pr_flush() does not guarantee that all messages would really get flushed
to the console. The best it could do is to wait with a given timeout.[*]
The current interval 100ms for checking the progress might seem too
long in some situations. For example, such delays are not appreciated
during suspend and resume especially when the consoles have been flushed
"long" time before the check.
On the other hand, the sleeping wait might be useful in other situations.
Especially, it would allow flushing the messages using printk kthreads
on the same CPU[*].
Use msleep(1) as a compromise.
Also measure the time using jiffies. msleep() does not guarantee
precise wakeup after the given delay. It might be much longer,
especially for times < 20s. See Documentation/timers/timers-howto.rst
for more details.
Note that msecs_to_jiffies() already translates a negative value into
an infinite timeout.
[*] console_unlock() does not guarantee flushing the consoles since
the commit dbdda842fe ("printk: Add console owner and waiter
logic to load balance console writes").
It would be possible to guarantee it another way. For example,
the spinning might be enabled only when the console_lock has been
taken via console_trylock().
But the load balancing is helpful. And more importantly, the flush
with a timeout has been added as a preparation step for introducing
printk kthreads.
Signed-off-by: Petr Mladek <pmladek@suse.com>
Reviewed-by: John Ogness <john.ogness@linutronix.de>
Link: https://lore.kernel.org/r/20231006082151.6969-3-pmladek@suse.com
Commit 9e70a5e109 ("printk: Add per-console suspended state")
removed console lock usage during resume and replaced it with
the clearly defined console_list_lock and srcu mechanisms.
However, the console lock usage had an important side-effect
of flushing the consoles. After its removal, consoles were no
longer flushed before checking their progress.
Add the console_lock/console_unlock dance to the beginning
of __pr_flush() to actually flush the consoles before checking
their progress. Also add comments to clarify this additional
usage of the console lock.
Note that console_unlock() does not guarantee flushing all messages
since the commit dbdda842fe ("printk: Add console owner and waiter
logic to load balance console writes").
Reported-by: Todd Brandt <todd.e.brandt@intel.com>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=217955
Fixes: 9e70a5e109 ("printk: Add per-console suspended state")
Co-developed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Link: https://lore.kernel.org/r/20231006082151.6969-2-pmladek@suse.com
When CONFIG_PRINTK is not set, PRINTK_MESSAGE_MAX is 0. This
leads to a zero-sized array @outbuf in @printk_shared_pbufs. In
console_flush_all() a pointer to the first element of the array
is assigned with:
char *outbuf = &printk_shared_pbufs.outbuf[0];
For !CONFIG_PRINTK this leads to a compiler warning:
warning: array subscript 0 is outside array bounds of
'char[0]' [-Warray-bounds]
This is not really dangerous because printk_get_next_message()
always returns false for !CONFIG_PRINTK, which leads to @outbuf
never being used. However, it makes no sense to even compile
these functions for !CONFIG_PRINTK.
Extend the existing '#ifdef CONFIG_PRINTK' block to contain
the formatting and emitting functions since these have no
purpose in !CONFIG_PRINTK. This also allows removing several
more !CONFIG_PRINTK dummies as well as moving
@suppress_panic_printk into a CONFIG_PRINTK block.
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202309201724.M9BMAQIh-lkp@intel.com/
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20230920155238.670439-1-john.ogness@linutronix.de
Implement an emit function for nbcon consoles to output printk
messages. It utilizes the lockless printk_get_next_message() and
console_prepend_dropped() functions to retrieve/build the output
message. The emit function includes the required safety points to
check for handover/takeover and calls a new write_atomic callback
of the console driver to output the message. It also includes
proper handling for updating the nbcon console sequence number.
A new nbcon_write_context struct is introduced. This is provided
to the write_atomic callback and includes only the information
necessary for performing atomic writes.
Co-developed-by: John Ogness <john.ogness@linutronix.de>
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Signed-off-by: Thomas Gleixner (Intel) <tglx@linutronix.de>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20230916192007.608398-8-john.ogness@linutronix.de
Add an atomic_long_t field @nbcon_seq to the console struct to
store the sequence number for nbcon consoles. For nbcon consoles
this will be used instead of the non-atomic @seq field. The new
field allows for safe atomic sequence number updates without
requiring any locking.
On 64bit systems the new field stores the full sequence number.
On 32bit systems the new field stores the lower 32 bits of the
sequence number, which are expanded to 64bit as needed by
folding the values based on the sequence numbers available in
the ringbuffer.
For 32bit systems, having a 32bit representation in the console
is sufficient. If a console ever gets more than 2^31 records
behind the ringbuffer then this is the least of the problems.
Co-developed-by: John Ogness <john.ogness@linutronix.de>
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Signed-off-by: Thomas Gleixner (Intel) <tglx@linutronix.de>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20230916192007.608398-7-john.ogness@linutronix.de
Provide functions that are related to the safe handover mechanism
and allow console drivers to dynamically specify unsafe regions:
- nbcon_context_can_proceed()
Invoked by a console owner to check whether a handover request
is pending or whether the console has been taken over by another
context. If a handover request is pending, this function will
also perform the handover, thus cancelling its own ownership.
- nbcon_context_enter_unsafe()/nbcon_context_exit_unsafe()
Invoked by a console owner to denote that the driver is about
to enter or leave a critical region where a take over is unsafe.
The exit variant is the point where the current owner releases
the lock for a higher priority context which asked for the
friendly handover.
The unsafe state is stored in the console state and allows a
new context to make informed decisions whether to attempt a
takeover of such a console. The unsafe state is also available
to the driver so that it can make informed decisions about the
required actions and possibly take a special emergency path.
Co-developed-by: John Ogness <john.ogness@linutronix.de>
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Signed-off-by: Thomas Gleixner (Intel) <tglx@linutronix.de>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20230916192007.608398-6-john.ogness@linutronix.de
In case of hostile takeovers it must be ensured that the previous
owner cannot scribble over the output buffer of the emergency/panic
context. This is achieved by:
- Adding a global output buffer instance for the panic context.
This is the only situation where hostile takeovers can occur and
there is always at most 1 panic context.
- Allocating an output buffer per non-boot console upon console
registration. This buffer is used by the console owner when not
in panic context. (For boot consoles, the existing shared global
legacy output buffer is used instead. Boot console printing will
be synchronized with legacy console printing.)
- Choosing the appropriate buffer is handled in the acquire/release
functions.
