KASAN). This patch aims at fixing this by embedding num_tc into the maps, using the value at the time the map is created. This brings two improvements: - The maps can be accessed using the embedded num_tc, so we know for sure we won't have out of bound accesses. - Checks can be made before accessing the maps so we know the values retrieved will make sense. We also update __netif_set_xps_queue to conditionally copy old maps from dev_maps in the new one only if the number of traffic classes from both maps match. Signed-off-by: Antoine Tenart <atenart@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-18net-sysfs: make xps_cpus_show and xps_rxqs_show consistentAntoine Tenart1-15/+18
Make the implementations of xps_cpus_show and xps_rxqs_show to converge, as the two share the same logic but diverted over time. This should not modify their behaviour but will help future changes and improve maintenance. Signed-off-by: Antoine Tenart <atenart@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-18net-sysfs: store the return of get_netdev_queue_index in an unsigned intAntoine Tenart1-4/+7
In net-sysfs, get_netdev_queue_index returns an unsigned int. Some of its callers use an unsigned long to store the returned value. Update the code to be consistent, this should only be cosmetic. Signed-off-by: Antoine Tenart <atenart@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-18net-sysfs: convert xps_cpus_show to bitmap_zallocAntoine Tenart1-6/+6
Use bitmap_zalloc instead of zalloc_cpumask_var in xps_cpus_show to align with xps_rxqs_show. This will improve maintenance and allow us to factorize the two functions. The function should behave the same. Signed-off-by: Antoine Tenart <atenart@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-02-09net: add sysfs attribute to control napi threaded modeWei Wang1-0/+40
This patch adds a new sysfs attribute to the network device class. Said attribute provides a per-device control to enable/disable the threaded mode for all the napi instances of the given network device, without the need for a device up/down. User sets it to 1 or 0 to enable or disable threaded mode. Note: when switching between threaded and the current softirq based mode for a napi instance, it will not immediately take effect if the napi is currently being polled. The mode switch will happen for the next time napi_schedule() is called. Co-developed-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Co-developed-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Co-developed-by: Felix Fietkau <nbd@nbd.name> Signed-off-by: Felix Fietkau <nbd@nbd.name> Signed-off-by: Wei Wang <weiwan@google.com> Reviewed-by: Alexander Duyck <alexanderduyck@fb.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-02-08net-sysfs: Add rtnl locking for getting Tx queue traffic classAlexander Duyck1-3/+10
In order to access the suboordinate dev for a device we should be holding the rtnl_lock when outside of the transmit path. The existing code was not doing that for the sysfs dump function and as a result we were open to a possible race. To resolve that take the rtnl lock prior to accessing the sb_dev field of the Tx queue and release it after we have retrieved the tc for the queue. Signed-off-by: Alexander Duyck <alexanderduyck@fb.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-12-28net-sysfs: take the rtnl lock when accessing xps_rxqs_map and num_tcAntoine Tenart1-5/+18
Accesses to dev->xps_rxqs_map (when using dev->num_tc) should be protected by the rtnl lock, like we do for netif_set_xps_queue. I didn't see an actual bug being triggered, but let's be safe here and take the rtnl lock while accessing the map in sysfs. Fixes: 8af2c06ff4b1 ("net-sysfs: Add interface for Rx queue(s) map per Tx queue") Signed-off-by: Antoine Tenart <atenart@kernel.org> Reviewed-by: Alexander Duyck <alexanderduyck@fb.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-12-28net-sysfs: take the rtnl lock when storing xps_rxqsAntoine Tenart1-0/+7
Two race conditions can be triggered when storing xps rxqs, resulting in various oops and invalid memory accesses: 1. Calling netdev_set_num_tc while netif_set_xps_queue: - netif_set_xps_queue uses dev->tc_num as one of the parameters to compute the size of new_dev_maps when allocating it. dev->tc_num is also used to access the map, and the compiler may generate code to retrieve this field multiple times in the function. - netdev_set_num_tc sets dev->tc_num. If new_dev_maps is allocated using dev->tc_num and then dev->tc_num is set to a higher value through netdev_set_num_tc, later accesses to new_dev_maps in netif_set_xps_queue could lead to accessing memory outside of new_dev_maps; triggering an oops. 2. Calling netif_set_xps_queue while netdev_set_num_tc is running: 2.1. netdev_set_num_tc starts by resetting the xps queues, dev->tc_num isn't updated yet. 2.2. netif_set_xps_queue is called, setting up the map with the *old* dev->num_tc. 2.3. netdev_set_num_tc updates dev->tc_num. 2.4. Later accesses to the map lead to out of bound accesses and oops. A similar issue can be found with netdev_reset_tc. One way of triggering this is to set an iface up (for which the driver uses netdev_set_num_tc in the open path, such as bnx2x) and writing to xps_rxqs in a concurrent thread. With the right timing an oops is triggered. Both issues have the same fix: netif_set_xps_queue, netdev_set_num_tc and netdev_reset_tc should be mutually exclusive. We do that by taking the rtnl lock in xps_rxqs_store. Fixes: 8af2c06ff4b1 ("net-sysfs: Add interface for Rx queue(s) map per Tx queue") Signed-off-by: Antoine Tenart <atenart@kernel.org> Reviewed-by: Alexander Duyck <alexanderduyck@fb.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-12-28net-sysfs: take the rtnl lock when accessing xps_cpus_map and num_tcAntoine Tenart1-7/+22
