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Revision tags: v6.6.67, v6.6.66, v6.6.65, v6.6.64, v6.6.63, v6.6.62, v6.6.61, v6.6.60, v6.6.59, v6.6.58, v6.6.57, v6.6.56, v6.6.55, v6.6.54, v6.6.53, v6.6.52, v6.6.51, v6.6.50, v6.6.49, v6.6.48, v6.6.47, v6.6.46, v6.6.45, v6.6.44, v6.6.43, v6.6.42, v6.6.41, v6.6.40, v6.6.39, v6.6.38, v6.6.37, v6.6.36, v6.6.35, v6.6.34, v6.6.33, v6.6.32, v6.6.31, v6.6.30, v6.6.29, v6.6.28, v6.6.27, v6.6.26, v6.6.25, v6.6.24, v6.6.23, v6.6.16, v6.6.15, v6.6.14, v6.6.13, v6.6.12, v6.6.11, v6.6.10, v6.6.9, v6.6.8, v6.6.7, v6.6.6, v6.6.5, v6.6.4, v6.6.3, v6.6.2, v6.5.11, v6.6.1, v6.5.10, v6.6, v6.5.9, v6.5.8, v6.5.7, v6.5.6, v6.5.5, v6.5.4, v6.5.3, v6.5.2, v6.1.51, v6.5.1
# 1ac731c5 30-Aug-2023 Dmitry Torokhov <dmitry.torokhov@gmail.com>

Merge branch 'next' into for-linus

Prepare input updates for 6.6 merge window.


Revision tags: v6.1.50, v6.5, v6.1.49, v6.1.48, v6.1.46, v6.1.45, v6.1.44, v6.1.43, v6.1.42, v6.1.41, v6.1.40, v6.1.39
# 50501936 17-Jul-2023 Dmitry Torokhov <dmitry.torokhov@gmail.com>

Merge tag 'v6.4' into next

Sync up with mainline to bring in updates to shared infrastructure.


Revision tags: v6.1.38, v6.1.37, v6.1.36, v6.4, v6.1.35
# db6da59c 15-Jun-2023 Thomas Zimmermann <tzimmermann@suse.de>

Merge drm/drm-next into drm-misc-next-fixes

Backmerging to sync drm-misc-next-fixes with drm-misc-next.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>


Revision tags: v6.1.34
# 03c60192 12-Jun-2023 Dmitry Baryshkov <dmitry.baryshkov@linaro.org>

Merge branch 'drm-next' of git://anongit.freedesktop.org/drm/drm into msm-next-lumag-base

Merge the drm-next tree to pick up the DRM DSC helpers (merged via
drm-intel-next tree). MSM DSC v1.2 patche

Merge branch 'drm-next' of git://anongit.freedesktop.org/drm/drm into msm-next-lumag-base

Merge the drm-next tree to pick up the DRM DSC helpers (merged via
drm-intel-next tree). MSM DSC v1.2 patches depend on these helpers.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>

show more ...


Revision tags: v6.1.33
# 5c680050 06-Jun-2023 Miquel Raynal <miquel.raynal@bootlin.com>

Merge tag 'v6.4-rc4' into wpan-next/staging

Linux 6.4-rc4


# 9ff17e6b 05-Jun-2023 Tvrtko Ursulin <tvrtko.ursulin@intel.com>

Merge drm/drm-next into drm-intel-gt-next

For conflict avoidance we need the following commit:

c9a9f18d3ad8 drm/i915/huc: use const struct bus_type pointers

Signed-off-by: Tvrtko Ursulin <tvrtko

Merge drm/drm-next into drm-intel-gt-next

For conflict avoidance we need the following commit:

c9a9f18d3ad8 drm/i915/huc: use const struct bus_type pointers

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

show more ...


Revision tags: v6.1.32, v6.1.31, v6.1.30
# 9c3a985f 17-May-2023 Rodrigo Vivi <rodrigo.vivi@intel.com>

Merge drm/drm-next into drm-intel-next

Backmerge to get some hwmon dependencies.

Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>


Revision tags: v6.1.29
# 50282fd5 12-May-2023 Maxime Ripard <maxime@cerno.tech>

Merge drm/drm-fixes into drm-misc-fixes

Let's bring 6.4-rc1 in drm-misc-fixes to start the new fix cycle.

