| Age | Commit message (Collapse) | Author | Files | Lines |
|---|
|
When updating paravirtual clocks, setup the Hyper-V TSC page before
Xen PV clocks. This will allow dropping xen_pvclock_tsc_unstable in favor
of simply clearing PVCLOCK_TSC_STABLE_BIT in the reference flags.
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: Paul Durrant <paul@xen.org>
Link: https://lore.kernel.org/r/20250201013827.680235-11-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
|
|
Remove the per-vCPU "cache" of the reference pvclock and instead cache
only the TSC shift+multiplier. All other fields in pvclock are fully
recomputed by kvm_guest_time_update(), i.e. aren't actually persisted.
In addition to shaving a few bytes, explicitly tracking the TSC shift/mul
fields makes it easier to see that those fields are tied to hw_tsc_khz
(they exist to avoid having to do expensive math in the common case).
And conversely, not tracking the other fields makes it easier to see that
things like the version number are pulled from the guest's copy, not from
KVM's reference.
Reviewed-by: Paul Durrant <paul@xen.org>
Link: https://lore.kernel.org/r/20250201013827.680235-10-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
|
|
Pass the reference pvclock structure that's used to setup each individual
pvclock as a parameter to kvm_setup_guest_pvclock() as a preparatory step
toward removing kvm_vcpu_arch.hv_clock.
No functional change intended.
Reviewed-by: Paul Durrant <paul@xen.org>
Link: https://lore.kernel.org/r/20250201013827.680235-9-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
|
|
Handle "guest stopped" propagation only for kvmclock, as the flag is set
if and only if kvmclock is "active", i.e. can only be set for Xen PV clock
if kvmclock *and* Xen PV clock are in-use by the guest, which creates very
bizarre behavior for the guest.
Simply restrict the flag to kvmclock, e.g. instead of trying to handle
Xen PV clock, as propagation of PVCLOCK_GUEST_STOPPED was unintentionally
added during a refactoring, and while Xen proper defines
XEN_PVCLOCK_GUEST_STOPPED, there's no evidence that Xen guests actually
support the flag.
Check and clear pvclock_set_guest_stopped_request if and only if kvmclock
is active to preserve the original behavior, i.e. keep the flag pending
if kvmclock happens to be disabled when KVM processes the initial request.
Fixes: aa096aa0a05f ("KVM: x86/xen: setup pvclock updates")
Cc: Paul Durrant <pdurrant@amazon.com>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Paul Durrant <paul@xen.org>
Link: https://lore.kernel.org/r/20250201013827.680235-8-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
|
|
When updating a specific PV clock, make a full copy of KVM's reference
copy/cache so that PVCLOCK_GUEST_STOPPED doesn't bleed across clocks.
E.g. in the unlikely scenario the guest has enabled both kvmclock and Xen
PV clock, a dangling GUEST_STOPPED in kvmclock would bleed into Xen PV
clock.
Using a local copy of the pvclock structure also sets the stage for
eliminating the per-vCPU copy/cache (only the TSC frequency information
actually "needs" to be cached/persisted).
Fixes: aa096aa0a05f ("KVM: x86/xen: setup pvclock updates")
Reviewed-by: Paul Durrant <paul@xen.org>
Link: https://lore.kernel.org/r/20250201013827.680235-7-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
|
|
Use the guest's copy of its pvclock when starting a Xen timer, as KVM's
reference copy may not be up-to-date, i.e. may yield a false positive of
sorts. In the unlikely scenario that the guest is starting a Xen timer
and has used a Xen pvclock in the past, but has since but turned it "off",
then vcpu->arch.hv_clock may be stale, as KVM's reference copy is updated
if and only if at least one pvclock is enabled.
Furthermore, vcpu->arch.hv_clock is currently used by three different
pvclocks: kvmclock, Xen, and Xen compat. While it's extremely unlikely a
guest would ever enable multiple pvclocks, effectively sharing KVM's
reference clock could yield very weird behavior. Using the guest's active
Xen pvclock instead of KVM's reference will allow dropping KVM's
reference copy.