Accesses to dev->xps_cpus_map (when using dev->num_tc) should be protected by the rtnl lock, like we do for netif_set_xps_queue. I didn't see an actual bug being triggered, but let's be safe here and take the rtnl lock while accessing the map in sysfs. Fixes: 184c449f91fe ("net: Add support for XPS with QoS via traffic classes") Signed-off-by: Antoine Tenart <atenart@kernel.org> Reviewed-by: Alexander Duyck <alexanderduyck@fb.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-12-28net-sysfs: take the rtnl lock when storing xps_cpusAntoine Tenart1-0/+6
Two race conditions can be triggered when storing xps cpus, resulting in various oops and invalid memory accesses: 1. Calling netdev_set_num_tc while netif_set_xps_queue: - netif_set_xps_queue uses dev->tc_num as one of the parameters to compute the size of new_dev_maps when allocating it. dev->tc_num is also used to access the map, and the compiler may generate code to retrieve this field multiple times in the function. - netdev_set_num_tc sets dev->tc_num. If new_dev_maps is allocated using dev->tc_num and then dev->tc_num is set to a higher value through netdev_set_num_tc, later accesses to new_dev_maps in netif_set_xps_queue could lead to accessing memory outside of new_dev_maps; triggering an oops. 2. Calling netif_set_xps_queue while netdev_set_num_tc is running: 2.1. netdev_set_num_tc starts by resetting the xps queues, dev->tc_num isn't updated yet. 2.2. netif_set_xps_queue is called, setting up the map with the *old* dev->num_tc. 2.3. netdev_set_num_tc updates dev->tc_num. 2.4. Later accesses to the map lead to out of bound accesses and oops. A similar issue can be found with netdev_reset_tc. One way of triggering this is to set an iface up (for which the driver uses netdev_set_num_tc in the open path, such as bnx2x) and writing to xps_cpus in a concurrent thread. With the right timing an oops is triggered. Both issues have the same fix: netif_set_xps_queue, netdev_set_num_tc and netdev_reset_tc should be mutually exclusive. We do that by taking the rtnl lock in xps_cpus_store. Fixes: 184c449f91fe ("net: Add support for XPS with QoS via traffic classes") Signed-off-by: Antoine Tenart <atenart@kernel.org> Reviewed-by: Alexander Duyck <alexanderduyck@fb.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-12-14Merge tag 'fixes-v5.11' of ↵Linus Torvalds1-3/+3
git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux Pull misc fixes from Christian Brauner: "This contains several fixes which felt worth being combined into a single branch: - Use put_nsproxy() instead of open-coding it switch_task_namespaces() - Kirill's work to unify lifecycle management for all namespaces. The lifetime counters are used identically for all namespaces types. Namespaces may of course have additional unrelated counters and these are not altered. This work allows us to unify the type of the counters and reduces maintenance cost by moving the counter in one place and indicating that basic lifetime management is identical for all namespaces. - Peilin's fix adding three byte padding to Dmitry's PTRACE_GET_SYSCALL_INFO uapi struct to prevent an info leak. - Two smal patches to convert from the /* fall through */ comment annotation to the fallthrough keyword annotation which I had taken into my branch and into -next before df561f6688fe ("treewide: Use fallthrough pseudo-keyword") made it upstream which fixed this tree-wide. Since I didn't want to invalidate all testing for other commits I didn't rebase and kept them" * tag 'fixes-v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux: nsproxy: use put_nsproxy() in switch_task_namespaces() sys: Convert to the new fallthrough notation signal: Convert to the new fallthrough notation time: Use generic ns_common::count cgroup: Use generic ns_common::count mnt: Use generic ns_common::count user: Use generic ns_common::count pid: Use generic ns_common::count ipc: Use generic ns_common::count uts: Use generic ns_common::count net: Use generic ns_common::count ns: Add a common refcount into ns_common ptrace: Prevent kernel-infoleak in ptrace_get_syscall_info()
2020-10-01net-sysfs: Fix inconsistent of format with argument type in net-sysfs.cYe Bin1-2/+2
Fix follow warnings: [net/core/net-sysfs.c:1161]: (warning) %u in format string (no. 1) requires 'unsigned int' but the argument type is 'int'. [net/core/net-sysfs.c:1162]: (warning) %u in format string (no. 1) requires 'unsigned int' but the argument type is 'int'. Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: Ye Bin <yebin10@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-08-19net: Use generic ns_common::countChristian Brauner1-3/+3
