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22881 Commits
Author | SHA1 | Message | Date | |
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Linus Torvalds
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bdf56c7580 |
slab updates for 6.12
-----BEGIN PGP SIGNATURE----- iQEzBAABCAAdFiEEe7vIQRWZI0iWSE3xu+CwddJFiJoFAmbn5g0ACgkQu+CwddJF iJq+Uwf/aqnLNEpjUBzwUUhSojCpPnTtiyjv+AILTxoSTHmbu8OvN0W79+Rpbdmk O4QapAK+BCs+VL2VATwCCufcJ75Z78txO+buQE0DgwluFTIYZ+IwpUMPsK04ln6A FD1/uvP1QFx60heqcp2c4zWFBUpg4DE6ufx2A5kieO268lFcWLxyVlcdgRU79ZCt uAcV2yDLk3GvPGfxZwPKEmZUo/FmuSoBv0XgT+eWxmTu/R7hcpFse49OyjBH8Tvb 8d/RCIFgXOr8dTIjtds7eenwB/is4TkRlctezEQ0jO9/JwL/BVOgXZjD1qCtNWqz is4TWK7VV+vdq1RD+0xC2hV/+uGEwQ== =+WAm -----END PGP SIGNATURE----- Merge tag 'slab-for-6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab Pull slab updates from Vlastimil Babka: "This time it's mostly refactoring and improving APIs for slab users in the kernel, along with some debugging improvements. - kmem_cache_create() refactoring (Christian Brauner) Over the years have been growing new parameters to kmem_cache_create() where most of them are needed only for a small number of caches - most recently the rcu_freeptr_offset parameter. To avoid adding new parameters to kmem_cache_create() and adjusting all its callers, or creating new wrappers such as kmem_cache_create_rcu(), we can now pass extra parameters using the new struct kmem_cache_args. Not explicitly initialized fields default to values interpreted as unused. kmem_cache_create() is for now a wrapper that works both with the new form: kmem_cache_create(name, object_size, args, flags) and the legacy form: kmem_cache_create(name, object_size, align, flags, ctor) - kmem_cache_destroy() waits for kfree_rcu()'s in flight (Vlastimil Babka, Uladislau Rezki) Since SLOB removal, kfree() is allowed for freeing objects allocated by kmem_cache_create(). By extension kfree_rcu() as allowed as well, which can allow converting simple call_rcu() callbacks that only do kmem_cache_free(), as there was never a kmem_cache_free_rcu() variant. However, for caches that can be destroyed e.g. on module removal, the cache owners knew to issue rcu_barrier() first to wait for the pending call_rcu()'s, and this is not sufficient for pending kfree_rcu()'s due to its internal batching optimizations. Ulad has provided a new kvfree_rcu_barrier() and to make the usage less error-prone, kmem_cache_destroy() calls it. Additionally, destroying SLAB_TYPESAFE_BY_RCU caches now again issues rcu_barrier() synchronously instead of using an async work, because the past motivation for async work no longer applies. Users of custom call_rcu() callbacks should however keep calling rcu_barrier() before cache destruction. - Debugging use-after-free in SLAB_TYPESAFE_BY_RCU caches (Jann Horn) Currently, KASAN cannot catch UAFs in such caches as it is legal to access them within a grace period, and we only track the grace period when trying to free the underlying slab page. The new CONFIG_SLUB_RCU_DEBUG option changes the freeing of individual object to be RCU-delayed, after which KASAN can poison them. - Delayed memcg charging (Shakeel Butt) In some cases, the memcg is uknown at allocation time, such as receiving network packets in softirq context. With kmem_cache_charge() these may be now charged later when the user and its memcg is known. - Misc fixes and improvements (Pedro Falcato, Axel Rasmussen, Christoph Lameter, Yan Zhen, Peng Fan, Xavier)" * tag 'slab-for-6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab: (34 commits) mm, slab: restore kerneldoc for kmem_cache_create() io_uring: port to struct kmem_cache_args slab: make __kmem_cache_create() static inline slab: make kmem_cache_create_usercopy() static inline slab: remove kmem_cache_create_rcu() file: port to struct kmem_cache_args slab: create kmem_cache_create() compatibility layer slab: port KMEM_CACHE_USERCOPY() to struct kmem_cache_args slab: port KMEM_CACHE() to struct kmem_cache_args slab: remove rcu_freeptr_offset from struct kmem_cache slab: pass struct kmem_cache_args to do_kmem_cache_create() slab: pull kmem_cache_open() into do_kmem_cache_create() slab: pass struct kmem_cache_args to create_cache() slab: port kmem_cache_create_usercopy() to struct kmem_cache_args slab: port kmem_cache_create_rcu() to struct kmem_cache_args slab: port kmem_cache_create() to struct kmem_cache_args slab: add struct kmem_cache_args slab: s/__kmem_cache_create/do_kmem_cache_create/g memcg: add charging of already allocated slab objects mm/slab: Optimize the code logic in find_mergeable() ... |
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Linus Torvalds
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adfc3ded5c |
for-6.12/io_uring-discard-20240913
-----BEGIN PGP SIGNATURE----- iQJEBAABCAAuFiEEwPw5LcreJtl1+l5K99NY+ylx4KYFAmbkboUQHGF4Ym9lQGtl cm5lbC5kawAKCRD301j7KXHgpj7DD/oDqQ13NOHuotVbufPRDWuG6+UEaN/Pukp/ RYDWwYu/DB4v7LVWBV9COqN5jQqY2wrMpgBdZqtEnDtC7yjN6QYAT4TQdfIq/HNo NooN4ULmJzOOC6sR9MBGyzOsCbz7kmRt1nBZ7vdEXMrLXeX9JDX3bDrELf7jhKsk 84lKE/Mxs530LSzxAtN9KaOQncK5gXen4WSrZsYraU2vJFAPBkJwQGAL5pOdmsp9 NqvNE3QonPr4v99XnDJH80q44afuqffUITPjtGX52tBMO3CCUQFUpZp5fiUjfa1v Okz+SyeBE6gB7c008BGqTOgmKdQOMs3uwFDQ/xMw+pYwy+wHH4skzPP776DwAdgn C/SaVFsaXkqOXX4f+CiNJ01LmD4EOBy16LM5qE4NwLNpjQu/3EdHjNqaYfM/LCca YyQoUOsnYIRj21+oNFpKekscuEAPKG9ewyMyvfxbkk167j00lgwVwybb/2JfYvRJ i0GBY5phJnkeNUerU9SDm6RBTAjDOZ0stubTtFjugDZdrz2FmA4pBFGWjgYLiLhH 3ZCyaCAOoYW8yxxkogTzKbLx6wXb5wgS7jTHgsk+eeSSWRBTnv2sd0fn/D5m3Uw7 uBHKvauDp3zEd9MdF26QG7U6RlojEbVoyTYjnJskPsClxbch4WSpwvoEILdJRvls 1dTczxgdyw== =wlzo -----END PGP SIGNATURE----- Merge tag 'for-6.12/io_uring-discard-20240913' of git://git.kernel.dk/linux Pull io_uring async discard support from Jens Axboe: "Sitting on top of both the 6.12 block and io_uring core branches, here's support for async discard through io_uring. This allows applications to issue async discards, rather than rely on the blocking sync ioctl discards we already have. The sync support is difficult to use outside of idle/cleanup periods. On a real (but slow) device, testing shows the following results when compared to sync discard: qd64 sync discard: 21K IOPS, lat avg 3 msec (max 21 msec) qd64 async discard: 76K IOPS, lat avg 845 usec (max 2.2 msec) qd64 sync discard: 14K IOPS, lat avg 5 msec (max 25 msec) qd64 async discard: 56K IOPS, lat avg 1153 usec (max 3.6 msec) and synthetic null_blk testing with the same queue depth and block size settings as above shows: Type Trim size IOPS Lat avg (usec) Lat Max (usec) ============================================================== sync 4k 144K 444 20314 async 4k 1353K 47 595 sync 1M 56K 1136 21031 async 1M 94K 680 760" * tag 'for-6.12/io_uring-discard-20240913' of git://git.kernel.dk/linux: block: implement async io_uring discard cmd block: introduce blk_validate_byte_range() filemap: introduce filemap_invalidate_pages io_uring/cmd: give inline space in request to cmds io_uring/cmd: expose iowq to cmds |
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Linus Torvalds