Fixes: 451a707813ae ("KVM: x86/xen: improve accuracy of Xen timers")
Cc: Paul Durrant <pdurrant@amazon.com>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Paul Durrant <paul@xen.org>
Link: https://lore.kernel.org/r/20250201013827.680235-6-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
|
|
Handle "guest stopped" requests once per guest time update in preparation
of restoring KVM's historical behavior of setting PVCLOCK_GUEST_STOPPED
for kvmclock and only kvmclock. For now, simply move the code to minimize
the probability of an unintentional change in functionally.
Note, in practice, all clocks are guaranteed to see the request (or not)
even though each PV clock processes the request individual, as KVM holds
vcpu->mutex (blocks KVM_KVMCLOCK_CTRL) and it should be impossible for
KVM's suspend notifier to run while KVM is handling requests. And because
the helper updates the reference flags, all subsequent PV clock updates
will pick up PVCLOCK_GUEST_STOPPED.
Note #2, once PVCLOCK_GUEST_STOPPED is restricted to kvmclock, the
horrific #ifdef will go away.
Cc: Paul Durrant <pdurrant@amazon.com>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Paul Durrant <paul@xen.org>
Link: https://lore.kernel.org/r/20250201013827.680235-5-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
|
|
Drop the local pvclock_flags in kvm_guest_time_update(), the local variable
is immediately shoved into the per-vCPU "cache", i.e. the local variable
serves no purpose.
No functional change intended.
Reviewed-by: Paul Durrant <paul@xen.org>
Link: https://lore.kernel.org/r/20250201013827.680235-4-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
|
|
Drop KVM's handling of kvm_set_guest_paused() failure when reacting to a
SUSPEND notification, as kvm_set_guest_paused() only "fails" if the vCPU
isn't using kvmclock, and KVM's notifier callback pre-checks that kvmclock
is active. I.e. barring some bizarre edge case that shouldn't be treated
as an error in the first place, kvm_arch_suspend_notifier() can't fail.
Reviewed-by: Paul Durrant <paul@xen.org>
Link: https://lore.kernel.org/r/20250201013827.680235-3-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
|
|
When queueing vCPU PVCLOCK updates in response to SUSPEND or HIBERNATE,
don't take kvm->lock as doing so can trigger a largely theoretical
deadlock, it is perfectly safe to iterate over the xarray of vCPUs without
holding kvm->lock, and kvm->lock doesn't protect kvm_set_guest_paused() in
any way (pv_time.active and pvclock_set_guest_stopped_request are
protected by vcpu->mutex, not kvm->lock).
Reported-by: syzbot+352e553a86e0d75f5120@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/677c0f36.050a0220.3b3668.0014.GAE@google.com
Fixes: 7d62874f69d7 ("kvm: x86: implement KVM PM-notifier")
Reviewed-by: Paul Durrant <paul@xen.org>
Link: https://lore.kernel.org/r/20250201013827.680235-2-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
|
|
|
|
Commit 3775fc538f53 ("PM: sleep: core: Synchronize runtime PM status of
parents and children") exposed an issue related to simple_pm_bus_pm_ops
that uses pm_runtime_force_suspend() and pm_runtime_force_resume() as
bus type PM callbacks for the noirq phases of system-wide suspend and
resume.
The problem is that pm_runtime_force_suspend() does not distinguish
runtime-suspended devices from devices for which runtime PM has never
been enabled, so if it sees a device with runtime PM status set to
RPM_ACTIVE, it will assume that runtime PM is enabled for that device
and so it will attempt to suspend it with the help of its runtime PM
callbacks which may not be ready for that. As it turns out, this
causes simple_pm_bus_runtime_suspend() to crash due to a NULL pointer
dereference.
Another problem related to the above commit and simple_pm_bus_pm_ops is
that setting runtime PM status of a device handled by the latter to
RPM_ACTIVE will actually prevent it from being resumed because
pm_runtime_force_resume() only resumes devices with runtime PM status
set to RPM_SUSPENDED.
To mitigate these issues, do not allow power.set_active to propagate
beyond the parent of the device with DPM_FLAG_SMART_SUSPEND set that
will need to be resumed, which should be a sufficient stop-gap for the
time being, but they will need to be properly addressed in the future
because in general during system-wide resume it is necessary to resume
all devices in a dependency chain in which at least one device is going
to be resumed.
