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Add flags to describe checks for integrity meta buffer. Also, introduce
a new 'uio_meta' structure that upper layer can use to pass the
meta/integrity information.
Signed-off-by: Kanchan Joshi <joshi.k@samsung.com>
Signed-off-by: Anuj Gupta <anuj20.g@samsung.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20241128112240.8867-5-anuj20.g@samsung.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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This patch refactors bio_integrity_map_user to accept iov_iter as
argument. This is a prep patch.
Signed-off-by: Anuj Gupta <anuj20.g@samsung.com>
Signed-off-by: Kanchan Joshi <joshi.k@samsung.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Link: https://lore.kernel.org/r/20241128112240.8867-4-anuj20.g@samsung.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Introduce BIP_CLONE_FLAGS describing integrity flags that should be
inherited in the cloned bip from the parent.
Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Anuj Gupta <anuj20.g@samsung.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Link: https://lore.kernel.org/r/20241128112240.8867-2-anuj20.g@samsung.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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A preparation / cleanup patch simplifying the buf ring - mmap
synchronisation. Instead of relying on RCU, which is trickier, do it by
grabbing the mmap_lock when when anyone tries to publish or remove a
registered buffer to / from ->io_bl_xa.
Modifications of the xarray should always be protected by both
->uring_lock and ->mmap_lock, while lookups should hold either of them.
While a struct io_buffer_list is in the xarray, the mmap related fields
like ->flags and ->buf_pages should stay stable.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/af13bde56ee1a26bcaefaa9aad37a9ea318a590e.1732886067.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Convert internal parts of the CQ/SQ array managment to the region API.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/46fc3c801290d6b1ac16023d78f6b8e685c87fd6.1732886067.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Convert internal parts of the SQ managment to the region API.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/1fb73ced6b835cb319ab0fe1dc0b2e982a9a5650.1732886067.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Add internal flags for struct io_mapped_region. The first flag we need
is IO_REGION_F_VMAPPED, that indicates that the pointer has to be
unmapped on region destruction. For now all regions are vmap'ed, so it's
set unconditionally.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/5a3d8046a038da97c0f8a8c8f1733fa3fc689d31.1732886067.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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->resize_lock is used for resizing rings, but it's a good idea to reuse
it in other cases as well. Rename it into mmap_lock as it's protects
from races with mmap.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/68f705306f3ac4d2fb999eb80ea1615015ce9f7f.1732886067.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Since the dynamic preemption has been enabled for PREEMPT_RT we have now
CONFIG_PREEMPT and CONFIG_PREEMPT_RT set simultaneously. This affects
the vermagic strings which comes now PREEMPT with PREEMPT_RT enabled.
The PREEMPT_RT module usually can not be loaded on a PREEMPT kernel
because some symbols are missing.
However if the symbols are fine then it continues and it crashes later.
The problem is that the struct module has a different layout and the
num_exentries or init members are at a different position leading to a
crash later on. This is not necessary caught by the size check in
elf_validity_cache_index_mod() because the mem member has an alignment
requirement of __module_memory_align which is big enough keep the total
size unchanged. Therefore we should keep the string accurate instead of
removing it.
Move the PREEMPT_RT check before the PREEMPT so that it takes precedence
if both symbols are enabled.
Fixes: 35772d627b55c ("sched: Enable PREEMPT_DYNAMIC for PREEMPT_RT")
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Petr Pavlu <petr.pavlu@suse.com>
Link: https://lore.kernel.org/r/20241205160602.3lIAsJRT@linutronix.de
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
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The routine is used in link_path_walk() for every path component.
To my reading the entire point of the fence was to grab a fully
populated mnt_idmap, but that's already going to happen with mere
consume fence.
Eliminates an actual fence on arm64.
Signed-off-by: Mateusz Guzik <mjguzik@gmail.com>
Link: https://lore.kernel.org/r/20241130051712.1036527-1-mjguzik@gmail.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
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When utilized it dodges strlen() in vfs_readlink(), giving about 1.5%
speed up when issuing readlink on /initrd.img on ext4.
Filesystems opt in by calling inode_set_cached_link() when creating an
inode.
The size is stored in a new union utilizing the same space as i_devices,
thus avoiding growing the struct or taking up any more space.
Churn-wise the current readlink_copy() helper is patched to accept the
size instead of calculating it.
Signed-off-by: Mateusz Guzik <mjguzik@gmail.com>
Link: https://lore.kernel.org/r/20241120112037.822078-2-mjguzik@gmail.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
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Add some kernel-doc notation to structs in fiemap header files
then pull that into Documentation/filesystems/fiemap.rst
instead of duplicating the header file structs in fiemap.rst.
This helps to future-proof fiemap.rst against struct changes.
Add missing flags documentation from header files into fiemap.rst
for FIEMAP_FLAG_CACHE and FIEMAP_EXTENT_SHARED.
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://lore.kernel.org/r/20241121011352.201907-1-rdunlap@infradead.org
Cc: Christoph Hellwig <hch@lst.de>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Jan Kara <jack@suse.cz>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-doc@vger.kernel.org
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
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Annotation already used to be there, but got lost in 52ac39e5db5148f7
("seqlock: seqcount_t: Implement all read APIs as statement expressions").
Does not look like it was intentional.
Without it gcc 12 decides to compile the following in path_init:
nd->m_seq = __read_seqcount_begin(&mount_lock.seqcount);
nd->r_seq = __read_seqcount_begin(&rename_lock.seqcount);
into 2 cases of conditional jumps forward if the value is even, aka
branch prediction miss by default in the common case on x86-64.