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26bb0d3f38 |
for-6.12/block-20240913
-----BEGIN PGP SIGNATURE----- iQJEBAABCAAuFiEEwPw5LcreJtl1+l5K99NY+ylx4KYFAmbkZhQQHGF4Ym9lQGtl cm5lbC5kawAKCRD301j7KXHgpjOKD/0fzd4yOcqxSI9W3OLGd04VrOTJIQa4CRbV GmoTq39pOeIDVGug5ekkTpqqHHnuGk+nQhCzD9vsN/eTmC7yZOIr847O2aWzvYEn PzFRgmJpoo2E9sr/IsTR5LnJjbaIZhQVkqLH6ZOj9tpKlVwN2SK0nIRVNrAi5zgT MaDrto/2OUld+vmA99Rgb23jxM6UBdCPIjuiVa+11Vg9Z3D1tWbBmrsG7OMysyIf FbASBeKHqFSO61/ipFCZv6VV1X8zoWEVyT8n4A1yUbbN5rLzPgoQJVbfSqQRXIdr cdrKeCbKxl+joSgKS6LKpvnfwRgGF+hgAfpZg4c0vrbZGTQcRhhLFECyh/aVI08F p5TOMArhVaX59664gHgSPq4KnGTXOO29dot9N3Jya/ZQnxinjY9r+GVOfLuduPPy 1B04vab8oAsk4zK7fZbkDxgYUyifwzK/vQ6OqYq2mYdpdIS/AE7T2ou61Bz5mI7I /BuucNV0Z96OKlyLEXwXXZjZgNu1TFcq6ARIBJ8L08PY64Fesj5BXabRyXkeNH26 0exyz9heeJs6OwRGfngXmS24tDSS0k74CeZX3KoePNj69u6KCn346KiU1qgntwwD E5F7AEHqCl5FjUEIWB4M1EPlfA8U0MzOL+tkx2xKJAjsU60wAy7jRSyOIcqodpMs 6UlPcJzgYg== =uuLl -----END PGP SIGNATURE----- Merge tag 'for-6.12/block-20240913' of git://git.kernel.dk/linux Pull block updates from Jens Axboe: - MD changes via Song: - md-bitmap refactoring (Yu Kuai) - raid5 performance optimization (Artur Paszkiewicz) - Other small fixes (Yu Kuai, Chen Ni) - Add a sysfs entry 'new_level' (Xiao Ni) - Improve information reported in /proc/mdstat (Mateusz Kusiak) - NVMe changes via Keith: - Asynchronous namespace scanning (Stuart) - TCP TLS updates (Hannes) - RDMA queue controller validation (Niklas) - Align field names to the spec (Anuj) - Metadata support validation (Puranjay) - A syntax cleanup (Shen) - Fix a Kconfig linking error (Arnd) - New queue-depth quirk (Keith) - Add missing unplug trace event (Keith) - blk-iocost fixes (Colin, Konstantin) - t10-pi modular removal and fixes (Alexey) - Fix for potential BLKSECDISCARD overflow (Alexey) - bio splitting cleanups and fixes (Christoph) - Deal with folios rather than rather than pages, speeding up how the block layer handles bigger IOs (Kundan) - Use spinlocks rather than bit spinlocks in zram (Sebastian, Mike) - Reduce zoned device overhead in ublk (Ming) - Add and use sendpages_ok() for drbd and nvme-tcp (Ofir) - Fix regression in partition error pointer checking (Riyan) - Add support for write zeroes and rotational status in nbd (Wouter) - Add Yu Kuai as new BFQ maintainer. The scheduler has been unmaintained for quite a while. - Various sets of fixes for BFQ (Yu Kuai) - Misc fixes and cleanups (Alvaro, Christophe, Li, Md Haris, Mikhail, Yang) * tag 'for-6.12/block-20240913' of git://git.kernel.dk/linux: (120 commits) nvme-pci: qdepth 1 quirk block: fix potential invalid pointer dereference in blk_add_partition blk_iocost: make read-only static array vrate_adj_pct const block: unpin user pages belonging to a folio at once mm: release number of pages of a folio block: introduce folio awareness and add a bigger size from folio block: Added folio-ized version of bio_add_hw_page() block, bfq: factor out a helper to split bfqq in bfq_init_rq() block, bfq: remove local variable 'bfqq_already_existing' in bfq_init_rq() block, bfq: remove local variable 'split' in bfq_init_rq() block, bfq: remove bfq_log_bfqg() block, bfq: merge bfq_release_process_ref() into bfq_put_cooperator() block, bfq: fix procress reference leakage for bfqq in merge chain block, bfq: fix uaf for accessing waker_bfqq after splitting blk-throttle: support prioritized processing of metadata blk-throttle: remove last_low_overflow_time drbd: Add NULL check for net_conf to prevent dereference in state validation nvme-tcp: fix link failure for TCP auth blk-mq: add missing unplug trace event mtip32xx: Remove redundant null pointer checks in mtip_hw_debugfs_init() ... |
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Linus Torvalds
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3352633ce6 |
vfs-6.12.file
-----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCZuQEwAAKCRCRxhvAZXjc osS0AQCgIpvey9oW5DMyMw6Bv0hFMRv95gbNQZfHy09iK+NMNAD9GALhb/4cMIVB 7YrZGXEz454lpgcs8AnrOVjVNfctOQg= =e9s9 -----END PGP SIGNATURE----- Merge tag 'vfs-6.12.file' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull vfs file updates from Christian Brauner: "This is the work to cleanup and shrink struct file significantly. Right now, (focusing on x86) struct file is 232 bytes. After this series struct file will be 184 bytes aka 3 cacheline and a spare 8 bytes for future extensions at the end of the struct. With struct file being as ubiquitous as it is this should make a difference for file heavy workloads and allow further optimizations in the future. - struct fown_struct was embedded into struct file letting it take up 32 bytes in total when really it shouldn't even be embedded in struct file in the first place. Instead, actual users of struct fown_struct now allocate the struct on demand. This frees up 24 bytes. - Move struct file_ra_state into the union containg the cleanup hooks and move f_iocb_flags out of the union. This closes a 4 byte hole we created earlier and brings struct file to 192 bytes. Which means struct file is 3 cachelines and we managed to shrink it by 40 bytes. - Reorder struct file so that nothing crosses a cacheline. I suspect that in the future we will end up reordering some members to mitigate false sharing issues or just because someone does actually provide really good perf data. - Shrinking struct file to 192 bytes is only part of the work. Files use a slab that is SLAB_TYPESAFE_BY_RCU and when a kmem cache is created with SLAB_TYPESAFE_BY_RCU the free pointer must be located outside of the object because the cache doesn't know what part of the memory can safely be overwritten as it may be needed to prevent object recycling. That has the consequence that SLAB_TYPESAFE_BY_RCU may end up adding a new cacheline. So this also contains work to add a new kmem_cache_create_rcu() function that allows the caller to specify an offset where the freelist pointer is supposed to be placed. Thus avoiding the implicit addition of a fourth cacheline. - And finally this removes the f_version member in struct file. The f_version member isn't particularly well-defined. It is mainly used as a cookie to detect concurrent seeks when iterating directories. But it is also abused by some subsystems for completely unrelated things. It is mostly a directory and filesystem specific thing that doesn't really need to live in struct file and with its wonky semantics it really lacks a specific function. For pipes, f_version is (ab)used to defer poll notifications until a write has happened. And struct pipe_inode_info is used by multiple struct files in their ->private_data so there's no chance of pushing that down into file->private_data without introducing another pointer indirection. But pipes don't rely on f_pos_lock so this adds a union into struct file encompassing f_pos_lock and a pipe specific f_pipe member that pipes can use. This union of course can be extended to other file types and is similar to what we do in struct inode already" * tag 'vfs-6.12.file' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (26 commits) fs: remove f_version pipe: use f_pipe fs: add f_pipe ubifs: store cookie in private data ufs: store cookie in private data udf: store cookie in private data proc: store cookie in private data ocfs2: store cookie in private data input: remove f_version abuse ext4: store cookie in private data ext2: store cookie in private data affs: store cookie in private data fs: add generic_llseek_cookie() fs: use must_set_pos() fs: add must_set_pos() fs: add vfs_setpos_cookie() s390: remove unused f_version ceph: remove unused f_version adi: remove unused f_version mm: Removed @freeptr_offset to prevent doc warning ... |
