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Linux kernel
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the problems which may result by upgrading your kernel.
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Pull irq fixes from Borislav Petkov:
- Restore the original buslock locking in a couple of places in the irq
core subsystem after a rework
* tag 'irq_urgent_for_v6.18_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
genirq/manage: Add buslock back in to enable_irq()
genirq/manage: Add buslock back in to __disable_irq_nosync()
genirq/chip: Add buslock back in to irq_set_handler()
Pull objtool fixes from Borislav Petkov:
- Fix x32 build due to wrong format specifier on that sub-arch
- Add one more Rust noreturn function to objtool's list
* tag 'objtool_urgent_for_v6.18_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
objtool: Fix failure when being compiled on x32 system
objtool/rust: add one more `noreturn` Rust function
The locking was changed from a buslock to a plain lock, but the patch
description states there was no functional change. Assuming this was
accidental so reverting to using the buslock.
Fixes: bddd10c55407 ("genirq/manage: Rework enable_irq()")
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://patch.msgid.link/20251023154901.1333755-4-ckeepax@opensource.cirrus.com
Pull scheduler fix from Borislav Petkov:
- Make sure a CFS runqueue on a throttled hierarchy has its PELT clock
throttled otherwise task movement and manipulation would lead to
dangling cfs_rq references and an eventual crash
* tag 'sched_urgent_for_v6.18_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/fair: Start a cfs_rq on throttled hierarchy with PELT clock throttled
Fix compilation failure when compiling the kernel with the x32 toolchain.
In file included from check.c:16:
check.c: In function ¡check_abs_references¢:
/usr/src/git/linux-2.6/tools/objtool/include/objtool/warn.h:47:17: error: format ¡%lx¢ expects argument of type ¡long unsigned int¢, but argument 7 has type ¡u64¢ {aka ¡long
long unsigned int¢} [-Werror=format=]
47 | "%s%s%s: objtool" extra ": " format "\n", \
| ^~~~~~~~~~~~~~~~~
/usr/src/git/linux-2.6/tools/objtool/include/objtool/warn.h:54:9: note: in expansion of macro ¡___WARN¢
54 | ___WARN(severity, "", format, ##__VA_ARGS__)
| ^~~~~~~
/usr/src/git/linux-2.6/tools/objtool/include/objtool/warn.h:74:27: note: in expansion of macro ¡__WARN¢
74 | #define WARN(format, ...) __WARN(WARN_STR, format, ##__VA_ARGS__)
| ^~~~~~
check.c:4713:33: note: in expansion of macro ¡WARN¢
4713 | WARN("section %s has absolute relocation at offset 0x%lx",
| ^~~~
Fixes: 0d6e4563fc03 ("objtool: Add action to check for absence of absolute relocations")
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://patch.msgid.link/1ac32fff-2e67-5155-f570-69aad5bf5412@redhat.com
The locking was changed from a buslock to a plain lock, but the patch
description states there was no functional change. Assuming this was
accidental so reverting to using the buslock.
Fixes: 1b7444446724 ("genirq/manage: Rework __disable_irq_nosync()")
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://patch.msgid.link/20251023154901.1333755-3-ckeepax@opensource.cirrus.com
Pull timer fix from Borislav Petkov:
- Do not create more than eight (max supported) AUX clocks sysfs
hierarchies
* tag 'timers_urgent_for_v6.18_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
timekeeping: Fix aux clocks sysfs initialization loop bound
Matteo reported hitting the assert_list_leaf_cfs_rq() warning from
enqueue_task_fair() post commit fe8d238e646e ("sched/fair: Propagate
load for throttled cfs_rq") which transitioned to using
cfs_rq_pelt_clock_throttled() check for leaf cfs_rq insertions in
propagate_entity_cfs_rq().
The "cfs_rq->pelt_clock_throttled" flag is used to indicate if the
hierarchy has its PELT frozen. If a cfs_rq's PELT is marked frozen, all
its descendants should have their PELT frozen too or weird things can
happen as a result of children accumulating PELT signals when the
parents have their PELT clock stopped.