Fixes: 3775fc538f53 ("PM: sleep: core: Synchronize runtime PM status of parents and children")
Closes: https://lore.kernel.org/linux-pm/1c2433d4-7e0f-4395-b841-b8eac7c25651@nvidia.com/
Reported-by: Jon Hunter <jonathanh@nvidia.com>
Tested-by: Johan Hovold <johan+linaro@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://patch.msgid.link/6137505.lOV4Wx5bFT@rjwysocki.net
|
|
The code was restructured where the function graph notrace code, that
would not trace a function and all its children is done by setting a
NOTRACE flag when the function that is not to be traced is hit.
There's a TRACE_GRAPH_NOTRACE_BIT which defines the bit in the flags and a
TRACE_GRAPH_NOTRACE which is the mask with that bit set. But the
restructuring used TRACE_GRAPH_NOTRACE_BIT when it should have used
TRACE_GRAPH_NOTRACE.
For example:
# cd /sys/kernel/tracing
# echo set_track_prepare stack_trace_save > set_graph_notrace
# echo function_graph > current_tracer
# cat trace
[..]
0) | __slab_free() {
0) | free_to_partial_list() {
0) | arch_stack_walk() {
0) | __unwind_start() {
0) 0.501 us | get_stack_info();
Where a non filter trace looks like:
# echo > set_graph_notrace
# cat trace
0) | free_to_partial_list() {
0) | set_track_prepare() {
0) | stack_trace_save() {
0) | arch_stack_walk() {
0) | __unwind_start() {
Where the filter should look like:
# cat trace
0) | free_to_partial_list() {
0) | _raw_spin_lock_irqsave() {
0) 0.350 us | preempt_count_add();
0) 0.351 us | do_raw_spin_lock();
0) 2.440 us | }
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250208001511.535be150@batman.local.home
Fixes: b84214890a9bc ("function_graph: Move graph notrace bit to shadow stack global var")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
|
|
-Wenum-enum-conversion was strengthened in clang-19 to warn for C, which
caused the kernel to move it to W=1 in commit 75b5ab134bb5 ("kbuild:
Move -Wenum-{compare-conditional,enum-conversion} into W=1") because
there were numerous instances that would break builds with -Werror.
Unfortunately, this is not a full solution, as more and more developers,
subsystems, and distributors are building with W=1 as well, so they
continue to see the numerous instances of this warning.
Since the move to W=1, there have not been many new instances that have
appeared through various build reports and the ones that have appeared
seem to be following similar existing patterns, suggesting that most
instances of this warning will not be real issues. The only alternatives
for silencing this warning are adding casts (which is generally seen as
an ugly practice) or refactoring the enums to macro defines or a unified
enum (which may be undesirable because of type safety in other parts of
the code).
Move the warning to W=2, where warnings that occur frequently but may be
relevant should reside.
Cc: stable@vger.kernel.org
Fixes: 75b5ab134bb5 ("kbuild: Move -Wenum-{compare-conditional,enum-conversion} into W=1")
Link: https://lore.kernel.org/ZwRA9SOcOjjLJcpi@google.com/
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
While attempting to build a Debian packages with CC="ccache gcc", I
saw the following error as builddeb builds linux-headers-$KERNELVERSION:
make HOSTCC=ccache gcc VPATH= srcroot=. -f ./scripts/Makefile.build obj=debian/linux-headers-6.14.0-rc1/usr/src/linux-headers-6.14.0-rc1/scripts
make[6]: *** No rule to make target 'gcc'. Stop.
Upon investigation, it seems that one instance of $(CC) variable reference
in ./scripts/package/install-extmod-build was missing quotation marks,
causing the above error.
Add the missing quotation marks around $(CC) to fix build.
Fixes: 5f73e7d0386d ("kbuild: refactor cross-compiling linux-headers package")
Co-developed-by: Mingcong Bai <jeffbai@aosc.io>
Signed-off-by: Mingcong Bai <jeffbai@aosc.io>
Tested-by: WangYuli <wangyuli@uniontech.com>
Signed-off-by: WangYuli <wangyuli@uniontech.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
|
|
I no longer have any faith left in the kernel development process or
community management approach.
Apple/ARM platform development will continue downstream. If I feel like
sending some patches upstream in the future myself for whatever subtree
I may, or I may not. Anyone who feels like fighting the upstreaming
fight themselves is welcome to do so.
Signed-off-by: Hector Martin <marcan@marcan.st>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
I need to filter my emails better, switch to pavel@kernel.org address
to help with that.