With the patch jumps are only for odd values.
before:
[snip]
mov 0x104fe96(%rip),%eax # 0xffffffff82409680 <mount_lock>
test $0x1,%al
je 0xffffffff813b97fa <path_init+122>
pause
mov 0x104fe8a(%rip),%eax # 0xffffffff82409680 <mount_lock>
test $0x1,%al
jne 0xffffffff813b97ee <path_init+110>
mov %eax,0x48(%rbx)
mov 0x104fdfd(%rip),%eax # 0xffffffff82409600 <rename_lock>
test $0x1,%al
je 0xffffffff813b9813 <path_init+147>
pause
mov 0x104fdf1(%rip),%eax # 0xffffffff82409600 <rename_lock>
test $0x1,%al
jne 0xffffffff813b9807 <path_init+135>
[/snip]
after:
[snip]
mov 0x104fec6(%rip),%eax # 0xffffffff82409680 <mount_lock>
test $0x1,%al
jne 0xffffffff813b99af <path_init+607>
mov %eax,0x48(%rbx)
mov 0x104fe35(%rip),%eax # 0xffffffff82409600 <rename_lock>
test $0x1,%al
jne 0xffffffff813b999d <path_init+589>
[/snip]
Interestingly .text gets slightly smaller (as reported by size(1)):
before: 20702563
after: 20702429
Signed-off-by: Mateusz Guzik <mjguzik@gmail.com>
Link: https://lore.kernel.org/r/20230727180355.813995-1-mjguzik@gmail.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
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Allow bind-mounting pidfds. Similar to nsfs let's allow bind-mounts for
pidfds. This allows pidfds to be safely recovered and checked for
process recycling.
Link: https://lore.kernel.org/r/20241219-work-pidfs-mount-v1-1-dbc56198b839@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull misc fixes from Andrew Morton:
"25 hotfixes. 16 are cc:stable. 19 are MM and 6 are non-MM.
The usual bunch of singletons and doubletons - please see the relevant
changelogs for details"
* tag 'mm-hotfixes-stable-2024-12-21-12-09' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (25 commits)
mm: huge_memory: handle strsep not finding delimiter
alloc_tag: fix set_codetag_empty() when !CONFIG_MEM_ALLOC_PROFILING_DEBUG
alloc_tag: fix module allocation tags populated area calculation
mm/codetag: clear tags before swap
mm/vmstat: fix a W=1 clang compiler warning
mm: convert partially_mapped set/clear operations to be atomic
nilfs2: fix buffer head leaks in calls to truncate_inode_pages()
vmalloc: fix accounting with i915
mm/page_alloc: don't call pfn_to_page() on possibly non-existent PFN in split_large_buddy()
fork: avoid inappropriate uprobe access to invalid mm
nilfs2: prevent use of deleted inode
zram: fix uninitialized ZRAM not releasing backing device
zram: refuse to use zero sized block device as backing device
mm: use clear_user_(high)page() for arch with special user folio handling
mm: introduce cpu_icache_is_aliasing() across all architectures
mm: add RCU annotation to pte_offset_map(_lock)
mm: correctly reference merged VMA
mm: use aligned address in copy_user_gigantic_page()
mm: use aligned address in clear_gigantic_page()
mm: shmem: fix ShmemHugePages at swapout
...
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Pull BPF fixes from Daniel Borkmann:
- Fix inlining of bpf_get_smp_processor_id helper for !CONFIG_SMP
systems (Andrea Righi)
- Fix BPF USDT selftests helper code to use asm constraint "m" for
LoongArch (Tiezhu Yang)
- Fix BPF selftest compilation error in get_uprobe_offset when
PROCMAP_QUERY is not defined (Jerome Marchand)
- Fix BPF bpf_skb_change_tail helper when used in context of BPF
sockmap to handle negative skb header offsets (Cong Wang)
- Several fixes to BPF sockmap code, among others, in the area of
socket buffer accounting (Levi Zim, Zijian Zhang, Cong Wang)
* tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
selftests/bpf: Test bpf_skb_change_tail() in TC ingress
selftests/bpf: Introduce socket_helpers.h for TC tests
selftests/bpf: Add a BPF selftest for bpf_skb_change_tail()
bpf: Check negative offsets in __bpf_skb_min_len()
tcp_bpf: Fix copied value in tcp_bpf_sendmsg
skmsg: Return copied bytes in sk_msg_memcopy_from_iter
tcp_bpf: Add sk_rmem_alloc related logic for tcp_bpf ingress redirection
tcp_bpf: Charge receive socket buffer in bpf_tcp_ingress()
selftests/bpf: Fix compilation error in get_uprobe_offset()
selftests/bpf: Use asm constraint "m" for LoongArch
bpf: Fix bpf_get_smp_processor_id() on !CONFIG_SMP
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size_t is the correct type for a count of objects that can fit in
memory: this also means heaps now have the same memory layout as darrays
(fs/bcachefs/darray.h), and darrays can be used as heaps.
Cc: Kuan-Wei Chiu <visitorckw@gmail.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Coly Li <colyli@suse.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
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Here is the patch which uses existing constant table:
Currently, when using bcachefs-tools to set options, bool-type options
can only accept 1 or 0. Add support for accepting true/false and yes/no
for these options.
Signed-off-by: Integral <integral@murena.io>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Acked-by: David Howells <dhowells@redhat.com>
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Change the way netfslib collects read results to do all the collection for
a particular read request using a single work item that walks along the
subrequest queue as subrequests make progress or complete, unlocking folios
progressively rather than doing the unlock in parallel as parallel requests
come in.
The code is remodelled to be more like the write-side code, though only
using a single stream. This makes it more directly comparable and thus
easier to duplicate fixes between the two sides.
This has a number of advantages:
(1) It's simpler. There doesn't need to be a complex donation mechanism
to handle mismatches between the size and alignment of subrequests and
folios. The collector unlocks folios as the subrequests covering each
complete.
(2) It should cause less scheduler overhead as there's a single work item
in play unlocking pages in parallel when a read gets split up into a
lot of subrequests instead of one per subrequest.
Whilst the parallellism is nice in theory, in practice, the vast
majority of loads are sequential reads of the whole file, so
committing a bunch of threads to unlocking folios out of order doesn't
help in those cases.
(3) It should make it easier to implement content decryption. A folio
cannot be decrypted until all the requests that contribute to it have
completed - and, again, most loads are sequential and so, most of the
time, we want to begin decryption sequentially (though it's great if
the decryption can happen in parallel).