Another side effect of this is the loss of integrity of the leaf cfs_rq
list. As debugged by Aaron, consider the following hierarchy:
root(#)
/ \
A(#) B(*)
|
C <--- new cgroup
|
D <--- new cgroup
# - Already on leaf cfs_rq list
* - Throttled with PELT frozen
The newly created cgroups don't have their "pelt_clock_throttled" signal
synced with cgroup B. Next, the following series of events occur:
1. online_fair_sched_group() for cgroup D will call
propagate_entity_cfs_rq(). (Same can happen if a throttled task is
moved to cgroup C and enqueue_task_fair() returns early.)
propagate_entity_cfs_rq() adds the cfs_rq of cgroup C to
"rq->tmp_alone_branch" since its PELT clock is not marked throttled
and cfs_rq of cgroup B is not on the list.
cfs_rq of cgroup B is skipped since its PELT is throttled.
root cfs_rq already exists on cfs_rq leading to
list_add_leaf_cfs_rq() returning early.
The cfs_rq of cgroup C is left dangling on the
"rq->tmp_alone_branch".
2. A new task wakes up on cgroup A. Since the whole hierarchy is already
on the leaf cfs_rq list, list_add_leaf_cfs_rq() keeps returning early
without any modifications to "rq->tmp_alone_branch".
The final assert_list_leaf_cfs_rq() in enqueue_task_fair() sees the
dangling reference to cgroup C's cfs_rq in "rq->tmp_alone_branch".
!!! Splat !!!
Syncing the "pelt_clock_throttled" indicator with parent cfs_rq is not
enough since the new cfs_rq is not yet enqueued on the hierarchy. A
dequeue on other subtree on the throttled hierarchy can freeze the PELT
clock for the parent hierarchy without setting the indicators for this
newly added cfs_rq which was never enqueued.
Since there are no tasks on the new hierarchy, start a cfs_rq on a
throttled hierarchy with its PELT clock throttled. The first enqueue, or
the distribution (whichever happens first) will unfreeze the PELT clock
and queue the cfs_rq on the leaf cfs_rq list.
While at it, add an assert_list_leaf_cfs_rq() in
propagate_entity_cfs_rq() to catch such cases in the future.
Closes: https://lore.kernel.org/lkml/58a587d694f33c2ea487c700b0d046fa@codethink.co.uk/
Fixes: e1fad12dcb66 ("sched/fair: Switch to task based throttle model")
Reported-by: Matteo Martelli <matteo.martelli@codethink.co.uk>
Suggested-by: Aaron Lu <ziqianlu@bytedance.com>
Signed-off-by: K Prateek Nayak <kprateek.nayak@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Aaron Lu <ziqianlu@bytedance.com>
Tested-by: Aaron Lu <ziqianlu@bytedance.com>
Tested-by: Matteo Martelli <matteo.martelli@codethink.co.uk>
Link: https://patch.msgid.link/20251021053522.37583-1-kprateek.nayak@amd.com
Between Rust 1.79 and 1.86, under `CONFIG_RUST_KERNEL_DOCTESTS=y`,
`objtool` may report:
rust/doctests_kernel_generated.o: warning: objtool:
rust_doctest_kernel_alloc_kbox_rs_13() falls through to next
function rust_doctest_kernel_alloc_kvec_rs_0()
(as well as in rust_doctest_kernel_alloc_kvec_rs_0) due to calls to the
`noreturn` symbol:
core::option::expect_failed
from code added in commits 779db37373a3 ("rust: alloc: kvec: implement
AsPageIter for VVec") and 671618432f46 ("rust: alloc: kbox: implement
AsPageIter for VBox").
Thus add the mangled one to the list so that `objtool` knows it is
actually `noreturn`.
This can be reproduced as well in other versions by tweaking the code,
such as the latest stable Rust (1.90.0).
Stable does not have code that triggers this, but it could have it in
the future. Downstream forks could too. Thus tag it for backport.
See commit 56d680dd23c3 ("objtool/rust: list `noreturn` Rust functions")
for more details.
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Cc: stable@vger.kernel.org # Needed in 6.12.y and later.