Signed-off-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
This costs a strlen() call when instatianating a symlink.
Preferably it would be hidden behind VFS_WARN_ON (or compatible), but
there is no such facility at the moment. With the facility in place the
call can be patched out in production kernels.
In the meantime, since the cost is being paid unconditionally, use the
result to a fixup the bad caller.
This is not expected to persist in the long run (tm).
Sample splat:
bad length passed for symlink [/tmp/syz-imagegen43743633/file0/file0] (got 131109, expected 37)
[rest of WARN blurp goes here]
Signed-off-by: Mateusz Guzik <mjguzik@gmail.com>
Link: https://lore.kernel.org/r/20250204213207.337980-1-mjguzik@gmail.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
|
|
Pidfs supports extensible and non-extensible ioctls. The extensible
ioctls need to check for the ioctl number itself not just the ioctl
command otherwise both backward- and forward compatibility are broken.
The pidfs ioctl handler also needs to look at the type of the ioctl
command to guard against cases where "[...] a daemon receives some
random file descriptor from a (potentially less privileged) client and
expects the FD to be of some specific type, it might call ioctl() on
this FD with some type-specific command and expect the call to fail if
the FD is of the wrong type; but due to the missing type check, the
kernel instead performs some action that userspace didn't expect."
(cf. [1]]
Link: https://lore.kernel.org/r/20250204-work-pidfs-ioctl-v1-1-04987d239575@kernel.org
Link: https://lore.kernel.org/r/CAG48ez2K9A5GwtgqO31u9ZL292we8ZwAA=TJwwEv7wRuJ3j4Lw@mail.gmail.com [1]
Fixes: 8ce352818820 ("pidfs: check for valid ioctl commands")
Acked-by: Luca Boccassi <luca.boccassi@gmail.com>
Reported-by: Jann Horn <jannh@google.com>
Cc: stable@vger.kernel.org # v6.13; please backport with 8ce352818820 ("pidfs: check for valid ioctl commands")
Signed-off-by: Christian Brauner <brauner@kernel.org>
|
|
After introducing pre-content events, we had a regression related to
disabling huge faults on files that should never have pre-content events
enabled.
This happened because the default f_mode of allocated files (0) does
not disable pre-content events.
Pre-content events are disabled in file_set_fsnotify_mode_by_watchers()
but internal files may not get to call this helper.
Initialize f_mode to disable permission and pre-content events for all
files and if needed they will be enabled for the callers of
file_set_fsnotify_mode_by_watchers().
Fixes: 20bf82a898b6 ("mm: don't allow huge faults for files with pre content watches")
Reported-by: Alex Williamson <alex.williamson@redhat.com>
Closes: https://lore.kernel.org/linux-fsdevel/20250131121703.1e4d00a7.alex.williamson@redhat.com/
Tested-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Link: https://lore.kernel.org/r/20250203223205.861346-4-amir73il@gmail.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
|
|
STATMOUNT_MNT_OPTS can actually be missing if there are no options. This
is a change of behavior since 75ead69a7173 ("fs: don't let statmount return
empty strings").
The other checks shouldn't actually trigger, but add them for correctness
and for easier debugging if the test fails.
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Link: https://lore.kernel.org/r/20250129160641.35485-1-mszeredi@redhat.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
|
|
Most pseudo files are not applicable for fsnotify events at all,
let alone to the new pre-content events.
Disable notifications to all files allocated with alloc_file_pseudo()
and enable legacy inotify events for the specific cases of pipe and
socket, which have known users of inotify events.
Pre-content events are also kept disabled for sockets and pipes.
Fixes: 20bf82a898b6 ("mm: don't allow huge faults for files with pre content watches")
Reported-by: Alex Williamson <alex.williamson@redhat.com>
Closes: https://lore.kernel.org/linux-fsdevel/20250131121703.1e4d00a7.alex.williamson@redhat.com/
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/linux-fsdevel/CAHk-=wi2pThSVY=zhO=ZKxViBj5QCRX-=AS2+rVknQgJnHXDFg@mail.gmail.com/
Tested-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Link: https://lore.kernel.org/r/20250203223205.861346-3-amir73il@gmail.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
|
|
Prepending security options was made conditional on sb->s_op->show_options,
but security options are independent of sb options.
