Implement bpf_send_signal_task kfunc that is similar to
bpf_send_signal_thread and bpf_send_signal helpers but can be used to
send signals to other threads and processes. It also supports sending a
cookie with the signal similar to sigqueue().
If the receiving process establishes a handler for the signal using the
SA_SIGINFO flag to sigaction(), then it can obtain this cookie via the
si_value field of the siginfo_t structure passed as the second argument
to the handler.
Signed-off-by: Puranjay Mohan <puranjay@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20241016084136.10305-2-puranjay@kernel.org
There is a potential infinite loop issue that can occur when using a
combination of tail calls and freplace.
In an upcoming selftest, the attach target for entry_freplace of
tailcall_freplace.c is subprog_tc of tc_bpf2bpf.c, while the tail call in
entry_freplace leads to entry_tc. This results in an infinite loop:
entry_tc -> subprog_tc -> entry_freplace --tailcall-> entry_tc.
The problem arises because the tail_call_cnt in entry_freplace resets to
zero each time entry_freplace is executed, causing the tail call mechanism
to never terminate, eventually leading to a kernel panic.
To fix this issue, the solution is twofold:
1. Prevent updating a program extended by an freplace program to a
prog_array map.
2. Prevent extending a program that is already part of a prog_array map
with an freplace program.
This ensures that:
* If a program or its subprogram has been extended by an freplace program,
it can no longer be updated to a prog_array map.
* If a program has been added to a prog_array map, neither it nor its
subprograms can be extended by an freplace program.
Moreover, an extension program should not be tailcalled. As such, return
-EINVAL if the program has a type of BPF_PROG_TYPE_EXT when adding it to a
prog_array map.
Additionally, fix a minor code style issue by replacing eight spaces with a
tab for proper formatting.
Reviewed-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Leon Hwang <leon.hwang@linux.dev>
Link: https://lore.kernel.org/r/20241015150207.70264-2-leon.hwang@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
bpf_task_from_pid() that currently exists looks up the
struct task_struct corresponding to the pid in the root pid
namespace (init_pid_ns).
This patch adds bpf_task_from_vpid() which looks up the
struct task_struct corresponding to vpid in the pid namespace
of the current process.
This is useful for getting information about other processes
in the same pid namespace.
Signed-off-by: Juntong Deng <juntong.deng@outlook.com>
Link: https://lore.kernel.org/r/AM6PR03MB5848E50DA58F79CDE65433C399442@AM6PR03MB5848.eurprd03.prod.outlook.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The bpf_get_kmem_cache() is to get a slab cache information from a
virtual address like virt_to_cache(). If the address is a pointer
to a slab object, it'd return a valid kmem_cache pointer, otherwise
NULL is returned.
It doesn't grab a reference count of the kmem_cache so the caller is
responsible to manage the access. The returned point is marked as
PTR_UNTRUSTED.
The intended use case for now is to symbolize locks in slab objects
from the lock contention tracepoints.
Suggested-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Roman Gushchin <roman.gushchin@linux.dev> (mm/*)
Acked-by: Vlastimil Babka <vbabka@suse.cz> #mm/slab
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20241010232505.1339892-3-namhyung@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The new "kmem_cache" iterator will traverse the list of slab caches
and call attached BPF programs for each entry. It should check the
argument (ctx.s) if it's NULL before using it.
Now the iteration grabs the slab_mutex only if it traverse the list and
releases the mutex when it runs the BPF program. The kmem_cache entry
is protected by a refcount during the execution.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz> #slab
Link: https://lore.kernel.org/r/20241010232505.1339892-2-namhyung@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
In order to allow pahole add btf_decl_tag("bpf_fastcall") for kfuncs
supporting bpf_fastcall, mark such functions with KF_FASTCALL in
id_set8 objects.
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20240916091712.2929279-4-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
A kfree() call is always used at the end of this function implementation.
Thus specify such a function call only once instead of duplicating it
in a previous if branch.
This issue was detected by using the Coccinelle software.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/bpf/08987123-668c-40f3-a8ee-c3038d94f069@web.de
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
struct btf_kind_operations are not modified in BTF.
Constifying this structures moves some data to a read-only section,
so increase overall security, especially when the structure holds
some function pointers.
On a x86_64, with allmodconfig:
Before:
======
text data bss dec hex filename
184320 7091 548 191959 2edd7 kernel/bpf/btf.o
After:
=====
text data bss dec hex filename
184896 6515 548 191959 2edd7 kernel/bpf/btf.o
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/r/9192ab72b2e9c66aefd6520f359a20297186327f.1726417289.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Brandon reports sporadic, non-sensical spikes in cumulative pressure
time (total=) when reading cpu.pressure at a high rate. This is due to
a race condition between reader aggregation and tasks changing states.
While it affects all states and all resources captured by PSI, in
practice it most likely triggers with CPU pressure, since scheduling
events are so frequent compared to other resource events.
The race context is the live snooping of ongoing stalls during a
pressure read. The read aggregates per-cpu records for stalls that
have concluded, but will also incorporate ad-hoc the duration of any
active state that hasn't been recorded yet. This is important to get
timely measurements of ongoing stalls. Those ad-hoc samples are
calculated on-the-fly up to the current time on that CPU; since the
stall hasn't concluded, it's expected that this is the minimum amount
of stall time that will enter the per-cpu records once it does.
The problem is that the path that concludes the state uses a CPU clock
read that is not synchronized against aggregators; the clock is read
outside of the seqlock protection. This allows aggregators to race and
snoop a stall with a longer duration than will actually be recorded.
With the recorded stall time being less than the last snapshot
remembered by the aggregator, a subsequent sample will underflow and
observe a bogus delta value, resulting in an erratic jump in pressure.
Fix this by moving the clock read of the state change into the seqlock
protection. This ensures no aggregation can snoop live stalls past the
time that's recorded when the state concludes.