Co-developed-by: John Ogness <john.ogness@linutronix.de>
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Signed-off-by: Thomas Gleixner (Intel) <tglx@linutronix.de>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20230916192007.608398-5-john.ogness@linutronix.de
The nbcon boot consoles also need printk buffers that are available
very early. Since the nbcon boot consoles will also be serialized
by the console_lock, they can use the same static printk buffers
that the legacy consoles are using.
Make the legacy static printk buffers available outside of printk.c
so they can be used by nbcon.c.
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20230916192007.608398-4-john.ogness@linutronix.de
Add per console acquire/release functionality.
The state of the console is maintained in the "nbcon_state" atomic
variable.
The console is locked when:
- The 'prio' field contains the priority of the context that owns the
console. Only higher priority contexts are allowed to take over the
lock. A value of 0 (NBCON_PRIO_NONE) means the console is not locked.
- The 'cpu' field denotes on which CPU the console is locked. It is used
to prevent busy waiting on the same CPU. Also it informs the lock owner
that it has lost the lock in a more complex scenario when the lock was
taken over by a higher priority context, released, and taken on another
CPU with the same priority as the interrupted owner.
The acquire mechanism uses a few more fields:
- The 'req_prio' field is used by the handover approach to make the
current owner aware that there is a context with a higher priority
waiting for the friendly handover.
- The 'unsafe' field allows to take over the console in a safe way in the
middle of emitting a message. The field is set only when accessing some
shared resources or when the console device is manipulated. It can be
cleared, for example, after emitting one character when the console
device is in a consistent state.
- The 'unsafe_takeover' field is set when a hostile takeover took the
console in an unsafe state. The console will stay in the unsafe state
until re-initialized.
The acquire mechanism uses three approaches:
1) Direct acquire when the console is not owned or is owned by a lower
priority context and is in a safe state.
2) Friendly handover mechanism uses a request/grant handshake. It is used
when the current owner has lower priority and the console is in an
unsafe state.
The requesting context:
a) Sets its priority into the 'req_prio' field.
b) Waits (with a timeout) for the owning context to unlock the
console.
c) Takes the lock and clears the 'req_prio' field.
The owning context:
a) Observes the 'req_prio' field set on exit from the unsafe
console state.
b) Gives up console ownership by clearing the 'prio' field.
3) Unsafe hostile takeover allows to take over the lock even when the
console is an unsafe state. It is used only in panic() by the final
attempt to flush consoles in a try and hope mode.
Note that separate record buffers are used in panic(). As a result,
the messages can be read and formatted without any risk even after
using the hostile takeover in unsafe state.
The release function simply clears the 'prio' field.
All operations on @console::nbcon_state are atomic cmpxchg based to
handle concurrency.
The acquire/release functions implement only minimal policies:
- Preference for higher priority contexts.
- Protection of the panic CPU.
All other policy decisions must be made at the call sites:
- What is marked as an unsafe section.
- Whether to spin-wait if there is already an owner and the console is
in an unsafe state.
- Whether to attempt an unsafe hostile takeover.
The design allows to implement the well known:
acquire()
output_one_printk_record()
release()
The output of one printk record might be interrupted with a higher priority
context. The new owner is supposed to reprint the entire interrupted record
from scratch.
Co-developed-by: John Ogness <john.ogness@linutronix.de>
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Signed-off-by: Thomas Gleixner (Intel) <tglx@linutronix.de>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20230916192007.608398-3-john.ogness@linutronix.de
The current console/printk subsystem is protected by a Big Kernel Lock,
(aka console_lock) which has ill defined semantics and is more or less
stateless. This puts severe limitations on the console subsystem and
makes forced takeover and output in emergency and panic situations a
fragile endeavour that is based on try and pray.
The goal of non-BKL (nbcon) consoles is to break out of the console lock
jail and to provide a new infrastructure that avoids the pitfalls and
also allows console drivers to be gradually converted over.
The proposed infrastructure aims for the following properties:
- Per console locking instead of global locking
- Per console state that allows to make informed decisions
- Stateful handover and takeover
As a first step, state is added to struct console. The per console state
is an atomic_t using a 32bit bit field.
Reserve state bits, which will be populated later in the series. Wire
it up into the console register/unregister functionality.
It was decided to use a bitfield because using a plain u32 with
mask/shift operations resulted in uncomprehensible code.
Co-developed-by: John Ogness <john.ogness@linutronix.de>
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Signed-off-by: Thomas Gleixner (Intel) <tglx@linutronix.de>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20230916192007.608398-2-john.ogness@linutronix.de
Pull printk fix from Petr Mladek:
- Revert exporting symbols needed for dumping the raw printk buffer in
panic().
I pushed the export prematurely before the user was ready for merging
into the mainline.
* tag 'printk-for-6.6-fixup' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux:
Revert "printk: export symbols for debug modules"
Pull networking updates from Jakub Kicinski:
"Including fixes from netfilter and bpf.
Current release - regressions:
- eth: stmmac: fix failure to probe without MAC interface specified
Current release - new code bugs:
- docs: netlink: fix missing classic_netlink doc reference
Previous releases - regressions:
- deal with integer overflows in kmalloc_reserve()
- use sk_forward_alloc_get() in sk_get_meminfo()
- bpf_sk_storage: fix the missing uncharge in sk_omem_alloc
- fib: avoid warn splat in flow dissector after packet mangling
- skb_segment: call zero copy functions before using skbuff frags
- eth: sfc: check for zero length in EF10 RX prefix
Previous releases - always broken:
- af_unix: fix msg_controllen test in scm_pidfd_recv() for
MSG_CMSG_COMPAT
- xsk: fix xsk_build_skb() dereferencing possible ERR_PTR()
- netfilter:
- nft_exthdr: fix non-linear header modification
- xt_u32, xt_sctp: validate user space input
- nftables: exthdr: fix 4-byte stack OOB write
- nfnetlink_osf: avoid OOB read
- one more fix for the garbage collection work from last release
- igmp: limit igmpv3_newpack() packet size to IP_MAX_MTU
- bpf, sockmap: fix preempt_rt splat when using raw_spin_lock_t
- handshake: fix null-deref in handshake_nl_done_doit()
- ip: ignore dst hint for multipath routes to ensure packets are
hashed across the nexthops
- phy: micrel:
- correct bit assignments for cable test errata
- disable EEE according to the KSZ9477 errata
Misc:
- docs/bpf: document compile-once-run-everywhere (CO-RE) relocations
- Revert "net: macsec: preserve ingress frame ordering", it appears
to have been developed against an older kernel, problem doesn't
exist upstream"
* tag 'net-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (95 commits)
net: enetc: distinguish error from valid pointers in enetc_fixup_clear_rss_rfs()
Revert "net: team: do not use dynamic lockdep key"
net: hns3: remove GSO partial feature bit
net: hns3: fix the port information display when sfp is absent
net: hns3: fix invalid mutex between tc qdisc and dcb ets command issue
net: hns3: fix debugfs concurrency issue between kfree buffer and read
net: hns3: fix byte order conversion issue in hclge_dbg_fd_tcam_read()
net: hns3: Support query tx timeout threshold by debugfs
net: hns3: fix tx timeout issue
net: phy: Provide Module 4 KSZ9477 errata (DS80000754C)
netfilter: nf_tables: Unbreak audit log reset
netfilter: ipset: add the missing IP_SET_HASH_WITH_NET0 macro for ip_set_hash_netportnet.c
netfilter: nft_set_rbtree: skip sync GC for new elements in this transaction
netfilter: nf_tables: uapi: Describe NFTA_RULE_CHAIN_ID
netfilter: nfnetlink_osf: avoid OOB read
netfilter: nftables: exthdr: fix 4-byte stack OOB write
selftests/bpf: Check bpf_sk_storage has uncharged sk_omem_alloc
bpf: bpf_sk_storage: Fix the missing uncharge in sk_omem_alloc
bpf: bpf_sk_storage: Fix invalid wait context lockdep report
s390/bpf: Pass through tail call counter in trampolines
...