Fixes: 056d33137bf9 ("fs: prepend statmount.mnt_opts string with security_sb_mnt_opts()")
Fixes: f9af549d1fd3 ("fs: export mount options via statmount()")
Cc: stable@vger.kernel.org # v6.11
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Link: https://lore.kernel.org/r/20250129151253.33241-1-mszeredi@redhat.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
|
|
The FMODE_NONOTIFY_* bits are a 2-bits mode. Open coding manipulation
of those bits is risky. Use an accessor file_set_fsnotify_mode() to
set the mode.
Rename file_set_fsnotify_mode() => file_set_fsnotify_mode_from_watchers()
to make way for the simple accessor name.
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Link: https://lore.kernel.org/r/20250203223205.861346-2-amir73il@gmail.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
|
|
All users of lockref_init() now initialize the count to 1, so hardcode
that and remove the count argument.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Link: https://lore.kernel.org/r/20250130135624.1899988-4-agruenba@redhat.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
|
|
In qd_alloc(), initialize the lockref count to 1 to cover the common
case. Compensate for that in gfs2_quota_init() by adjusting the count
back down to 0; this only occurs when mounting the filesystem rw.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Link: https://lore.kernel.org/r/20250130135624.1899988-3-agruenba@redhat.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
|
|
Move the initialization of gl_lockref from gfs2_init_glock_once() to
gfs2_glock_get(). This allows to use lockref_init() there.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Link: https://lore.kernel.org/r/20250130135624.1899988-2-agruenba@redhat.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
|
|
Just like it's normal for unset values to be zero, unset strings should be
empty instead of containing random values.
It seems to be a typical mistake that the mask returned by statmount is not
checked, which can result in various bugs.
With this fix, these bugs are prevented, since it is highly likely that
userspace would just want to turn the missing mask case into an empty
string anyway (most of the recently found cases are of this type).
Link: https://lore.kernel.org/all/CAJfpegsVCPfCn2DpM8iiYSS5DpMsLB8QBUCHecoj6s0Vxf4jzg@mail.gmail.com/
Fixes: 68385d77c05b ("statmount: simplify string option retrieval")
Fixes: 46eae99ef733 ("add statmount(2) syscall")
Cc: stable@vger.kernel.org # v6.8
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Link: https://lore.kernel.org/r/20250130121500.113446-1-mszeredi@redhat.com
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
|
|
Building with GCC 15 results in build error
fs/vboxsf/super.c:24:54: error: initializer-string for array of ‘unsigned char’ is too long [-Werror=unterminated-string-initialization]
24 | static const unsigned char VBSF_MOUNT_SIGNATURE[4] = "\000\377\376\375";
| ^~~~~~~~~~~~~~~~~~
cc1: all warnings being treated as errors
Due to GCC having enabled -Werror=unterminated-string-initialization[0]
by default. Separately initializing each array element of
VBSF_MOUNT_SIGNATURE to ensure NUL termination, thus satisfying GCC 15
and fixing the build error.
[0]: https://gcc.gnu.org/onlinedocs/gcc/Warning-Options.html#index-Wno-unterminated-string-initialization
Signed-off-by: Brahmajit Das <brahmajit.xyz@gmail.com>
Link: https://lore.kernel.org/r/20250121162648.1408743-1-brahmajit.xyz@gmail.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
|
|
Clang static checker(scan-build) warning:
fs/stat.c:287:21: warning: The left expression of the compound assignment is
an uninitialized value. The computed value will also be garbage.
287 | stat->result_mask |= STATX_MNT_ID_UNIQUE;
| ~~~~~~~~~~~~~~~~~ ^
fs/stat.c:290:21: warning: The left expression of the compound assignment is
an uninitialized value. The computed value will also be garbage.
290 | stat->result_mask |= STATX_MNT_ID;
When vfs_getattr() failed because of security_inode_getattr(), 'stat' is
uninitialized. In this case, there is a harmless garbage problem in
vfs_statx_path(). It's better to return error directly when
vfs_getattr() failed, avoiding garbage value and more clearly.