Signed-off-by: Maxime Ripard <maxime@cerno.tech>


Revision tags: v6.1.28
# ff32fcca 09-May-2023 Maxime Ripard <maxime@cerno.tech>

Merge drm/drm-next into drm-misc-next

Start the 6.5 release cycle.

Signed-off-by: Maxime Ripard <maxime@cerno.tech>


# 9a87ffc9 01-May-2023 Dmitry Torokhov <dmitry.torokhov@gmail.com>

Merge branch 'next' into for-linus

Prepare input updates for 6.4 merge window.


Revision tags: v6.1.27
# 6e98b09d 26-Apr-2023 Linus Torvalds <torvalds@linux-foundation.org>

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

Pull networking updates from Paolo Abeni:
"Core:

- Introduce a config option to tweak MAX_SKB_FRAGS. In

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

Pull networking updates from Paolo Abeni:
"Core:

- Introduce a config option to tweak MAX_SKB_FRAGS. Increasing the
default value allows for better BIG TCP performances

- Reduce compound page head access for zero-copy data transfers

- RPS/RFS improvements, avoiding unneeded NET_RX_SOFTIRQ when
possible

- Threaded NAPI improvements, adding defer skb free support and
unneeded softirq avoidance

- Address dst_entry reference count scalability issues, via false
sharing avoidance and optimize refcount tracking

- Add lockless accesses annotation to sk_err[_soft]

- Optimize again the skb struct layout

- Extends the skb drop reasons to make it usable by multiple
subsystems

- Better const qualifier awareness for socket casts

BPF:

- Add skb and XDP typed dynptrs which allow BPF programs for more
ergonomic and less brittle iteration through data and
variable-sized accesses

- Add a new BPF netfilter program type and minimal support to hook
BPF programs to netfilter hooks such as prerouting or forward

- Add more precise memory usage reporting for all BPF map types

- Adds support for using {FOU,GUE} encap with an ipip device
operating in collect_md mode and add a set of BPF kfuncs for
controlling encap params

- Allow BPF programs to detect at load time whether a particular
kfunc exists or not, and also add support for this in light
skeleton

- Bigger batch of BPF verifier improvements to prepare for upcoming
BPF open-coded iterators allowing for less restrictive looping
capabilities

- Rework RCU enforcement in the verifier, add kptr_rcu and enforce
BPF programs to NULL-check before passing such pointers into kfunc

- Add support for kptrs in percpu hashmaps, percpu LRU hashmaps and
in local storage maps

- Enable RCU semantics for task BPF kptrs and allow referenced kptr
tasks to be stored in BPF maps

- Add support for refcounted local kptrs to the verifier for allowing
shared ownership, useful for adding a node to both the BPF list and
rbtree

- Add BPF verifier support for ST instructions in
convert_ctx_access() which will help new -mcpu=v4 clang flag to
start emitting them

- Add ARM32 USDT support to libbpf

- Improve bpftool's visual program dump which produces the control
flow graph in a DOT format by adding C source inline annotations

Protocols:

- IPv4: Allow adding to IPv4 address a 'protocol' tag. Such value
indicates the provenance of the IP address

- IPv6: optimize route lookup, dropping unneeded R/W lock acquisition

- Add the handshake upcall mechanism, allowing the user-space to
implement generic TLS handshake on kernel's behalf

- Bridge: support per-{Port, VLAN} neighbor suppression, increasing
resilience to nodes failures

- SCTP: add support for Fair Capacity and Weighted Fair Queueing
schedulers

- MPTCP: delay first subflow allocation up to its first usage. This
will allow for later better LSM interaction

- xfrm: Remove inner/outer modes from input/output path. These are
not needed anymore

- WiFi:
- reduced neighbor report (RNR) handling for AP mode
- HW timestamping support
- support for randomized auth/deauth TA for PASN privacy
- per-link debugfs for multi-link
- TC offload support for mac80211 drivers
- mac80211 mesh fast-xmit and fast-rx support
- enable Wi-Fi 7 (EHT) mesh support

Netfilter:

- Add nf_tables 'brouting' support, to force a packet to be routed
instead of being bridged

- Update bridge netfilter and ovs conntrack helpers to handle IPv6
Jumbo packets properly, i.e. fetch the packet length from
hop-by-hop extension header. This is needed for BIT TCP support

