Introduce getsockopt(TCP_AO_GET_KEYS) that lets a user get TCP-AO keys
and their properties from a socket. The user can provide a filter
to match the specific key to be dumped or ::get_all = 1 may be
used to dump all keys in one syscall.
Add another getsockopt(TCP_AO_INFO) for providing per-socket/per-ao_info
stats: packet counters, Current_key/RNext_key and flags like
::ao_required and ::accept_icmps.
Co-developed-by: Francesco Ruggeri <fruggeri@arista.com>
Signed-off-by: Francesco Ruggeri <fruggeri@arista.com>
Co-developed-by: Salam Noureddine <noureddine@arista.com>
Signed-off-by: Salam Noureddine <noureddine@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Acked-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Provide setsockopt() key flag that makes TCP-AO exclude hashing TCP
header for peers that match the key. This is needed for interraction
with middleboxes that may change TCP options, see RFC5925 (9.2).
Co-developed-by: Francesco Ruggeri <fruggeri@arista.com>
Signed-off-by: Francesco Ruggeri <fruggeri@arista.com>
Co-developed-by: Salam Noureddine <noureddine@arista.com>
Signed-off-by: Salam Noureddine <noureddine@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Acked-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Similarly to IPsec, RFC5925 prescribes:
">> A TCP-AO implementation MUST default to ignore incoming ICMPv4
messages of Type 3 (destination unreachable), Codes 2-4 (protocol
unreachable, port unreachable, and fragmentation needed -- ’hard
errors’), and ICMPv6 Type 1 (destination unreachable), Code 1
(administratively prohibited) and Code 4 (port unreachable) intended
for connections in synchronized states (ESTABLISHED, FIN-WAIT-1, FIN-
WAIT-2, CLOSE-WAIT, CLOSING, LAST-ACK, TIME-WAIT) that match MKTs."
A selftest (later in patch series) verifies that this attack is not
possible in this TCP-AO implementation.
Co-developed-by: Francesco Ruggeri <fruggeri@arista.com>
Signed-off-by: Francesco Ruggeri <fruggeri@arista.com>
Co-developed-by: Salam Noureddine <noureddine@arista.com>
Signed-off-by: Salam Noureddine <noureddine@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Acked-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Introduce segment counters that are useful for troubleshooting/debugging
as well as for writing tests.
Now there are global snmp counters as well as per-socket and per-key.
Co-developed-by: Francesco Ruggeri <fruggeri@arista.com>
Signed-off-by: Francesco Ruggeri <fruggeri@arista.com>
Co-developed-by: Salam Noureddine <noureddine@arista.com>
Signed-off-by: Salam Noureddine <noureddine@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Acked-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add 3 setsockopt()s:
1. TCP_AO_ADD_KEY to add a new Master Key Tuple (MKT) on a socket
2. TCP_AO_DEL_KEY to delete present MKT from a socket
3. TCP_AO_INFO to change flags, Current_key/RNext_key on a TCP-AO sk
Userspace has to introduce keys on every socket it wants to use TCP-AO
option on, similarly to TCP_MD5SIG/TCP_MD5SIG_EXT.
RFC5925 prohibits definition of MKTs that would match the same peer,
so do sanity checks on the data provided by userspace. Be as
conservative as possible, including refusal of defining MKT on
an established connection with no AO, removing the key in-use and etc.
(1) and (2) are to be used by userspace key manager to add/remove keys.
(3) main purpose is to set RNext_key, which (as prescribed by RFC5925)
is the KeyID that will be requested in TCP-AO header from the peer to
sign their segments with.
At this moment the life of ao_info ends in tcp_v4_destroy_sock().
Co-developed-by: Francesco Ruggeri <fruggeri@arista.com>
Signed-off-by: Francesco Ruggeri <fruggeri@arista.com>
Co-developed-by: Salam Noureddine <noureddine@arista.com>
Signed-off-by: Salam Noureddine <noureddine@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Acked-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
More than 1/3 of the n_gsm code has been contributed by us in the last
1.5 years, completing conformance with the standard and stabilizing the
driver:
- added UI (unnumbered information) frame support
- added PN (parameter negotiation) message handling and function support
- added optional keep-alive control link supervision via test messages
- added TIOCM_OUT1 and TIOCM_OUT2 to allow responder to operate as modem
- added TIOCMIWAIT support on virtual ttys
- added additional ioctls and parameters to configure the new functions
- added overall locking mechanism to avoid data race conditions
- added outgoing data flow to decouple physical from virtual tty handling
for better performance and to avoid dead-locks
- fixed advanced option mode implementation
- fixed convergence layer type 2 implementation
- fixed handling of CLD (multiplexer close down) messages
- fixed broken muxer close down procedure
- and many more bug fixes
With this most of our initial RFC has been implemented. It gives the driver
a quality boost unseen in the decade before.
Add a copyright notice to the n_gsm files to highlight this contribution.
Link: https://lore.kernel.org/all/20220225080758.2869-1-daniel.starke@siemens.com/
Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20231027053903.1886-1-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Kalle Valo says:
====================
wireless-next patches for v6.7
The third, and most likely the last, features pull request for v6.7.
Fixes all over and only few small new features.
Major changes:
iwlwifi
- more Multi-Link Operation (MLO) work
ath12k
- QCN9274: mesh support
ath11k
- firmware-2.bin container file format support
* tag 'wireless-next-2023-10-26' of git://git.kernel.org/pub/scm/linux/kernel/git/wireless/wireless-next: (155 commits)
wifi: ray_cs: Remove unnecessary (void*) conversions
Revert "wifi: ath11k: call ath11k_mac_fils_discovery() without condition"
wifi: ath12k: Introduce and use ath12k_sta_to_arsta()
wifi: ath12k: fix htt mlo-offset event locking
wifi: ath12k: fix dfs-radar and temperature event locking
wifi: ath11k: fix gtk offload status event locking
wifi: ath11k: fix htt pktlog locking
wifi: ath11k: fix dfs radar event locking
wifi: ath11k: fix temperature event locking
wifi: ath12k: rename the sc naming convention to ab
wifi: ath12k: rename the wmi_sc naming convention to wmi_ab
wifi: ath11k: add firmware-2.bin support
wifi: ath11k: qmi: refactor ath11k_qmi_m3_load()
wifi: rtw89: cleanup firmware elements parsing
wifi: rt2x00: rework MT7620 PA/LNA RF calibration
wifi: rt2x00: rework MT7620 channel config function
wifi: rt2x00: improve MT7620 register initialization
MAINTAINERS: wifi: rt2x00: drop Helmut Schaa
wifi: wlcore: main: replace deprecated strncpy with strscpy
wifi: wlcore: boot: replace deprecated strncpy with strscpy
...