There is a disadvantage in that we're losing the ability to decrypt and
unlock things on an as-things-arrive basis which may affect some
applications.
Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/r/20241216204124.3752367-28-dhowells@redhat.com
cc: Jeff Layton <jlayton@kernel.org>
cc: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
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Add support for caching the content of a file that contains a single
monolithic object that must be read/written with a single I/O operation,
such as an AFS directory.
Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/r/20241216204124.3752367-20-dhowells@redhat.com
cc: Jeff Layton <jlayton@kernel.org>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: netfs@lists.linux.dev
cc: linux-afs@lists.infradead.org
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
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Add two netfslib functions to build up or clean up a buffer in a
folio_queue. The first, netfs_alloc_folioq_buffer() will add folios to a
buffer, extending up at least to the given size. If it can, it will add
multipage folios. The folios are optionally have the mapping set and will
have the index set according to the distance from the front of the folio
queue.
The second function will free up a folio queue and put any folios in the
queue that have the first mark set.
The netfs_folio tracepoint is also altered to cope with folios that have a
NULL mapping, and the folios being added/put will have trace lines emitted
and will be accounted in the stats.
Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/r/20241216204124.3752367-19-dhowells@redhat.com
cc: Jeff Layton <jlayton@kernel.org>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: netfs@lists.linux.dev
cc: linux-afs@lists.infradead.org
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
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Drop the was_async argument from netfs_read_subreq_terminated(). Almost
every caller is either in process context and passes false. Some
filesystems delegate the call to a workqueue to avoid doing the work in
their network message queue parsing thread.
The only exception is netfs_cache_read_terminated() which handles
completion in the cache - which is usually a callback from the backing
filesystem in softirq context, though it can be from process context if an
error occurred. In this case, delegate to a workqueue.
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/r/CAHk-=wiVC5Cgyz6QKXFu6fTaA6h4CjexDR-OV9kL6Vo5x9v8=A@mail.gmail.com/
Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/r/20241216204124.3752367-10-dhowells@redhat.com
cc: Jeff Layton <jlayton@kernel.org>
cc: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
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Drop the error argument from netfs_read_subreq_terminated() in favour of
passing the value in subreq->error.
Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/r/20241216204124.3752367-9-dhowells@redhat.com
cc: Jeff Layton <jlayton@kernel.org>
cc: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
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A rolling buffer is a series of folios held in a list of folio_queues. New
folios and folio_queue structs may be inserted at the head simultaneously
with spent ones being removed from the tail without the need for locking.
The rolling buffer includes an iov_iter and it has to be careful managing
this as the list of folio_queues is extended such that an oops doesn't
incurred because the iterator was pointing to the end of a folio_queue
segment that got appended to and then removed.
We need to use the mechanism twice, once for read and once for write, and,
in future patches, we will use a second rolling buffer to handle bounce
buffering for content encryption.
Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/r/20241216204124.3752367-6-dhowells@redhat.com
cc: Jeff Layton <jlayton@kernel.org>
cc: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
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Add a tracepoint to log the lifespan of folio_queue structs. For tracing
illustrative purposes, folio_queues are tagged with the debug ID of
whatever they're related to (typically a netfs_io_request) and a debug ID
of their own.
Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/r/20241216204124.3752367-5-dhowells@redhat.com
cc: Jeff Layton <jlayton@kernel.org>
cc: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
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Provide and use folio_queue allocation and free functions to combine the
allocation, initialisation and stat (un)accounting steps that are repeated
in several places.
Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/r/20241216204124.3752367-4-dhowells@redhat.com
cc: Jeff Layton <jlayton@kernel.org>
cc: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
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Pull io_uring fixes from Jens Axboe:
- Fix for a file ref leak for registered ring fds
- Turn the ->timeout_lock into a raw spinlock, as it nests under the
io-wq lock which is a raw spinlock as it's called from the scheduler
side
- Limit ring resizing to DEFER_TASKRUN for now. We will broaden this in
the future, but for now, ensure that it's only feasible on rings with
a single user
- Add sanity check for io-wq enqueuing
* tag 'io_uring-6.13-20241220' of git://git.kernel.dk/linux:
io_uring: check if iowq is killed before queuing
io_uring/register: limit ring resizing to DEFER_TASKRUN
io_uring: Fix registered ring file refcount leak
io_uring: make ctx->timeout_lock a raw spinlock
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netfs: Fix is-caching check in read-retry
The read-retry code checks the NETFS_RREQ_COPY_TO_CACHE flag to determine
if there might be failed reads from the cache that need turning into reads
from the server, with the intention of skipping the complicated part if it
can. The code that set the flag, however, got lost during the read-side
rewrite.
Fix the check to see if the cache_resources are valid instead. The flag
can then be removed.
Fixes: ee4cdf7ba857 ("netfs: Speed up buffered reading")
Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/r/3752048.1734381285@warthog.procyon.org.uk
cc: Jeff Layton <jlayton@kernel.org>
cc: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
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syzkaller reported recursion with a loop of three calls (netfs_rreq_assess,
netfs_retry_reads and netfs_rreq_terminated) hitting the limit of the stack
during an unbuffered or direct I/O read.
There are a number of issues:
(1) There is no limit on the number of retries.
(2) A subrequest is supposed to be abandoned if it does not transfer
anything (NETFS_SREQ_NO_PROGRESS), but that isn't checked under all
circumstances.
(3) The actual root cause, which is this:
if (atomic_dec_and_test(&rreq->nr_outstanding))
netfs_rreq_terminated(rreq, ...);
When we do a retry, we bump the rreq->nr_outstanding counter to
prevent the final cleanup phase running before we've finished
dispatching the retries. The problem is if we hit 0, we have to do
the cleanup phase - but we're in the cleanup phase and end up
repeating the retry cycle, hence the recursion.
Work around the problem by limiting the number of retries. This is based
on Lizhi Xu's patch[1], and makes the following changes:
(1) Replace NETFS_SREQ_NO_PROGRESS with NETFS_SREQ_MADE_PROGRESS and make
the filesystem set it if it managed to read or write at least one byte
of data. Clear this bit before issuing a subrequest.