The commit c83597fa5d ("bpf: Refactor some inode/task/sk storage functions
for reuse"), refactored the bpf_{sk,task,inode}_storage_free() into
bpf_local_storage_unlink_nolock() which then later renamed to
bpf_local_storage_destroy(). The commit accidentally passed the
"bool uncharge_mem = false" argument to bpf_selem_unlink_storage_nolock()
which then stopped the uncharge from happening to the sk->sk_omem_alloc.
This missing uncharge only happens when the sk is going away (during
__sk_destruct).
This patch fixes it by always passing "uncharge_mem = true". It is a
noop to the task/inode/cgroup storage because they do not have the
map_local_storage_(un)charge enabled in the map_ops. A followup patch
will be done in bpf-next to remove the uncharge_mem argument.
A selftest is added in the next patch.
Fixes: c83597fa5d ("bpf: Refactor some inode/task/sk storage functions for reuse")
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230901231129.578493-3-martin.lau@linux.dev
'./test_progs -t test_local_storage' reported a splat:
[ 27.137569] =============================
[ 27.138122] [ BUG: Invalid wait context ]
[ 27.138650] 6.5.0-03980-gd11ae1b16b0a #247 Tainted: G O
[ 27.139542] -----------------------------
[ 27.140106] test_progs/1729 is trying to lock:
[ 27.140713] ffff8883ef047b88 (stock_lock){-.-.}-{3:3}, at: local_lock_acquire+0x9/0x130
[ 27.141834] other info that might help us debug this:
[ 27.142437] context-{5:5}
[ 27.142856] 2 locks held by test_progs/1729:
[ 27.143352] #0: ffffffff84bcd9c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire+0x4/0x40
[ 27.144492] #1: ffff888107deb2c0 (&storage->lock){..-.}-{2:2}, at: bpf_local_storage_update+0x39e/0x8e0
[ 27.145855] stack backtrace:
[ 27.146274] CPU: 0 PID: 1729 Comm: test_progs Tainted: G O 6.5.0-03980-gd11ae1b16b0a #247
[ 27.147550] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
[ 27.149127] Call Trace:
[ 27.149490] <TASK>
[ 27.149867] dump_stack_lvl+0x130/0x1d0
[ 27.152609] dump_stack+0x14/0x20
[ 27.153131] __lock_acquire+0x1657/0x2220
[ 27.153677] lock_acquire+0x1b8/0x510
[ 27.157908] local_lock_acquire+0x29/0x130
[ 27.159048] obj_cgroup_charge+0xf4/0x3c0
[ 27.160794] slab_pre_alloc_hook+0x28e/0x2b0
[ 27.161931] __kmem_cache_alloc_node+0x51/0x210
[ 27.163557] __kmalloc+0xaa/0x210
[ 27.164593] bpf_map_kzalloc+0xbc/0x170
[ 27.165147] bpf_selem_alloc+0x130/0x510
[ 27.166295] bpf_local_storage_update+0x5aa/0x8e0
[ 27.167042] bpf_fd_sk_storage_update_elem+0xdb/0x1a0
[ 27.169199] bpf_map_update_value+0x415/0x4f0
[ 27.169871] map_update_elem+0x413/0x550
[ 27.170330] __sys_bpf+0x5e9/0x640
[ 27.174065] __x64_sys_bpf+0x80/0x90
[ 27.174568] do_syscall_64+0x48/0xa0
[ 27.175201] entry_SYSCALL_64_after_hwframe+0x6e/0xd8
[ 27.175932] RIP: 0033:0x7effb40e41ad
[ 27.176357] Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d8
[ 27.179028] RSP: 002b:00007ffe64c21fc8 EFLAGS: 00000202 ORIG_RAX: 0000000000000141
[ 27.180088] RAX: ffffffffffffffda RBX: 00007ffe64c22768 RCX: 00007effb40e41ad
[ 27.181082] RDX: 0000000000000020 RSI: 00007ffe64c22008 RDI: 0000000000000002
[ 27.182030] RBP: 00007ffe64c21ff0 R08: 0000000000000000 R09: 00007ffe64c22788
[ 27.183038] R10: 0000000000000064 R11: 0000000000000202 R12: 0000000000000000
[ 27.184006] R13: 00007ffe64c22788 R14: 00007effb42a1000 R15: 0000000000000000
[ 27.184958] </TASK>
It complains about acquiring a local_lock while holding a raw_spin_lock.
It means it should not allocate memory while holding a raw_spin_lock
since it is not safe for RT.
raw_spin_lock is needed because bpf_local_storage supports tracing
context. In particular for task local storage, it is easy to
get a "current" task PTR_TO_BTF_ID in tracing bpf prog.
However, task (and cgroup) local storage has already been moved to
bpf mem allocator which can be used after raw_spin_lock.
The splat is for the sk storage. For sk (and inode) storage,
it has not been moved to bpf mem allocator. Using raw_spin_lock or not,
kzalloc(GFP_ATOMIC) could theoretically be unsafe in tracing context.
However, the local storage helper requires a verifier accepted
sk pointer (PTR_TO_BTF_ID), it is hypothetical if that (mean running
a bpf prog in a kzalloc unsafe context and also able to hold a verifier
accepted sk pointer) could happen.