Reported-by: Brandon Duffany <brandon@buildbuddy.io>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=219194
Link: https://lore.kernel.org/lkml/20240827121851.GB438928@cmpxchg.org/
Fixes: df77430639 ("psi: Reduce calls to sched_clock() in psi")
Cc: stable@vger.kernel.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Chengming Zhou <chengming.zhou@linux.dev>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Merge tag 'pull-work.unaligned' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull generic unaligned.h cleanups from Al Viro:
"Get rid of architecture-specific <asm/unaligned.h> includes, replacing
them with a single generic <linux/unaligned.h> header file.
It's the second largest (after asm/io.h) class of asm/* includes, and
all but two architectures actually end up using exact same file.
Massage the remaining two (arc and parisc) to do the same and just
move the thing to from asm-generic/unaligned.h to linux/unaligned.h"
[ This is one of those things that we're better off doing outside the
merge window, and would only cause extra conflict noise if it was in
linux-next for the next release due to all the trivial #include line
updates. Rip off the band-aid. - Linus ]
* tag 'pull-work.unaligned' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
move asm/unaligned.h to linux/unaligned.h
arc: get rid of private asm/unaligned.h
parisc: get rid of private asm/unaligned.h
asm/unaligned.h is always an include of asm-generic/unaligned.h;
might as well move that thing to linux/unaligned.h and include
that - there's nothing arch-specific in that header.
auto-generated by the following:
for i in `git grep -l -w asm/unaligned.h`; do
sed -i -e "s/asm\/unaligned.h/linux\/unaligned.h/" $i
done
for i in `git grep -l -w asm-generic/unaligned.h`; do
sed -i -e "s/asm-generic\/unaligned.h/linux\/unaligned.h/" $i
done
git mv include/asm-generic/unaligned.h include/linux/unaligned.h
git mv tools/include/asm-generic/unaligned.h tools/include/linux/unaligned.h
sed -i -e "/unaligned.h/d" include/asm-generic/Kbuild
sed -i -e "s/__ASM_GENERIC/__LINUX/" include/linux/unaligned.h tools/include/linux/unaligned.h
- When sched_ext is in bypass mode (e.g. while disabling the BPF scheduler),
it was using one DSQ to implement global FIFO scheduling as all it has to
do is guaranteeing reasonable forward progress. On multi-socket machines,
this can lead to live-lock conditions under certain workloads. Fixed by
splitting the queue used for FIFO scheduling per NUMA node. This required
several preparation patches.
- Hotplug tests on powerpc could reliably trigger deadlock while enabling a
BPF scheduler. This was caused by cpu_hotplug_lock nesting inside
scx_fork_rwsem and then CPU hotplug path trying to fork a new thread while
holding cpu_hotplug_lock. Fixed by restructuring locking in enable and
disable paths so that the two locks are not coupled. This required several
preparation patches which also fixed a couple other issues in the enable
path.
- A build fix for !CONFIG_SMP.
- Userspace tooling sync and updates.
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Merge tag 'sched_ext-for-6.12-rc1-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/sched_ext
Pull sched_ext fixes from Tejun Heo:
- When sched_ext is in bypass mode (e.g. while disabling the BPF
scheduler), it was using one DSQ to implement global FIFO scheduling
as all it has to do is guaranteeing reasonable forward progress.
On multi-socket machines, this can lead to live-lock conditions under
certain workloads. Fixed by splitting the queue used for FIFO
scheduling per NUMA node. This required several preparation patches.
- Hotplug tests on powerpc could reliably trigger deadlock while
enabling a BPF scheduler.
This was caused by cpu_hotplug_lock nesting inside scx_fork_rwsem and
then CPU hotplug path trying to fork a new thread while holding
cpu_hotplug_lock.
Fixed by restructuring locking in enable and disable paths so that
the two locks are not coupled. This required several preparation
patches which also fixed a couple other issues in the enable path.
- A build fix for !CONFIG_SMP
- Userspace tooling sync and updates
* tag 'sched_ext-for-6.12-rc1-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/sched_ext:
sched_ext: Remove redundant p->nr_cpus_allowed checker
sched_ext: Decouple locks in scx_ops_enable()
sched_ext: Decouple locks in scx_ops_disable_workfn()
sched_ext: Add scx_cgroup_enabled to gate cgroup operations and fix scx_tg_online()
sched_ext: Enable scx_ops_init_task() separately
sched_ext: Fix SCX_TASK_INIT -> SCX_TASK_READY transitions in scx_ops_enable()
sched_ext: Initialize in bypass mode
sched_ext: Remove SCX_OPS_PREPPING
sched_ext: Relocate check_hotplug_seq() call in scx_ops_enable()
sched_ext: Use shorter slice while bypassing
sched_ext: Split the global DSQ per NUMA node
sched_ext: Relocate find_user_dsq()
sched_ext: Allow only user DSQs for scx_bpf_consume(), scx_bpf_dsq_nr_queued() and bpf_iter_scx_dsq_new()
scx_flatcg: Use a user DSQ for fallback instead of SCX_DSQ_GLOBAL
tools/sched_ext: Receive misc updates from SCX repo
sched_ext: Add __COMPAT helpers for features added during v6.12 devel cycle
sched_ext: Build fix for !CONFIG_SMP
- uprobes: fix kernel info leak via "[uprobes]" vma
Fix uprobes not to expose the uninitialized page for trampoline
buffer to user space, which can leak kernel info.
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Merge tag 'probes-fixes-v6.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull probes fix from Masami Hiramatsu:
- uprobes: fix kernel info leak via "[uprobes]" vma
Fix uprobes not to expose the uninitialized page for trampoline
buffer to user space, which can leak kernel info.
* tag 'probes-fixes-v6.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
uprobes: fix kernel info leak via "[uprobes]" vma
xol_add_vma() maps the uninitialized page allocated by __create_xol_area()
into userspace. On some architectures (x86) this memory is readable even
without VM_READ, VM_EXEC results in the same pgprot_t as VM_EXEC|VM_READ,
although this doesn't really matter, debugger can read this memory anyway.
Link: https://lore.kernel.org/all/20240929162047.GA12611@redhat.com/
Reported-by: Will Deacon <will@kernel.org>
Fixes: d4b3b6384f ("uprobes/core: Allocate XOL slots for uprobes use")
Cc: stable@vger.kernel.org
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
There are a few fixes / cleanups from Vincent, Chunhui, and Petr, but the
most important part of this pull request is the Rust community stepping
up to help maintain both C / Rust code for future Rust module support. We
grow the set of modules maintainers by 3 now, and with this hope to scale to
help address what's needed to properly support future Rust module support.