====================
Link: https://lore.kernel.org/r/20231026090411.B2426C433CB@smtp.kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Daniel Borkmann says:
====================
pull-request: bpf-next 2023-10-26
We've added 51 non-merge commits during the last 10 day(s) which contain
a total of 75 files changed, 5037 insertions(+), 200 deletions(-).
The main changes are:
1) Add open-coded task, css_task and css iterator support.
One of the use cases is customizable OOM victim selection via BPF,
from Chuyi Zhou.
2) Fix BPF verifier's iterator convergence logic to use exact states
comparison for convergence checks, from Eduard Zingerman,
Andrii Nakryiko and Alexei Starovoitov.
3) Add BPF programmable net device where bpf_mprog defines the logic
of its xmit routine. It can operate in L3 and L2 mode,
from Daniel Borkmann and Nikolay Aleksandrov.
4) Batch of fixes for BPF per-CPU kptr and re-enable unit_size checking
for global per-CPU allocator, from Hou Tao.
5) Fix libbpf which eagerly assumed that SHT_GNU_verdef ELF section
was going to be present whenever a binary has SHT_GNU_versym section,
from Andrii Nakryiko.
6) Fix BPF ringbuf correctness to fold smp_mb__before_atomic() into
atomic_set_release(), from Paul E. McKenney.
7) Add a warning if NAPI callback missed xdp_do_flush() under
CONFIG_DEBUG_NET which helps checking if drivers were missing
the former, from Sebastian Andrzej Siewior.
8) Fix missed RCU read-lock in bpf_task_under_cgroup() which was throwing
a warning under sleepable programs, from Yafang Shao.
9) Avoid unnecessary -EBUSY from htab_lock_bucket by disabling IRQ before
checking map_locked, from Song Liu.
10) Make BPF CI linked_list failure test more robust,
from Kumar Kartikeya Dwivedi.
11) Enable samples/bpf to be built as PIE in Fedora, from Viktor Malik.
12) Fix xsk starving when multiple xsk sockets were associated with
a single xsk_buff_pool, from Albert Huang.
13) Clarify the signed modulo implementation for the BPF ISA standardization
document that it uses truncated division, from Dave Thaler.
14) Improve BPF verifier's JEQ/JNE branch taken logic to also consider
signed bounds knowledge, from Andrii Nakryiko.
15) Add an option to XDP selftests to use multi-buffer AF_XDP
xdp_hw_metadata and mark used XDP programs as capable to use frags,
from Larysa Zaremba.
16) Fix bpftool's BTF dumper wrt printing a pointer value and another
one to fix struct_ops dump in an array, from Manu Bretelle.
* tag 'for-netdev' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (51 commits)
netkit: Remove explicit active/peer ptr initialization
selftests/bpf: Fix selftests broken by mitigations=off
samples/bpf: Allow building with custom bpftool
samples/bpf: Fix passing LDFLAGS to libbpf
samples/bpf: Allow building with custom CFLAGS/LDFLAGS
bpf: Add more WARN_ON_ONCE checks for mismatched alloc and free
selftests/bpf: Add selftests for netkit
selftests/bpf: Add netlink helper library
bpftool: Extend net dump with netkit progs
bpftool: Implement link show support for netkit
libbpf: Add link-based API for netkit
tools: Sync if_link uapi header
netkit, bpf: Add bpf programmable net device
bpf: Improve JEQ/JNE branch taken logic
bpf: Fold smp_mb__before_atomic() into atomic_set_release()
bpf: Fix unnecessary -EBUSY from htab_lock_bucket
xsk: Avoid starving the xsk further down the list
bpf: print full verifier states on infinite loop detection
selftests/bpf: test if state loops are detected in a tricky case
bpf: correct loop detection for iterators convergence
...
====================
Link: https://lore.kernel.org/r/20231026150509.2824-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Add network rules support in the ruleset management helpers and the
landlock_create_ruleset() syscall. Extend user space API to support
network actions:
* Add new network access rights: LANDLOCK_ACCESS_NET_BIND_TCP and
LANDLOCK_ACCESS_NET_CONNECT_TCP.
* Add a new network rule type: LANDLOCK_RULE_NET_PORT tied to struct
landlock_net_port_attr. The allowed_access field contains the network
access rights, and the port field contains the port value according to
the controlled protocol. This field can take up to a 64-bit value
but the maximum value depends on the related protocol (e.g. 16-bit
value for TCP). Network port is in host endianness [1].
* Add a new handled_access_net field to struct landlock_ruleset_attr
that contains network access rights.
* Increment the Landlock ABI version to 4.
Implement socket_bind() and socket_connect() LSM hooks, which enable
to control TCP socket binding and connection to specific ports.
Expand access_masks_t from u16 to u32 to be able to store network access
rights alongside filesystem access rights for rulesets' handled access
rights.
Access rights are not tied to socket file descriptors but checked at
bind() or connect() call time against the caller's Landlock domain. For
the filesystem, a file descriptor is a direct access to a file/data.
However, for network sockets, we cannot identify for which data or peer
a newly created socket will give access to. Indeed, we need to wait for
a connect or bind request to identify the use case for this socket.
Likewise a directory file descriptor may enable to open another file
(i.e. a new data item), but this opening is also restricted by the
caller's domain, not the file descriptor's access rights [2].
[1] https://lore.kernel.org/r/278ab07f-7583-a4e0-3d37-1bacd091531d@digikod.net
[2] https://lore.kernel.org/r/263c1eb3-602f-57fe-8450-3f138581bee7@digikod.net
Signed-off-by: Konstantin Meskhidze <konstantin.meskhidze@huawei.com>
Link: https://lore.kernel.org/r/20231026014751.414649-9-konstantin.meskhidze@huawei.com
[mic: Extend commit message, fix typo in comments, and specify
endianness in the documentation]
Co-developed-by: Mickaël Salaün <mic@digikod.net>
Signed-off-by: Mickaël Salaün <mic@digikod.net>
When remapping hardware is configured by system software in scalable mode
as Nested (PGTT=011b) and with PWSNP field Set in the PASID-table-entry,
it may Set Accessed bit and Dirty bit (and Extended Access bit if enabled)
in first-stage page-table entries even when second-stage mappings indicate
that corresponding first-stage page-table is Read-Only.
As the result, contents of pages designated by VMM as Read-Only can be
modified by IOMMU via PML5E (PML4E for 4-level tables) access as part of
address translation process due to DMAs issued by Guest.
This disallows read-only mappings in the domain that is supposed to be used
as nested parent. Reference from Sapphire Rapids Specification Update [1],
errata details, SPR17. Userspace should know this limitation by checking
the IOMMU_HW_INFO_VTD_ERRATA_772415_SPR17 flag reported in the IOMMU_GET_HW_INFO
ioctl.
[1] https://www.intel.com/content/www/us/en/content-details/772415/content-details.html
Link: https://lore.kernel.org/r/20231026044216.64964-9-yi.l.liu@intel.com
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
IOMMU_HWPT_ALLOC already supports iommu_domain allocation for usersapce.