(2) Add a ->retry_count member to the subrequest and increment it any time
we do a retry.
(3) Remove the NETFS_SREQ_RETRYING flag as it is superfluous with
->retry_count. If the latter is non-zero, we're doing a retry.
(4) Abandon a subrequest if retry_count is non-zero and we made no
progress.
(5) Use ->retry_count in both the write-side and the read-size.
[?] Question: Should I set a hard limit on retry_count in both read and
write? Say it hits 50, we always abandon it. The problem is that
these changes only mitigate the issue. As long as it made at least one
byte of progress, the recursion is still an issue. This patch
mitigates the problem, but does not fix the underlying cause. I have
patches that will do that, but it's an intrusive fix that's currently
pending for the next merge window.
The oops generated by KASAN looks something like:
BUG: TASK stack guard page was hit at ffffc9000482ff48 (stack is ffffc90004830000..ffffc90004838000)
Oops: stack guard page: 0000 [#1] PREEMPT SMP KASAN NOPTI
...
RIP: 0010:mark_lock+0x25/0xc60 kernel/locking/lockdep.c:4686
...
mark_usage kernel/locking/lockdep.c:4646 [inline]
__lock_acquire+0x906/0x3ce0 kernel/locking/lockdep.c:5156
lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5825
local_lock_acquire include/linux/local_lock_internal.h:29 [inline]
___slab_alloc+0x123/0x1880 mm/slub.c:3695
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
kmem_cache_alloc_noprof+0x2a7/0x2f0 mm/slub.c:4141
radix_tree_node_alloc.constprop.0+0x1e8/0x350 lib/radix-tree.c:253
idr_get_free+0x528/0xa40 lib/radix-tree.c:1506
idr_alloc_u32+0x191/0x2f0 lib/idr.c:46
idr_alloc+0xc1/0x130 lib/idr.c:87
p9_tag_alloc+0x394/0x870 net/9p/client.c:321
p9_client_prepare_req+0x19f/0x4d0 net/9p/client.c:644
p9_client_zc_rpc.constprop.0+0x105/0x880 net/9p/client.c:793
p9_client_read_once+0x443/0x820 net/9p/client.c:1570
p9_client_read+0x13f/0x1b0 net/9p/client.c:1534
v9fs_issue_read+0x115/0x310 fs/9p/vfs_addr.c:74
netfs_retry_read_subrequests fs/netfs/read_retry.c:60 [inline]
netfs_retry_reads+0x153a/0x1d00 fs/netfs/read_retry.c:232
netfs_rreq_assess+0x5d3/0x870 fs/netfs/read_collect.c:371
netfs_rreq_terminated+0xe5/0x110 fs/netfs/read_collect.c:407
netfs_retry_reads+0x155e/0x1d00 fs/netfs/read_retry.c:235
netfs_rreq_assess+0x5d3/0x870 fs/netfs/read_collect.c:371
netfs_rreq_terminated+0xe5/0x110 fs/netfs/read_collect.c:407
netfs_retry_reads+0x155e/0x1d00 fs/netfs/read_retry.c:235
netfs_rreq_assess+0x5d3/0x870 fs/netfs/read_collect.c:371
...
netfs_rreq_terminated+0xe5/0x110 fs/netfs/read_collect.c:407
netfs_retry_reads+0x155e/0x1d00 fs/netfs/read_retry.c:235
netfs_rreq_assess+0x5d3/0x870 fs/netfs/read_collect.c:371
netfs_rreq_terminated+0xe5/0x110 fs/netfs/read_collect.c:407
netfs_retry_reads+0x155e/0x1d00 fs/netfs/read_retry.c:235
netfs_rreq_assess+0x5d3/0x870 fs/netfs/read_collect.c:371
netfs_rreq_terminated+0xe5/0x110 fs/netfs/read_collect.c:407
netfs_dispatch_unbuffered_reads fs/netfs/direct_read.c:103 [inline]
netfs_unbuffered_read fs/netfs/direct_read.c:127 [inline]
netfs_unbuffered_read_iter_locked+0x12f6/0x19b0 fs/netfs/direct_read.c:221
netfs_unbuffered_read_iter+0xc5/0x100 fs/netfs/direct_read.c:256
v9fs_file_read_iter+0xbf/0x100 fs/9p/vfs_file.c:361
do_iter_readv_writev+0x614/0x7f0 fs/read_write.c:832
vfs_readv+0x4cf/0x890 fs/read_write.c:1025
do_preadv fs/read_write.c:1142 [inline]
__do_sys_preadv fs/read_write.c:1192 [inline]
__se_sys_preadv fs/read_write.c:1187 [inline]
__x64_sys_preadv+0x22d/0x310 fs/read_write.c:1187
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
Fixes: ee4cdf7ba857 ("netfs: Speed up buffered reading")
Closes: https://syzkaller.appspot.com/bug?extid=1fc6f64c40a9d143cfb6
Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/r/20241108034020.3695718-1-lizhi.xu@windriver.com/ [1]
Link: https://lore.kernel.org/r/20241213135013.2964079-9-dhowells@redhat.com
Tested-by: syzbot+885c03ad650731743489@syzkaller.appspotmail.com
Suggested-by: Lizhi Xu <lizhi.xu@windriver.com>
cc: Dominique Martinet <asmadeus@codewreck.org>
cc: Jeff Layton <jlayton@kernel.org>
cc: v9fs@lists.linux.dev
cc: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
Reported-by: syzbot+885c03ad650731743489@syzkaller.appspotmail.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
|
|
When we do sk_psock_verdict_apply->sk_psock_skb_ingress, an sk_msg will
be created out of the skb, and the rmem accounting of the sk_msg will be
handled by the skb.