This patch avoids kzalloc after raw_spin_lock to silent the splat.
There is an existing kzalloc before the raw_spin_lock. At that point,
a kzalloc is very likely required because a lookup has just been done
before. Thus, this patch always does the kzalloc before acquiring
the raw_spin_lock and remove the later kzalloc usage after the
raw_spin_lock. After this change, it will have a charge and then
uncharge during the syscall bpf_map_update_elem() code path.
This patch opts for simplicity and not continue the old
optimization to save one charge and uncharge.
This issue is dated back to the very first commit of bpf_sk_storage
which had been refactored multiple times to create task, inode, and
cgroup storage. This patch uses a Fixes tag with a more recent
commit that should be easier to do backport.
Fixes: b00fa38a9c ("bpf: Enable non-atomic allocations in local storage")
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230901231129.578493-2-martin.lau@linux.dev
__bpf_prog_enter_recur() assigns bpf_tramp_run_ctx::saved_run_ctx before
performing the recursion check which means in case of a recursion
__bpf_prog_exit_recur() uses the previously set bpf_tramp_run_ctx::saved_run_ctx
value.
__bpf_prog_enter_sleepable_recur() assigns bpf_tramp_run_ctx::saved_run_ctx
after the recursion check which means in case of a recursion
__bpf_prog_exit_sleepable_recur() uses an uninitialized value. This does not
look right. If I read the entry trampoline code right, then bpf_tramp_run_ctx
isn't initialized upfront.
Align __bpf_prog_enter_sleepable_recur() with __bpf_prog_enter_recur() and
set bpf_tramp_run_ctx::saved_run_ctx before the recursion check is made.
Remove the assignment of saved_run_ctx in kern_sys_bpf() since it happens
a few cycles later.
Fixes: e384c7b7b4 ("bpf, x86: Create bpf_tramp_run_ctx on the caller thread's stack")
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20230830080405.251926-3-bigeasy@linutronix.de
If __bpf_prog_enter_sleepable_recur() detects recursion then it returns
0 without undoing rcu_read_lock_trace(), migrate_disable() or
decrementing the recursion counter. This is fine in the JIT case because
the JIT code will jump in the 0 case to the end and invoke the matching
exit trampoline (__bpf_prog_exit_sleepable_recur()).
This is not the case in kern_sys_bpf() which returns directly to the
caller with an error code.
Add __bpf_prog_exit_sleepable_recur() as clean up in the recursion case.
Fixes: b1d18a7574 ("bpf: Extend sys_bpf commands for bpf_syscall programs.")
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20230830080405.251926-2-bigeasy@linutronix.de
Pull Kbuild updates from Masahiro Yamada:
- Enable -Wenum-conversion warning option
- Refactor the rpm-pkg target
- Fix scripts/setlocalversion to consider annotated tags for rt-kernel
- Add a jump key feature for the search menu of 'make nconfig'
- Support Qt6 for 'make xconfig'
- Enable -Wformat-overflow, -Wformat-truncation, -Wstringop-overflow,
and -Wrestrict warnings for W=1 builds
- Replace <asm/export.h> with <linux/export.h> for alpha, ia64, and
sparc
- Support DEB_BUILD_OPTIONS=parallel=N for the debian source package
- Refactor scripts/Makefile.modinst and fix some modules_sign issues
- Add a new Kconfig env variable to warn symbols that are not defined
anywhere
- Show help messages of config fragments in 'make help'
* tag 'kbuild-v6.6' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (62 commits)
kconfig: fix possible buffer overflow
kbuild: Show marked Kconfig fragments in "help"
kconfig: add warn-unknown-symbols sanity check
kbuild: dummy-tools: make MPROFILE_KERNEL checks work on BE
Documentation/llvm: refresh docs
modpost: Skip .llvm.call-graph-profile section check
kbuild: support modules_sign for external modules as well
kbuild: support 'make modules_sign' with CONFIG_MODULE_SIG_ALL=n
kbuild: move more module installation code to scripts/Makefile.modinst
kbuild: reduce the number of mkdir calls during modules_install
kbuild: remove $(MODLIB)/source symlink
kbuild: move depmod rule to scripts/Makefile.modinst
kbuild: add modules_sign to no-{compiler,sync-config}-targets
kbuild: do not run depmod for 'make modules_sign'
kbuild: deb-pkg: support DEB_BUILD_OPTIONS=parallel=N in debian/rules
alpha: remove <asm/export.h>
alpha: replace #include <asm/export.h> with #include <linux/export.h>
ia64: remove <asm/export.h>
ia64: replace #include <asm/export.h> with #include <linux/export.h>
sparc: remove <asm/export.h>
...
Pull printk updates from Petr Mladek:
- Do not try to get the console lock when it is not need or useful in
panic()
- Replace the global console_suspended state by a per-console flag
- Export symbols needed for dumping the raw printk buffer in panic()
- Fix documentation of printf formats for integer types
- Moved Sergey Senozhatsky to the reviewer role
- Misc cleanups
* tag 'printk-for-6.6' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux:
printk: export symbols for debug modules
lib: test_scanf: Add explicit type cast to result initialization in test_number_prefix()
printk: ringbuffer: Fix truncating buffer size min_t cast
printk: Rename abandon_console_lock_in_panic() to other_cpu_in_panic()
printk: Add per-console suspended state
printk: Consolidate console deferred printing
printk: Do not take console lock for console_flush_on_panic()
printk: Keep non-panic-CPUs out of console lock
printk: Reduce console_unblank() usage in unsafe scenarios
kdb: Do not assume write() callback available
docs: printk-formats: Treat char as always unsigned
docs: printk-formats: Fix hex printing of signed values
MAINTAINERS: adjust printk/vsprintf entries
Currently the Kconfig fragments in kernel/configs and arch/*/configs
that aren't used internally aren't discoverable through "make help",
which consists of hard-coded lists of config fragments. Instead, list
all the fragment targets that have a "# Help: " comment prefix so the
targets can be generated dynamically.
Add logic to the Makefile to search for and display the fragment and
comment. Add comments to fragments that are intended to be direct targets.
Signed-off-by: Kees Cook <keescook@chromium.org>
Co-developed-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Pull probes updates from Masami Hiramatsu:
- kprobes: use struct_size() for variable size kretprobe_instance data
structure.
- eprobe: Simplify trace_eprobe list iteration.
- probe events: Data structure field access support on BTF argument.
- Update BTF argument support on the functions in the kernel
loadable modules (only loaded modules are supported).