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Linus Torvalds
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2775df6e5e |
vfs-6.12.folio
-----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCZuQEvgAKCRCRxhvAZXjc ou77AQD3U1KjbdgzbUi6kaUmiiWOPhfYTlm8mho8dBjqvTCB+AD/XTWSFCWWhHB4 KyQZTbjRD81xmVNbKjASazp0EA6Ahwc= =gIsD -----END PGP SIGNATURE----- Merge tag 'vfs-6.12.folio' of gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs Pull vfs folio updates from Christian Brauner: "This contains work to port write_begin and write_end to rely on folios for various filesystems. This converts ocfs2, vboxfs, orangefs, jffs2, hostfs, fuse, f2fs, ecryptfs, ntfs3, nilfs2, reiserfs, minixfs, qnx6, sysv, ufs, and squashfs. After this series lands a bunch of the filesystems in this list do not mention struct page anymore" * tag 'vfs-6.12.folio' of gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs: (61 commits) Squashfs: Ensure all readahead pages have been used Squashfs: Rewrite and update squashfs_readahead_fragment() to not use page->index Squashfs: Update squashfs_readpage_block() to not use page->index Squashfs: Update squashfs_readahead() to not use page->index Squashfs: Update page_actor to not use page->index jffs2: Use a folio in jffs2_garbage_collect_dnode() jffs2: Convert jffs2_do_readpage_nolock to take a folio buffer: Convert __block_write_begin() to take a folio ocfs2: Convert ocfs2_write_zero_page to use a folio fs: Convert aops->write_begin to take a folio fs: Convert aops->write_end to take a folio vboxsf: Use a folio in vboxsf_write_end() orangefs: Convert orangefs_write_begin() to use a folio orangefs: Convert orangefs_write_end() to use a folio jffs2: Convert jffs2_write_begin() to use a folio jffs2: Convert jffs2_write_end() to use a folio hostfs: Convert hostfs_write_end() to use a folio fuse: Convert fuse_write_begin() to use a folio fuse: Convert fuse_write_end() to use a folio f2fs: Convert f2fs_write_begin() to use a folio ... |
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Linus Torvalds
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8f72c31f45 |
vfs-6.12.misc
-----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCZuQEGwAKCRCRxhvAZXjc ojIuAQC433+hBkvjvmQ7H0r5rgZSjUuCTG3bSmdU7RJmPHUHhwEA85v/NGq53f+W IhandK6t+Cf0JYpFZ3N0bT88hDYVhQQ= =9zGL -----END PGP SIGNATURE----- Merge tag 'vfs-6.12.misc' of gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs Pull misc vfs updates from Christian Brauner: "This contains the usual pile of misc updates: Features: - Add F_CREATED_QUERY fcntl() that allows userspace to query whether a file was actually created. Often userspace wants to know whether an O_CREATE request did actually create a file without using O_EXCL. The current logic is that to first attempts to open the file without O_CREAT | O_EXCL and if ENOENT is returned userspace tries again with both flags. If that succeeds all is well. If it now reports EEXIST it retries. That works fairly well but some corner cases make this more involved. If this operates on a dangling symlink the first openat() without O_CREAT | O_EXCL will return ENOENT but the second openat() with O_CREAT | O_EXCL will fail with EEXIST. The reason is that openat() without O_CREAT | O_EXCL follows the symlink while O_CREAT | O_EXCL doesn't for security reasons. So it's not something we can really change unless we add an explicit opt-in via O_FOLLOW which seems really ugly. All available workarounds are really nasty (fanotify, bpf lsm etc) so add a simple fcntl(). - Try an opportunistic lookup for O_CREAT. Today, when opening a file we'll typically do a fast lookup, but if O_CREAT is set, the kernel always takes the exclusive inode lock. This was likely done with the expectation that O_CREAT means that we always expect to do the create, but that's often not the case. Many programs set O_CREAT even in scenarios where the file already exists (see related F_CREATED_QUERY patch motivation above). The series contained in the pr rearranges the pathwalk-for-open code to also attempt a fast_lookup in certain O_CREAT cases. If a positive dentry is found, the inode_lock can be avoided altogether and it can stay in rcuwalk mode for the last step_into. - Expose the 64 bit mount id via name_to_handle_at() Now that we provide a unique 64-bit mount ID interface in statx(2), we can now provide a race-free way for name_to_handle_at(2) to provide a file handle and corresponding mount without needing to worry about racing with /proc/mountinfo parsing or having to open a file just to do statx(2). While this is not necessary if you are using AT_EMPTY_PATH and don't care about an extra statx(2) call, users that pass full paths into name_to_handle_at(2) need to know which mount the file handle comes from (to make sure they don't try to open_by_handle_at a file handle from a different filesystem) and switching to AT_EMPTY_PATH would require allocating a file for every name_to_handle_at(2) call - Add a per dentry expire timeout to autofs There are two fairly well known automounter map formats, the autofs format and the amd format (more or less System V and Berkley). Some time ago Linux autofs added an amd map format parser that implemented a fair amount of the amd functionality. This was done within the autofs infrastructure and some functionality wasn't implemented because it either didn't make sense or required extra kernel changes. The idea was to restrict changes to be within the existing autofs functionality as much as possible and leave changes with a wider scope to be considered later. One of these changes is implementing the amd options: 1) "unmount", expire this mount according to a timeout (same as the current autofs default). 2) "nounmount", don't expire this mount (same as setting the autofs timeout to 0 except only for this specific mount) . 