But it can only allocate a hw_pagetable that associates to a given IOAS,
i.e. only a kernel-managed hw_pagetable of IOMMUFD_OBJ_HWPT_PAGING type.
IOMMU drivers can now support user-managed hw_pagetables, for two-stage
translation use cases that require user data input from the user space.
Add a new IOMMUFD_OBJ_HWPT_NESTED type with its abort/destroy(). Pair it
with a new iommufd_hwpt_nested structure and its to_hwpt_nested() helper.
Update the to_hwpt_paging() helper, so a NESTED-type hw_pagetable can be
handled in the callers, for example iommufd_hw_pagetable_enforce_rr().
Screen the inputs including the parent PAGING-type hw_pagetable that has
a need of a new nest_parent flag in the iommufd_hwpt_paging structure.
Extend the IOMMU_HWPT_ALLOC ioctl to accept an IOMMU driver specific data
input which is tagged by the enum iommu_hwpt_data_type. Also, update the
@pt_id to accept hwpt_id too besides an ioas_id. Then, use them to allocate
a hw_pagetable of IOMMUFD_OBJ_HWPT_NESTED type using the
iommufd_hw_pagetable_alloc_nested() allocator.
Link: https://lore.kernel.org/r/20231026043938.63898-8-yi.l.liu@intel.com
Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
Co-developed-by: Yi Liu <yi.l.liu@intel.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
This work adds a new, minimal BPF-programmable device called "netkit"
(former PoC code-name "meta") we recently presented at LSF/MM/BPF. The
core idea is that BPF programs are executed within the drivers xmit routine
and therefore e.g. in case of containers/Pods moving BPF processing closer
to the source.
One of the goals was that in case of Pod egress traffic, this allows to
move BPF programs from hostns tcx ingress into the device itself, providing
earlier drop or forward mechanisms, for example, if the BPF program
determines that the skb must be sent out of the node, then a redirect to
the physical device can take place directly without going through per-CPU
backlog queue. This helps to shift processing for such traffic from softirq
to process context, leading to better scheduling decisions/performance (see
measurements in the slides).
In this initial version, the netkit device ships as a pair, but we plan to
extend this further so it can also operate in single device mode. The pair
comes with a primary and a peer device. Only the primary device, typically
residing in hostns, can manage BPF programs for itself and its peer. The
peer device is designated for containers/Pods and cannot attach/detach
BPF programs. Upon the device creation, the user can set the default policy
to 'pass' or 'drop' for the case when no BPF program is attached.
Additionally, the device can be operated in L3 (default) or L2 mode. The
management of BPF programs is done via bpf_mprog, so that multi-attach is
supported right from the beginning with similar API and dependency controls
as tcx. For details on the latter see commit 053c8e1f23 ("bpf: Add generic
attach/detach/query API for multi-progs"). tc BPF compatibility is provided,
so that existing programs can be easily migrated.
Going forward, we plan to use netkit devices in Cilium as the main device
type for connecting Pods. They will be operated in L3 mode in order to
simplify a Pod's neighbor management and the peer will operate in default
drop mode, so that no traffic is leaving between the time when a Pod is
brought up by the CNI plugin and programs attached by the agent.
Additionally, the programs we attach via tcx on the physical devices are
using bpf_redirect_peer() for inbound traffic into netkit device, hence the
latter is also supporting the ndo_get_peer_dev callback. Similarly, we use
bpf_redirect_neigh() for the way out, pushing from netkit peer to phys device
directly. Also, BIG TCP is supported on netkit device. For the follow-up
work in single device mode, we plan to convert Cilium's cilium_host/_net
devices into a single one.
An extensive test suite for checking device operations and the BPF program
and link management API comes as BPF selftests in this series.
Co-developed-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com>
Acked-by: Stanislav Fomichev <sdf@google.com>
Acked-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://github.com/borkmann/iproute2/tree/pr/netkit
Link: http://vger.kernel.org/bpfconf2023_material/tcx_meta_netdev_borkmann.pdf (24ff.)
Link: https://lore.kernel.org/r/20231024214904.29825-2-daniel@iogearbox.net
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
in the current MPTCP control plane, all operations use a netlink
attribute of the same type "MPTCP_PM_ATTR". However, add/del/get/flush
operations only parse the first element in the message _ the one that
describes MPTCP endpoints (that was named MPTCP_PM_ATTR_ADDR and
mostly used in ADD_ADDR operations _ probably the similarity of "attr",
"addr" and "add" might cause some confusion to human readers).
Convert MPTCP from 'small_ops' to 'ops', thus allowing different attributes
for each single operation, hopefully makes all this clearer to human
readers.
- use a separate attribute set for add/del/get/flush address operation,
binary compatible with the existing one, to store the endpoint address.
MPTCP_PM_ENDPOINT_ADDR is added to the uAPI (with the same value as
MPTCP_PM_ATTR_ADDR) for these operations.
- convert mptcp_pm_ops[] and add policy files accordingly.
this prepares MPTCP control plane to be described as YAML spec.
Link: https://github.com/multipath-tcp/mptcp_net-next/issues/340
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: Mat Martineau <martineau@kernel.org>
Link: https://lore.kernel.org/r/20231023-send-net-next-20231023-1-v2-3-16b1f701f900@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Convert open-coded variants of PCI field access into FIELD_GET/PREP()
to make the code easier to understand.
Add two missing defines into pci_regs.h. Logically, the Max No-Snoop
Latency Register is a separate word sized register in the PCIe spec,
but the pre-existing LTR defines in pci_regs.h with dword long values
seem to consider the registers together (the same goes for the only
user). Thus, follow the custom and make the new values also take both
word long LTR registers as a joint dword register.
Link: https://lore.kernel.org/r/20231024110336.26264-1-ilpo.jarvinen@linux.intel.com
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
VFIO has an operation where it unmaps an IOVA while returning a bitmap with
the dirty data. In reality the operation doesn't quite query the IO
pagetables that the PTE was dirty or not. Instead it marks as dirty on
anything that was mapped, and doing so in one syscall.
In IOMMUFD the equivalent is done in two operations by querying with
GET_DIRTY_IOVA followed by UNMAP_IOVA. However, this would incur two TLB
flushes given that after clearing dirty bits IOMMU implementations require
invalidating their IOTLB, plus another invalidation needed for the UNMAP.
To allow dirty bits to be queried faster, add a flag
(IOMMU_HWPT_GET_DIRTY_BITMAP_NO_CLEAR) that requests to not clear the dirty
bits from the PTE (but just reading them), under the expectation that the
next operation is the unmap. An alternative is to unmap and just
perpectually mark as dirty as that's the same behaviour as today. So here
equivalent functionally can be provided with unmap alone, and if real dirty
info is required it will amortize the cost while querying.