- Move generic BTF access function (search function prototype and
get function parameters) to a separated file.
- Add a function to search a member of data structure in BTF.
- Support accessing BTF data structure member from probe args by
C-like arrow('->') and dot('.') operators. e.g.
't sched_switch next=next->pid vruntime=next->se.vruntime'
- Support accessing BTF data structure member from $retval. e.g.
'f getname_flags%return +0($retval->name):string'
- Add string type checking if BTF type info is available. This will
reject if user specify ":string" type for non "char pointer"
type.
- Automatically assume the fprobe event as a function return event
if $retval is used.
- selftests/ftrace: Add BTF data field access test cases.
- Documentation: Update fprobe event example with BTF data field.
* tag 'probes-v6.6' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
Documentation: tracing: Update fprobe event example with BTF field
selftests/ftrace: Add BTF fields access testcases
tracing/fprobe-event: Assume fprobe is a return event by $retval
tracing/probes: Add string type check with BTF
tracing/probes: Support BTF field access from $retval
tracing/probes: Support BTF based data structure field access
tracing/probes: Add a function to search a member of a struct/union
tracing/probes: Move finding func-proto API and getting func-param API to trace_btf
tracing/probes: Support BTF argument on module functions
tracing/eprobe: Iterate trace_eprobe directly
kernel: kprobes: Use struct_size()
Pull more tracing updates from Steven Rostedt:
"Tracing fixes and clean ups:
- Replace strlcpy() with strscpy()
- Initialize the pipe cpumask to zero on allocation
- Use within_module() instead of open coding it
- Remove extra space in hwlat_detectory/mode output
- Use LIST_HEAD() instead of open coding it
- A bunch of clean ups and fixes for the cpumask filter
- Set local da_mon_##name to static
- Fix race in snapshot buffer between cpu write and swap"
* tag 'trace-v6.6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
tracing/filters: Fix coding style issues
tracing/filters: Change parse_pred() cpulist ternary into an if block
tracing/filters: Fix double-free of struct filter_pred.mask
tracing/filters: Fix error-handling of cpulist parsing buffer
tracing: Zero the pipe cpumask on alloc to avoid spurious -EBUSY
ftrace: Use LIST_HEAD to initialize clear_hash
ftrace: Use within_module to check rec->ip within specified module.
tracing: Replace strlcpy with strscpy in trace/events/task.h
tracing: Fix race issue between cpu buffer write and swap
tracing: Remove extra space at the end of hwlat_detector/mode
rv: Set variable 'da_mon_##name' to static
Pull timer fix from Ingo Molnar:
"Fix false positive 'softirq work is pending' messages on -rt kernels,
caused by a buggy factoring-out of existing code"
* tag 'timers-urgent-2023-09-02' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
tick/rcu: Fix false positive "softirq work is pending" messages
Pull CPU hotplug fix from Ingo Molnar:
"Fix a CPU hotplug related deadlock between the task which initiates
and controls a CPU hot-unplug operation vs. the CFS bandwidth timer"
* tag 'smp-urgent-2023-09-02' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
cpu/hotplug: Prevent self deadlock on CPU hot-unplug
Pull scheduler fixes from Ingo Molnar:
"Miscellaneous scheduler fixes: a reporting fix, a static symbol fix,
and a kernel-doc fix"
* tag 'sched-urgent-2023-09-02' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/core: Report correct state for TASK_IDLE | TASK_FREEZABLE
sched/fair: Make update_entity_lag() static
sched/core: Add kernel-doc for set_cpus_allowed_ptr()
Sudip Mukherjee reports that the mips sb1250_swarm_defconfig build fails
with the current kernel. It isn't actually MIPS-specific, it's just
that that defconfig does not have CGROUP_SCHED enabled like most configs
do, and as such shows this error:
kernel/cgroup/cgroup.c: In function 'cgroup_local_stat_show':
kernel/cgroup/cgroup.c:3699:15: error: implicit declaration of function 'cgroup_tryget_css'; did you mean 'cgroup_tryget'? [-Werror=implicit-function-declaration]
3699 | css = cgroup_tryget_css(cgrp, ss);
| ^~~~~~~~~~~~~~~~~
| cgroup_tryget
kernel/cgroup/cgroup.c:3699:13: warning: assignment to 'struct cgroup_subsys_state *' from 'int' makes pointer from integer without a cast [-Wint-conversion]
3699 | css = cgroup_tryget_css(cgrp, ss);
| ^
because cgroup_tryget_css() only exists when CGROUP_SCHED is enabled,
and the cgroup_local_stat_show() function should similarly be guarded by
that config option.
Move things around a bit to fix this all.
Fixes: d1d4ff5d11 ("cgroup: put cgroup_tryget_css() inside CONFIG_CGROUP_SCHED")
Reported-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The pipe cpumask used to serialize opens between the main and percpu
trace pipes is not zeroed or initialized. This can result in
spurious -EBUSY returns if underlying memory is not fully zeroed.
This has been observed by immediate failure to read the main
trace_pipe file on an otherwise newly booted and idle system:
# cat /sys/kernel/debug/tracing/trace_pipe
cat: /sys/kernel/debug/tracing/trace_pipe: Device or resource busy
Zero the allocation of pipe_cpumask to avoid the problem.
Link: https://lore.kernel.org/linux-trace-kernel/20230831125500.986862-1-bfoster@redhat.com
Cc: stable@vger.kernel.org
Fixes: c2489bb7e6 ("tracing: Introduce pipe_cpumask to avoid race on trace_pipes")
Reviewed-by: Zheng Yejian <zhengyejian1@huawei.com>
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Warning happened in rb_end_commit() at code:
if (RB_WARN_ON(cpu_buffer, !local_read(&cpu_buffer->committing)))
WARNING: CPU: 0 PID: 139 at kernel/trace/ring_buffer.c:3142
rb_commit+0x402/0x4a0
Call Trace:
ring_buffer_unlock_commit+0x42/0x250
trace_buffer_unlock_commit_regs+0x3b/0x250
trace_event_buffer_commit+0xe5/0x440
trace_event_buffer_reserve+0x11c/0x150
trace_event_raw_event_sched_switch+0x23c/0x2c0
__traceiter_sched_switch+0x59/0x80
__schedule+0x72b/0x1580
schedule+0x92/0x120
worker_thread+0xa0/0x6f0
It is because the race between writing event into cpu buffer and swapping
cpu buffer through file per_cpu/cpu0/snapshot:
Write on CPU 0 Swap buffer by per_cpu/cpu0/snapshot on CPU 1
-------- --------
tracing_snapshot_write()
[...]
ring_buffer_lock_reserve()
cpu_buffer = buffer->buffers[cpu]; // 1. Suppose find 'cpu_buffer_a';
[...]
rb_reserve_next_event()
[...]
ring_buffer_swap_cpu()
if (local_read(&cpu_buffer_a->committing))
goto out_dec;
if (local_read(&cpu_buffer_b->committing))
goto out_dec;
buffer_a->buffers[cpu] = cpu_buffer_b;
buffer_b->buffers[cpu] = cpu_buffer_a;
// 2. cpu_buffer has swapped here.
rb_start_commit(cpu_buffer);
if (unlikely(READ_ONCE(cpu_buffer->buffer)
!= buffer)) { // 3. This check passed due to 'cpu_buffer->buffer'
[...] // has not changed here.
return NULL;
}
cpu_buffer_b->buffer = buffer_a;
cpu_buffer_a->buffer = buffer_b;
[...]