A lot of exciting stuff coming in future kernel releases.
This has been on linux-next for ~ 3 weeks now with no issues.
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Merge tag 'modules-6.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux
Pull module updates from Luis Chamberlain:
"There are a few fixes / cleanups from Vincent, Chunhui, and Petr, but
the most important part of this pull request is the Rust community
stepping up to help maintain both C / Rust code for future Rust module
support. We grow the set of modules maintainers by three now, and with
this hope to scale to help address what's needed to properly support
future Rust module support.
A lot of exciting stuff coming in future kernel releases.
This has been on linux-next for ~ 3 weeks now with no issues"
* tag 'modules-6.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux:
module: Refine kmemleak scanned areas
module: abort module loading when sysfs setup suffer errors
MAINTAINERS: scale modules with more reviewers
module: Clean up the description of MODULE_SIG_<type>
module: Split modules_install compression and in-kernel decompression
The enable path uses three big locks - scx_fork_rwsem, scx_cgroup_rwsem and
cpus_read_lock. Currently, the locks are grabbed together which is prone to
locking order problems.
For example, currently, there is a possible deadlock involving
scx_fork_rwsem and cpus_read_lock. cpus_read_lock has to nest inside
scx_fork_rwsem due to locking order existing in other subsystems. However,
there exists a dependency in the other direction during hotplug if hotplug
needs to fork a new task, which happens in some cases. This leads to the
following deadlock:
scx_ops_enable() hotplug
percpu_down_write(&cpu_hotplug_lock)
percpu_down_write(&scx_fork_rwsem)
block on cpu_hotplug_lock
kthread_create() waits for kthreadd
kthreadd blocks on scx_fork_rwsem
Note that this doesn't trigger lockdep because the hotplug side dependency
bounces through kthreadd.
With the preceding scx_cgroup_enabled change, this can be solved by
decoupling cpus_read_lock, which is needed for static_key manipulations,
from the other two locks.
- Move the first block of static_key manipulations outside of scx_fork_rwsem
and scx_cgroup_rwsem. This is now safe with the preceding
scx_cgroup_enabled change.
- Drop scx_cgroup_rwsem and scx_fork_rwsem between the two task iteration
blocks so that __scx_ops_enabled static_key enabling is outside the two
rwsems.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-and-tested-by: Aboorva Devarajan <aboorvad@linux.ibm.com>
Link: http://lkml.kernel.org/r/8cd0ec0c4c7c1bc0119e61fbef0bee9d5e24022d.camel@linux.ibm.com
The disable path uses three big locks - scx_fork_rwsem, scx_cgroup_rwsem and
cpus_read_lock. Currently, the locks are grabbed together which is prone to
locking order problems. With the preceding scx_cgroup_enabled change, we can
decouple them:
- As cgroup disabling no longer requires modifying a static_key which
requires cpus_read_lock(), no need to grab cpus_read_lock() before
grabbing scx_cgroup_rwsem.
- cgroup can now be independently disabled before tasks are moved back to
the fair class.
Relocate scx_cgroup_exit() invocation before scx_fork_rwsem is grabbed, drop
now unnecessary cpus_read_lock() and move static_key operations out of
scx_fork_rwsem. This decouples all three locks in the disable path.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-and-tested-by: Aboorva Devarajan <aboorvad@linux.ibm.com>
Link: http://lkml.kernel.org/r/8cd0ec0c4c7c1bc0119e61fbef0bee9d5e24022d.camel@linux.ibm.com
If the BPF scheduler does not implement ops.cgroup_init(), scx_tg_online()
didn't set SCX_TG_INITED which meant that ops.cgroup_exit(), even if
implemented, won't be called from scx_tg_offline(). This is because
SCX_HAS_OP(cgroupt_init) is used to test both whether SCX cgroup operations
are enabled and ops.cgroup_init() exists.
Fix it by introducing a separate bool scx_cgroup_enabled to gate cgroup
operations and use SCX_HAS_OP(cgroup_init) only to test whether
ops.cgroup_init() exists. Make all cgroup operations consistently use
scx_cgroup_enabled to test whether cgroup operations are enabled.
scx_cgroup_enabled is added instead of using scx_enabled() to ease planned
locking updates.
Signed-off-by: Tejun Heo <tj@kernel.org>
scx_ops_init_task() and the follow-up scx_ops_enable_task() in the fork path
were gated by scx_enabled() test and thus __scx_ops_enabled had to be turned
on before the first scx_ops_init_task() loop in scx_ops_enable(). However,
if an external entity causes sched_class switch before the loop is complete,
tasks which are not initialized could be switched to SCX.
The following can be reproduced by running a program which keeps toggling a
process between SCHED_OTHER and SCHED_EXT using sched_setscheduler(2).
sched_ext: Invalid task state transition 0 -> 3 for fish[1623]
WARNING: CPU: 1 PID: 1650 at kernel/sched/ext.c:3392 scx_ops_enable_task+0x1a1/0x200
...
Sched_ext: simple (enabling)
RIP: 0010:scx_ops_enable_task+0x1a1/0x200
...
switching_to_scx+0x13/0xa0
__sched_setscheduler+0x850/0xa50
do_sched_setscheduler+0x104/0x1c0
__x64_sys_sched_setscheduler+0x18/0x30
do_syscall_64+0x7b/0x140
entry_SYSCALL_64_after_hwframe+0x76/0x7e
Fix it by gating scx_ops_init_task() separately using
scx_ops_init_task_enabled. __scx_ops_enabled is now set after all tasks are
finished with scx_ops_init_task().
Signed-off-by: Tejun Heo <tj@kernel.org>
scx_ops_enable() has two task iteration loops. The first one calls
scx_ops_init_task() on every task and the latter switches the eligible ones
into SCX. The first loop left the tasks in SCX_TASK_INIT state and then the
second loop switched it into READY before switching the task into SCX.
