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Linux kernel
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Add a maintainers entry now that the PREEMPT_RT bits are merged. Steven
volunteered and asked for the list.
There are no files associated with this entry since it is spread over the
kernel. It serves as entry for people knowing what they look for. There is
a keyword added so if PREEMPT_RT is mentioned somewhere, then the entry
will be picked up.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Pavel Machek <pavel@denx.de>
Link: https://lore.kernel.org/all/20241015151132.Erx81G9f@linutronix.de
Conflicts:
kernel/sched/ext.c
There's a context conflict between this upstream commit:
3fdb9ebcec10 sched_ext: Start schedulers with consistent p->scx.slice values
... and this fix in sched/urgent:
98442f0ccd82 sched: Fix delayed_dequeue vs switched_from_fair()
Resolve it.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Sean noted that ever since commit 152e11f6df29 ("sched/fair: Implement
delayed dequeue") KVM's preemption notifiers have started
mis-classifying preemption vs blocking.
Notably p->on_rq is no longer sufficient to determine if a task is
runnable or blocked -- the aforementioned commit introduces tasks that
remain on the runqueue even through they will not run again, and
should be considered blocked for many cases.
Add the task_is_runnable() helper to classify things and audit all
external users of the p->on_rq state. Also add a few comments.
Fixes: 152e11f6df29 ("sched/fair: Implement delayed dequeue")
Reported-by: Sean Christopherson <seanjc@google.com>
Tested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20241010091843.GK33184@noisy.programming.kicks-ass.net
Pull rdma fixes from Jason Gunthorpe:
"Several miscellaneous fixes. A lot of bnxt_re activity, there will be
more rc patches there coming.
- Many bnxt_re bug fixes - Memory leaks, kasn, NULL pointer deref,
soft lockups, error unwinding and some small functional issues
- Error unwind bug in rdma netlink
- Two issues with incorrect VLAN detection for iWarp
- skb_splice_from_iter() splat in siw
- Give SRP slab caches unique names to resolve the merge window
WARN_ON regression"
* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma:
RDMA/bnxt_re: Fix the GID table length
RDMA/bnxt_re: Fix a bug while setting up Level-2 PBL pages
RDMA/bnxt_re: Change the sequence of updating the CQ toggle value
RDMA/bnxt_re: Fix an error path in bnxt_re_add_device
RDMA/bnxt_re: Avoid CPU lockups due fifo occupancy check loop
RDMA/bnxt_re: Fix a possible NULL pointer dereference
RDMA/bnxt_re: Return more meaningful error
RDMA/bnxt_re: Fix incorrect dereference of srq in async event
RDMA/bnxt_re: Fix out of bound check
RDMA/bnxt_re: Fix the max CQ WQEs for older adapters
RDMA/srpt: Make slab cache names unique
RDMA/irdma: Fix misspelling of "accept*"
RDMA/cxgb4: Fix RDMA_CM_EVENT_UNREACHABLE error for iWARP
RDMA/siw: Add sendpage_ok() check to disable MSG_SPLICE_PAGES
RDMA/core: Fix ENODEV error for iWARP test over vlan
RDMA/nldev: Fix NULL pointer dereferences issue in rdma_nl_notify_event
RDMA/bnxt_re: Fix the max WQEs used in Static WQE mode
RDMA/bnxt_re: Add a check for memory allocation
RDMA/bnxt_re: Fix incorrect AVID type in WQE structure
RDMA/bnxt_re: Fix a possible memory leak
Since sched_delayed tasks remain queued even after blocking, the load
balancer can migrate them between runqueues while PSI considers them
to be asleep. As a result, it misreads the migration requeue followed
by a wakeup as a double queue:
psi: inconsistent task state! task=... cpu=... psi_flags=4 clear=. set=4
First, call psi_enqueue() after p->sched_class->enqueue_task(). A
wakeup will clear p->se.sched_delayed while a migration will not, so
psi can use that flag to tell them apart.
Then teach psi to migrate any "sleep" state when delayed-dequeue tasks
are being migrated.
Delayed-dequeue tasks can be revived by ttwu_runnable(), which will
call down with a new ENQUEUE_DELAYED. Instead of further complicating
the wakeup conditional in enqueue_task(), identify migration contexts
instead and default to wakeup handling for all other cases.
It's not just the warning in dmesg, the task state corruption causes a
permanent CPU pressure indication, which messes with workload/machine
health monitoring.
Debugged-by-and-original-fix-by: K Prateek Nayak <kprateek.nayak@amd.com>
Fixes: 152e11f6df29 ("sched/fair: Implement delayed dequeue")
Closes: https://lore.kernel.org/lkml/20240830123458.3557-1-spasswolf@web.de/
Closes: https://lore.kernel.org/all/cd67fbcd-d659-4822-bb90-7e8fbb40a856@molgen.mpg.de/
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: K Prateek Nayak <kprateek.nayak@amd.com>
Link: https://lkml.kernel.org/r/20241010193712.GC181795@cmpxchg.org
Pull btrfs fixes from David Sterba:
- regression fix: dirty extents tracked in xarray for qgroups must be
adjusted for 32bit platforms
- fix potentially freeing uninitialized name in fscrypt structure
- fix warning about unneeded variable in a send callback
* tag 'for-6.12-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: fix uninitialized pointer free on read_alloc_one_name() error
btrfs: send: cleanup unneeded return variable in changed_verity()
btrfs: fix uninitialized pointer free in add_inode_ref()
btrfs: use sector numbers as keys for the dirty extents xarray
GID table length is reported by FW. The gid index which is passed to the
driver during modify_qp/create_ah is restricted by the sgid_index field of
struct ib_global_route. sgid_index is u8 and the max sgid possible is
256.