There's still a race against DMA where in theory the unmap of the IOVA
(when the guest invalidates the IOTLB via emulated iommu) would race
against the VF performing DMA on the same IOVA. As discussed in [0], we are
accepting to resolve this race as throwing away the DMA and it doesn't
matter if it hit physical DRAM or not, the VM can't tell if we threw it
away because the DMA was blocked or because we failed to copy the DRAM.
[0] https://lore.kernel.org/linux-iommu/20220502185239.GR8364@nvidia.com/
Link: https://lore.kernel.org/r/20231024135109.73787-10-joao.m.martins@oracle.com
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Connect a hw_pagetable to the IOMMU core dirty tracking
read_and_clear_dirty iommu domain op. It exposes all of the functionality
for the UAPI that read the dirtied IOVAs while clearing the Dirty bits from
the PTEs.
In doing so, add an IO pagetable API iopt_read_and_clear_dirty_data() that
performs the reading of dirty IOPTEs for a given IOVA range and then
copying back to userspace bitmap.
Underneath it uses the IOMMU domain kernel API which will read the dirty
bits, as well as atomically clearing the IOPTE dirty bit and flushing the
IOTLB at the end. The IOVA bitmaps usage takes care of the iteration of the
bitmaps user pages efficiently and without copies. Within the iterator
function we iterate over io-pagetable contigous areas that have been
mapped.
Contrary to past incantation of a similar interface in VFIO the IOVA range
to be scanned is tied in to the bitmap size, thus the application needs to
pass a appropriately sized bitmap address taking into account the iova
range being passed *and* page size ... as opposed to allowing bitmap-iova
!= iova.
Link: https://lore.kernel.org/r/20231024135109.73787-8-joao.m.martins@oracle.com
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Every IOMMU driver should be able to implement the needed iommu domain ops
to control dirty tracking.
Connect a hw_pagetable to the IOMMU core dirty tracking ops, specifically
the ability to enable/disable dirty tracking on an IOMMU domain
(hw_pagetable id). To that end add an io_pagetable kernel API to toggle
dirty tracking:
* iopt_set_dirty_tracking(iopt, [domain], state)
The intended caller of this is via the hw_pagetable object that is created.
Internally it will ensure the leftover dirty state is cleared /right
before/ dirty tracking starts. This is also useful for iommu drivers which
may decide that dirty tracking is always-enabled at boot without wanting to
toggle dynamically via corresponding iommu domain op.
Link: https://lore.kernel.org/r/20231024135109.73787-7-joao.m.martins@oracle.com
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Throughout IOMMU domain lifetime that wants to use dirty tracking, some
guarantees are needed such that any device attached to the iommu_domain
supports dirty tracking.
The idea is to handle a case where IOMMU in the system are assymetric
feature-wise and thus the capability may not be supported for all devices.
The enforcement is done by adding a flag into HWPT_ALLOC namely:
IOMMU_HWPT_ALLOC_DIRTY_TRACKING
.. Passed in HWPT_ALLOC ioctl() flags. The enforcement is done by creating
a iommu_domain via domain_alloc_user() and validating the requested flags
with what the device IOMMU supports (and failing accordingly) advertised).
Advertising the new IOMMU domain feature flag requires that the individual
iommu driver capability is supported when a future device attachment
happens.
Link: https://lore.kernel.org/r/20231024135109.73787-6-joao.m.martins@oracle.com
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Subtract one to __GTPA_MAX, otherwise GTPA_MAX is off by 2.
Fixes: 459aa660eb ("gtp: add initial driver for datapath of GPRS Tunneling Protocol (GTP-U)")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Add the ability to report in tcp_info.tcpi_options if
a flow is using usec resolution in TCP TS val.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This new dst feature flag will be used to allow TCP to use usec
based timestamps instead of msec ones.
ip route .... feature tcp_usec_ts
Also document that RTAX_FEATURE_SACK and RTAX_FEATURE_TIMESTAMP
are unused.
RTAX_FEATURE_ALLFRAG is also going away soon.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The IOMMU_HWPT_ALLOC_NEST_PARENT flag is used to allocate a HWPT. Though
a HWPT holds a domain in the core structure, it is still quite confusing
to describe it using "domain" in the uAPI kdoc. Correct it to "HWPT".
Fixes: 4ff5421633 ("iommufd: Support allocating nested parent domain")
Link: https://lore.kernel.org/r/20231017181552.12667-1-nicolinc@nvidia.com
Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Reproduce environment:
network with 3 VM linuxs is connected as below:
VM1<---->VM2(latest kernel 6.5.0-rc7)<---->VM3
VM1: eth0 ip: 192.168.122.207 MTU 1500
VM2: eth0 ip: 192.168.122.208, eth1 ip: 192.168.123.224 MTU 1500
VM3: eth0 ip: 192.168.123.240 MTU 1500
Reproduce:
VM1 send 1400 bytes UDP data to VM3 using tools scapy with flags=0.
scapy command:
send(IP(dst="192.168.123.240",flags=0)/UDP()/str('0'*1400),count=1,
inter=1.000000)
Result:
Before IP data is sent.
----------------------------------------------------------------------
root@qemux86-64:~# cat /proc/net/snmp
Ip: Forwarding DefaultTTL InReceives InHdrErrors InAddrErrors
ForwDatagrams InUnknownProtos InDiscards InDelivers OutRequests
OutDiscards OutNoRoutes ReasmTimeout ReasmReqds ReasmOKs ReasmFails
FragOKs FragFails FragCreates
Ip: 1 64 11 0 3 4 0 0 4 7 0 0 0 0 0 0 0 0 0
......
----------------------------------------------------------------------
After IP data is sent.
----------------------------------------------------------------------
root@qemux86-64:~# cat /proc/net/snmp
Ip: Forwarding DefaultTTL InReceives InHdrErrors InAddrErrors
ForwDatagrams InUnknownProtos InDiscards InDelivers OutRequests
OutDiscards OutNoRoutes ReasmTimeout ReasmReqds ReasmOKs ReasmFails
FragOKs FragFails FragCreates
Ip: 1 64 12 0 3 5 0 0 4 8 0 0 0 0 0 0 0 0 0
......
----------------------------------------------------------------------
"ForwDatagrams" increase from 4 to 5 and "OutRequests" also increase
from 7 to 8.
Issue description and patch:
IPSTATS_MIB_OUTPKTS("OutRequests") is counted with IPSTATS_MIB_OUTOCTETS
("OutOctets") in ip_finish_output2().