- The iptables 32bit compat interface isn't compiled in by default
anymore

- Move ip(6)tables builtin icmp matches to the udptcp one. This has
the advantage that icmp/icmpv6 match doesn't load the
iptables/ip6tables modules anymore when iptables-nft is used

- Extended netlink error report for netdevice in flowtables and
netdev/chains. Allow for incrementally add/delete devices to netdev
basechain. Allow to create netdev chain without device

Driver API:

- Remove redundant Device Control Error Reporting Enable, as PCI core
has already error reporting enabled at enumeration time

- Move Multicast DB netlink handlers to core, allowing devices other
then bridge to use them

- Allow the page_pool to directly recycle the pages from safely
localized NAPI

- Implement lockless TX queue stop/wake combo macros, allowing for
further code de-duplication and sanitization

- Add YNL support for user headers and struct attrs

- Add partial YNL specification for devlink

- Add partial YNL specification for ethtool

- Add tc-mqprio and tc-taprio support for preemptible traffic classes

- Add tx push buf len param to ethtool, specifies the maximum number
of bytes of a transmitted packet a driver can push directly to the
underlying device

- Add basic LED support for switch/phy

- Add NAPI documentation, stop relaying on external links

- Convert dsa_master_ioctl() to netdev notifier. This is a
preparatory work to make the hardware timestamping layer selectable
by user space

- Add transceiver support and improve the error messages for CAN-FD
controllers

New hardware / drivers:

- Ethernet:
- AMD/Pensando core device support
- MediaTek MT7981 SoC
- MediaTek MT7988 SoC
- Broadcom BCM53134 embedded switch
- Texas Instruments CPSW9G ethernet switch
- Qualcomm EMAC3 DWMAC ethernet
- StarFive JH7110 SoC
- NXP CBTX ethernet PHY

- WiFi:
- Apple M1 Pro/Max devices
- RealTek rtl8710bu/rtl8188gu
- RealTek rtl8822bs, rtl8822cs and rtl8821cs SDIO chipset

- Bluetooth:
- Realtek RTL8821CS, RTL8851B, RTL8852BS
- Mediatek MT7663, MT7922
- NXP w8997
- Actions Semi ATS2851
- QTI WCN6855
- Marvell 88W8997

- Can:
- STMicroelectronics bxcan stm32f429

Drivers:

- Ethernet NICs:
- Intel (1G, icg):
- add tracking and reporting of QBV config errors
- add support for configuring max SDU for each Tx queue
- Intel (100G, ice):
- refactor mailbox overflow detection to support Scalable IOV
- GNSS interface optimization
- Intel (i40e):
- support XDP multi-buffer
- nVidia/Mellanox:
- add the support for linux bridge multicast offload
- enable TC offload for egress and engress MACVLAN over bond
- add support for VxLAN GBP encap/decap flows offload
- extend packet offload to fully support libreswan
- support tunnel mode in mlx5 IPsec packet offload
- extend XDP multi-buffer support
- support MACsec VLAN offload
- add support for dynamic msix vectors allocation
- drop RX page_cache and fully use page_pool
- implement thermal zone to report NIC temperature
- Netronome/Corigine:
- add support for multi-zone conntrack offload
- Solarflare/Xilinx:
- support offloading TC VLAN push/pop actions to the MAE
- support TC decap rules
- support unicast PTP

- Other NICs:
- Broadcom (bnxt): enforce software based freq adjustments only on
shared PHC NIC
- RealTek (r8169): refactor to addess ASPM issues during NAPI poll
- Micrel (lan8841): add support for PTP_PF_PEROUT
- Cadence (macb): enable PTP unicast
- Engleder (tsnep): add XDP socket zero-copy support
- virtio-net: implement exact header length guest feature
- veth: add page_pool support for page recycling
- vxlan: add MDB data path support
- gve: add XDP support for GQI-QPL format
- geneve: accept every ethertype
- macvlan: allow some packets to bypass broadcast queue
- mana: add support for jumbo frame

- Ethernet high-speed switches:
- Microchip (sparx5): Add support for TC flower templates