For skmsgs in __SK_REDIRECT case of tcp_bpf_send_verdict, when redirecting
to the ingress of a socket, although we sk_rmem_schedule and add sk_msg to
the ingress_msg of sk_redir, we do not update sk_rmem_alloc. As a result,
except for the global memory limit, the rmem of sk_redir is nearly
unlimited. Thus, add sk_rmem_alloc related logic to limit the recv buffer.
Since the function sk_msg_recvmsg and __sk_psock_purge_ingress_msg are
used in these two paths. We use "msg->skb" to test whether the sk_msg is
skb backed up. If it's not, we shall do the memory accounting explicitly.
Fixes: 604326b41a6f ("bpf, sockmap: convert to generic sk_msg interface")
Signed-off-by: Zijian Zhang <zijianzhang@bytedance.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20241210012039.1669389-3-zijianzhang@bytedance.com
|
|
A common pattern seen when wake_qs are used to defer a wakeup
until after a lock is released is something like:
preempt_disable();
raw_spin_unlock(lock);
wake_up_q(wake_q);
preempt_enable();
So create some raw_spin_unlock*_wake() helper functions to clean
this up.
Applies on top of the fix I submitted here:
https://lore.kernel.org/lkml/20241212222138.2400498-1-jstultz@google.com/
NOTE: I recognise the unlock()/unlock_irq()/unlock_irqrestore()
variants creates its own duplication, which we could use a macro
to generate the similar functions, but I often dislike how those
generation macros making finding the actual implementation
harder, so I left the three functions as is. If folks would
prefer otherwise, let me know and I'll switch it.
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: John Stultz <jstultz@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20241217040803.243420-1-jstultz@google.com
|
|
/proc/schedstat file shows cpu and sched domain level scheduler
statistics. It does not show domain name instead shows domain level.
It will be very useful for tools like `perf sched stats`[1] to
aggragate domain level stats if domain names are shown in /proc/schedstat.
But sched domain name is guarded by CONFIG_SCHED_DEBUG. As per the
discussion[2], move sched domain name out of CONFIG_SCHED_DEBUG.
[1] https://lore.kernel.org/lkml/20241122084452.1064968-1-swapnil.sapkal@amd.com/
[2] https://lore.kernel.org/lkml/fcefeb4d-3acb-462d-9c9b-3df8d927e522@amd.com/
Suggested-by: "Gautham R. Shenoy" <gautham.shenoy@amd.com>
Signed-off-by: Swapnil Sapkal <swapnil.sapkal@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20241220063224.17767-5-swapnil.sapkal@amd.com
|
|
In /proc/schedstat, lb_imbalance reports the sum of imbalances
discovered in sched domains with each call to sched_balance_rq(), which is
not very useful because lb_imbalance does not mention whether the imbalance
is due to load, utilization, nr_tasks or misfit_tasks. Remove this field
from /proc/schedstat.
Currently there is no field in /proc/schedstat to report different types
of imbalances. Introduce new fields in /proc/schedstat to report the
total imbalances in load, utilization, nr_tasks or misfit_tasks.
Added fields to /proc/schedstat:
- lb_imbalance_load: Total imbalance due to load.
- lb_imbalance_util: Total imbalance due to utilization.
- lb_imbalance_task: Total imbalance due to number of tasks.
- lb_imbalance_misfit: Total imbalance due to misfit tasks.
Signed-off-by: Swapnil Sapkal <swapnil.sapkal@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Shrikanth Hegde <sshegde@linux.ibm.com>
Link: https://lore.kernel.org/r/20241220063224.17767-4-swapnil.sapkal@amd.com
|
|
In /proc/schedstat, lb_hot_gained reports the number hot tasks pulled
during load balance. This value is incremented in can_migrate_task()
if the task is migratable and hot. After incrementing the value,
load balancer can still decide not to migrate this task leading to wrong
accounting. Fix this by incrementing stats when hot tasks are detached.
This issue only exists in detach_tasks() where we can decide to not
migrate hot task even if it is migratable. However, in detach_one_task(),
we migrate it unconditionally.
[Swapnil: Handled the case where nr_failed_migrations_hot was not accounted properly and wrote commit log]
Fixes: d31980846f96 ("sched: Move up affinity check to mitigate useless redoing overhead")
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reported-by: "Gautham R. Shenoy" <gautham.shenoy@amd.com>
Not-yet-signed-off-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Swapnil Sapkal <swapnil.sapkal@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20241220063224.17767-2-swapnil.sapkal@amd.com
|
|
It was recently noticed that set_codetag_empty() might be used not only to
mark NULL alloctag references as empty to avoid warnings but also to reset
valid tags (in clear_page_tag_ref()). Since set_codetag_empty() is
defined as NOOP for CONFIG_MEM_ALLOC_PROFILING_DEBUG=n, such use of
set_codetag_empty() leads to subtle bugs. Fix set_codetag_empty() for
CONFIG_MEM_ALLOC_PROFILING_DEBUG=n to reset the tag reference.
Link: https://lkml.kernel.org/r/20241130001423.1114965-2-surenb@google.com
Fixes: a8fc28dad6d5 ("alloc_tag: introduce clear_page_tag_ref() helper function")
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Reported-by: David Wang <00107082@163.com>
Closes: https://lore.kernel.org/lkml/20241124074318.399027-1-00107082@163.com/
Cc: David Wang <00107082@163.com>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Cc: Mike Rapoport (Microsoft) <rppt@kernel.org>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Sourav Panda <souravpanda@google.com>
Cc: Yu Zhao <yuzhao@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
When CONFIG_MEM_ALLOC_PROFILING_DEBUG is set, kernel WARN would be
triggered when calling __alloc_tag_ref_set() during swap:
alloc_tag was not cleared (got tag for mm/filemap.c:1951)
WARNING: CPU: 0 PID: 816 at ./include/linux/alloc_tag.h...
Clear code tags before swap can fix the warning. And this patch also fix
a potential invalid address dereference in alloc_tag_add_check() when
CONFIG_MEM_ALLOC_PROFILING_DEBUG is set and ref->ct is CODETAG_EMPTY,
which is defined as ((void *)1).