The distinction between INIT and READY is only meaningful in the fork path
where it's used to tell whether the task finished forking so that we can
tell ops.exit_task() accordingly. Leaving task in INIT state between the two
loops is incosistent with the fork path and incorrect. The following can be
triggered by running a program which keeps toggling a task between
SCHED_OTHER and SCHED_SCX while enabling a task:
sched_ext: Invalid task state transition 1 -> 3 for fish[1526]
WARNING: CPU: 2 PID: 1615 at kernel/sched/ext.c:3393 scx_ops_enable_task+0x1a1/0x200
...
Sched_ext: qmap (enabling+all)
RIP: 0010:scx_ops_enable_task+0x1a1/0x200
...
switching_to_scx+0x13/0xa0
__sched_setscheduler+0x850/0xa50
do_sched_setscheduler+0x104/0x1c0
__x64_sys_sched_setscheduler+0x18/0x30
do_syscall_64+0x7b/0x140
entry_SYSCALL_64_after_hwframe+0x76/0x7e
Fix it by transitioning to READY in the first loop right after
scx_ops_init_task() succeeds.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: David Vernet <void@manifault.com>
scx_ops_enable() used preempt_disable() around the task iteration loop to
switch tasks into SCX to guarantee forward progress of the task which is
running scx_ops_enable(). However, in the gap between setting
__scx_ops_enabled and preeempt_disable(), an external entity can put tasks
including the enabling one into SCX prematurely, which can lead to
malfunctions including stalls.
The bypass mode can wrap the entire enabling operation and guarantee forward
progress no matter what the BPF scheduler does. Use the bypass mode instead
to guarantee forward progress while enabling.
While at it, release and regrab scx_tasks_lock between the two task
iteration locks in scx_ops_enable() for clarity as there is no reason to
keep holding the lock between them.
Signed-off-by: Tejun Heo <tj@kernel.org>
The distinction between SCX_OPS_PREPPING and SCX_OPS_ENABLING is not used
anywhere and only adds confusion. Drop SCX_OPS_PREPPING.
Signed-off-by: Tejun Heo <tj@kernel.org>
check_hotplug_seq() is used to detect CPU hotplug event which occurred while
the BPF scheduler is being loaded so that initialization can be retried if
CPU hotplug events take place before the CPU hotplug callbacks are online.
As such, the best place to call it is in the same cpu_read_lock() section
that enables the CPU hotplug ops. Currently, it is called in the next
cpus_read_lock() block in scx_ops_enable(). The side effect of this
placement is a small window in which hotplug sequence detection can trigger
unnecessarily, which isn't critical.
Move check_hotplug_seq() invocation to the same cpus_read_lock() block as
the hotplug operation enablement to close the window and get the invocation
out of the way for planned locking updates.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: David Vernet <void@manifault.com>
no_llseek had been defined to NULL two years ago, in commit 868941b144
("fs: remove no_llseek")
To quote that commit,
At -rc1 we'll need do a mechanical removal of no_llseek -
git grep -l -w no_llseek | grep -v porting.rst | while read i; do
sed -i '/\<no_llseek\>/d' $i
done
would do it.
Unfortunately, that hadn't been done. Linus, could you do that now, so
that we could finally put that thing to rest? All instances are of the
form
.llseek = no_llseek,
so it's obviously safe.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
While bypassing, tasks are scheduled in FIFO order which favors tasks that
hog CPUs. This can slow down e.g. unloading of the BPF scheduler. While
bypassing, guaranteeing timely forward progress is the main goal. There's no
point in giving long slices. Shorten the time slice used while bypassing
from 20ms to 5ms.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: David Vernet <void@manifault.com>
In the bypass mode, the global DSQ is used to schedule all tasks in simple
FIFO order. All tasks are queued into the global DSQ and all CPUs try to
execute tasks from it. This creates a lot of cross-node cacheline accesses
and scheduling across the node boundaries, and can lead to live-lock
conditions where the system takes tens of minutes to disable the BPF
scheduler while executing in the bypass mode.
Split the global DSQ per NUMA node. Each node has its own global DSQ. When a
task is dispatched to SCX_DSQ_GLOBAL, it's put into the global DSQ local to
the task's CPU and all CPUs in a node only consume its node-local global
DSQ.
This resolves a livelock condition which could be reliably triggered on an
2x EPYC 7642 system by running `stress-ng --race-sched 1024` together with
`stress-ng --workload 80 --workload-threads 10` while repeatedly enabling
and disabling a SCX scheduler.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: David Vernet <void@manifault.com>
To prepare for the addition of find_global_dsq(). No functional changes.
Signed-off-by: tejun heo <tj@kernel.org>
Acked-by: David Vernet <void@manifault.com>
SCX_DSQ_GLOBAL is special in that it can't be used as a priority queue and
is consumed implicitly, but all BPF DSQ related kfuncs could be used on it.
SCX_DSQ_GLOBAL will be split per-node for scalability and those operations
won't make sense anymore. Disallow SCX_DSQ_GLOBAL on scx_bpf_consume(),
scx_bpf_dsq_nr_queued() and bpf_iter_scx_dsq_new(). This means that
SCX_DSQ_GLOBAL can only be used as a dispatch target from BPF schedulers.
With scx_flatcg, which was using SCX_DSQ_GLOBAL as the fallback DSQ,
updated, this shouldn't affect any schedulers.
This leaves find_dsq_for_dispatch() the only user of find_non_local_dsq().
Open code and remove find_non_local_dsq().
Signed-off-by: tejun heo <tj@kernel.org>
Acked-by: David Vernet <void@manifault.com>
This reverts commit fb97d2eb54.
The logging was questionable to begin with, but it seems to actively
deadlock on the task lock.
"On second thought, let's not log core dump failures. 'Tis a silly place"
because if you can't tell your core dump is truncated, maybe you should
just fix your debugger instead of adding bugs to the kernel.
Reported-by: Vegard Nossum <vegard.nossum@oracle.com>
Link: https://lore.kernel.org/all/d122ece6-3606-49de-ae4d-8da88846bef2@oracle.com/
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- uprobes: make trace_uprobe->nhit counter a per-CPU one
This makes uprobe event's hit counter per-CPU for improving
scalability on multi-core environment.