// 4. Reserve event from 'cpu_buffer_a'.
ring_buffer_unlock_commit()
[...]
cpu_buffer = buffer->buffers[cpu]; // 5. Now find 'cpu_buffer_b' !!!
rb_commit(cpu_buffer)
rb_end_commit() // 6. WARN for the wrong 'committing' state !!!
Based on above analysis, we can easily reproduce by following testcase:
``` bash
#!/bin/bash
dmesg -n 7
sysctl -w kernel.panic_on_warn=1
TR=/sys/kernel/tracing
echo 7 > ${TR}/buffer_size_kb
echo "sched:sched_switch" > ${TR}/set_event
while [ true ]; do
echo 1 > ${TR}/per_cpu/cpu0/snapshot
done &
while [ true ]; do
echo 1 > ${TR}/per_cpu/cpu0/snapshot
done &
while [ true ]; do
echo 1 > ${TR}/per_cpu/cpu0/snapshot
done &
```
To fix it, IIUC, we can use smp_call_function_single() to do the swap on
the target cpu where the buffer is located, so that above race would be
avoided.
Link: https://lore.kernel.org/linux-trace-kernel/20230831132739.4070878-1-zhengyejian1@huawei.com
Cc: <mhiramat@kernel.org>
Fixes: f1affcaaa8 ("tracing: Add snapshot in the per_cpu trace directories")
Signed-off-by: Zheng Yejian <zhengyejian1@huawei.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Pull tracing updates from Steven Rostedt:
"User visible changes:
- Added a way to easier filter with cpumasks:
# echo 'cpumask & CPUS{17-42}' > /sys/kernel/tracing/events/ipi_send_cpumask/filter
- Show actual size of ring buffer after modifying the ring buffer
size via buffer_size_kb.
Currently it just returns what was written, but the actual size
rounds up to the sub buffer size. Show that real size instead.
Major changes:
- Added "eventfs". This is the code that handles the inodes and
dentries of tracefs/events directory. As there are thousands of
events, and each event has several inodes and dentries that
currently exist even when tracing is never used, they take up
precious memory. Instead, eventfs will allocate the inodes and
dentries in a JIT way (similar to what procfs does). There is now
metadata that handles the events and subdirectories, and will
create the inodes and dentries when they are used.
Note, I also have patches that remove the subdirectory meta data,
but will wait till the next merge window before applying them. It's
a little more complex, and I want to make sure the dynamic code
works properly before adding more complexity, making it easier to
revert if need be.
Minor changes:
- Optimization to user event list traversal
- Remove intermediate permission of tracefs files (note the
intermediate permission removes all access to the files so it is
not a security concern, but just a clean up)
- Add the complex fix to FORTIFY_SOURCE to the kernel stack event
logic
- Other minor cleanups"
* tag 'trace-v6.6' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (29 commits)
tracefs: Remove kerneldoc from struct eventfs_file
tracefs: Avoid changing i_mode to a temp value
tracing/user_events: Optimize safe list traversals
ftrace: Remove empty declaration ftrace_enable_daemon() and ftrace_disable_daemon()
tracing: Remove unused function declarations
tracing/filters: Document cpumask filtering
tracing/filters: Further optimise scalar vs cpumask comparison
tracing/filters: Optimise CPU vs cpumask filtering when the user mask is a single CPU
tracing/filters: Optimise scalar vs cpumask filtering when the user mask is a single CPU
tracing/filters: Optimise cpumask vs cpumask filtering when user mask is a single CPU
tracing/filters: Enable filtering the CPU common field by a cpumask
tracing/filters: Enable filtering a scalar field by a cpumask
tracing/filters: Enable filtering a cpumask field by another cpumask
tracing/filters: Dynamically allocate filter_pred.regex
test: ftrace: Fix kprobe test for eventfs
eventfs: Move tracing/events to eventfs
eventfs: Implement removal of meta data from eventfs
eventfs: Implement functions to create files and dirs when accessed
eventfs: Implement eventfs lookup, read, open functions
eventfs: Implement eventfs file add functions
...
Pull workqueue updates from Tejun Heo:
- Unbound workqueues now support more flexible affinity scopes.
The default behavior is to soft-affine according to last level cache
boundaries. A work item queued from a given LLC is executed by a
worker running on the same LLC but the worker may be moved across
cache boundaries as the scheduler sees fit. On machines which
multiple L3 caches, which are becoming more popular along with
chiplet designs, this improves cache locality while not harming work
conservation too much.
Unbound workqueues are now also a lot more flexible in terms of
execution affinity. Differeing levels of affinity scopes are
supported and both the default and per-workqueue affinity settings
can be modified dynamically. This should help working around amny of
sub-optimal behaviors observed recently with asymmetric ARM CPUs.
This involved signficant restructuring of workqueue code. Nothing was
reported yet but there's some risk of subtle regressions. Should keep
an eye out.
- Rescuer workers now has more identifiable comms.
- workqueue.unbound_cpus added so that CPUs which can be used by
workqueue can be constrained early during boot.
- Now that all the in-tree users have been flushed out, trigger warning
if system-wide workqueues are flushed.