According to RFC 4293, it is "OutOctets" counted with "OutTransmits" but
not "OutRequests". "OutRequests" does not include any datagrams counted
in "ForwDatagrams".
ipSystemStatsOutOctets OBJECT-TYPE
DESCRIPTION
"The total number of octets in IP datagrams delivered to the
lower layers for transmission. Octets from datagrams
counted in ipIfStatsOutTransmits MUST be counted here.
ipSystemStatsOutRequests OBJECT-TYPE
DESCRIPTION
"The total number of IP datagrams that local IP user-
protocols (including ICMP) supplied to IP in requests for
transmission. Note that this counter does not include any
datagrams counted in ipSystemStatsOutForwDatagrams.
So do patch to define IPSTATS_MIB_OUTPKTS to "OutTransmits" and add
IPSTATS_MIB_OUTREQUESTS for "OutRequests".
Add IPSTATS_MIB_OUTREQUESTS counter in __ip_local_out() for ipv4 and add
IPSTATS_MIB_OUT counter in ip6_finish_output2() for ipv6.
Test result with patch:
Before IP data is sent.
----------------------------------------------------------------------
root@qemux86-64:~# cat /proc/net/snmp
Ip: Forwarding DefaultTTL InReceives InHdrErrors InAddrErrors
ForwDatagrams InUnknownProtos InDiscards InDelivers OutRequests
OutDiscards OutNoRoutes ReasmTimeout ReasmReqds ReasmOKs ReasmFails
FragOKs FragFails FragCreates OutTransmits
Ip: 1 64 9 0 5 1 0 0 3 3 0 0 0 0 0 0 0 0 0 4
......
root@qemux86-64:~# cat /proc/net/netstat
......
IpExt: InNoRoutes InTruncatedPkts InMcastPkts OutMcastPkts InBcastPkts
OutBcastPkts InOctets OutOctets InMcastOctets OutMcastOctets
InBcastOctets OutBcastOctets InCsumErrors InNoECTPkts InECT1Pkts
InECT0Pkts InCEPkts ReasmOverlaps
IpExt: 0 0 0 0 0 0 2976 1896 0 0 0 0 0 9 0 0 0 0
----------------------------------------------------------------------
After IP data is sent.
----------------------------------------------------------------------
root@qemux86-64:~# cat /proc/net/snmp
Ip: Forwarding DefaultTTL InReceives InHdrErrors InAddrErrors
ForwDatagrams InUnknownProtos InDiscards InDelivers OutRequests
OutDiscards OutNoRoutes ReasmTimeout ReasmReqds ReasmOKs ReasmFails
FragOKs FragFails FragCreates OutTransmits
Ip: 1 64 10 0 5 2 0 0 3 3 0 0 0 0 0 0 0 0 0 5
......
root@qemux86-64:~# cat /proc/net/netstat
......
IpExt: InNoRoutes InTruncatedPkts InMcastPkts OutMcastPkts InBcastPkts
OutBcastPkts InOctets OutOctets InMcastOctets OutMcastOctets
InBcastOctets OutBcastOctets InCsumErrors InNoECTPkts InECT1Pkts
InECT0Pkts InCEPkts ReasmOverlaps
IpExt: 0 0 0 0 0 0 4404 3324 0 0 0 0 0 10 0 0 0 0
----------------------------------------------------------------------
"ForwDatagrams" increase from 1 to 2 and "OutRequests" is keeping 3.
"OutTransmits" increase from 4 to 5 and "OutOctets" increase 1428.
Signed-off-by: Heng Guo <heng.guo@windriver.com>
Reviewed-by: Kun Song <Kun.Song@windriver.com>
Reviewed-by: Filip Pudak <filip.pudak@windriver.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
We currently push everyone to use padding to align 64b values
in netlink. Un-padded nla_put_u64() doesn't even exist any more.
The story behind this possibly start with this thread:
https://lore.kernel.org/netdev/20121204.130914.1457976839967676240.davem@davemloft.net/
where DaveM was concerned about the alignment of a structure
containing 64b stats. If user space tries to access such struct
directly:
struct some_stats *stats = nla_data(attr);
printf("A: %llu", stats->a);
lack of alignment may become problematic for some architectures.
These days we most often put every single member in a separate
attribute, meaning that the code above would use a helper like
nla_get_u64(), which can deal with alignment internally.
Even for arches which don't have good unaligned access - access
aligned to 4B should be pretty efficient.
Kernel and well known libraries deal with unaligned input already.
Padded 64b is quite space-inefficient (64b + pad means at worst 16B
per attr vs 32b which takes 8B). It is also more typing:
if (nla_put_u64_pad(rsp, NETDEV_A_SOMETHING_SOMETHING,
value, NETDEV_A_SOMETHING_PAD))
Create a new attribute type which will use 32 bits at netlink
level if value is small enough (probably most of the time?),
and (4B-aligned) 64 bits otherwise. Kernel API is just:
if (nla_put_uint(rsp, NETDEV_A_SOMETHING_SOMETHING, value))
Calling this new type "just" sint / uint with no specific size
will hopefully also make people more comfortable with using it.
Currently telling people "don't use u8, you may need the bits,
and netlink will round up to 4B, anyway" is the #1 comment
we give to newcomers.
In terms of netlink layout it looks like this:
0 4 8 12 16
32b: [nlattr][ u32 ]
64b: [ pad ][nlattr][ u64 ]
uint(32) [nlattr][ u32 ]
uint(64) [nlattr][ u64 ]
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
William writes:
First set of Counter updates for the 6.7 cycle
A minor typographical error is fixed in the description comment block
for struct counter_component.
* tag 'counter-updates-for-6.7a' of git://git.kernel.org/pub/scm/linux/kernel/git/wbg/counter:
counter: chrdev: remove a typo in header file comment
Jonathan writes:
IIO: 1st set of new device support, features and cleanup for 6.7
Particularly great to see a resolver driver move out of staging via a
massive set of changes. Only took 13 years :)
One small patch added then reverted due to a report of test breakage
(ashai-kasei,ak8975: Drop deprecated enums.)
An immutable branch was used for some hid-senors changes in case
there was a need to take them into the HID tree as well.
New device support
-----------------
adi,hmc425a
- Add support for HMC540SLP3E broadband 4-bit digital attenuator.
kionix,kx022a
- Add support for the kx132-1211 accelerometer. Require significant
driver rework to enable this including add a chip type specific
structure to deal with the chip differences.
- Add support for the kx132acr-lbz accelerometer (subset of the kx022a
feature set).
lltc,ltc2309
- New driver for this 8 channel ADC.
microchip,mcp3911
- Add support for rest of mcp391x family of ADCs (there are various
differences beyond simple channel count variation.
Series includes some general driver cleanup.
microchip,mcp3564
- New driver for MCP3461, MCP3462, MCP3464, MCP3541, MCP3562, MCP3564
and their R variants of 16/24bit ADCs. A few minor fixed followed.
rohm,bu1390
- New driver for this pressure sensor.
Staging graduation
------------------
adi,ad1210 (after 13 or so years :)
- More or less a complete (step-wise) rewrite of this resolver driver
to bring it up to date with modern IIO standards. The fault signal
handling mapping to event channels was particularly complex and
significant part of the changes.