Signed-off-by: Su Hui <suhui@nfschina.com>
Link: https://lore.kernel.org/r/20250119025946.1168957-1-suhui@nfschina.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
|
|
Before attaching a new root to the old root, the children counter of the
new root is checked to verify that only the upcoming CPU's top group have
been connected to it. However since the recently added commit b729cc1ec21a
("timers/migration: Fix another race between hotplug and idle entry/exit")
this check is not valid anymore because the old root is pre-accounted
as a child to the new root. Therefore after connecting the upcoming
CPU's top group to the new root, the children count to be expected must
be 2 and not 1 anymore.
This omission results in the old root to not be connected to the new
root. Then eventually the system may run with more than one top level,
which defeats the purpose of a single idle migrator.
Also the old root is pre-accounted but not connected upon the new root
creation. But it can be connected to the new root later on. Therefore
the old root may be accounted twice to the new root. The propagation of
such overcommit can end up creating a double final top-level root with a
groupmask incorrectly initialized. Although harmless given that the final
top level roots will never have a parent to walk up to, this oddity
opportunistically reported the core issue:
WARNING: CPU: 8 PID: 0 at kernel/time/timer_migration.c:543 tmigr_requires_handle_remote
CPU: 8 UID: 0 PID: 0 Comm: swapper/8
RIP: 0010:tmigr_requires_handle_remote
Call Trace:
<IRQ>
? tmigr_requires_handle_remote
? hrtimer_run_queues
update_process_times
tick_periodic
tick_handle_periodic
__sysvec_apic_timer_interrupt
sysvec_apic_timer_interrupt
</IRQ>
Fix the problem by taking the old root into account in the children count
of the new root so the connection is not omitted.
Also warn when more than one top level group exists to better detect
similar issues in the future.
Fixes: b729cc1ec21a ("timers/migration: Fix another race between hotplug and idle entry/exit")
Reported-by: Matt Fleming <mfleming@cloudflare.com>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/all/20250205160220.39467-1-frederic@kernel.org
|
|
The space separator was factored out from the multiple chip name prints,
but several irq_chip::irq_print_chip() callbacks still print a leading
space. Remove the superfluous double spaces.
Fixes: 9d9f204bdf7243bf ("genirq/proc: Add missing space separator back")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/893f7e9646d8933cd6786d5a1ef3eb076d263768.1738764803.git.geert+renesas@glider.be
|
|
Previously, bch2_bkey_sectors_need_rebalance() called
bch2_target_accepts_data(), checking whether the target is writable.
However, this means that adding or removing devices from a target would
change the value of bch2_bkey_sectors_need_rebalance() for an existing
extent; this needs to be invariant so that the extent trigger can
correctly maintain rebalance_work accounting.
Instead, check target_accepts_data() in io_opts_to_rebalance_opts(),
before creating the bch_extent_rebalance entry.
This fixes (one?) cause of rebalance_work accounting being off.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
|
|
Spotted by sparse.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
|
|
The discard path is supposed to issue journal flushes when there's too
many buckets empty buckets that need a journal commit before they can be
written to again, but at some point this code seems to have been lost.
Bring it back with a new optimization to make sure we don't issue too
many journal flushes: the journal now tracks the sequence number of the
most recent flush in progress, which the discard path uses when deciding
which buckets need a journal flush.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
|
|
In the previous commit b3d82c2f2761, code was added to prevent journal sequence
overflow. Among them, the code added to journal_entry_open() uses the
bch2_fs_fatal_err_on() function to handle errors.
However, __journal_res_get() , which calls journal_entry_open() , calls
journal_entry_open() while holding journal->lock , but bch2_fs_fatal_err_on()
internally tries to acquire journal->lock , which results in a deadlock.
So we need to add a locked helper to handle fatal errors even when the
journal->lock is held.
Fixes: b3d82c2f2761 ("bcachefs: Guard against journal seq overflow")
Signed-off-by: Jeongjun Park <aha310510@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
|
|
For some unknown reason, checks on struct bkey_s_c_snapshot and struct
bkey_s_c_snapshot_tree pointers are missing.
Therefore, I think it would be appropriate to fix the incorrect pointer checking
through this patch.
Fixes: 4bd06f07bcb5 ("bcachefs: Fixes for snapshot_tree.master_subvol")
Signed-off-by: Jeongjun Park <aha310510@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
|
|
Add an (initial?) patch submission checklist, focusing mainly on
testing.