- Ethernet embedded switches:
- Broadcom (b54):
- configure 6318 and 63268 RGMII ports
- Marvell (mv88e6xxx):
- faster C45 bus scan
- Microchip:
- lan966x:
- add support for IS1 VCAP
- better TX/RX from/to CPU performances
- ksz9477: add ETS Qdisc support
- ksz8: enhance static MAC table operations and error handling
- sama7g5: add PTP capability
- NXP (ocelot):
- add support for external ports
- add support for preemptible traffic classes
- Texas Instruments:
- add CPSWxG SGMII support for J7200 and J721E

- Intel WiFi (iwlwifi):
- preparation for Wi-Fi 7 EHT and multi-link support
- EHT (Wi-Fi 7) sniffer support
- hardware timestamping support for some devices/firwmares
- TX beacon protection on newer hardware

- Qualcomm 802.11ax WiFi (ath11k):
- MU-MIMO parameters support
- ack signal support for management packets

- RealTek WiFi (rtw88):
- SDIO bus support
- better support for some SDIO devices (e.g. MAC address from
efuse)

- RealTek WiFi (rtw89):
- HW scan support for 8852b
- better support for 6 GHz scanning
- support for various newer firmware APIs
- framework firmware backwards compatibility

- MediaTek WiFi (mt76):
- P2P support
- mesh A-MSDU support
- EHT (Wi-Fi 7) support
- coredump support"

* tag 'net-next-6.4' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2078 commits)
net: phy: hide the PHYLIB_LEDS knob
net: phy: marvell-88x2222: remove unnecessary (void*) conversions
tcp/udp: Fix memleaks of sk and zerocopy skbs with TX timestamp.
net: amd: Fix link leak when verifying config failed
net: phy: marvell: Fix inconsistent indenting in led_blink_set
lan966x: Don't use xdp_frame when action is XDP_TX
tsnep: Add XDP socket zero-copy TX support
tsnep: Add XDP socket zero-copy RX support
tsnep: Move skb receive action to separate function
tsnep: Add functions for queue enable/disable
tsnep: Rework TX/RX queue initialization
tsnep: Replace modulo operation with mask
net: phy: dp83867: Add led_brightness_set support
net: phy: Fix reading LED reg property
drivers: nfc: nfcsim: remove return value check of `dev_dir`
net: phy: dp83867: Remove unnecessary (void*) conversions
net: ethtool: coalesce: try to make user settings stick twice
net: mana: Check if netdev/napi_alloc_frag returns single page
net: mana: Rename mana_refill_rxoob and remove some empty lines
net: veth: add page_pool stats
...

show more ...


Revision tags: v6.1.26, v6.3, v6.1.25
# c2865b11 13-Apr-2023 Jakub Kicinski <kuba@kernel.org>

Daniel Borkmann says:

====================
pull-request: bpf-next 2023-04-13

We've added 260 non-merge commits during the last 36 day(s) which contain
a total of 356 files changed, 21786 insertions

Daniel Borkmann says:

====================
pull-request: bpf-next 2023-04-13

We've added 260 non-merge commits during the last 36 day(s) which contain
a total of 356 files changed, 21786 insertions(+), 11275 deletions(-).

The main changes are:

1) Rework BPF verifier log behavior and implement it as a rotating log
by default with the option to retain old-style fixed log behavior,
from Andrii Nakryiko.

2) Adds support for using {FOU,GUE} encap with an ipip device operating
in collect_md mode and add a set of BPF kfuncs for controlling encap
params, from Christian Ehrig.

3) Allow BPF programs to detect at load time whether a particular kfunc
exists or not, and also add support for this in light skeleton,
from Alexei Starovoitov.

4) Optimize hashmap lookups when key size is multiple of 4,
from Anton Protopopov.

5) Enable RCU semantics for task BPF kptrs and allow referenced kptr
tasks to be stored in BPF maps, from David Vernet.

6) Add support for stashing local BPF kptr into a map value via
bpf_kptr_xchg(). This is useful e.g. for rbtree node creation
for new cgroups, from Dave Marchevsky.

7) Fix BTF handling of is_int_ptr to skip modifiers to work around
tracing issues where a program cannot be attached, from Feng Zhou.

8) Migrate a big portion of test_verifier unit tests over to
test_progs -a verifier_* via inline asm to ease {read,debug}ability,
from Eduard Zingerman.