Link: https://lkml.kernel.org/r/20241213013332.89910-1-00107082@163.com
Fixes: 51f43d5d82ed ("mm/codetag: swap tags when migrate pages")
Signed-off-by: David Wang <00107082@163.com>
Reported-by: kernel test robot <oliver.sang@intel.com>
Closes: https://lore.kernel.org/oe-lkp/202412112227.df61ebb-lkp@intel.com
Acked-by: Suren Baghdasaryan <surenb@google.com>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Cc: Yu Zhao <yuzhao@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Fix the following clang compiler warning that is reported if the kernel is
built with W=1:
./include/linux/vmstat.h:518:36: error: arithmetic between different enumeration types ('enum node_stat_item' and 'enum lru_list') [-Werror,-Wenum-enum-conversion]
518 | return node_stat_name(NR_LRU_BASE + lru) + 3; // skip "nr_"
| ~~~~~~~~~~~ ^ ~~~
Link: https://lkml.kernel.org/r/20241212213126.1269116-1-bvanassche@acm.org
Fixes: 9d7ea9a297e6 ("mm/vmstat: add helpers to get vmstat item names for each enum type")
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Other page flags in the 2nd page, like PG_hwpoison and PG_anon_exclusive
can get modified concurrently. Changes to other page flags might be lost
if they are happening at the same time as non-atomic partially_mapped
operations. Hence, make partially_mapped operations atomic.
Link: https://lkml.kernel.org/r/20241212183351.1345389-1-usamaarif642@gmail.com
Fixes: 8422acdc97ed ("mm: introduce a pageflag for partially mapped folios")
Reported-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/all/e53b04ad-1827-43a2-a1ab-864c7efecf6e@redhat.com/
Signed-off-by: Usama Arif <usamaarif642@gmail.com>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Barry Song <baohua@kernel.org>
Cc: Domenico Cerasuolo <cerasuolodomenico@gmail.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mike Rapoport (Microsoft) <rppt@kernel.org>
Cc: Nico Pache <npache@redhat.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Yu Zhao <yuzhao@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Some architectures have special handling after clearing user folios:
architectures, which set cpu_dcache_is_aliasing() to true, require
flushing dcache; arc, which sets cpu_icache_is_aliasing() to true, changes
folio->flags to make icache coherent to dcache. So __GFP_ZERO using only
clear_page() is not enough to zero user folios and clear_user_(high)page()
must be used. Otherwise, user data will be corrupted.
Fix it by always clearing user folios with clear_user_(high)page() when
cpu_dcache_is_aliasing() is true or cpu_icache_is_aliasing() is true.
Rename alloc_zeroed() to user_alloc_needs_zeroing() and invert the logic
to clarify its intend.
Link: https://lkml.kernel.org/r/20241209182326.2955963-2-ziy@nvidia.com
Fixes: 5708d96da20b ("mm: avoid zeroing user movable page twice with init_on_alloc=1")
Signed-off-by: Zi Yan <ziy@nvidia.com>
Reported-by: Geert Uytterhoeven <geert+renesas@glider.be>
Closes: https://lore.kernel.org/linux-mm/CAMuHMdV1hRp_NtR5YnJo=HsfgKQeH91J537Gh4gKk3PFZhSkbA@mail.gmail.com/
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Alexander Potapenko <glider@google.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Vineet Gupta <vgupta@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
In commit eacd0e950dc2 ("ARC: [mm] Lazy D-cache flush (non aliasing
VIPT)"), arc adds the need to flush dcache to make icache see the code
page change. This also requires special handling for
clear_user_(high)page(). Introduce cpu_icache_is_aliasing() to make MM
code query special clear_user_(high)page() easier. This will be used by
the following commit.
Link: https://lkml.kernel.org/r/20241209182326.2955963-1-ziy@nvidia.com
Fixes: 5708d96da20b ("mm: avoid zeroing user movable page twice with init_on_alloc=1")
Signed-off-by: Zi Yan <ziy@nvidia.com>
Suggested-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Alexander Potapenko <glider@google.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Vineet Gupta <vgupta@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
RCU lock is taken by ___pte_offset_map() unless it returns NULL. Add this
information to its inline callers to avoid sparse warning about context
imbalance in pte_unmap().
Link: https://lkml.kernel.org/r/20241210000604.700710-1-oss@malat.biz
Signed-off-by: Petr Malat <oss@malat.biz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Currently, io_uring_unreg_ringfd() (which cleans up registered rings) is
only called on exit, but __io_uring_free (which frees the tctx in which the
registered ring pointers are stored) is also called on execve (via
begin_new_exec -> io_uring_task_cancel -> __io_uring_cancel ->
io_uring_cancel_generic -> __io_uring_free).
This means: A process going through execve while having registered rings
will leak references to the rings' `struct file`.
Fix it by zapping registered rings on execve(). This is implemented by
moving the io_uring_unreg_ringfd() from io_uring_files_cancel() into its
callee __io_uring_cancel(), which is called from io_uring_task_cancel() on
execve.
This could probably be exploited *on 32-bit kernels* by leaking 2^32
references to the same ring, because the file refcount is stored in a
pointer-sized field and get_file() doesn't have protection against
refcount overflow, just a WARN_ONCE(); but on 64-bit it should have no
impact beyond a memory leak.
Cc: stable@vger.kernel.org
Fixes: e7a6c00dc77a ("io_uring: add support for registering ring file descriptors")
Signed-off-by: Jann Horn <jannh@google.com>
Link: https://lore.kernel.org/r/20241218-uring-reg-ring-cleanup-v1-1-8f63e999045b@google.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull tracing fixes from Steven Rostedt:
"Replace trace_check_vprintf() with test_event_printk() and
ignore_event()
The function test_event_printk() checks on boot up if the trace event
printf() formats dereference any pointers, and if they do, it then
looks at the arguments to make sure that the pointers they dereference
will exist in the event on the ring buffer. If they do not, it issues
a WARN_ON() as it is a likely bug.