- kprobes: Remove obsoleted declaration for init_test_probes
Remove unused init_test_probes() from header.
- Raw tracepoint probe supports raw tracepoint events on modules.
The tracepoint events using fprobe were introduced in v6.5, but
tracepoints can be compiled in modules. This supports such a case.
This includes the following improvements.
. tracepoint: add a function for iterating over all tracepoints in
all modules.
. tracepoint: Add a function for iterating over tracepoints in a
module.
. tracing/fprobe: Support raw tracepoint events on modules.
. tracing/fprobe: Support raw tracepoints on future loaded modules.
This allows user to add tracepoint events on modules which is
not loaded yet.
. selftests/tracing: Add a test for tracepoint events on modules.
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Merge tag 'probes-v6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull probes updates from Masami Hiramatsu:
- uprobes: make trace_uprobe->nhit counter a per-CPU one
This makes uprobe event's hit counter per-CPU for improving
scalability on multi-core environment
- kprobes: Remove obsoleted declaration for init_test_probes
Remove unused init_test_probes() from header
- Raw tracepoint probe supports raw tracepoint events on modules:
- add a function for iterating over all tracepoints in all modules
- add a function for iterating over tracepoints in a module
- support raw tracepoint events on modules
- support raw tracepoints on future loaded modules
- add a test for tracepoint events on modules"
* tag 'probes-v6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
sefltests/tracing: Add a test for tracepoint events on modules
tracing/fprobe: Support raw tracepoints on future loaded modules
tracing/fprobe: Support raw tracepoint events on modules
tracepoint: Support iterating tracepoints in a loading module
tracepoint: Support iterating over tracepoints on modules
kprobes: Remove obsoleted declaration for init_test_probes
uprobes: turn trace_uprobe's nhit counter to be per-CPU one
* new memblock_estimated_nr_free_pages() helper to replace totalram_pages()
which is less accurate when CONFIG_DEFERRED_STRUCT_PAGE_INIT is set
* fixes for memblock tests
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Merge tag 'memblock-v6.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rppt/memblock
Pull memblock updates from Mike Rapoport:
- new memblock_estimated_nr_free_pages() helper to replace
totalram_pages() which is less accurate when
CONFIG_DEFERRED_STRUCT_PAGE_INIT is set
- fixes for memblock tests
* tag 'memblock-v6.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rppt/memblock:
s390/mm: get estimated free pages by memblock api
kernel/fork.c: get estimated free pages by memblock api
mm/memblock: introduce a new helper memblock_estimated_nr_free_pages()
memblock test: fix implicit declaration of function 'strscpy'
memblock test: fix implicit declaration of function 'isspace'
memblock test: fix implicit declaration of function 'memparse'
memblock test: add the definition of __setup()
memblock test: fix implicit declaration of function 'virt_to_phys'
tools/testing: abstract two init.h into common include directory
memblock tests: include export.h in linkage.h as kernel dose
memblock tests: include memory_hotplug.h in mmzone.h as kernel dose
Currently the Rust support is gated on not having MODVERSIONS enabled,
and as a result an "allmodconfig" build will disable Rust build tests.
While MODVERSIONS configurations are worth build testing, the feature is
not actually meaningful unless you run the result, and I'd rather get
build coverage of Rust than MODVERSIONS. So let's disable MODVERSIONS
for build testing until the Rust side clears up.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Support raw tracepoint events on future loaded (unloaded) modules.
This allows user to create raw tracepoint events which can be used from
module's __init functions.
Note: since the kernel does not have any information about the tracepoints
in the unloaded modules, fprobe events can not check whether the tracepoint
exists nor extend the BTF based arguments.
Link: https://lore.kernel.org/all/172397780593.286558.18360375226968537828.stgit@devnote2/
Suggested-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Add for_each_tracepoint_in_module() function to iterate tracepoints in
a module. This API is needed for handling tracepoints in a loading
module from tracepoint_module_notifier callback function.
This also update for_each_module_tracepoint() to pass the module to
callback function so that it can find module easily.
Link: https://lore.kernel.org/all/172397778740.286558.15781131277732977643.stgit@devnote2/
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Add for_each_module_tracepoint() for iterating over tracepoints
on modules. This is similar to the for_each_kernel_tracepoint()
but only for the tracepoints on modules (not including kernel
built-in tracepoints).
Link: https://lore.kernel.org/all/172397777800.286558.14554748203446214056.stgit@devnote2/
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
trace_uprobe->nhit counter is not incremented atomically, so its value
is questionable in when uprobe is hit on multiple CPUs simultaneously.
Also, doing this shared counter increment across many CPUs causes heavy
cache line bouncing, limiting uprobe/uretprobe performance scaling with
number of CPUs.
Solve both problems by making this a per-CPU counter.
Link: https://lore.kernel.org/all/20240813203409.3985398-1-andrii@kernel.org/
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
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Merge tag 'bpf-next-6.12-struct-fd' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Pull bpf 'struct fd' updates from Alexei Starovoitov:
"This includes struct_fd BPF changes from Al and Andrii"
* tag 'bpf-next-6.12-struct-fd' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next:
bpf: convert bpf_token_create() to CLASS(fd, ...)
security,bpf: constify struct path in bpf_token_create() LSM hook
bpf: more trivial fdget() conversions
bpf: trivial conversions for fdget()
bpf: switch maps to CLASS(fd, ...)
bpf: factor out fetching bpf_map from FD and adding it to used_maps list
bpf: switch fdget_raw() uses to CLASS(fd_raw, ...)
bpf: convert __bpf_prog_get() to CLASS(fd, ...)
move_remote_task_to_local_dsq() is only defined on SMP configs but
scx_disaptch_from_dsq() was calling move_remote_task_to_local_dsq() on UP
configs too causing build failures. Add a dummy
move_remote_task_to_local_dsq() which triggers a warning.