9) Several updates to the instruction-set.rst documentation
which is subject to future IETF standardization
(https://lwn.net/Articles/926882/), from Dave Thaler.

10) Fix BPF verifier in the __reg_bound_offset's 64->32 tnum sub-register
known bits information propagation, from Daniel Borkmann.

11) Add skb bitfield compaction work related to BPF with the overall goal
to make more of the sk_buff bits optional, from Jakub Kicinski.

12) BPF selftest cleanups for build id extraction which stand on its own
from the upcoming integration work of build id into struct file object,
from Jiri Olsa.

13) Add fixes and optimizations for xsk descriptor validation and several
selftest improvements for xsk sockets, from Kal Conley.

14) Add BPF links for struct_ops and enable switching implementations
of BPF TCP cong-ctls under a given name by replacing backing
struct_ops map, from Kui-Feng Lee.

15) Remove a misleading BPF verifier env->bypass_spec_v1 check on variable
offset stack read as earlier Spectre checks cover this,
from Luis Gerhorst.

16) Fix issues in copy_from_user_nofault() for BPF and other tracers
to resemble copy_from_user_nmi() from safety PoV, from Florian Lehner
and Alexei Starovoitov.

17) Add --json-summary option to test_progs in order for CI tooling to
ease parsing of test results, from Manu Bretelle.

18) Batch of improvements and refactoring to prep for upcoming
bpf_local_storage conversion to bpf_mem_cache_{alloc,free} allocator,
from Martin KaFai Lau.

19) Improve bpftool's visual program dump which produces the control
flow graph in a DOT format by adding C source inline annotations,
from Quentin Monnet.

20) Fix attaching fentry/fexit/fmod_ret/lsm to modules by extracting
the module name from BTF of the target and searching kallsyms of
the correct module, from Viktor Malik.

21) Improve BPF verifier handling of '<const> <cond> <non_const>'
to better detect whether in particular jmp32 branches are taken,
from Yonghong Song.

22) Allow BPF TCP cong-ctls to write app_limited of struct tcp_sock.
A built-in cc or one from a kernel module is already able to write
to app_limited, from Yixin Shen.

Conflicts:

Documentation/bpf/bpf_devel_QA.rst
b7abcd9c656b ("bpf, doc: Link to submitting-patches.rst for general patch submission info")
0f10f647f455 ("bpf, docs: Use internal linking for link to netdev subsystem doc")
https://lore.kernel.org/all/20230307095812.236eb1be@canb.auug.org.au/

include/net/ip_tunnels.h
bc9d003dc48c3 ("ip_tunnel: Preserve pointer const in ip_tunnel_info_opts")
ac931d4cdec3d ("ipip,ip_tunnel,sit: Add FOU support for externally controlled ipip devices")
https://lore.kernel.org/all/20230413161235.4093777-1-broonie@kernel.org/

net/bpf/test_run.c
e5995bc7e2ba ("bpf, test_run: fix crashes due to XDP frame overwriting/corruption")
294635a8165a ("bpf, test_run: fix &xdp_frame misplacement for LIVE_FRAMES")
https://lore.kernel.org/all/20230320102619.05b80a98@canb.auug.org.au/
====================

Link: https://lore.kernel.org/r/20230413191525.7295-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

show more ...


Revision tags: v6.1.24
# ea68a3e9 11-Apr-2023 Joonas Lahtinen <joonas.lahtinen@linux.intel.com>

Merge drm/drm-next into drm-intel-gt-next

Need to pull in commit from drm-next (earlier in drm-intel-next):

1eca0778f4b3 ("drm/i915: add struct i915_dsm to wrap dsm members together")

In order to

Merge drm/drm-next into drm-intel-gt-next

Need to pull in commit from drm-next (earlier in drm-intel-next):

1eca0778f4b3 ("drm/i915: add struct i915_dsm to wrap dsm members together")

In order to merge following patch to drm-intel-gt-next:

https://patchwork.freedesktop.org/patch/530942/?series=114925&rev=6

Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>

show more ...