Switch over network namespaces to use the newly introduced common lifetime counter. Network namespaces have an additional counter named "passive". This counter does not guarantee that the network namespace is not already de-initialized and so isn't concerned with the actual lifetime of the network namespace; only the "count" counter is. So the latter is moved into struct ns_common. Currently every namespace type has its own lifetime counter which is stored in the specific namespace struct. The lifetime counters are used identically for all namespaces types. Namespaces may of course have additional unrelated counters and these are not altered. This introduces a common lifetime counter into struct ns_common. The ns_common struct encompasses information that all namespaces share. That should include the lifetime counter since its common for all of them. It also allows us to unify the type of the counters across all namespaces. Most of them use refcount_t but one uses atomic_t and at least one uses kref. Especially the last one doesn't make much sense since it's just a wrapper around refcount_t since 2016 and actually complicates cleanup operations by having to use container_of() to cast the correct namespace struct out of struct ns_common. Having the lifetime counter for the namespaces in one place reduces maintenance cost. Not just because after switching all namespaces over we will have removed more code than we added but also because the logic is more easily understandable and we indicate to the user that the basic lifetime requirements for all namespaces are currently identical. Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com> Reviewed-by: Kees Cook <keescook@chromium.org> Acked-by: Christian Brauner <christian.brauner@ubuntu.com> [christian.brauner@ubuntu.com: rewrite commit] Link: https://lore.kernel.org/r/159644977635.604812.1319877322927063560.stgit@localhost.localdomain Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2020-08-12net: accept an empty mask in /sys/class/net/*/queues/rx-*/rps_cpusEric Dumazet1-5/+7
We must accept an empty mask in store_rps_map(), or we are not able to disable RPS on a queue. Fixes: 07bbecb34106 ("net: Restrict receive packets queuing to housekeeping CPUs") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Maciej Żenczykowski <maze@google.com> Cc: Alex Belits <abelits@marvell.com> Cc: Nitesh Narayan Lal <nitesh@redhat.com> Cc: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Maciej Żenczykowski <maze@google.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Nitesh Narayan Lal <nitesh@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-08-03Merge tag 'sched-core-2020-08-03' of ↵Linus Torvalds1-1/+9
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler updates from Ingo Molnar: - Improve uclamp performance by using a static key for the fast path - Add the "sched_util_clamp_min_rt_default" sysctl, to optimize for better power efficiency of RT tasks on battery powered devices. (The default is to maximize performance & reduce RT latencies.) - Improve utime and stime tracking accuracy, which had a fixed boundary of error, which created larger and larger relative errors as the values become larger. This is now replaced with more precise arithmetics, using the new mul_u64_u64_div_u64() helper in math64.h. - Improve the deadline scheduler, such as making it capacity aware - Improve frequency-invariant scheduling - Misc cleanups in energy/power aware scheduling - Add sched_update_nr_running tracepoint to track changes to nr_running - Documentation additions and updates - Misc cleanups and smaller fixes * tag 'sched-core-2020-08-03' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (54 commits) sched/doc: Factorize bits between sched-energy.rst & sched-capacity.rst sched/doc: Document capacity aware scheduling sched: Document arch_scale_*_capacity() arm, arm64: Fix selection of CONFIG_SCHED_THERMAL_PRESSURE Documentation/sysctl: Document uclamp sysctl knobs sched/uclamp: Add a new sysctl to control RT default boost value sched/uclamp: Fix a deadlock when enabling uclamp static key sched: Remove duplicated tick_nohz_full_enabled() check sched: Fix a typo in a comment sched/uclamp: Remove unnecessary mutex_init() arm, arm64: Select CONFIG_SCHED_THERMAL_PRESSURE sched: Cleanup SCHED_THERMAL_PRESSURE kconfig entry arch_topology, sched/core: Cleanup thermal pressure definition trace/events/sched.h: fix duplicated word linux/sched/mm.h: drop duplicated words in comments smp: Fix a potential usage of stale nr_cpus sched/fair: update_pick_idlest() Select group with lowest group_util when idle_cpus are equal sched: nohz: stop passing around unused "ticks" parameter. sched: Better document ttwu() sched: Add a tracepoint to track rq->nr_running ...
2020-07-21net-sysfs: add a newline when printing 'tx_timeout' by sysfsXiongfeng Wang1-1/+1
When I cat 'tx_timeout' by sysfs, it displays as follows. It's better to add a newline for easy reading. root@syzkaller:~# cat /sys/devices/virtual/net/lo/queues/tx-0/tx_timeout 0root@syzkaller:~# Signed-off-by: Xiongfeng Wang <wangxiongfeng2@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-08net: Restrict receive packets queuing to housekeeping CPUsAlex Belits1-1/+9
With the existing implementation of store_rps_map(), packets are queued in the receive path on the backlog queues of other CPUs irrespective of whether they are isolated or not. This could add a latency overhead to any RT workload that is running on the same CPU. Ensure that store_rps_map() only uses available housekeeping CPUs for storing the rps_map. Signed-off-by: Alex Belits <abelits@marvell.com> Signed-off-by: Nitesh Narayan Lal <nitesh@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20200625223443.2684-4-nitesh@redhat.com
2020-05-15net: core: recursively find netdev by device nodeTobias Waldekranz1-5/+5
The assumption that a device node is associated either with the netdev's device, or the parent of that device, does not hold for all drivers. E.g. Freescale's DPAA has two layers of platform devices above the netdev. Instead, recursively walk up the tree from the netdev, allowing any parent to match against the sought after node. Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>