* tag 'wq-for-6.6' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: (31 commits)
workqueue: fix data race with the pwq->stats[] increment
workqueue: Rename rescuer kworker
workqueue: Make default affinity_scope dynamically updatable
workqueue: Add "Affinity Scopes and Performance" section to documentation
workqueue: Implement non-strict affinity scope for unbound workqueues
workqueue: Add workqueue_attrs->__pod_cpumask
workqueue: Factor out need_more_worker() check and worker wake-up
workqueue: Factor out work to worker assignment and collision handling
workqueue: Add multiple affinity scopes and interface to select them
workqueue: Modularize wq_pod_type initialization
workqueue: Add tools/workqueue/wq_dump.py which prints out workqueue configuration
workqueue: Generalize unbound CPU pods
workqueue: Factor out clearing of workqueue-only attrs fields
workqueue: Factor out actual cpumask calculation to reduce subtlety in wq_update_pod()
workqueue: Initialize unbound CPU pods later in the boot
workqueue: Move wq_pod_init() below workqueue_init()
workqueue: Rename NUMA related names to use pod instead
workqueue: Rename workqueue_attrs->no_numa to ->ordered
workqueue: Make unbound workqueues to use per-cpu pool_workqueues
workqueue: Call wq_update_unbound_numa() on all CPUs in NUMA node on CPU hotplug
...
Pull cgroup updates from Tejun Heo:
- Per-cpu cpu usage stats are now tracked
This currently isn't printed out in the cgroupfs interface and can
only be accessed through e.g. BPF. Should decide on a not-too-ugly
way to show per-cpu stats in cgroupfs
- cpuset received some cleanups and prepatory patches for the pending
cpus.exclusive patchset which will allow cpuset partitions to be
created below non-partition parents, which should ease the management
of partition cpusets
- A lot of code and documentation cleanup patches
- tools/testing/selftests/cgroup/test_cpuset.c added
* tag 'cgroup-for-6.6' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: (32 commits)
cgroup: Avoid -Wstringop-overflow warnings
cgroup:namespace: Remove unused cgroup_namespaces_init()
cgroup/rstat: Record the cumulative per-cpu time of cgroup and its descendants
cgroup: clean up if condition in cgroup_pidlist_start()
cgroup: fix obsolete function name in cgroup_destroy_locked()
Documentation: cgroup-v2.rst: Correct number of stats entries
cgroup: fix obsolete function name above css_free_rwork_fn()
cgroup/cpuset: fix kernel-doc
cgroup: clean up printk()
cgroup: fix obsolete comment above cgroup_create()
docs: cgroup-v1: fix typo
docs: cgroup-v1: correct the term of Page Cache organization in inode
cgroup/misc: Store atomic64_t reads to u64
cgroup/misc: Change counters to be explicit 64bit types
cgroup/misc: update struct members descriptions
cgroup: remove cgrp->kn check in css_populate_dir()
cgroup: fix obsolete function name
cgroup: use cached local variable parent in for loop
cgroup: remove obsolete comment above struct cgroupstats
cgroup: put cgroup_tryget_css() inside CONFIG_CGROUP_SCHED
...
Pull percpu updates from Dennis Zhou:
"One bigger change to percpu_counter's api allowing for init and
destroy of multiple counters via percpu_counter_init_many() and
percpu_counter_destroy_many(). This is used to help begin remediating
a performance regression with percpu rss stats.
Additionally, it seems larger core count machines are feeling the
burden of the single threaded allocation of percpu. Mateusz is
thinking about it and I will spend some time on it too.
percpu:
- A couple cleanups by Baoquan He and Bibo Mao. The only behavior
change is to start printing messages if we're under the warn limit
for failed atomic allocations.
percpu_counter:
- Shakeel introduced percpu counters into mm_struct which caused
percpu allocations be on the hot path [1]. Originally I spent some
time trying to improve the percpu allocator, but instead preferred
what Mateusz Guzik proposed grouping at the allocation site,
percpu_counter_init_many(). This allows a single percpu allocation
to be shared by the counters. I like this approach because it
creates a shared lifetime by the allocations. Additionally, I
believe many inits have higher level synchronization requirements,
like percpu_counter does against HOTPLUG_CPU. Therefore we can
group these optimizations together"
Link: https://lore.kernel.org/linux-mm/20221024052841.3291983-1-shakeelb@google.com/ [1]
* tag 'percpu-for-6.6' of git://git.kernel.org/pub/scm/linux/kernel/git/dennis/percpu:
kernel/fork: group allocation/free of per-cpu counters for mm struct
pcpcntr: add group allocation/free
mm/percpu.c: print error message too if atomic alloc failed
mm/percpu.c: optimize the code in pcpu_setup_first_chunk() a little bit
mm/percpu.c: remove redundant check
mm/percpu: Remove some local variables in pcpu_populate_pte
Pull tty/serial driver updates from Greg KH:
"Here is the big set of tty and serial driver changes for 6.6-rc1.
Lots of cleanups in here this cycle, and some driver updates. Short
summary is:
- Jiri's continued work to make the tty code and apis be a bit more
sane with regards to modern kernel coding style and types
- cpm_uart driver updates
- n_gsm updates and fixes
- meson driver updates
- sc16is7xx driver updates
- 8250 driver updates for different hardware types
- qcom-geni driver fixes
- tegra serial driver change
- stm32 driver updates
- synclink_gt driver cleanups
- tty structure size reduction
All of these have been in linux-next this week with no reported
issues. The last bit of cleanups from Jiri and the tty structure size
reduction came in last week, a bit late but as they were just style
changes and size reductions, I figured they should get into this merge
cycle so that others can work on top of them with no merge conflicts"
* tag 'tty-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (199 commits)
tty: shrink the size of struct tty_struct by 40 bytes
tty: n_tty: deduplicate copy code in n_tty_receive_buf_real_raw()
tty: n_tty: extract ECHO_OP processing to a separate function
tty: n_tty: unify counts to size_t
tty: n_tty: use u8 for chars and flags
tty: n_tty: simplify chars_in_buffer()
tty: n_tty: remove unsigned char casts from character constants
tty: n_tty: move newline handling to a separate function
tty: n_tty: move canon handling to a separate function
tty: n_tty: use MASK() for masking out size bits
tty: n_tty: make n_tty_data::num_overrun unsigned
tty: n_tty: use time_is_before_jiffies() in n_tty_receive_overrun()
tty: n_tty: use 'num' for writes' counts
tty: n_tty: use output character directly
tty: n_tty: make flow of n_tty_receive_buf_common() a bool
Revert "tty: serial: meson: Add a earlycon for the T7 SoC"
Documentation: devices.txt: Fix minors for ttyCPM*
Documentation: devices.txt: Remove ttySIOC*
Documentation: devices.txt: Remove ttyIOC*
serial: 8250_bcm7271: improve bcm7271 8250 port
...