3) "utimeout=<seconds>", expire this mount using the specified timeout (again same as setting the autofs timeout but only for this mount) To implement these options per-dentry expire timeouts need to be implemented for autofs indirect mounts. This is because all map keys (mounts) for autofs indirect mounts use an expire timeout stored in the autofs mount super block info. structure and all indirect mounts use the same expire timeout. Fixes: - Fix missing fput for FSCONFIG_SET_FD in autofs - Use param->file for FSCONFIG_SET_FD in coda - Delete the 'fs/netfs' proc subtreee when netfs module exits - Make sure that struct uid_gid_map fits into a single cacheline - Don't flush in-flight wb switches for superblocks without cgroup writeback - Correcting the idmapping mount example in the idmapping documentation - Fix a race between evice_inodes() and find_inode() and iput() - Refine the show_inode_state() macro definition in writeback code - Prevent dump_mapping() from accessing invalid dentry.d_name.name - Show actual source for debugfs in /proc/mounts - Annotate data-race of busy_poll_usecs in eventpoll - Don't WARN for racy path_noexec check in exec code - Handle OOM on mnt_warn_timestamp_expiry() - Fix some spelling in the iomap design documentation - Fix typo in procfs comment - Fix typo in fs/namespace.c comment Cleanups: - Add the VFS git tree to the MAINTAINERS file - Move FMODE_UNSIGNED_OFFSET to fop_flags freeing up another f_mode bit in struct file bringing us to 5 free f_mode bits - Remove the __I_DIO_WAKEUP bit from i_state flags as we can simplify the wait mechanism - Remove the unused path_put_init() helper - Replace a __u32 with u32 for s_fsnotify_mask as __u32 is uapi specific - Replace the unsigned long i_state member with a u32 i_state member in struct inode freeing up 4 bytes in struct inode. Instead of using the bit based wait apis we're now using the var event apis and using the individual bytes of the i_state member to wait on state changes - Explain how per-syscall AT_* flags should be allocated - Use in_group_or_capable() helper to simplify the posix acl mode update code - Switch to LIST_HEAD() in fsync_buffers_list() to simplify the code - Removed comment about d_rcu_to_refcount() as that function doesn't exist anymore - Add kernel documentation for lookup_fast() - Don't re-zero evenpoll fields - Remove outdated comment after close_fd() - Fix imprecise wording in comment about the pipe filesystem - Drop GFP_NOFAIL mode from alloc_page_buffers - Missing blank line warnings and struct declaration improved in file_table - Annotate struct poll_list with __counted_by() - Remove the unused read parameter in percpu-rwsem - Remove linux/prefetch.h include from direct-io code - Use kmemdup_array instead of kmemdup for multiple allocation in mnt_idmapping code - Remove unused mnt_cursor_del() declaration Performance tweaks: - Dodge smp_mb in break_lease and break_deleg in the common case - Only read fops once in fops_{get,put}() - Use RCU in ilookup() - Elide smp_mb in iversion handling in the common case - Drop one lock trip in evict()" * tag 'vfs-6.12.misc' of gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs: (58 commits) uidgid: make sure we fit into one cacheline proc: Fix typo in the comment fs/pipe: Correct imprecise wording in comment fhandle: expose u64 mount id to name_to_handle_at(2) uapi: explain how per-syscall AT_* flags should be allocated fs: drop GFP_NOFAIL mode from alloc_page_buffers writeback: Refine the show_inode_state() macro definition fs/inode: Prevent dump_mapping() accessing invalid dentry.d_name.name mnt_idmapping: Use kmemdup_array instead of kmemdup for multiple allocation netfs: Delete subtree of 'fs/netfs' when netfs module exits fs: use LIST_HEAD() to simplify code inode: make i_state a u32 inode: port __I_LRU_ISOLATING to var event vfs: fix race between evice_inodes() and find_inode()&iput() inode: port __I_NEW to var event inode: port __I_SYNC to var event fs: reorder i_state bits fs: add i_state helpers MAINTAINERS: add the VFS git tree fs: s/__u32/u32/ for s_fsnotify_mask ... |
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Vlastimil Babka
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ecc4d6af97 |
Merge branch 'slab/for-6.12/kmem_cache_args' into slab/for-next
Merge kmem_cache_create() refactoring by Christian Brauner. Note this includes a merge of the vfs.file tree that contains the prerequisity kmem_cache_create_rcu() work. |
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Vlastimil Babka
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a715e94dbd |
Merge branch 'slab/for-6.12/rcu_barriers' into slab/for-next
Merge most of SLUB feature work for 6.12: - Barrier for pending kfree_rcu() in kmem_cache_destroy() and associated refactoring of the destroy path (Vlastimil Babka) - CONFIG_SLUB_RCU_DEBUG to allow KASAN catching UAF bugs in SLAB_TYPESAFE_BY_RCU caches (Jann Horn) - kmem_cache_charge() for delayed kmemcg charging (Shakeel Butt) |
||
Vlastimil Babka
|
4b7ff9ab98 |
mm, slab: restore kerneldoc for kmem_cache_create()
As kmem_cache_create() became a _Generic() wrapper macro, it currently has no kerneldoc despite being the main API to use. Add it. Also adjust kmem_cache_create_usercopy() kerneldoc to indicate it is now a legacy wrapper. Also expand the kerneldoc for struct kmem_cache_args, especially for the freeptr_offset field, where important details were removed with the removal of kmem_cache_create_rcu(). Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Christian Brauner <brauner@kernel.org> |
||
Linus Torvalds
|
79a61cc3fc |
mm: avoid leaving partial pfn mappings around in error case
As Jann points out, PFN mappings are special, because unlike normal memory mappings, there is no lifetime information associated with the mapping - it is just a raw mapping of PFNs with no reference counting of a 'struct page'. That's all very much intentional, but it does mean that it's easy to mess up the cleanup in case of errors. Yes, a failed mmap() will always eventually clean up any partial mappings, but without any explicit lifetime in the page table mapping itself, it's very easy to do the error handling in the wrong order. In particular, it's easy to mistakenly free the physical backing store before the page tables are actually cleaned up and (temporarily) have stale dangling PTE entries. To make this situation less error-prone, just make sure that any partial pfn mapping is torn down early, before any other error handling. Reported-and-tested-by: Jann Horn <jannh@google.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Simona Vetter <simona.vetter@ffwll.ch> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
Pavel Begunkov
|
a12c883a0a |
filemap: introduce filemap_invalidate_pages
kiocb_invalidate_pages() is useful for the write path, however not everything is backed by kiocb and we want to reuse the function for bio based discard implementation. Extract and and reuse a new helper called filemap_invalidate_pages(), which takes a argument indicating whether it should be non-blocking and might return -EAGAIN. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/f81374b52c92d0dce0f01a279d1eed42b54056aa.1726072086.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk> |
||
Jens Axboe
|
318ad4283a |
Merge branch 'for-6.12/block' into for-6.12/io_uring-discard