Yes, all patches must be tested, and that starts (but does not end) with
the patch author.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
|
|
The destination argument of memtostr*() and strtomem*() must be a
fixed-size char array at compile time, so there is no need to use
__builtin_object_size() (which is useful for when an argument is
either a pointer or unknown). Instead use ARRAY_SIZE(), which has the
benefit of working around a bug in Clang (fixed[1] in 15+) that got
__builtin_object_size() wrong sometimes.
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202501310832.kiAeOt2z-lkp@intel.com/
Suggested-by: Kent Overstreet <kent.overstreet@linux.dev>
Link: https://github.com/llvm/llvm-project/commit/d8e0a6d5e9dd2311641f9a8a5d2bf90829951ddc [1]
Tested-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Kees Cook <kees@kernel.org>
|
|
In preparation for adding stricter type checking to the str/mem*()
helpers, provide a way to check that a variable is a byte array
via __must_be_byte_array().
Suggested-by: Kent Overstreet <kent.overstreet@linux.dev>
Signed-off-by: Kees Cook <kees@kernel.org>
|
|
The C kernel helpers for evaluating C Strings were positioned where they
were visible to assembly inclusion, which was not intended. Move them
into the kernel and C-only area of the header so future changes won't
confuse the assembler.
Fixes: d7a516c6eeae ("compiler.h: Fix undefined BUILD_BUG_ON_ZERO()")
Fixes: 559048d156ff ("string: Check for "nonstring" attribute on strscpy() arguments")
Reviewed-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Kees Cook <kees@kernel.org>
|
|
When using Rust on the x86 architecture, we are currently using the
unstable target.json feature to specify the compilation target. Rustc is
going to change how softfloat is specified in the target.json file on
x86, thus update generate_rust_target.rs to specify softfloat using the
new option.
Note that if you enable this parameter with a compiler that does not
recognize it, then that triggers a warning but it does not break the
build.
[ For future reference, this solves the following error:
RUSTC L rust/core.o
error: Error loading target specification: target feature
`soft-float` is incompatible with the ABI but gets enabled in
target spec. Run `rustc --print target-list` for a list of
built-in targets
- Miguel ]
Cc: <stable@vger.kernel.org> # Needed in 6.12.y and 6.13.y only (Rust is pinned in older LTSs).
Link: https://github.com/rust-lang/rust/pull/136146
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com> # for x86
Link: https://lore.kernel.org/r/20250203-rustc-1-86-x86-softfloat-v1-1-220a72a5003e@google.com
[ Added 6.13.y too to Cc: stable tag and added reasoning to avoid
over-backporting. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
|
|
The uretprobe syscall is implemented as a performance enhancement on
x86_64 by having the kernel inject a call to it on function exit; User
programs cannot call this system call explicitly.
As such, this syscall is considered a kernel implementation detail and
should not be filtered by seccomp.
Enhance the seccomp bpf test suite to check that uretprobes can be
attached to processes without the killing the process regardless of
seccomp policy.
Signed-off-by: Eyal Birger <eyal.birger@gmail.com>
Link: https://lore.kernel.org/r/20250202162921.335813-3-eyal.birger@gmail.com
[kees: Skip archs without __NR_uretprobe]
Signed-off-by: Kees Cook <kees@kernel.org>
|
|
When attaching uretprobes to processes running inside docker, the attached
process is segfaulted when encountering the retprobe.
The reason is that now that uretprobe is a system call the default seccomp
filters in docker block it as they only allow a specific set of known
syscalls. This is true for other userspace applications which use seccomp
to control their syscall surface.
Since uretprobe is a "kernel implementation detail" system call which is
not used by userspace application code directly, it is impractical and
there's very little point in forcing all userspace applications to
explicitly allow it in order to avoid crashing tracked processes.
Pass this systemcall through seccomp without depending on configuration.
Note: uretprobe is currently only x86_64 and isn't expected to ever be
supported in i386.