Link: https://patch.msgid.link/20251020020714.2511718-1-ojeda@kernel.org
The locking was changed from a buslock to a plain lock, but the patch
description states there was no functional change. Assuming this was
accidental so reverting to using the buslock.
Fixes: 5cd05f3e2315 ("genirq/chip: Rework irq_set_handler() variants")
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://patch.msgid.link/20251023154901.1333755-2-ckeepax@opensource.cirrus.com
Pull driver core fixes from Danilo Krummrich:
- In Device::parent(), do not make any assumptions on the device
context of the parent device
- Check visibility before changing ownership of a sysfs attribute
group
- In topology_parse_cpu_capacity(), replace an incorrect usage of
PTR_ERR_OR_ZERO() with IS_ERR_OR_NULL()
- In devcoredump, fix a circular locking dependency between
struct devcd_entry::mutex and kernfs
- Do not warn about a pending fw_devlink sync state
* tag 'driver-core-6.18-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core:
arch_topology: Fix incorrect error check in topology_parse_cpu_capacity()
rust: device: fix device context of Device::parent()
sysfs: check visibility before changing group attribute ownership
devcoredump: Fix circular locking dependency with devcd->mutex.
driver core: fw_devlink: Don't warn about sync_state() pending
The loop in tk_aux_sysfs_init() uses `i <= MAX_AUX_CLOCKS` as the
termination condition, which results in 9 iterations (i=0 to 8) when
MAX_AUX_CLOCKS is defined as 8. However, the kernel is designed to support
only up to 8 auxiliary clocks.
This off-by-one error causes the creation of a 9th sysfs entry that exceeds
the intended auxiliary clock range.
Fix the loop bound to use `i < MAX_AUX_CLOCKS` to ensure exactly 8
auxiliary clock entries are created, matching the design specification.
Fixes: 7b95663a3d96 ("timekeeping: Provide interface to control auxiliary clocks")
Signed-off-by: Haofeng Li <lihaofeng@kylinos.cn>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://patch.msgid.link/tencent_2376993D9FC06A3616A4F981B3DE1C599607@qq.com
Pull firewire fixes from Takashi Sakamoto:
"A small collection of FireWire fixes. This includes corrections to
sparse and API documentation"
* tag 'firewire-fixes-6.18-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394:
firewire: init_ohci1394_dma: add missing function parameter documentation
firewire: core: fix __must_hold() annotation
Fix incorrect use of PTR_ERR_OR_ZERO() in topology_parse_cpu_capacity()
which causes the code to proceed with NULL clock pointers. The current
logic uses !PTR_ERR_OR_ZERO(cpu_clk) which evaluates to true for both
valid pointers and NULL, leading to potential NULL pointer dereference
in clk_get_rate().
Per include/linux/err.h documentation, PTR_ERR_OR_ZERO(ptr) returns:
"The error code within @ptr if it is an error pointer; 0 otherwise."
This means PTR_ERR_OR_ZERO() returns 0 for both valid pointers AND NULL
pointers. Therefore !PTR_ERR_OR_ZERO(cpu_clk) evaluates to true (proceed)
when cpu_clk is either valid or NULL, causing clk_get_rate(NULL) to be
called when of_clk_get() returns NULL.
Replace with !IS_ERR_OR_NULL(cpu_clk) which only proceeds for valid
pointers, preventing potential NULL pointer dereference in clk_get_rate().
Cc: stable <stable@kernel.org>
Signed-off-by: Kaushlendra Kumar <kaushlendra.kumar@intel.com>
Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Fixes: b8fe128dad8f ("arch_topology: Adjust initial CPU capacities with current freq")
Link: https://patch.msgid.link/20250923174308.1771906-1-kaushlendra.kumar@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull scheduler fixes from Borislav Petkov:
- Make sure the check for lost pelt idle time is done unconditionally
to have correct lost idle time accounting
- Stop the deadline server task before a CPU goes offline
* tag 'sched_urgent_for_v6.18_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/fair: Fix pelt lost idle time detection
sched/deadline: Stop dl_server before CPU goes offline
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