* for-6.12/block: (115 commits) block: unpin user pages belonging to a folio at once mm: release number of pages of a folio block: introduce folio awareness and add a bigger size from folio block: Added folio-ized version of bio_add_hw_page() block, bfq: factor out a helper to split bfqq in bfq_init_rq() block, bfq: remove local variable 'bfqq_already_existing' in bfq_init_rq() block, bfq: remove local variable 'split' in bfq_init_rq() block, bfq: remove bfq_log_bfqg() block, bfq: merge bfq_release_process_ref() into bfq_put_cooperator() block, bfq: fix procress reference leakage for bfqq in merge chain block, bfq: fix uaf for accessing waker_bfqq after splitting blk-throttle: support prioritized processing of metadata blk-throttle: remove last_low_overflow_time drbd: Add NULL check for net_conf to prevent dereference in state validation blk-mq: add missing unplug trace event mtip32xx: Remove redundant null pointer checks in mtip_hw_debugfs_init() md: Add new_level sysfs interface zram: Shrink zram_table_entry::flags. zram: Remove ZRAM_LOCK zram: Replace bit spinlocks with a spinlock_t. ... |
||
Kundan Kumar
|
d3bfbfb124 |
mm: release number of pages of a folio
Add a new function unpin_user_folio() to put the refs of a folio by npages count. The check for BIO_PAGE_PINNED flag is removed as it is already checked in bio_release_pages(). Signed-off-by: Kundan Kumar <kundan.kumar@samsung.com> Tested-by: Luis Chamberlain <mcgrof@kernel.org> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Link: https://lore.kernel.org/r/20240911064935.5630-4-kundan.kumar@samsung.com Signed-off-by: Jens Axboe <axboe@kernel.dk> |
||
Christian Brauner
|
781aee7556 |
slab: make __kmem_cache_create() static inline
Make __kmem_cache_create() a static inline function. Signed-off-by: Christian Brauner <brauner@kernel.org> Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Reviewed-by: Roman Gushchin <roman.gushchin@linux.dev> Signed-off-by: Vlastimil Babka <vbabka@suse.cz> |
||
Christian Brauner
|
0c9050b09c |
slab: make kmem_cache_create_usercopy() static inline
Make kmem_cache_create_usercopy() a static inline function. Signed-off-by: Christian Brauner <brauner@kernel.org> Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Reviewed-by: Roman Gushchin <roman.gushchin@linux.dev> Signed-off-by: Vlastimil Babka <vbabka@suse.cz> |
||
Christian Brauner
|
3d453e60f1 |
slab: remove kmem_cache_create_rcu()
Now that we have ported all users of kmem_cache_create_rcu() to struct kmem_cache_args the function is unused and can be removed. Reviewed-by: Kees Cook <kees@kernel.org> Reviewed-by: Jens Axboe <axboe@kernel.dk> Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Christian Brauner <brauner@kernel.org> Reviewed-by: Roman Gushchin <roman.gushchin@linux.dev> Signed-off-by: Vlastimil Babka <vbabka@suse.cz> |
||
Christian Brauner
|
b2e7456b5c |
slab: create kmem_cache_create() compatibility layer
Use _Generic() to create a compatibility layer that type switches on the third argument to either call __kmem_cache_create() or __kmem_cache_create_args(). If NULL is passed for the struct kmem_cache_args argument use default args making porting for callers that don't care about additional arguments easy. Reviewed-by: Kees Cook <kees@kernel.org> Reviewed-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Christian Brauner <brauner@kernel.org> Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Reviewed-by: Roman Gushchin <roman.gushchin@linux.dev> Signed-off-by: Vlastimil Babka <vbabka@suse.cz> |
||
Christian Brauner
|
dacf472bcd |
slab: remove rcu_freeptr_offset from struct kmem_cache
Pass down struct kmem_cache_args to calculate_sizes() so we can use args->{use}_freeptr_offset directly. This allows us to remove ->rcu_freeptr_offset from struct kmem_cache. Reviewed-by: Kees Cook <kees@kernel.org> Reviewed-by: Jens Axboe <axboe@kernel.dk> Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Christian Brauner <brauner@kernel.org> Reviewed-by: Roman Gushchin <roman.gushchin@linux.dev> Signed-off-by: Vlastimil Babka <vbabka@suse.cz> |
||
Christian Brauner
|
3dbe2bad57 |
slab: pass struct kmem_cache_args to do_kmem_cache_create()
and initialize most things in do_kmem_cache_create(). In a follow-up patch we'll remove rcu_freeptr_offset from struct kmem_cache. Reviewed-by: Kees Cook <kees@kernel.org> Reviewed-by: Jens Axboe <axboe@kernel.dk> Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Christian Brauner <brauner@kernel.org> Reviewed-by: Roman Gushchin <roman.gushchin@linux.dev> Signed-off-by: Vlastimil Babka <vbabka@suse.cz> |
||
Christian Brauner
|
fc0eac57d0 |
slab: pull kmem_cache_open() into do_kmem_cache_create()
do_kmem_cache_create() is the only caller and we're going to pass down struct kmem_cache_args in a follow-up patch. Reviewed-by: Kees Cook <kees@kernel.org> Reviewed-by: Jens Axboe <axboe@kernel.dk> Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Christian Brauner <brauner@kernel.org> Reviewed-by: Roman Gushchin <roman.gushchin@linux.dev> Signed-off-by: Vlastimil Babka <vbabka@suse.cz> |
||
Christian Brauner
|
34410a9060 |
slab: pass struct kmem_cache_args to create_cache()
Pass struct kmem_cache_args to create_cache() so that we can later simplify further helpers. Reviewed-by: Kees Cook <kees@kernel.org> Reviewed-by: Jens Axboe <axboe@kernel.dk> Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Christian Brauner <brauner@kernel.org> Reviewed-by: Roman Gushchin <roman.gushchin@linux.dev> Signed-off-by: Vlastimil Babka <vbabka@suse.cz> |
||
Christian Brauner
|
1d3d7645d7 |
slab: port kmem_cache_create_usercopy() to struct kmem_cache_args
Port kmem_cache_create_usercopy() to struct kmem_cache_args and remove the now unused do_kmem_cache_create_usercopy() helper. Reviewed-by: Kees Cook <kees@kernel.org> Reviewed-by: Jens Axboe <axboe@kernel.dk> Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Christian Brauner <brauner@kernel.org> Reviewed-by: Roman Gushchin <roman.gushchin@linux.dev> Signed-off-by: Vlastimil Babka <vbabka@suse.cz> |
||
Christian Brauner
|
9816c3c4e7 |
slab: port kmem_cache_create_rcu() to struct kmem_cache_args
Port kmem_cache_create_rcu() to struct kmem_cache_args. Reviewed-by: Kees Cook <kees@kernel.org> Reviewed-by: Jens Axboe <axboe@kernel.dk> Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Christian Brauner <brauner@kernel.org> Reviewed-by: Roman Gushchin <roman.gushchin@linux.dev> Signed-off-by: Vlastimil Babka <vbabka@suse.cz> |
||
Christian Brauner
|
f6cd98c940 |
slab: port kmem_cache_create() to struct kmem_cache_args
Port kmem_cache_create() to struct kmem_cache_args. Reviewed-by: Kees Cook <kees@kernel.org> Reviewed-by: Jens Axboe <axboe@kernel.dk> Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Christian Brauner <brauner@kernel.org> Reviewed-by: Roman Gushchin <roman.gushchin@linux.dev> Signed-off-by: Vlastimil Babka <vbabka@suse.cz> |
||
Christian Brauner
|
879fb3c274 |
slab: add struct kmem_cache_args
Currently we have multiple kmem_cache_create*() variants that take up to seven separate parameters with one of the functions having to grow an eigth parameter in the future to handle both usercopy and a custom freelist pointer. Add a struct kmem_cache_args structure and move less common parameters into it. Core parameters such as name, object size, and flags continue to be passed separately. Add a new function __kmem_cache_create_args() that takes a struct kmem_cache_args pointer and port do_kmem_cache_create_usercopy() over to it. In follow-up patches we will port the other kmem_cache_create*() variants over to it as well. Reviewed-by: Kees Cook <kees@kernel.org> Reviewed-by: Jens Axboe <axboe@kernel.dk> Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Christian Brauner <brauner@kernel.org> Reviewed-by: Roman Gushchin <roman.gushchin@linux.dev> Signed-off-by: Vlastimil Babka <vbabka@suse.cz> |