Revision tags: v6.1.23
# a033907e 01-Apr-2023 Alexei Starovoitov <ast@kernel.org>

Merge branch 'Enable RCU semantics for task kptrs'

David Vernet says:

====================

In commit 22df776a9a86 ("tasks: Extract rcu_users out of union"), the
'refcount_t rcu_users' field was ex

Merge branch 'Enable RCU semantics for task kptrs'

David Vernet says:

====================

In commit 22df776a9a86 ("tasks: Extract rcu_users out of union"), the
'refcount_t rcu_users' field was extracted out of a union with the
'struct rcu_head rcu' field. This allows us to use the field for
refcounting struct task_struct with RCU protection, as the RCU callback
no longer flips rcu_users to be nonzero after the callback is scheduled.

This patch set leverages this to do a few things:

1. Marks struct task_struct as RCU safe in the verifier, allowing
referenced kptr tasks stored in maps to be accessed in an RCU
read region without acquiring a reference (with just a NULL check).
2. Makes bpf_task_acquire() a KF_ACQUIRE | KF_RCU | KF_RET_NULL kfunc.
3. Removes bpf_task_kptr_get() and bpf_task_acquire_not_zero(), as
they're now redundant with the above two changes.
4. Updates selftests and documentation accordingly.
---
Changelog:
v1: https://lore.kernel.org/all/20230331005733.406202-1-void@manifault.com/
v1 -> v2:
- Remove testcases validating nested trust inheritance. The first
version used 'struct task_struct __rcu *parent', but because that
field has the __rcu tag it functions differently on gcc and llvm and
causes gcc selftests to fail. Alexei is reworking nested trust,
anyways so let's leave it off for now (Alexei).
====================

Signed-off-by: Alexei Starovoitov <ast@kernel.org>

show more ...


# f85671c6 31-Mar-2023 David Vernet <void@manifault.com>

bpf: Remove now-defunct task kfuncs

In commit 22df776a9a86 ("tasks: Extract rcu_users out of union"), the
'refcount_t rcu_users' field was extracted out of a union with the
'struct rcu_head rcu' fie

bpf: Remove now-defunct task kfuncs

In commit 22df776a9a86 ("tasks: Extract rcu_users out of union"), the
'refcount_t rcu_users' field was extracted out of a union with the
'struct rcu_head rcu' field. This allows us to safely perform a
refcount_inc_not_zero() on task->rcu_users when acquiring a reference on
a task struct. A prior patch leveraged this by making struct task_struct
an RCU-protected object in the verifier, and by bpf_task_acquire() to
use the task->rcu_users field for synchronization.

Now that we can use RCU to protect tasks, we no longer need
bpf_task_kptr_get(), or bpf_task_acquire_not_zero(). bpf_task_kptr_get()
is truly completely unnecessary, as we can just use RCU to get the
object. bpf_task_acquire_not_zero() is now equivalent to
bpf_task_acquire().

In addition to these changes, this patch also updates the associated
selftests to no longer use these kfuncs.

Signed-off-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20230331195733.699708-3-void@manifault.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

show more ...


# d02c48fa 31-Mar-2023 David Vernet <void@manifault.com>

bpf: Make struct task_struct an RCU-safe type

struct task_struct objects are a bit interesting in terms of how their
lifetime is protected by refcounts. task structs have two refcount
fields:

1. re

bpf: Make struct task_struct an RCU-safe type

struct task_struct objects are a bit interesting in terms of how their
lifetime is protected by refcounts. task structs have two refcount
fields:

1. refcount_t usage: Protects the memory backing the task struct. When
this refcount drops to 0, the task is immediately freed, without
waiting for an RCU grace period to elapse. This is the field that
most callers in the kernel currently use to ensure that a task
remains valid while it's being referenced, and is what's currently
tracked with bpf_task_acquire() and bpf_task_release().

2. refcount_t rcu_users: A refcount field which, when it drops to 0,
schedules an RCU callback that drops a reference held on the 'usage'
field above (which is acquired when the task is first created). This
field therefore provides a form of RCU protection on the task by
ensuring that at least one 'usage' refcount will be held until an RCU
grace period has elapsed. The qualifier "a form of" is important
here, as a task can remain valid after task->rcu_users has dropped to
0 and the subsequent RCU gp has elapsed.

In terms of BPF, we want to use task->rcu_users to protect tasks that
function as referenced kptrs, and to allow tasks stored as referenced
kptrs in maps to be accessed with RCU protection.