Features
--------
iio-core
- Add chromacity and color temperature channel types.
adi,ad7192
- Oversampling ratio control (called fast settling in datasheet).
adi,adis16475
- Add core support and then driver support for delta angle and delta
velocity channels. These are intended for summation to establish
angle and velocity changes over larger timescales. Fix was
needed for alignment after the temperature channel. Further fix
reduced set of devices for which the buffer support was applicable
as seems burst reads don't cover these on all devices.
hid-sensors-als
- Chromacity and color temperatures support including in amd sfh.
stx104
- Add support for counter subsystem to this multipurpose device.
ti,twl6030
- Add missing device tree binding description.
Clean up and minor fixes.
------------------------
treewide
- Drop some unused declarations across IIO.
- Make more use of device_get_match_data() instead of OF specific
approaches.
Similar cleanup to sets of drivers.
- Stop platform remove callbacks returning anything by using the
temporary remove_new() callback.
- Use i2c_get_match_data() to cope nicely with all types of ID table
entry.
- Use device_get_match_data() for various platform device to cope
with more types of firmware.
- Convert from enum to pointer in ID tables allowing use of
i2c_get_match_data().
- Fix sorting on some ID tables.
- Include specific string helper headers rather than simply string_helpers.h
docs
- Better description of the ordering requirements etc for
available_scan_masks.
tools
- Handle alignment of mixed sizes where the last element isn't the biggest
correctly. Seems that doesn't happen often!
adi,ad2s1210
- Lots of work from David Lechner on this driver including a few fixes
that are going with the rework to avoid slowing that down.
adi,ad4310
- Replace deprecated devm_clk_register()
adi,ad74413r
- Bring the channel function setting inline with the datasheet.
adi,ad7192
- Change to FIELD_PREP(), FIELD_GET().
- Calculate f_order from the sinc filter and chop filter states.
- Move more per chip config into data in struct ad7192_chip_info
- Cleanup unused parameter in channel macros.
adi,adf4350
- Make use of devm_* to simplify error handling for many of the setup
calls in probe() / tear down in remove() and error paths. Some more
work to be done on this one.
- Use dev_err_probe() for errors in probe() callback.
adi,adf4413
- Typo in function name prefix.
adi,adxl345
- Add channel scale to the chip type specific structure and drop
using a type field previously used for indirection.
asahi,ak8985
- Fix a mismatch introduced when switching from enum->pointers
in the match tables.
amlogic,meson
- Expand error logging during probe.
invensense,mpu6050
- Support level-shifter control. Whilst no one is sure exactly what this
is doing it is needed for some old boards.
- Document mount-matrix dt-binding.
mediatek,mt6577
- Use devm_clk_get_enabled() to replace open coded version and move
everything over to being device managed. Drop now empty remove()
callback. Fix follows to put the drvdata back.
- Use dev_err_probe() for error reporting in probe() callback.
memsic,mxc4005
- Add of_match_table.
microchip,mcp4725
- Move various chip specific data from being looked up by chip ID to
data in the chip type specific structure.
silicon-labs,si7005
- Add of_match_table and entry in trivial-devices.yaml
st,lsm6dsx
- Add missing mount-matrix dt binding documentation.
st,spear
- Use devm_clk_get_enabled() and some other devm calls to move everything
over to being device managed. Drop now empty remove() callback.
- Use dev_err_probe() to better handled deferred probing and tidy up
error reporting in probe() callback.
st,stm32-adc
- Add a bit of additional checking in probe() to protect against a NULL
pointer (no known path to trigger it today).
- Replace deprecated strncpy()
ti,ads1015
- Allow for edge triggers.
- Document interrupt in dt-bindings.
* tag 'iio-for-6.7a' of https://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio: (201 commits)
iio: Use device_get_match_data()
iio: adc: MCP3564: fix warn: unsigned '__x' is never less than zero.
dt-bindings: trivial-devices: add silabs,si7005
iio: si7005: Add device tree support
drivers: imu: adis16475.c: Remove scan index from delta channels
dt-bindings: iio: imu: st,lsm6dsx: add mount-matrix property
iio: resolver: ad2s1210: remove of_match_ptr()
iio: resolver: ad2s1210: remove DRV_NAME macro
iio: resolver: ad2s1210: move out of staging
staging: iio: resolver: ad2s1210: simplify code with guard(mutex)
staging: iio: resolver: ad2s1210: clear faults after soft reset
staging: iio: resolver: ad2s1210: refactor sample toggle
staging: iio: resolver: ad2s1210: remove fault attribute
staging: iio: resolver: ad2s1210: add label attribute support
staging: iio: resolver: ad2s1210: add register/fault support summary
staging: iio: resolver: ad2s1210: implement fault events
iio: event: add optional event label support
staging: iio: resolver: ad2s1210: rename DOS reset min/max attrs
staging: iio: resolver: ad2s1210: convert DOS mismatch threshold to event attr
staging: iio: resolver: ad2s1210: convert DOS overrange threshold to event attr
...
The sevguest driver was a first mover in the confidential computing
space. As a first mover that afforded some leeway to build the driver
without concern for common infrastructure.
Now that sevguest is no longer a singleton [1] the common operation of
building and transmitting attestation report blobs can / should be made
common. In this model the so called "TSM-provider" implementations can
share a common envelope ABI even if the contents of that envelope remain
vendor-specific. When / if the industry agrees on an attestation record
format, that definition can also fit in the same ABI. In the meantime
the kernel's maintenance burden is reduced and collaboration on the
commons is increased.
Convert sevguest to use CONFIG_TSM_REPORTS to retrieve the data that
the SNP_GET_EXT_REPORT ioctl produces. An example flow follows for
retrieving the report blob via the TSM interface utility,
assuming no nonce and VMPL==2:
report=/sys/kernel/config/tsm/report/report0
mkdir $report
echo 2 > $report/privlevel
dd if=/dev/urandom bs=64 count=1 > $report/inblob
hexdump -C $report/outblob # SNP report
hexdump -C $report/auxblob # cert_table
rmdir $report
Given that the platform implementation is free to return empty
certificate data if none is available it lets configfs-tsm be simplified
as it only needs to worry about wrapping SNP_GET_EXT_REPORT, and leave
SNP_GET_REPORT alone.
The old ioctls can be lazily deprecated, the main motivation of this
effort is to stop the proliferation of new ioctls, and to increase
cross-vendor collaboration.
Link: http://lore.kernel.org/r/64961c3baf8ce_142af829436@dwillia2-xfh.jf.intel.com.notmuch [1]
Cc: Borislav Petkov <bp@alien8.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Dionna Glaze <dionnaglaze@google.com>
Cc: Jeremi Piotrowski <jpiotrowski@linux.microsoft.com>
Tested-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Tested-by: Alexey Kardashevskiy <aik@amd.com>
Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Add initial support for SOCKET_URING_OP_SETSOCKOPT. This new command is
similar to setsockopt. This implementation leverages the function
do_sock_setsockopt(), which is shared with the setsockopt() system call
path.