||
Christian Brauner
|
53d3d21086 |
slab: s/__kmem_cache_create/do_kmem_cache_create/g
Free up reusing the double-underscore variant for follow-up patches. Reviewed-by: Kees Cook <kees@kernel.org> Reviewed-by: Jens Axboe <axboe@kernel.dk> Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Christian Brauner <brauner@kernel.org> Reviewed-by: Roman Gushchin <roman.gushchin@linux.dev> Signed-off-by: Vlastimil Babka <vbabka@suse.cz> |
||
Shakeel Butt
|
9028cdeb38 |
memcg: add charging of already allocated slab objects
At the moment, the slab objects are charged to the memcg at the allocation time. However there are cases where slab objects are allocated at the time where the right target memcg to charge it to is not known. One such case is the network sockets for the incoming connection which are allocated in the softirq context. Couple hundred thousand connections are very normal on large loaded server and almost all of those sockets underlying those connections get allocated in the softirq context and thus not charged to any memcg. However later at the accept() time we know the right target memcg to charge. Let's add new API to charge already allocated objects, so we can have better accounting of the memory usage. To measure the performance impact of this change, tcp_crr is used from the neper [1] performance suite. Basically it is a network ping pong test with new connection for each ping pong. The server and the client are run inside 3 level of cgroup hierarchy using the following commands: Server: $ tcp_crr -6 Client: $ tcp_crr -6 -c -H ${server_ip} If the client and server run on different machines with 50 GBPS NIC, there is no visible impact of the change. For the same machine experiment with v6.11-rc5 as base. base (throughput) with-patch tcp_crr 14545 (+- 80) 14463 (+- 56) It seems like the performance impact is within the noise. Link: https://github.com/google/neper [1] Signed-off-by: Shakeel Butt <shakeel.butt@linux.dev> Reviewed-by: Roman Gushchin <roman.gushchin@linux.dev> Reviewed-by: Yosry Ahmed <yosryahmed@google.com> Acked-by: Paolo Abeni <pabeni@redhat.com> # net Signed-off-by: Vlastimil Babka <vbabka@suse.cz> |
||
Xavier
|
e02147cb70 |
mm/slab: Optimize the code logic in find_mergeable()
We can first assess the flags, if it's unmergeable, there's no need to calculate the size and align. Signed-off-by: Xavier <xavier_qy@163.com> Signed-off-by: Vlastimil Babka <vbabka@suse.cz> |
||
Linus Torvalds
|
4356ab331c |
vfs-6.11-rc7.fixes
-----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCZtQmqAAKCRCRxhvAZXjc os+mAP47NBhOecERCJSmS0RFMuRvc0ijxz1642emEthZhtf8qQD/cy56WmGZqEFZ bfj5v6tGmsxGt4xMDUDNG0pvqba8hwA= =JBA5 -----END PGP SIGNATURE----- Merge tag 'vfs-6.11-rc7.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull vfs fixes from Christian Brauner: "Two netfs fixes for this merge window: - Ensure that fscache_cookie_lru_time is deleted when the fscache module is removed to prevent UAF - Fix filemap_invalidate_inode() to use invalidate_inode_pages2_range() Before it used truncate_inode_pages_partial() which causes copy_file_range() to fail on cifs" * tag 'vfs-6.11-rc7.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: fscache: delete fscache_cookie_lru_timer when fscache exits to avoid UAF mm: Fix filemap_invalidate_inode() to use invalidate_inode_pages2_range() |
||
Linus Torvalds
|
76c0f27d06 |
17 hotfixes, 15 of which are cc:stable.
Mostly MM, no identifiable theme. And a few nilfs2 fixups. -----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQTTMBEPP41GrTpTJgfdBJ7gKXxAjgUCZtfR/wAKCRDdBJ7gKXxA jofjAP9rUlliIcn8zcy7vmBTuMaH4SkoULB64QWAUddaWV+SCAEA+q0sntLPnTIZ My3sfihR6mbvhkgKbvIHm6YYQI56NAc= =b4Lr -----END PGP SIGNATURE----- Merge tag 'mm-hotfixes-stable-2024-09-03-20-19' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull misc fixes from Andrew Morton: "17 hotfixes, 15 of which are cc:stable. Mostly MM, no identifiable theme. And a few nilfs2 fixups" * tag 'mm-hotfixes-stable-2024-09-03-20-19' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: alloc_tag: fix allocation tag reporting when CONFIG_MODULES=n mm: vmalloc: optimize vmap_lazy_nr arithmetic when purging each vmap_area mailmap: update entry for Jan Kuliga codetag: debug: mark codetags for poisoned page as empty mm/memcontrol: respect zswap.writeback setting from parent cg too scripts: fix gfp-translate after ___GFP_*_BITS conversion to an enum Revert "mm: skip CMA pages when they are not available" maple_tree: remove rcu_read_lock() from mt_validate() kexec_file: fix elfcorehdr digest exclusion when CONFIG_CRASH_HOTPLUG=y mm/slub: add check for s->flags in the alloc_tagging_slab_free_hook nilfs2: fix state management in error path of log writing function nilfs2: fix missing cleanup on rollforward recovery error nilfs2: protect references to superblock parameters exposed in sysfs userfaultfd: don't BUG_ON() if khugepaged yanks our page table userfaultfd: fix checks for huge PMDs mm: vmalloc: ensure vmap_block is initialised before adding to queue selftests: mm: fix build errors on armhf |
||
Peng Fan
|
59090e479a |
mm, slub: avoid zeroing kmalloc redzone
Since commit |
||
R Sundar
|
0f389adb4b |
mm: Removed @freeptr_offset to prevent doc warning
Removed @freeptr_offset to fix below doc warning. ./mm/slab_common.c:385: warning: Excess function parameter 'freeptr_offset' description in 'kmem_cache_create_usercopy' Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-kbuild-all/202408292249.5oUpnCbS-lkp@intel.com/ Signed-off-by: R Sundar <prosunofficial@gmail.com> Link: https://lore.kernel.org/r/20240902020555.11506-1-prosunofficial@gmail.com Signed-off-by: Christian Brauner <brauner@kernel.org> |
||
Adrian Huang
|
409faf8c97 |
mm: vmalloc: optimize vmap_lazy_nr arithmetic when purging each vmap_area