Let's first determine whether we can safely use task->rcu_users to
protect tasks stored in maps. All of the bpf_task* kfuncs can only be
called from tracepoint, struct_ops, or BPF_PROG_TYPE_SCHED_CLS, program
types. For tracepoint and struct_ops programs, the struct task_struct
passed to a program handler will always be trusted, so it will always be
safe to call bpf_task_acquire() with any task passed to a program.
Note, however, that we must update bpf_task_acquire() to be KF_RET_NULL,
as it is possible that the task has exited by the time the program is
invoked, even if the pointer is still currently valid because the main
kernel holds a task->usage refcount. For BPF_PROG_TYPE_SCHED_CLS, tasks
should never be passed as an argument to the any program handlers, so it
should not be relevant.

The second question is whether it's safe to use RCU to access a task
that was acquired with bpf_task_acquire(), and stored in a map. Because
bpf_task_acquire() now uses task->rcu_users, it follows that if the task
is present in the map, that it must have had at least one
task->rcu_users refcount by the time the current RCU cs was started.
Therefore, it's safe to access that task until the end of the current
RCU cs.

With all that said, this patch makes struct task_struct is an
RCU-protected object. In doing so, we also change bpf_task_acquire() to
be KF_ACQUIRE | KF_RCU | KF_RET_NULL, and adjust any selftests as
necessary. A subsequent patch will remove bpf_task_kptr_get(), and
bpf_task_acquire_not_zero() respectively.

Signed-off-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20230331195733.699708-2-void@manifault.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

show more ...


Revision tags: v6.1.22
# cecdd52a 28-Mar-2023 Rodrigo Vivi <rodrigo.vivi@intel.com>

Merge drm/drm-next into drm-intel-next

Catch up with 6.3-rc cycle...

Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>


# 496f4f1b 25-Mar-2023 Alexei Starovoitov <ast@kernel.org>

Merge branch 'Don't invoke KPTR_REF destructor on NULL xchg'

David Vernet says:

====================

When a map value is being freed, we loop over all of the fields of the
corresponding BPF object

Merge branch 'Don't invoke KPTR_REF destructor on NULL xchg'

David Vernet says:

====================

When a map value is being freed, we loop over all of the fields of the
corresponding BPF object and issue the appropriate cleanup calls
corresponding to the field's type. If the field is a referenced kptr, we
atomically xchg the value out of the map, and invoke the kptr's
destructor on whatever was there before.

Currently, we always invoke the destructor (or bpf_obj_drop() for a
local kptr) on any kptr, including if no value was xchg'd out of the
map. This means that any function serving as the kptr's KF_RELEASE
destructor must always treat the argument as possibly NULL, and we
invoke unnecessary (and seemingly unsafe) cleanup logic for the local
kptr path as well.

This is an odd requirement -- KF_RELEASE kfuncs that are invoked by BPF
programs do not have this restriction, and the verifier will fail to
load the program if the register containing the to-be-released type has
any untrusted modifiers (e.g. PTR_UNTRUSTED or PTR_MAYBE_NULL). So as to
simplify the expectations required for a KF_RELEASE kfunc, this patch
set updates the KPTR_REF destructor logic to only be invoked when a
non-NULL value is xchg'd out of the map.

Additionally, the patch removes now-unnecessary KF_RELEASE calls from
several kfuncs, and finally, updates the verifier to have KF_RELEASE
automatically imply KF_TRUSTED_ARGS. This restriction was already
implicitly happening because of the aforementioned logic in the verifier
to reject any regs with untrusted modifiers, and to enforce that
KF_RELEASE args are passed with a 0 offset. This change just updates the
behavior to match that of other trusted args. This patch is left to the
end of the series in case it happens to be controversial, as it arguably
is slightly orthogonal to the purpose of the rest of the series.
====================

Signed-off-by: Alexei Starovoitov <ast@kernel.org>

show more ...