Important to say that userspace needs to keep the pointer's memory alive
until the operation is completed. I.e, the memory could not be
deallocated before the CQE is returned to userspace.
Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Gabriel Krisman Bertazi <krisman@suse.de>
Link: https://lore.kernel.org/r/20231016134750.1381153-11-leitao@debian.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add support for getsockopt command (SOCKET_URING_OP_GETSOCKOPT), where
level is SOL_SOCKET. This is leveraging the sockptr_t infrastructure,
where a sockptr_t is either userspace or kernel space, and handled as
such.
Differently from the getsockopt(2), the optlen field is not a userspace
pointers. In getsockopt(2), userspace provides optlen pointer, which is
overwritten by the kernel. In this implementation, userspace passes a
u32, and the new value is returned in cqe->res. I.e., optlen is not a
pointer.
Important to say that userspace needs to keep the pointer alive until
the CQE is completed.
Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Gabriel Krisman Bertazi <krisman@suse.de>
Link: https://lore.kernel.org/r/20231016134750.1381153-10-leitao@debian.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The PAGEMAP_SCAN IOCTL on the pagemap file can be used to get or optionally
clear the info about page table entries. The following operations are
supported in this IOCTL:
- Scan the address range and get the memory ranges matching the provided
criteria. This is performed when the output buffer is specified.
- Write-protect the pages. The PM_SCAN_WP_MATCHING is used to write-protect
the pages of interest. The PM_SCAN_CHECK_WPASYNC aborts the operation if
non-Async Write Protected pages are found. The ``PM_SCAN_WP_MATCHING``
can be used with or without PM_SCAN_CHECK_WPASYNC.
- Both of those operations can be combined into one atomic operation where
we can get and write protect the pages as well.
Following flags about pages are currently supported:
- PAGE_IS_WPALLOWED - Page has async-write-protection enabled
- PAGE_IS_WRITTEN - Page has been written to from the time it was write protected
- PAGE_IS_FILE - Page is file backed
- PAGE_IS_PRESENT - Page is present in the memory
- PAGE_IS_SWAPPED - Page is in swapped
- PAGE_IS_PFNZERO - Page has zero PFN
- PAGE_IS_HUGE - Page is THP or Hugetlb backed
This IOCTL can be extended to get information about more PTE bits. The
entire address range passed by user [start, end) is scanned until either
the user provided buffer is full or max_pages have been found.
[akpm@linux-foundation.org: update it for "mm: hugetlb: add huge page size param to set_huge_pte_at()"]
[akpm@linux-foundation.org: fix CONFIG_HUGETLB_PAGE=n warning]
[arnd@arndb.de: hide unused pagemap_scan_backout_range() function]
Link: https://lkml.kernel.org/r/20230927060257.2975412-1-arnd@kernel.org
[sfr@canb.auug.org.au: fix "fs/proc/task_mmu: hide unused pagemap_scan_backout_range() function"]
Link: https://lkml.kernel.org/r/20230928092223.0625c6bf@canb.auug.org.au
Link: https://lkml.kernel.org/r/20230821141518.870589-3-usama.anjum@collabora.com
Signed-off-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Reviewed-by: Andrei Vagin <avagin@gmail.com>
Reviewed-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Cc: Alex Sierra <alex.sierra@amd.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Gustavo A. R. Silva <gustavoars@kernel.org>
Cc: "Liam R. Howlett" <Liam.Howlett@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michal Miroslaw <emmir@google.com>
Cc: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: Nadav Amit <namit@vmware.com>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Paul Gofman <pgofman@codeweavers.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Yun Zhou <yun.zhou@windriver.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "Implement IOCTL to get and optionally clear info about
PTEs", v33.
*Motivation*
The real motivation for adding PAGEMAP_SCAN IOCTL is to emulate Windows
GetWriteWatch() and ResetWriteWatch() syscalls [1]. The GetWriteWatch()
retrieves the addresses of the pages that are written to in a region of
virtual memory.
This syscall is used in Windows applications and games etc. This syscall
is being emulated in pretty slow manner in userspace. Our purpose is to
enhance the kernel such that we translate it efficiently in a better way.
Currently some out of tree hack patches are being used to efficiently
emulate it in some kernels. We intend to replace those with these
patches. So the whole gaming on Linux can effectively get benefit from
this. It means there would be tons of users of this code.
CRIU use case [2] was mentioned by Andrei and Danylo:
> Use cases for migrating sparse VMAs are binaries sanitized with ASAN,
> MSAN or TSAN [3]. All of these sanitizers produce sparse mappings of
> shadow memory [4]. Being able to migrate such binaries allows to highly
> reduce the amount of work needed to identify and fix post-migration
> crashes, which happen constantly.
Andrei defines the following uses of this code:
* it is more granular and allows us to track changed pages more
effectively. The current interface can clear dirty bits for the entire
process only. In addition, reading info about pages is a separate
operation. It means we must freeze the process to read information
about all its pages, reset dirty bits, only then we can start dumping
pages. The information about pages becomes more and more outdated,
while we are processing pages. The new interface solves both these
downsides. First, it allows us to read pte bits and clear the
soft-dirty bit atomically. It means that CRIU will not need to freeze
processes to pre-dump their memory. Second, it clears soft-dirty bits
for a specified region of memory. It means CRIU will have actual info
about pages to the moment of dumping them.
* The new interface has to be much faster because basic page filtering
is happening in the kernel. With the old interface, we have to read
pagemap for each page.
*Implementation Evolution (Short Summary)*
From the definition of GetWriteWatch(), we feel like kernel's soft-dirty
feature can be used under the hood with some additions like:
* reset soft-dirty flag for only a specific region of memory instead of
clearing the flag for the entire process
* get and clear soft-dirty flag for a specific region atomically
So we decided to use ioctl on pagemap file to read or/and reset soft-dirty
flag. But using soft-dirty flag, sometimes we get extra pages which weren't
even written. They had become soft-dirty because of VMA merging and
VM_SOFTDIRTY flag. This breaks the definition of GetWriteWatch(). We were
able to by-pass this short coming by ignoring VM_SOFTDIRTY until David
reported that mprotect etc messes up the soft-dirty flag while ignoring
VM_SOFTDIRTY [5]. This wasn't happening until [6] got introduced. We
discussed if we can revert these patches. But we could not reach to any
conclusion. So at this point, I made couple of tries to solve this whole
VM_SOFTDIRTY issue by correcting the soft-dirty implementation:
* [7] Correct the bug fixed wrongly back in 2014. It had potential to cause
regression. We left it behind.