When running the vmalloc stress on a 448-core system, observe the average latency of purge_vmap_node() is about 2 seconds by using the eBPF/bcc 'funclatency.py' tool [1]. # /your-git-repo/bcc/tools/funclatency.py -u purge_vmap_node & pid1=$! && sleep 8 && modprobe test_vmalloc nr_threads=$(nproc) run_test_mask=0x7; kill -SIGINT $pid1 usecs : count distribution 0 -> 1 : 0 | | 2 -> 3 : 29 | | 4 -> 7 : 19 | | 8 -> 15 : 56 | | 16 -> 31 : 483 |**** | 32 -> 63 : 1548 |************ | 64 -> 127 : 2634 |********************* | 128 -> 255 : 2535 |********************* | 256 -> 511 : 1776 |************** | 512 -> 1023 : 1015 |******** | 1024 -> 2047 : 573 |**** | 2048 -> 4095 : 488 |**** | 4096 -> 8191 : 1091 |********* | 8192 -> 16383 : 3078 |************************* | 16384 -> 32767 : 4821 |****************************************| 32768 -> 65535 : 3318 |*************************** | 65536 -> 131071 : 1718 |************** | 131072 -> 262143 : 2220 |****************** | 262144 -> 524287 : 1147 |********* | 524288 -> 1048575 : 1179 |********* | 1048576 -> 2097151 : 822 |****** | 2097152 -> 4194303 : 906 |******* | 4194304 -> 8388607 : 2148 |***************** | 8388608 -> 16777215 : 4497 |************************************* | 16777216 -> 33554431 : 289 |** | avg = 2041714 usecs, total: 78381401772 usecs, count: 38390 The worst case is over 16-33 seconds, so soft lockup is triggered [2]. [Root Cause] 1) Each purge_list has the long list. The following shows the number of vmap_area is purged. crash> p vmap_nodes vmap_nodes = $27 = (struct vmap_node *) 0xff2de5a900100000 crash> vmap_node 0xff2de5a900100000 128 | grep nr_purged nr_purged = 663070 ... nr_purged = 821670 nr_purged = 692214 nr_purged = 726808 ... 2) atomic_long_sub() employs the 'lock' prefix to ensure the atomic operation when purging each vmap_area. However, the iteration is over 600000 vmap_area (See 'nr_purged' above). Here is objdump output: $ objdump -D vmlinux ffffffff813e8c80 <purge_vmap_node>: ... ffffffff813e8d70: f0 48 29 2d 68 0c bb lock sub %rbp,0x2bb0c68(%rip) ... Quote from "Instruction tables" pdf file [3]: Instructions with a LOCK prefix have a long latency that depends on cache organization and possibly RAM speed. If there are multiple processors or cores or direct memory access (DMA) devices, then all locked instructions will lock a cache line for exclusive access, which may involve RAM access. A LOCK prefix typically costs more than a hundred clock cycles, even on single-processor systems. That's why the latency of purge_vmap_node() dramatically increases on a many-core system: One core is busy on purging each vmap_area of the *long* purge_list and executing atomic_long_sub() for each vmap_area, while other cores free vmalloc allocations and execute atomic_long_add_return() in free_vmap_area_noflush(). [Solution] Employ a local variable to record the total purged pages, and execute atomic_long_sub() after the traversal of the purge_list is done. The experiment result shows the latency improvement is 99%. [Experiment Result] 1) System Configuration: Three servers (with HT-enabled) are tested. * 72-core server: 3rd Gen Intel Xeon Scalable Processor*1 * 192-core server: 5th Gen Intel Xeon Scalable Processor*2 * 448-core server: AMD Zen 4 Processor*2 2) Kernel Config * CONFIG_KASAN is disabled 3) The data in column "w/o patch" and "w/ patch" * Unit: micro seconds (us) * Each data is the average of 3-time measurements System w/o patch (us) w/ patch (us) Improvement (%) --------------- -------------- ------------- ------------- 72-core server 2194 14 99.36% 192-core server 143799 1139 99.21% 448-core server 1992122 6883 99.65% [1] https://github.com/iovisor/bcc/blob/master/tools/funclatency.py [2] https://gist.github.com/AdrianHuang/37c15f67b45407b83c2d32f918656c12 [3] https://www.agner.org/optimize/instruction_tables.pdf Link: https://lkml.kernel.org/r/20240829130633.2184-1-ahuang12@lenovo.com Signed-off-by: Adrian Huang <ahuang12@lenovo.com> Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
||
Hao Ge
|
5e9784e997 |
codetag: debug: mark codetags for poisoned page as empty
When PG_hwpoison pages are freed they are treated differently in
free_pages_prepare() and instead of being released they are isolated.
Page allocation tag counters are decremented at this point since the page
is considered not in use. Later on when such pages are released by
unpoison_memory(), the allocation tag counters will be decremented again
and the following warning gets reported:
[ 113.930443][ T3282] ------------[ cut here ]------------
[ 113.931105][ T3282] alloc_tag was not set
[ 113.931576][ T3282] WARNING: CPU: 2 PID: 3282 at ./include/linux/alloc_tag.h:130 pgalloc_tag_sub.part.66+0x154/0x164
[ 113.932866][ T3282] Modules linked in: hwpoison_inject fuse ip6t_rpfilter ip6t_REJECT nf_reject_ipv6 ipt_REJECT nf_reject_ipv4 xt_conntrack ebtable_nat ebtable_broute ip6table_nat ip6table_man4
[ 113.941638][ T3282] CPU: 2 UID: 0 PID: 3282 Comm: madvise11 Kdump: loaded Tainted: G W 6.11.0-rc4-dirty #18
[ 113.943003][ T3282] Tainted: [W]=WARN
[ 113.943453][ T3282] Hardware name: QEMU KVM Virtual Machine, BIOS unknown 2/2/2022
[ 113.944378][ T3282] pstate: 40400005 (nZcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[ 113.945319][ T3282] pc : pgalloc_tag_sub.part.66+0x154/0x164
[ 113.946016][ T3282] lr : pgalloc_tag_sub.part.66+0x154/0x164
[ 113.946706][ T3282] sp : ffff800087093a10
[ 113.947197][ T3282] x29: ffff800087093a10 x28: ffff0000d7a9d400 x27: ffff80008249f0a0
[ 113.948165][ T3282] x26: 0000000000000000 x25: ffff80008249f2b0 x24: 0000000000000000
[ 113.949134][ T3282] x23: 0000000000000001 x22: 0000000000000001 x21: 0000000000000000
[ 113.950597][ T3282] x20: ffff0000c08fcad8 x19: ffff80008251e000 x18: ffffffffffffffff
[ 113.952207][ T3282] x17: 0000000000000000 x16: 0000000000000000 x15: ffff800081746210
[ 113.953161][ T3282] x14: 0000000000000000 x13: 205d323832335420 x12: 5b5d353031313339
[ 113.954120][ T3282] x11: ffff800087093500 x10: 000000000000005d x9 : 00000000ffffffd0
[ 113.955078][ T3282] x8 : 7f7f7f7f7f7f7f7f x7 : ffff80008236ba90 x6 : c0000000ffff7fff
[ 113.956036][ T3282] x5 : ffff000b34bf4dc8 x4 : ffff8000820aba90 x3 : 0000000000000001
[ 113.956994][ T3282] x2 : ffff800ab320f000 x1 : 841d1e35ac932e00 x0 : 0000000000000000
[ 113.957962][ T3282] Call trace:
[ 113.958350][ T3282] pgalloc_tag_sub.part.66+0x154/0x164
[ 113.959000][ T3282] pgalloc_tag_sub+0x14/0x1c
[ 113.959539][ T3282] free_unref_page+0xf4/0x4b8
[ 113.960096][ T3282] __folio_put+0xd4/0x120
[ 113.960614][ T3282] folio_put+0x24/0x50
[ 113.961103][ T3282] unpoison_memory+0x4f0/0x5b0
[ 113.961678][ T3282] hwpoison_unpoison+0x30/0x48 [hwpoison_inject]
[ 113.962436][ T3282] simple_attr_write_xsigned.isra.34+0xec/0x1cc
[ 113.963183][ T3282] simple_attr_write+0x38/0x48
[ 113.963750][ T3282] debugfs_attr_write+0x54/0x80
[ 113.964330][ T3282] full_proxy_write+0x68/0x98
[ 113.964880][ T3282] vfs_write+0xdc/0x4d0
[ 113.965372][ T3282] ksys_write+0x78/0x100
[ 113.965875][ T3282] __arm64_sys_write+0x24/0x30
[ 113.966440][ T3282] invoke_syscall+0x7c/0x104
[ 113.966984][ T3282] el0_svc_common.constprop.1+0x88/0x104
[ 113.967652][ T3282] do_el0_svc+0x2c/0x38
[ 113.968893][ T3282] el0_svc+0x3c/0x1b8
[ 113.969379][ T3282] el0t_64_sync_handler+0x98/0xbc
[ 113.969980][ T3282] el0t_64_sync+0x19c/0x1a0
[ 113.970511][ T3282] ---[ end trace 0000000000000000 ]---
To fix this, clear the page tag reference after the page got isolated
and accounted for.
Link: https://lkml.kernel.org/r/20240825163649.33294-1-hao.ge@linux.dev
Fixes:
|
||
Mike Yuan
|
e399257349 |
mm/memcontrol: respect zswap.writeback setting from parent cg too
Currently, the behavior of zswap.writeback wrt. the cgroup hierarchy
seems a bit odd. Unlike zswap.max, it doesn't honor the value from parent
cgroups. This surfaced when people tried to globally disable zswap
writeback, i.e. reserve physical swap space only for hibernation [1] -
disabling zswap.writeback only for the root cgroup results in subcgroups
with zswap.writeback=1 still performing writeback.