# 6c831c46 25-Mar-2023 David Vernet <void@manifault.com>

bpf: Treat KF_RELEASE kfuncs as KF_TRUSTED_ARGS

KF_RELEASE kfuncs are not currently treated as having KF_TRUSTED_ARGS,
even though they have a superset of the requirements of KF_TRUSTED_ARGS.
Like K

bpf: Treat KF_RELEASE kfuncs as KF_TRUSTED_ARGS

KF_RELEASE kfuncs are not currently treated as having KF_TRUSTED_ARGS,
even though they have a superset of the requirements of KF_TRUSTED_ARGS.
Like KF_TRUSTED_ARGS, KF_RELEASE kfuncs require a 0-offset argument, and
don't allow NULL-able arguments. Unlike KF_TRUSTED_ARGS which require
_either_ an argument with ref_obj_id > 0, _or_ (ref->type &
BPF_REG_TRUSTED_MODIFIERS) (and no unsafe modifiers allowed), KF_RELEASE
only allows for ref_obj_id > 0. Because KF_RELEASE today doesn't
automatically imply KF_TRUSTED_ARGS, some of these requirements are
enforced in different ways that can make the behavior of the verifier
feel unpredictable. For example, a KF_RELEASE kfunc with a NULL-able
argument will currently fail in the verifier with a message like, "arg#0
is ptr_or_null_ expected ptr_ or socket" rather than "Possibly NULL
pointer passed to trusted arg0". Our intention is the same, but the
semantics are different due to implemenetation details that kfunc authors
and BPF program writers should not need to care about.

Let's make the behavior of the verifier more consistent and intuitive by
having KF_RELEASE kfuncs imply the presence of KF_TRUSTED_ARGS. Our
eventual goal is to have all kfuncs assume KF_TRUSTED_ARGS by default
anyways, so this takes us a step in that direction.

Note that it does not make sense to assume KF_TRUSTED_ARGS for all
KF_ACQUIRE kfuncs. KF_ACQUIRE kfuncs can have looser semantics than
KF_RELEASE, with e.g. KF_RCU | KF_RET_NULL. We may want to have
KF_ACQUIRE imply KF_TRUSTED_ARGS _unless_ KF_RCU is specified, but that
can be left to another patch set, and there are no such subtleties to
address for KF_RELEASE.

Signed-off-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20230325213144.486885-4-void@manifault.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

show more ...


Revision tags: v6.1.21
# e752ab11 20-Mar-2023 Rob Clark <robdclark@chromium.org>

Merge remote-tracking branch 'drm/drm-next' into msm-next

Merge drm-next into msm-next to pick up external clk and PM dependencies
for improved a6xx GPU reset sequence.

Signed-off-by: Rob Clark <ro

Merge remote-tracking branch 'drm/drm-next' into msm-next

Merge drm-next into msm-next to pick up external clk and PM dependencies
for improved a6xx GPU reset sequence.

Signed-off-by: Rob Clark <robdclark@chromium.org>

show more ...


# d26a3a6c 17-Mar-2023 Dmitry Torokhov <dmitry.torokhov@gmail.com>

Merge tag 'v6.3-rc2' into next

Merge with mainline to get of_property_present() and other newer APIs.


Revision tags: v6.1.20
# 283b40c5 14-Mar-2023 Martin KaFai Lau <martin.lau@kernel.org>

Merge branch 'bpf: Allow helpers access ptr_to_btf_id.'

Alexei Starovoitov says:

====================

From: Alexei Starovoitov <ast@kernel.org>

Allow code like:
bpf_strncmp(task->comm, 16, "foo")

Merge branch 'bpf: Allow helpers access ptr_to_btf_id.'

Alexei Starovoitov says:

====================

From: Alexei Starovoitov <ast@kernel.org>

Allow code like:
bpf_strncmp(task->comm, 16, "foo");
====================

Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>

show more ...


# f25fd608 13-Mar-2023 Alexei Starovoitov <ast@kernel.org>

selftests/bpf: Add various tests to check helper access into ptr_to_btf_id.

Add various tests to check helper access into ptr_to_btf_id.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by:

selftests/bpf: Add various tests to check helper access into ptr_to_btf_id.

Add various tests to check helper access into ptr_to_btf_id.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20230313235845.61029-4-alexei.starovoitov@gmail.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>

show more ...


Revision tags: v6.1.19
# b3c9a041 13-Mar-2023 Thomas Zimmermann <tzimmermann@suse.de>

Merge drm/drm-fixes into drm-misc-fixes

Backmerging to get latest upstream.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>


# a1eccc57 13-Mar-2023 Thomas Zimmermann <tzimmermann@suse.de>

Merge drm/drm-next into drm-misc-next

Backmerging to get v6.3-rc1 and sync with the other DRM trees.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>


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