Each GID entry in HW will have 2 GID entries in the kernel gid table. So
we can support twice the gid table size reported by FW. Also, restrict the
max GID to 256 also.
Fixes: 847b97887ed4 ("RDMA/bnxt_re: Restrict the max_gids to 256")
Link: https://patch.msgid.link/r/1728373302-19530-11-git-send-email-selvin.xavier@broadcom.com
Signed-off-by: Kalesh AP <kalesh-anakkur.purayil@broadcom.com>
Signed-off-by: Selvin Xavier <selvin.xavier@broadcom.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
psi_dequeue() in for blocked task expects psi_sched_switch() to clear
the TSK_.*RUNNING PSI flags and set the TSK_IOWAIT flags however
psi_sched_switch() uses "!task_on_rq_queued(prev)" to detect if the task
is blocked or still runnable which is no longer true with DELAY_DEQUEUE
since a blocking task can be left queued on the runqueue.
This can lead to PSI splats similar to:
psi: inconsistent task state! task=... cpu=... psi_flags=4 clear=0 set=4
when the task is requeued since the TSK_RUNNING flag was not cleared
when the task was blocked.
Explicitly communicate that the task was blocked to psi_sched_switch()
even if it was delayed and is still on the runqueue.
[ prateek: Broke off the relevant part from [1], commit message ]
Fixes: 152e11f6df29 ("sched/fair: Implement delayed dequeue")
Closes: https://lore.kernel.org/lkml/20240830123458.3557-1-spasswolf@web.de/
Closes: https://lore.kernel.org/all/cd67fbcd-d659-4822-bb90-7e8fbb40a856@molgen.mpg.de/
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Not-yet-signed-off-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: K Prateek Nayak <kprateek.nayak@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Johannes Weiner <hannes@cmpxchg.org>
Link: https://lore.kernel.org/lkml/20241004123506.GR18071@noisy.programming.kicks-ass.net/ [1]
Pull smb server fixes from Steve French:
- fix race between session setup and session logoff
- add supplementary group support
* tag 'v6.12-rc3-ksmbd-fixes' of git://git.samba.org/ksmbd:
ksmbd: add support for supplementary groups
ksmbd: fix user-after-free from session log off
The function read_alloc_one_name() does not initialize the name field of
the passed fscrypt_str struct if kmalloc fails to allocate the
corresponding buffer. Thus, it is not guaranteed that
fscrypt_str.name is initialized when freeing it.
This is a follow-up to the linked patch that fixes the remaining
instances of the bug introduced by commit e43eec81c516 ("btrfs: use
struct qstr instead of name and namelen pairs").
Link: https://lore.kernel.org/linux-btrfs/20241009080833.1355894-1-jroi.martin@gmail.com/
Fixes: e43eec81c516 ("btrfs: use struct qstr instead of name and namelen pairs")
CC: stable@vger.kernel.org # 6.1+
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Roi Martin <jroi.martin@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Avoid memory corruption while setting up Level-2 PBL pages for the non MR
resources when num_pages > 256K.
There will be a single PDE page address (contiguous pages in the case of >
PAGE_SIZE), but, current logic assumes multiple pages, leading to invalid
memory access after 256K PBL entries in the PDE.
Fixes: 0c4dcd602817 ("RDMA/bnxt_re: Refactor hardware queue memory allocation")
Link: https://patch.msgid.link/r/1728373302-19530-10-git-send-email-selvin.xavier@broadcom.com
Signed-off-by: Bhargava Chenna Marreddy <bhargava.marreddy@broadcom.com>
Signed-off-by: Selvin Xavier <selvin.xavier@broadcom.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Commit 2e0199df252a ("sched/fair: Prepare exit/cleanup paths for delayed_dequeue")
and its follow up fixes try to deal with a rather unfortunate
situation where is task is enqueued in a new class, even though it
shouldn't have been. Mostly because the existing ->switched_to/from()
hooks are in the wrong place for this case.
This all led to Paul being able to trigger failures at something like
once per 10k CPU hours of RCU torture.
For now, do the ugly thing and move the code to the right place by
ignoring the switch hooks.
Note: Clean up the whole sched_class::switch*_{to,from}() thing.
Fixes: 2e0199df252a ("sched/fair: Prepare exit/cleanup paths for delayed_dequeue")
Reported-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20241003185037.GA5594@noisy.programming.kicks-ass.net
Pull crypto fixes from Herbert Xu:
- Remove bogus testmgr ENOENT error messages
- Ensure algorithm is still alive before marking it as tested
- Disable buggy hash algorithms in marvell/cesa
* tag 'v6.12-p3' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
crypto: marvell/cesa - Disable hash algorithms
crypto: testmgr - Hide ENOENT errors better
crypto: api - Fix liveliness check in crypto_alg_tested
Even though system user has a supplementary group, It gets
NT_STATUS_ACCESS_DENIED when attempting to create file or directory.
This patch add KSMBD_EVENT_LOGIN_REQUEST_EXT/RESPONSE_EXT netlink events
to get supplementary groups list. The new netlink event doesn't break
backward compatibility when using old ksmbd-tools.
Co-developed-by: Atte Heikkilä <atteh.mailbox@gmail.com>
Signed-off-by: Atte Heikkilä <atteh.mailbox@gmail.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
As all changed_* functions need to return something, just return 0
directly here, as the verity status is passed via the context.
Reported by LKP: fs/btrfs/send.c:6877:5-8: Unneeded variable: "ret". Return "0" on line 6883
Reported-by: kernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/oe-kbuild-all/202410092305.WbyqspH8-lkp@intel.com/
Signed-off-by: Christian Heusel <christian@heusel.eu>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
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