Signed-off-by: Tejun Heo <tj@kernel.org>
Fixes: 4c30f5ce4f ("sched_ext: Implement scx_bpf_dispatch[_vtime]_from_dsq()")
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202409241108.jaocHiDJ-lkp@intel.com/
- Support cross-compiling linux-headers Debian package and kernel-devel
RPM package
- Add support for the linux-debug Pacman package
- Improve module rebuilding speed by factoring out the common code to
scripts/module-common.c
- Separate device tree build rules into scripts/Makefile.dtbs
- Add a new script to generate modules.builtin.ranges, which is useful
for tracing tools to find symbols in built-in modules
- Refactor Kconfig and misc tools
- Update Kbuild and Kconfig documentation
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Merge tag 'kbuild-v6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild updates from Masahiro Yamada:
- Support cross-compiling linux-headers Debian package and kernel-devel
RPM package
- Add support for the linux-debug Pacman package
- Improve module rebuilding speed by factoring out the common code to
scripts/module-common.c
- Separate device tree build rules into scripts/Makefile.dtbs
- Add a new script to generate modules.builtin.ranges, which is useful
for tracing tools to find symbols in built-in modules
- Refactor Kconfig and misc tools
- Update Kbuild and Kconfig documentation
* tag 'kbuild-v6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (51 commits)
kbuild: doc: replace "gcc" in external module description
kbuild: doc: describe the -C option precisely for external module builds
kbuild: doc: remove the description about shipped files
kbuild: doc: drop section numbering, use references in modules.rst
kbuild: doc: throw out the local table of contents in modules.rst
kbuild: doc: remove outdated description of the limitation on -I usage
kbuild: doc: remove description about grepping CONFIG options
kbuild: doc: update the description about Kbuild/Makefile split
kbuild: remove unnecessary export of RUST_LIB_SRC
kbuild: remove append operation on cmd_ld_ko_o
kconfig: cache expression values
kconfig: use hash table to reuse expressions
kconfig: refactor expr_eliminate_dups()
kconfig: add comments to expression transformations
kconfig: change some expr_*() functions to bool
scripts: move hash function from scripts/kconfig/ to scripts/include/
kallsyms: change overflow variable to bool type
kallsyms: squash output_address()
kbuild: add install target for modules.builtin.ranges
scripts: add verifier script for builtin module range data
...
- sort out a few issues with the direct calls to iommu-dma
(Christoph Hellwig, Leon Romanovsky)
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Merge tag 'dma-mapping-6.12-2024-09-24' of git://git.infradead.org/users/hch/dma-mapping
Pull dma-mapping fixes from Christoph Hellwig:
- sort out a few issues with the direct calls to iommu-dma (Christoph
Hellwig, Leon Romanovsky)
* tag 'dma-mapping-6.12-2024-09-24' of git://git.infradead.org/users/hch/dma-mapping:
dma-mapping: report unlimited DMA addressing in IOMMU DMA path
iommu/dma: remove most stubs in iommu-dma.h
dma-mapping: fix vmap and mmap of noncontiougs allocations
- Three build fixes.
- The fix for a stall bug introduced by a recent optimization in sched core
(SM_IDLE).
- Addition of /sys/kernel/sched_ext/enable_seq. While not a fix, it is a
simple addition that distro people want to be able to tell whether an SCX
scheduler has ever been loaded on the system.
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Merge tag 'sched_ext-for-6.12-rc1-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/sched_ext
Pull sched_ext fixes from Tejun Heo:
- Three build fixes
- The fix for a stall bug introduced by a recent optimization in sched
core (SM_IDLE)
- Addition of /sys/kernel/sched_ext/enable_seq. While not a fix, it is
a simple addition that distro people want to be able to tell whether
an SCX scheduler has ever been loaded on the system
* tag 'sched_ext-for-6.12-rc1-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/sched_ext:
sched_ext: Provide a sysfs enable_seq counter
sched_ext: Fix build when !CONFIG_STACKTRACE
sched, sched_ext: Disable SM_IDLE/rq empty path when scx_enabled()
sched: Put task_group::idle under CONFIG_GROUP_SCHED_WEIGHT
sched: Add dummy version of sched_group_set_idle()
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Merge tag 'pci-v6.12-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci
Pull pci updates from Bjorn Helgaas:
"Enumeration:
- Wait for device readiness after reset by polling Vendor ID and
looking for Configuration RRS instead of polling the Command
register and looking for non-error completions, to avoid hardware
retries done for RRS on non-Vendor ID reads (Bjorn Helgaas)
- Rename CRS Completion Status to RRS ('Request Retry Status') to
match PCIe r6.0 spec usage (Bjorn Helgaas)
- Clear LBMS bit after a manual link retrain so we don't try to
retrain a link when there's no downstream device anymore (Maciej W.