* [8] Keep a list of soft-dirty part of a VMA across splits and merges. I
got the reply don't increase the size of the VMA by 8 bytes.
At this point, we left soft-dirty considering it is too much delicate and
userfaultfd [9] seemed like the only way forward. From there onward, we
have been basing soft-dirty emulation on userfaultfd wp feature where
kernel resolves the faults itself when WP_ASYNC feature is used. It was
straight forward to add WP_ASYNC feature in userfautlfd. Now we get only
those pages dirty or written-to which are really written in reality. (PS
There is another WP_UNPOPULATED userfautfd feature is required which is
needed to avoid pre-faulting memory before write-protecting [9].)
All the different masks were added on the request of CRIU devs to create
interface more generic and better.
[1] https://learn.microsoft.com/en-us/windows/win32/api/memoryapi/nf-memoryapi-getwritewatch
[2] https://lore.kernel.org/all/20221014134802.1361436-1-mdanylo@google.com
[3] https://github.com/google/sanitizers
[4] https://github.com/google/sanitizers/wiki/AddressSanitizerAlgorithm#64-bit
[5] https://lore.kernel.org/all/bfcae708-db21-04b4-0bbe-712badd03071@redhat.com
[6] https://lore.kernel.org/all/20220725142048.30450-1-peterx@redhat.com/
[7] https://lore.kernel.org/all/20221122115007.2787017-1-usama.anjum@collabora.com
[8] https://lore.kernel.org/all/20221220162606.1595355-1-usama.anjum@collabora.com
[9] https://lore.kernel.org/all/20230306213925.617814-1-peterx@redhat.com
[10] https://lore.kernel.org/all/20230125144529.1630917-1-mdanylo@google.com
This patch (of 6):
Add a new userfaultfd-wp feature UFFD_FEATURE_WP_ASYNC, that allows
userfaultfd wr-protect faults to be resolved by the kernel directly.
It can be used like a high accuracy version of soft-dirty, without vma
modifications during tracking, and also with ranged support by default
rather than for a whole mm when reset the protections due to existence of
ioctl(UFFDIO_WRITEPROTECT).
Several goals of such a dirty tracking interface:
1. All types of memory should be supported and tracable. This is nature
for soft-dirty but should mention when the context is userfaultfd,
because it used to only support anon/shmem/hugetlb. The problem is for
a dirty tracking purpose these three types may not be enough, and it's
legal to track anything e.g. any page cache writes from mmap.
2. Protections can be applied to partial of a memory range, without vma
split/merge fuss. The hope is that the tracking itself should not
affect any vma layout change. It also helps when reset happens because
the reset will not need mmap write lock which can block the tracee.
3. Accuracy needs to be maintained. This means we need pte markers to work
on any type of VMA.
One could question that, the whole concept of async dirty tracking is not
really close to fundamentally what userfaultfd used to be: it's not "a
fault to be serviced by userspace" anymore. However, using userfaultfd-wp
here as a framework is convenient for us in at least:
1. VM_UFFD_WP vma flag, which has a very good name to suite something like
this, so we don't need VM_YET_ANOTHER_SOFT_DIRTY. Just use a new
feature bit to identify from a sync version of uffd-wp registration.
2. PTE markers logic can be leveraged across the whole kernel to maintain
the uffd-wp bit as long as an arch supports, this also applies to this
case where uffd-wp bit will be a hint to dirty information and it will
not go lost easily (e.g. when some page cache ptes got zapped).
3. Reuse ioctl(UFFDIO_WRITEPROTECT) interface for either starting or
resetting a range of memory, while there's no counterpart in the old
soft-dirty world, hence if this is wanted in a new design we'll need a
new interface otherwise.
We can somehow understand that commonality because uffd-wp was
fundamentally a similar idea of write-protecting pages just like
soft-dirty.
This implementation allows WP_ASYNC to imply WP_UNPOPULATED, because so
far WP_ASYNC seems to not usable if without WP_UNPOPULATE. This also
gives us chance to modify impl of WP_ASYNC just in case it could be not
depending on WP_UNPOPULATED anymore in the future kernels. It's also fine
to imply that because both features will rely on PTE_MARKER_UFFD_WP config
option, so they'll show up together (or both missing) in an UFFDIO_API
probe.
vma_can_userfault() now allows any VMA if the userfaultfd registration is
only about async uffd-wp. So we can track dirty for all kinds of memory
including generic file systems (like XFS, EXT4 or BTRFS).
One trick worth mention in do_wp_page() is that we need to manually update
vmf->orig_pte here because it can be used later with a pte_same() check -
this path always has FAULT_FLAG_ORIG_PTE_VALID set in the flags.
The major defect of this approach of dirty tracking is we need to populate
the pgtables when tracking starts. Soft-dirty doesn't do it like that.
It's unwanted in the case where the range of memory to track is huge and
unpopulated (e.g., tracking updates on a 10G file with mmap() on top,
without having any page cache installed yet). One way to improve this is
to allow pte markers exist for larger than PTE level for PMD+. That will
not change the interface if to implemented, so we can leave that for
later.
Link: https://lkml.kernel.org/r/20230821141518.870589-1-usama.anjum@collabora.com
Link: https://lkml.kernel.org/r/20230821141518.870589-2-usama.anjum@collabora.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Co-developed-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Signed-off-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Cc: Alex Sierra <alex.sierra@amd.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andrei Vagin <avagin@gmail.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Gustavo A. R. Silva <gustavoars@kernel.org>
Cc: "Liam R. Howlett" <Liam.Howlett@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michal Miroslaw <emmir@google.com>
Cc: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: Nadav Amit <namit@vmware.com>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Paul Gofman <pgofman@codeweavers.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Yun Zhou <yun.zhou@windriver.com>
Cc: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The previous patch added accounting and a limit for the number of
dynamically learned FDB entries per bridge. However it did not provide
means to actually configure those bounds or read back the count. This
patch does that.
Two new netlink attributes are added for the accounting and limit of
dynamically learned FDB entries:
- IFLA_BR_FDB_N_LEARNED (RO) for the number of entries accounted for
a single bridge.
- IFLA_BR_FDB_MAX_LEARNED (RW) for the configured limit of entries for
the bridge.
The new attributes are used like this:
# ip link add name br up type bridge fdb_max_learned 256
# ip link add name v1 up master br type veth peer v2
# ip link set up dev v2
# mausezahn -a rand -c 1024 v2
0.01 seconds (90877 packets per second
# bridge fdb | grep -v permanent | wc -l
256
# ip -d link show dev br
13: br: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 [...]
[...] fdb_n_learned 256 fdb_max_learned 256
Signed-off-by: Johannes Nixdorf <jnixdorf-oss@avm.de>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://lore.kernel.org/r/20231016-fdb_limit-v5-3-32cddff87758@avm.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