Pull powerpc updates from Michael Ellerman:
- Add HOTPLUG_SMT support (/sys/devices/system/cpu/smt) and honour the
configured SMT state when hotplugging CPUs into the system
- Combine final TLB flush and lazy TLB mm shootdown IPIs when using the
Radix MMU to avoid a broadcast TLBIE flush on exit
- Drop the exclusion between ptrace/perf watchpoints, and drop the now
unused associated arch hooks
- Add support for the "nohlt" command line option to disable CPU idle
- Add support for -fpatchable-function-entry for ftrace, with GCC >=
13.1
- Rework memory block size determination, and support 256MB size on
systems with GPUs that have hotpluggable memory
- Various other small features and fixes
Thanks to Andrew Donnellan, Aneesh Kumar K.V, Arnd Bergmann, Athira
Rajeev, Benjamin Gray, Christophe Leroy, Frederic Barrat, Gautam
Menghani, Geoff Levand, Hari Bathini, Immad Mir, Jialin Zhang, Joel
Stanley, Jordan Niethe, Justin Stitt, Kajol Jain, Kees Cook, Krzysztof
Kozlowski, Laurent Dufour, Liang He, Linus Walleij, Mahesh Salgaonkar,
Masahiro Yamada, Michal Suchanek, Nageswara R Sastry, Nathan Chancellor,
Nathan Lynch, Naveen N Rao, Nicholas Piggin, Nick Desaulniers, Omar
Sandoval, Randy Dunlap, Reza Arbab, Rob Herring, Russell Currey, Sourabh
Jain, Thomas Gleixner, Trevor Woerner, Uwe Kleine-König, Vaibhav Jain,
Xiongfeng Wang, Yuan Tan, Zhang Rui, and Zheng Zengkai.
* tag 'powerpc-6.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (135 commits)
macintosh/ams: linux/platform_device.h is needed
powerpc/xmon: Reapply "Relax frame size for clang"
powerpc/mm/book3s64: Use 256M as the upper limit with coherent device memory attached
powerpc/mm/book3s64: Fix build error with SPARSEMEM disabled
powerpc/iommu: Fix notifiers being shared by PCI and VIO buses
powerpc/mpc5xxx: Add missing fwnode_handle_put()
powerpc/config: Disable SLAB_DEBUG_ON in skiroot
powerpc/pseries: Remove unused hcall tracing instruction
powerpc/pseries: Fix hcall tracepoints with JUMP_LABEL=n
powerpc: dts: add missing space before {
powerpc/eeh: Use pci_dev_id() to simplify the code
powerpc/64s: Move CPU -mtune options into Kconfig
powerpc/powermac: Fix unused function warning
powerpc/pseries: Rework lppaca_shared_proc() to avoid DEBUG_PREEMPT
powerpc: Don't include lppaca.h in paca.h
powerpc/pseries: Move hcall_vphn() prototype into vphn.h
powerpc/pseries: Move VPHN constants into vphn.h
cxl: Drop unused detach_spa()
powerpc: Drop zalloc_maybe_bootmem()
powerpc/powernv: Use struct opal_prd_msg in more places
...
Pull x86 shadow stack support from Dave Hansen:
"This is the long awaited x86 shadow stack support, part of Intel's
Control-flow Enforcement Technology (CET).
CET consists of two related security features: shadow stacks and
indirect branch tracking. This series implements just the shadow stack
part of this feature, and just for userspace.
The main use case for shadow stack is providing protection against
return oriented programming attacks. It works by maintaining a
secondary (shadow) stack using a special memory type that has
protections against modification. When executing a CALL instruction,
the processor pushes the return address to both the normal stack and
to the special permission shadow stack. Upon RET, the processor pops
the shadow stack copy and compares it to the normal stack copy.
For more information, refer to the links below for the earlier
versions of this patch set"
Link: https://lore.kernel.org/lkml/20220130211838.8382-1-rick.p.edgecombe@intel.com/
Link: https://lore.kernel.org/lkml/20230613001108.3040476-1-rick.p.edgecombe@intel.com/
* tag 'x86_shstk_for_6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (47 commits)
x86/shstk: Change order of __user in type
x86/ibt: Convert IBT selftest to asm
x86/shstk: Don't retry vm_munmap() on -EINTR
x86/kbuild: Fix Documentation/ reference
x86/shstk: Move arch detail comment out of core mm
x86/shstk: Add ARCH_SHSTK_STATUS
x86/shstk: Add ARCH_SHSTK_UNLOCK
x86: Add PTRACE interface for shadow stack
selftests/x86: Add shadow stack test
x86/cpufeatures: Enable CET CR4 bit for shadow stack
x86/shstk: Wire in shadow stack interface
x86: Expose thread features in /proc/$PID/status
x86/shstk: Support WRSS for userspace
x86/shstk: Introduce map_shadow_stack syscall
x86/shstk: Check that signal frame is shadow stack mem
x86/shstk: Check that SSP is aligned on sigreturn
x86/shstk: Handle signals for shadow stack
x86/shstk: Introduce routines modifying shstk
x86/shstk: Handle thread shadow stack
x86/shstk: Add user-mode shadow stack support
...
Pull documentation updates from Jonathan Corbet:
"Documentation work keeps chugging along; this includes:
- Work from Carlos Bilbao to integrate rustdoc output into the
generated HTML documentation. This took some work to figure out how
to do it without slowing the docs build and without creating people
who don't have Rust installed, but Carlos got there
- Move the loongarch and mips architecture documentation under
Documentation/arch/
- Some more maintainer documentation from Jakub
... plus the usual assortment of updates, translations, and fixes"
* tag 'docs-6.6' of git://git.lwn.net/linux: (56 commits)
Docu: genericirq.rst: fix irq-example
input: docs: pxrc: remove reference to phoenix-sim
Documentation: serial-console: Fix literal block marker
docs/mm: remove references to hmm_mirror ops and clean typos
docs/zh_CN: correct regi_chg(),regi_add() to region_chg(),region_add()
Documentation: Fix typos
Documentation/ABI: Fix typos
scripts: kernel-doc: fix macro handling in enums
scripts: kernel-doc: parse DEFINE_DMA_UNMAP_[ADDR|LEN]
Documentation: riscv: Update boot image header since EFI stub is supported
Documentation: riscv: Add early boot document
Documentation: arm: Add bootargs to the table of added DT parameters
docs: kernel-parameters: Refer to the correct bitmap function
doc: update params of memhp_default_state=
docs: Add book to process/kernel-docs.rst
docs: sparse: fix invalid link addresses
docs: vfs: clean up after the iterate() removal
docs: Add a section on surveys to the researcher guidelines
docs: move mips under arch
docs: move loongarch under arch
...