Fixes: ff474a78cef5 ("uprobe: Add uretprobe syscall to speed up return probe")
Reported-by: Rafael Buchbinder <rafi@rbk.io>
Closes: https://lore.kernel.org/lkml/CAHsH6Gs3Eh8DFU0wq58c_LF8A4_+o6z456J7BidmcVY2AqOnHQ@mail.gmail.com/
Link: https://lore.kernel.org/lkml/20250121182939.33d05470@gandalf.local.home/T/#me2676c378eff2d6a33f3054fed4a5f3afa64e65b
Link: https://lore.kernel.org/lkml/20250128145806.1849977-1-eyal.birger@gmail.com/
Cc: stable@vger.kernel.org
Signed-off-by: Eyal Birger <eyal.birger@gmail.com>
Link: https://lore.kernel.org/r/20250202162921.335813-2-eyal.birger@gmail.com
[kees: minimized changes for easier backporting, tweaked commit log]
Signed-off-by: Kees Cook <kees@kernel.org>
|
|
In union test_small_end, the small members are three and four.
Fixes: e71a29db79da1946 ("stackinit: Add union initialization to selftests")
Closes: https://lore.kernel.org/CAMuHMdWvcKOc6v5o3-9-SqP_4oh5-GZQjZZb=-krhY=mVRED_Q@mail.gmail.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/3f8faa2d7d0d6b36571093ab0fb1fd5157abd7bb.1738593178.git.geert+renesas@glider.be
Signed-off-by: Kees Cook <kees@kernel.org>
|
|
The stack frame on m68k is very sensitive to the size of what needs to
be stored. Like done for long string testing, reduce the size of the
large trailing struct in the union initialization testing.
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Closes: https://lore.kernel.org/all/CAMuHMdXW8VbtOAixO7w+aDOG70aZtZ50j1Ybcr8B3eYnRUcrcA@mail.gmail.com
Fixes: e71a29db79da ("stackinit: Add union initialization to selftests")
Link: https://lore.kernel.org/r/20250204174509.work.711-kees@kernel.org
Signed-off-by: Kees Cook <kees@kernel.org>
Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
|
|
amd_pstate_update_limits() takes a cpufreq_policy reference but doesn't
decrement the refcount in one of the exit paths, fix that.
Fixes: 45722e777fd9 ("cpufreq: amd-pstate: Optimize amd_pstate_update_limits()")
Signed-off-by: Dhananjay Ugwekar <dhananjay.ugwekar@amd.com>
Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>
Link: https://lore.kernel.org/r/20250205112523.201101-10-dhananjay.ugwekar@amd.com
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
|
|
ASAN generates special synthetic symbols to help check for ODR
violations. These synthetic symbols lack debug information, so
gendwarfksyms emits warnings when processing them. No code should ever
have a dependency on these symbols, so we should not be exporting them,
just like the __cfi symbols.
Signed-off-by: Matthew Maurer <mmaurer@google.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20250122-gendwarfksyms-kasan-rust-v1-1-5ee5658f4fb6@google.com
[ Fixed typo in commit message. Slightly reworded title. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
|
|
When we reenable TPH after changing a Steering Tag value, we need the
actual TPH Requester Enable value, not the ST Mode (which only happens to
work out by chance for non-extended TPH in interrupt vector mode).
Link: https://lore.kernel.org/r/13118098116d7bce07aa20b8c52e28c7d1847246.1738759933.git.robin.murphy@arm.com
Fixes: d2e8a34876ce ("PCI/TPH: Add Steering Tag support")
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Wei Huang <wei.huang2@amd.com>
|
|
This seems to break the build when building with gcc15:
Unable to generate bindings: ClangDiagnostic("error: unknown
argument: '-fzero-init-padding-bits=all'\n")
Thus skip that flag.
Signed-off-by: Justin M. Forbes <jforbes@fedoraproject.org>
Fixes: dce4aab8441d ("kbuild: Use -fzero-init-padding-bits=all")
Reviewed-by: Kees Cook <kees@kernel.org>
Link: https://lore.kernel.org/r/20250129215003.1736127-1-jforbes@fedoraproject.org
[ Slightly reworded commit. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
|
Sean Christopherson
Linus Torvalds
Rafael J. Wysocki
Steven Rostedt
Nathan Chancellor
WangYuli
Hector Martin
Pavel Machek
Mateusz Guzik
Christian Brauner
Amir Goldstein
Miklos Szeredi
Andreas Gruenbacher
Brahmajit Das
Su Hui
Frederic Weisbecker
Geert Uytterhoeven
Kent Overstreet
Jeongjun Park
Kees Cook
Alice Ryhl
Eyal Birger
Dhananjay Ugwekar
Matthew Maurer
Robin Murphy
Justin M. Forbes