Rozycki)
- Revert to the original link speed after retraining fails instead of
leaving it restricted to 2.5GT/s, so a future device has a chance
to use higher speeds (Maciej W. Rozycki)
- Wait for each level of downstream bus, not just the first, to
become accessible before restoring devices on that bus (Ilpo
Järvinen)
- Add ARCH_PCI_DEV_GROUPS so s390 can add its own attribute_groups
without having to stomp on the core's pdev->dev.groups (Lukas
Wunner)
Driver binding:
- Export pcim_request_region(), a managed counterpart of
pci_request_region(), for use by drivers (Philipp Stanner)
- Export pcim_iomap_region() and deprecate pcim_iomap_regions()
(Philipp Stanner)
- Request the PCI BAR used by xboxvideo (Philipp Stanner)
- Request and map drm/ast BARs with pcim_iomap_region() (Philipp
Stanner)
MSI:
- Add MSI_FLAG_NO_AFFINITY flag for devices that mux MSIs onto a
single IRQ line and cannot set the affinity of each MSI to a
specific CPU core (Marek Vasut)
- Use MSI_FLAG_NO_AFFINITY and remove unnecessary .irq_set_affinity()
implementations in aardvark, altera, brcmstb, dwc, mediatek-gen3,
mediatek, mobiveil, plda, rcar, tegra, vmd, xilinx-nwl,
xilinx-xdma, and xilinx drivers to avoid 'IRQ: set affinity failed'
warnings (Marek Vasut)
Power management:
- Add pwrctl support for ATH11K inside the WCN6855 package (Konrad
Dybcio)
PCI device hotplug:
- Remove unnecessary hpc_ops struct from shpchp (ngn)
- Check for PCI_POSSIBLE_ERROR(), not 0xffffffff, in cpqphp
(weiyufeng)
Virtualization:
- Mark Creative Labs EMU20k2 INTx masking as broken (Alex Williamson)
- Add an ACS quirk for Qualcomm SA8775P, which doesn't advertise ACS
but does provide ACS-like features (Subramanian Ananthanarayanan)
IOMMU:
- Add function 0 DMA alias quirk for Glenfly Arise audio function,
which uses the function 0 Requester ID (WangYuli)
NPEM:
- Add Native PCIe Enclosure Management (NPEM) support for sysfs
control of NVMe RAID storage indicators (ok/fail/locate/
rebuild/etc) (Mariusz Tkaczyk)
- Add support for the ACPI _DSM PCIe SSD status LED management, which
is functionally similar to NPEM but mediated by platform firmware
(Mariusz Tkaczyk)
Device trees:
- Drop minItems and maxItems from ranges in PCI generic host binding
since host bridges may have several MMIO and I/O port apertures
(Frank Li)
- Add kirin, rcar-gen2, uniphier DT binding top-level constraints for
clocks (Krzysztof Kozlowski)
Altera PCIe controller driver:
- Convert altera DT bindings from text to YAML (Matthew Gerlach)
- Replace TLP_REQ_ID() with macro PCI_DEVID(), which does the same
thing and is what other drivers use (Jinjie Ruan)
Broadcom STB PCIe controller driver:
- Add DT binding maxItems for reset controllers (Jim Quinlan)
- Use the 'bridge' reset method if described in the DT (Jim Quinlan)
- Use the 'swinit' reset method if described in the DT (Jim Quinlan)
- Add 'has_phy' so the existence of a 'rescal' reset controller
doesn't imply software control of it (Jim Quinlan)
- Add support for many inbound DMA windows (Jim Quinlan)
- Rename SoC 'type' to 'soc_base' express the fact that SoCs come in
families of multiple similar devices (Jim Quinlan)
- Add Broadcom 7712 DT description and driver support (Jim Quinlan)
- Sort enums, pcie_offsets[], pcie_cfg_data, .compatible strings for
maintainability (Bjorn Helgaas)
Freescale i.MX6 PCIe controller driver:
- Add imx6q-pcie 'dbi2' and 'atu' reg-names for i.MX8M Endpoints
(Richard Zhu)
- Fix a code restructuring error that caused i.MX8MM and i.MX8MP
Endpoints to fail to establish link (Richard Zhu)
- Fix i.MX8MP Endpoint occasional failure to trigger MSI by enforcing
outbound alignment requirement (Richard Zhu)
- Call phy_power_off() in the .probe() error path (Frank Li)
- Rename internal names from imx6_* to imx_* since i.MX7/8/9 are also
supported (Frank Li)
- Manage Refclk by using SoC-specific callbacks instead of switch
statements (Frank Li)
- Manage core reset by using SoC-specific callbacks instead of switch
statements (Frank Li)
- Expand comments for erratum ERR010728 workaround (Frank Li)
- Use generic PHY APIs to configure mode, speed, and submode, which
is harmless for devices that implement their own internal PHY
management and don't set the generic imx_pcie->phy (Frank Li)
- Add i.MX8Q (i.MX8QM, i.MX8QXP, and i.MX8DXL) DT binding and driver
Root Complex support (Richard Zhu)
Freescale Layerscape PCIe controller driver:
- Replace layerscape-pcie DT binding compatible fsl,lx2160a-pcie with
fsl,lx2160ar2-pcie (Frank Li)
- Add layerscape-pcie DT binding deprecated 'num-viewport' property
to address a DT checker warning (Frank Li)
- Change layerscape-pcie DT binding 'fsl,pcie-scfg' to phandle-array
(Frank Li)
Loongson PCIe controller driver:
- Increase max PCI hosts to 8 for Loongson-3C6000 and newer chipsets
(Huacai Chen)
Marvell Aardvark PCIe controller driver:
- Fix issue with emulating Configuration RRS for two-byte reads of
Vendor ID; previously it only worked for four-byte reads (Bjorn
Helgaas)
MediaTek PCIe Gen3 controller driver:
- Add per-SoC struct mtk_gen3_pcie_pdata to support multiple SoC
types (Lorenzo Bianconi)
- Use reset_bulk APIs to manage PHY reset lines (Lorenzo Bianconi)
- Add DT and driver support for Airoha EN7581 PCIe controller
(Lorenzo Bianconi)
Qualcomm PCIe controller driver:
- Update qcom,pcie-sc7280 DT binding with eight interrupts (Rayyan
Ansari)
- Add back DT 'vddpe-3v3-supply', which was incorrectly removed
earlier (Johan Hovold)
- Drop endpoint redundant masking of global IRQ events (Manivannan
Sadhasivam)
- Clarify unknown global IRQ message and only log it once to avoid a
flood (Manivannan Sadhasivam)
- Add 'linux,pci-domain' property to endpoint DT binding (Manivannan
Sadhasivam)
- Assign PCI domain number for endpoint controllers (Manivannan
Sadhasivam)
- Add 'qcom_pcie_ep' and the PCI domain number to IRQ names for
endpoint controller (Manivannan Sadhasivam)
- Add global SPI interrupt for PCIe link events to DT binding