But this isn't the case for the strings that can be dereferenced with
"%s", as some trace events (notably RCU and some IPI events) save a
pointer to a static string in the ring buffer. As the string it points
to lives as long as the kernel is running, it is not a bug to
reference it, as it is guaranteed to be there when the event is read.
But it is also possible (and a common bug) to point to some allocated
string that could be freed before the trace event is read and the
dereference is to bad memory. This case requires a run time check.
The previous way to handle this was with trace_check_vprintf() that
would process the printf format piece by piece and send what it didn't
care about to vsnprintf() to handle arguments that were not strings.
This kept it from having to reimplement vsnprintf(). But it relied on
va_list implementation and for architectures that copied the va_list
and did not pass it by reference, it wasn't even possible to do this
check and it would be skipped. As 64bit x86 passed va_list by
reference, most events were tested and this kept out bugs where
strings would have been dereferenced after being freed.
Instead of relying on the implementation of va_list, extend the boot
up test_event_printk() function to validate all the "%s" strings that
can be validated at boot, and for the few events that point to strings
outside the ring buffer, flag both the event and the field that is
dereferenced as "needs_test". Then before the event is printed, a call
to ignore_event() is made, and if the event has the flag set, it
iterates all its fields and for every field that is to be tested, it
will read the pointer directly from the event in the ring buffer and
make sure that it is valid. If the pointer is not valid, it will print
a WARN_ON(), print out to the trace that the event has unsafe memory
and ignore the print format.
With this new update, the trace_check_vprintf() can be safely removed
and now all events can be verified regardless of architecture"
* tag 'trace-v6.13-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
tracing: Check "%s" dereference via the field and not the TP_printk format
tracing: Add "%s" check in test_event_printk()
tracing: Add missing helper functions in event pointer dereference check
tracing: Fix test_event_printk() to process entire print argument
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux
Pull hyperv fixes from Wei Liu:
- Various fixes to Hyper-V tools in the kernel tree (Dexuan Cui, Olaf
Hering, Vitaly Kuznetsov)
- Fix a bug in the Hyper-V TSC page based sched_clock() (Naman Jain)
- Two bug fixes in the Hyper-V utility functions (Michael Kelley)
- Convert open-coded timeouts to secs_to_jiffies() in Hyper-V drivers
(Easwar Hariharan)
* tag 'hyperv-fixes-signed-20241217' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux:
tools/hv: reduce resource usage in hv_kvp_daemon
tools/hv: add a .gitignore file
tools/hv: reduce resouce usage in hv_get_dns_info helper
hv/hv_kvp_daemon: Pass NIC name to hv_get_dns_info as well
Drivers: hv: util: Avoid accessing a ringbuffer not initialized yet
Drivers: hv: util: Don't force error code to ENODEV in util_probe()
tools/hv: terminate fcopy daemon if read from uio fails
drivers: hv: Convert open-coded timeouts to secs_to_jiffies()
tools: hv: change permissions of NetworkManager configuration file
x86/hyperv: Fix hv tsc page based sched_clock for hibernation
tools: hv: Fix a complier warning in the fcopy uio daemon
|
|
In 32-bit x86 builds CONFIG_STATIC_CALL_INLINE isn't set, leading to
static_call_initialized not being available.
Define it as "0" in that case.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Fixes: 0ef8047b737d ("x86/static-call: provide a way to do very early static-call updates")
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
The x86_match_cpu() infrastructure can match CPU steppings. Since
there are only 16 possible steppings, the matching infrastructure goes
all out and stores the stepping match as a bitmap. That means it can
match any possible steppings in a single list entry. Fun.
But it exposes this bitmap to each of the X86_MATCH_*() helpers when
none of them really need a bitmap. It makes up for this by exporting a
helper (X86_STEPPINGS()) which converts a contiguous stepping range
into the bitmap which every single user leverages.
Instead of a bitmap, have the main helper for this sort of thing
(X86_MATCH_VFM_STEPS()) just take a stepping range. This ends up
actually being even more compact than before.
Leave the helper in place (renamed to __X86_STEPPINGS()) to make it
more clear what is going on instead of just having a random GENMASK()
in the middle of an already complicated macro.
One oddity that I hit was this macro:
X86_MATCH_VFM_STEPS(vfm, X86_STEPPING_MIN, max_stepping, issues)
It *could* have been converted over to take a min/max stepping value
for each entry. But that would have been a bit too verbose and would
prevent the one oddball in the list (INTEL_COMETLAKE_L stepping 0)
from sticking out.
Instead, just have it take a *maximum* stepping and imply that the match
is from 0=>max_stepping. This is functional for all the cases now and
also retains the nice property of having INTEL_COMETLAKE_L stepping 0
stick out like a sore thumb.
skx_cpuids[] is goofy. It uses the stepping match but encodes all
possible steppings. Just use a normal, non-stepping match helper.
Suggested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://lore.kernel.org/all/20241213185129.65527B2A%40davehans-spike.ostc.intel.com
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git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull hardening fix from Kees Cook:
"Silence a GCC value-range warning that is being ironically triggered
by bounds checking"
* tag 'hardening-v6.13-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
fortify: Hide run-time copy size from value range tracking
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The TP_printk() portion of a trace event is executed at the time a event
is read from the trace. This can happen seconds, minutes, hours, days,
months, years possibly later since the event was recorded. If the print
format contains a dereference to a string via "%s", and that string was
allocated, there's a chance that string could be freed before it is read
by the trace file.
To protect against such bugs, there are two functions that verify the
event. The first one is test_event_printk(), which is called when the
event is created. It reads the TP_printk() format as well as its arguments
to make sure nothing may be dereferencing a pointer that was not copied
into the ring buffer along with the event. If it is, it will trigger a
WARN_ON().
For strings that use "%s", it is not so easy. The string may not reside in
the ring buffer but may still be valid. Strings that are static and part
of the kernel proper which will not be freed for the life of the running
system, are safe to dereference. But to know if it is a pointer to a
static string or to something on the heap can not be determined until the
event is triggered.