(Manivannan Sadhasivam)
- Add global RC interrupt handler to handle 'Link up' events and
automatically enumerate hot-added devices (Manivannan Sadhasivam)
- Avoid mirroring of DBI and iATU register space so it doesn't
overlap BAR MMIO space (Prudhvi Yarlagadda)
- Enable controller resources like PHY only after PERST# is
deasserted to partially avoid the problem that the endpoint SoC
crashes when accessing things when Refclk is absent (Manivannan
Sadhasivam)
- Add 16.0 GT/s equalization and RX lane margining settings (Shashank
Babu Chinta Venkata)
- Pass domain number to pci_bus_release_domain_nr() explicitly to
avoid a NULL pointer dereference (Manivannan Sadhasivam)
Renesas R-Car PCIe controller driver:
- Make the read-only const array 'check_addr' static (Colin Ian King)
- Add R-Car V4M (R8A779H0) PCIe host and endpoint to DT binding
(Yoshihiro Shimoda)
TI DRA7xx PCIe controller driver:
- Request IRQF_ONESHOT for 'dra7xx-pcie-main' IRQ since the primary
handler is NULL (Siddharth Vadapalli)
- Handle IRQ request errors during root port and endpoint probe
(Siddharth Vadapalli)
TI J721E PCIe driver:
- Add DT 'ti,syscon-acspcie-proxy-ctrl' and driver support to enable
the ACSPCIE module to drive Refclk for the Endpoint (Siddharth
Vadapalli)
- Extract the cadence link setup from cdns_pcie_host_setup() so link
setup can be done separately during resume (Thomas Richard)
- Add T_PERST_CLK_US definition for the mandatory delay between
Refclk becoming stable and PERST# being deasserted (Thomas Richard)
- Add j721e suspend and resume support (Théo Lebrun)
TI Keystone PCIe controller driver:
- Fix NULL pointer checking when applying MRRS limitation quirk for
AM65x SR 1.0 Errata #i2037 (Dan Carpenter)
Xilinx NWL PCIe controller driver:
- Fix off-by-one error in INTx IRQ handler that caused INTx
interrupts to be lost or delivered as the wrong interrupt (Sean
Anderson)
- Rate-limit misc interrupt messages (Sean Anderson)
- Turn off the clock on probe failure and device removal (Sean
Anderson)
- Add DT binding and driver support for enabling/disabling PHYs (Sean
Anderson)
- Add PCIe phy bindings for the ZCU102 (Sean Anderson)
Xilinx XDMA PCIe controller driver:
- Add support for Xilinx QDMA Soft IP PCIe Root Port Bridge to DT
binding and xilinx-dma-pl driver (Thippeswamy Havalige)
Miscellaneous:
- Fix buffer overflow in kirin_pcie_parse_port() (Alexandra Diupina)
- Fix minor kerneldoc issues and typos (Bjorn Helgaas)
- Use PCI_DEVID() macro in aer_inject() instead of open-coding it
(Jinjie Ruan)
- Check pcie_find_root_port() return in x86 fixups to avoid NULL
pointer dereferences (Samasth Norway Ananda)
- Make pci_bus_type constant (Kunwu Chan)
- Remove unused declarations of __pci_pme_wakeup() and
pci_vpd_release() (Yue Haibing)
- Remove any leftover .*.cmd files with make clean (zhang jiao)
- Remove unused BILLION macro (zhang jiao)"
* tag 'pci-v6.12-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci: (132 commits)
PCI: Fix typos
dt-bindings: PCI: qcom: Allow 'vddpe-3v3-supply' again
tools: PCI: Remove unused BILLION macro
tools: PCI: Remove .*.cmd files with make clean
PCI: Pass domain number to pci_bus_release_domain_nr() explicitly
PCI: dra7xx: Fix error handling when IRQ request fails in probe
PCI: dra7xx: Fix threaded IRQ request for "dra7xx-pcie-main" IRQ
PCI: qcom: Add RX lane margining settings for 16.0 GT/s
PCI: qcom: Add equalization settings for 16.0 GT/s
PCI: dwc: Always cache the maximum link speed value in dw_pcie::max_link_speed
PCI: dwc: Rename 'dw_pcie::link_gen' to 'dw_pcie::max_link_speed'
PCI: qcom-ep: Enable controller resources like PHY only after refclk is available
PCI: Mark Creative Labs EMU20k2 INTx masking as broken
dt-bindings: PCI: imx6q-pcie: Add reg-name "dbi2" and "atu" for i.MX8M PCIe Endpoint
dt-bindings: PCI: altera: msi: Convert to YAML
PCI: imx6: Add i.MX8Q PCIe Root Complex (RC) support
PCI: Rename CRS Completion Status to RRS
PCI: aardvark: Correct Configuration RRS checking
PCI: Wait for device readiness with Configuration RRS
PCI: brcmstb: Sort enums, pcie_offsets[], pcie_cfg_data, .compatible strings
...
As discussed during the distro-centric session within the sched_ext
Microconference at LPC 2024, introduce a sequence counter that is
incremented every time a BPF scheduler is loaded.
This feature can help distributions in diagnosing potential performance
regressions by identifying systems where users are running (or have ran)
custom BPF schedulers.
Example:
arighi@virtme-ng~> cat /sys/kernel/sched_ext/enable_seq
0
arighi@virtme-ng~> sudo scx_simple
local=1 global=0
^CEXIT: unregistered from user space
arighi@virtme-ng~> cat /sys/kernel/sched_ext/enable_seq
1
In this way user-space tools (such as Ubuntu's apport and similar) are
able to gather and include this information in bug reports.
Cc: Giovanni Gherdovich <giovanni.gherdovich@suse.com>
Cc: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
Cc: Marcelo Henrique Cerri <marcelo.cerri@canonical.com>
Cc: Phil Auld <pauld@redhat.com>
Signed-off-by: Andrea Righi <andrea.righi@linux.dev>
Signed-off-by: Tejun Heo <tj@kernel.org>
a2f4b16e73 ("sched_ext: Build fix on !CONFIG_STACKTRACE[_SUPPORT]") tried
fixing build when !CONFIG_STACKTRACE but didn't so fully. Also put
stack_trace_print() and stack_trace_save() inside CONFIG_STACKTRACE to fix
build when !CONFIG_STACKTRACE.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202409220642.fDW2OmWc-lkp@intel.com/
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Merge tag 'pull-stable-struct_fd' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull 'struct fd' updates from Al Viro:
"Just the 'struct fd' layout change, with conversion to accessor
helpers"
* tag 'pull-stable-struct_fd' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
add struct fd constructors, get rid of __to_fd()
struct fd: representation change
introduce fd_file(), convert all accessors to it.
Puranjay Mohan