This brings us to the second function that tests for the bad dereferencing
of strings, trace_check_vprintf(). It would walk through the printf format
looking for "%s", and when it finds it, it would validate that the pointer
is safe to read. If not, it would produces a WARN_ON() as well and write
into the ring buffer "[UNSAFE-MEMORY]".
The problem with this is how it used va_list to have vsnprintf() handle
all the cases that it didn't need to check. Instead of re-implementing
vsnprintf(), it would make a copy of the format up to the %s part, and
call vsnprintf() with the current va_list ap variable, where the ap would
then be ready to point at the string in question.
For architectures that passed va_list by reference this was possible. For
architectures that passed it by copy it was not. A test_can_verify()
function was used to differentiate between the two, and if it wasn't
possible, it would disable it.
Even for architectures where this was feasible, it was a stretch to rely
on such a method that is undocumented, and could cause issues later on
with new optimizations of the compiler.
Instead, the first function test_event_printk() was updated to look at
"%s" as well. If the "%s" argument is a pointer outside the event in the
ring buffer, it would find the field type of the event that is the problem
and mark the structure with a new flag called "needs_test". The event
itself will be marked by TRACE_EVENT_FL_TEST_STR to let it be known that
this event has a field that needs to be verified before the event can be
printed using the printf format.
When the event fields are created from the field type structure, the
fields would copy the field type's "needs_test" value.
Finally, before being printed, a new function ignore_event() is called
which will check if the event has the TEST_STR flag set (if not, it
returns false). If the flag is set, it then iterates through the events
fields looking for the ones that have the "needs_test" flag set.
Then it uses the offset field from the field structure to find the pointer
in the ring buffer event. It runs the tests to make sure that pointer is
safe to print and if not, it triggers the WARN_ON() and also adds to the
trace output that the event in question has an unsafe memory access.
The ignore_event() makes the trace_check_vprintf() obsolete so it is
removed.
Link: https://lore.kernel.org/all/CAHk-=wh3uOnqnZPpR0PeLZZtyWbZLboZ7cHLCKRWsocvs9Y7hQ@mail.gmail.com/
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>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/20241217024720.848621576@goodmis.org
Fixes: 5013f454a352c ("tracing: Add check of trace event print fmts for dereferencing pointers")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull xen fixes from Juergen Gross:
"Fix xen netfront crash (XSA-465) and avoid using the hypercall page
that doesn't do speculation mitigations (XSA-466)"
* tag 'xsa465+xsa466-6.13-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
x86/xen: remove hypercall page
x86/xen: use new hypercall functions instead of hypercall page
x86/xen: add central hypercall functions
x86/xen: don't do PV iret hypercall through hypercall page
x86/static-call: provide a way to do very early static-call updates
objtool/x86: allow syscall instruction
x86: make get_cpu_vendor() accessible from Xen code
xen/netfront: fix crash when removing device
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Chase reports that their tester complaints about a locking context
mismatch:
=============================
[ BUG: Invalid wait context ]
6.13.0-rc1-gf137f14b7ccb-dirty #9 Not tainted
-----------------------------
syz.1.25198/182604 is trying to lock:
ffff88805e66a358 (&ctx->timeout_lock){-.-.}-{3:3}, at: spin_lock_irq
include/linux/spinlock.h:376 [inline]
ffff88805e66a358 (&ctx->timeout_lock){-.-.}-{3:3}, at:
io_match_task_safe io_uring/io_uring.c:218 [inline]
ffff88805e66a358 (&ctx->timeout_lock){-.-.}-{3:3}, at:
io_match_task_safe+0x187/0x250 io_uring/io_uring.c:204
other info that might help us debug this:
context-{5:5}
1 lock held by syz.1.25198/182604:
#0: ffff88802b7d48c0 (&acct->lock){+.+.}-{2:2}, at:
io_acct_cancel_pending_work+0x2d/0x6b0 io_uring/io-wq.c:1049
stack backtrace:
CPU: 0 UID: 0 PID: 182604 Comm: syz.1.25198 Not tainted
6.13.0-rc1-gf137f14b7ccb-dirty #9
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x82/0xd0 lib/dump_stack.c:120
print_lock_invalid_wait_context kernel/locking/lockdep.c:4826 [inline]
check_wait_context kernel/locking/lockdep.c:4898 [inline]
__lock_acquire+0x883/0x3c80 kernel/locking/lockdep.c:5176
lock_acquire.part.0+0x11b/0x370 kernel/locking/lockdep.c:5849
__raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline]
_raw_spin_lock_irq+0x36/0x50 kernel/locking/spinlock.c:170
spin_lock_irq include/linux/spinlock.h:376 [inline]
io_match_task_safe io_uring/io_uring.c:218 [inline]
io_match_task_safe+0x187/0x250 io_uring/io_uring.c:204
io_acct_cancel_pending_work+0xb8/0x6b0 io_uring/io-wq.c:1052
io_wq_cancel_pending_work io_uring/io-wq.c:1074 [inline]
io_wq_cancel_cb+0xb0/0x390 io_uring/io-wq.c:1112
io_uring_try_cancel_requests+0x15e/0xd70 io_uring/io_uring.c:3062
io_uring_cancel_generic+0x6ec/0x8c0 io_uring/io_uring.c:3140
io_uring_files_cancel include/linux/io_uring.h:20 [inline]
do_exit+0x494/0x27a0 kernel/exit.c:894
do_group_exit+0xb3/0x250 kernel/exit.c:1087
get_signal+0x1d77/0x1ef0 kernel/signal.c:3017
arch_do_signal_or_restart+0x79/0x5b0 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x150/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xd8/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
which is because io_uring has ctx->timeout_lock nesting inside the
io-wq acct lock, the latter of which is used from inside the scheduler
and hence is a raw spinlock, while the former is a "normal" spinlock
and can hence be sleeping on PREEMPT_RT.
Change ctx->timeout_lock to be a raw spinlock to solve this nesting
dependency on PREEMPT_RT=y.
Reported-by: chase xd <sl1589472800@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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