The inconsistency became more noticeable after I introduced the
MemoryZSwapWriteback= systemd unit setting [2] for controlling the knob.
The patch assumed that the kernel would enforce the value of parent
cgroups. It could probably be workarounded from systemd's side, by going
up the slice unit tree and inheriting the value. Yet I think it's more
sensible to make it behave consistently with zswap.max and friends.
[1] https://wiki.archlinux.org/title/Power_management/Suspend_and_hibernate#Disable_zswap_writeback_to_use_the_swap_space_only_for_hibernation
[2] https://github.com/systemd/systemd/pull/31734
Link: https://lkml.kernel.org/r/20240823162506.12117-1-me@yhndnzj.com
Fixes:
|
||
Usama Arif
|
bfe0857c20 |
Revert "mm: skip CMA pages when they are not available"
This reverts commit |
||
Hao Ge
|
ab7ca09520 |
mm/slub: add check for s->flags in the alloc_tagging_slab_free_hook
When enable CONFIG_MEMCG & CONFIG_KFENCE & CONFIG_KMEMLEAK, the following
warning always occurs,This is because the following call stack occurred:
mem_pool_alloc
kmem_cache_alloc_noprof
slab_alloc_node
kfence_alloc
Once the kfence allocation is successful,slab->obj_exts will not be empty,
because it has already been assigned a value in kfence_init_pool.
Since in the prepare_slab_obj_exts_hook function,we perform a check for
s->flags & (SLAB_NO_OBJ_EXT | SLAB_NOLEAKTRACE),the alloc_tag_add function
will not be called as a result.Therefore,ref->ct remains NULL.
However,when we call mem_pool_free,since obj_ext is not empty, it
eventually leads to the alloc_tag_sub scenario being invoked. This is
where the warning occurs.
So we should add corresponding checks in the alloc_tagging_slab_free_hook.
For __GFP_NO_OBJ_EXT case,I didn't see the specific case where it's using
kfence,so I won't add the corresponding check in
alloc_tagging_slab_free_hook for now.
[ 3.734349] ------------[ cut here ]------------
[ 3.734807] alloc_tag was not set
[ 3.735129] WARNING: CPU: 4 PID: 40 at ./include/linux/alloc_tag.h:130 kmem_cache_free+0x444/0x574
[ 3.735866] Modules linked in: autofs4
[ 3.736211] CPU: 4 UID: 0 PID: 40 Comm: ksoftirqd/4 Tainted: G W 6.11.0-rc3-dirty #1
[ 3.736969] Tainted: [W]=WARN
[ 3.737258] Hardware name: QEMU KVM Virtual Machine, BIOS unknown 2/2/2022
[ 3.737875] pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[ 3.738501] pc : kmem_cache_free+0x444/0x574
[ 3.738951] lr : kmem_cache_free+0x444/0x574
[ 3.739361] sp : ffff80008357bb60
[ 3.739693] x29: ffff80008357bb70 x28: 0000000000000000 x27: 0000000000000000
[ 3.740338] x26: ffff80008207f000 x25: ffff000b2eb2fd60 x24: ffff0000c0005700
[ 3.740982] x23: ffff8000804229e4 x22: ffff800082080000 x21: ffff800081756000
[ 3.741630] x20: fffffd7ff8253360 x19: 00000000000000a8 x18: ffffffffffffffff
[ 3.742274] x17: ffff800ab327f000 x16: ffff800083398000 x15: ffff800081756df0
[ 3.742919] x14: 0000000000000000 x13: 205d344320202020 x12: 5b5d373038343337
[ 3.743560] x11: ffff80008357b650 x10: 000000000000005d x9 : 00000000ffffffd0
[ 3.744231] x8 : 7f7f7f7f7f7f7f7f x7 : ffff80008237bad0 x6 : c0000000ffff7fff
[ 3.744907] x5 : ffff80008237ba78 x4 : ffff8000820bbad0 x3 : 0000000000000001
[ 3.745580] x2 : 68d66547c09f7800 x1 : 68d66547c09f7800 x0 : 0000000000000000
[ 3.746255] Call trace:
[ 3.746530] kmem_cache_free+0x444/0x574
[ 3.746931] mem_pool_free+0x44/0xf4
[ 3.747306] free_object_rcu+0xc8/0xdc
[ 3.747693] rcu_do_batch+0x234/0x8a4
[ 3.748075] rcu_core+0x230/0x3e4
[ 3.748424] rcu_core_si+0x14/0x1c
[ 3.748780] handle_softirqs+0x134/0x378
[ 3.749189] run_ksoftirqd+0x70/0x9c
[ 3.749560] smpboot_thread_fn+0x148/0x22c
[ 3.749978] kthread+0x10c/0x118
[ 3.750323] ret_from_fork+0x10/0x20
[ 3.750696] ---[ end trace 0000000000000000 ]---
Link: https://lkml.kernel.org/r/20240816013336.17505-1-hao.ge@linux.dev
Fixes:
|
||
Jann Horn
|
4828d207dc |
userfaultfd: don't BUG_ON() if khugepaged yanks our page table
Since khugepaged was changed to allow retracting page tables in file
mappings without holding the mmap lock, these BUG_ON()s are wrong - get
rid of them.
We could also remove the preceding "if (unlikely(...))" block, but then we
could reach pte_offset_map_lock() with transhuge pages not just for file
mappings but also for anonymous mappings - which would probably be fine
but I think is not necessarily expected.
Link: https://lkml.kernel.org/r/20240813-uffd-thp-flip-fix-v2-2-5efa61078a41@google.com
Fixes:
|
||
Jann Horn
|
71c186efc1 |
userfaultfd: fix checks for huge PMDs
Patch series "userfaultfd: fix races around pmd_trans_huge() check", v2. The pmd_trans_huge() code in mfill_atomic() is wrong in three different ways depending on kernel version: 1. The pmd_trans_huge() check is racy and can lead to a BUG_ON() (if you hit the right two race windows) - I've tested this in a kernel build with some extra mdelay() calls. See the commit message for a description of the race scenario. On older kernels (before 6.5), I think the same bug can even theoretically lead to accessing transhuge page contents as a page table if you hit the right 5 narrow race windows (I haven't tested this case). 2. As pointed out by Qi Zheng, pmd_trans_huge() is not sufficient for detecting PMDs that don't point to page tables. On older kernels (before 6.5), you'd just have to win a single fairly wide race to hit this. I've tested this on 6.1 stable by racing migration (with a mdelay() patched into try_to_migrate()) against UFFDIO_ZEROPAGE - on my x86 VM, that causes a kernel oops in ptlock_ptr(). 3. On newer kernels (>=6.5), for shmem mappings, khugepaged is allowed to yank page tables out from under us (though I haven't tested that), so I think the BUG_ON() checks in mfill_atomic() are just wrong. I decided to write two separate fixes for these (one fix for bugs 1+2, one fix for bug 3), so that the first fix can be backported to kernels affected by bugs 1+2. This patch (of 2): This fixes two issues. I discovered that the following race can occur: mfill_atomic other thread ============ ============ <zap PMD> pmdp_get_lockless() [reads none pmd] <bail if trans_huge> <if none:> <pagefault creates transhuge zeropage> __pte_alloc [no-op] <zap PMD> <bail if pmd_trans_huge(*dst_pmd)> BUG_ON(pmd_none(*dst_pmd)) I have experimentally verified this in a kernel with extra mdelay() calls; the BUG_ON(pmd_none(*dst_pmd)) triggers. On kernels newer than commit |
||
Will Deacon
|
3e3de7947c |
mm: vmalloc: ensure vmap_block is initialised before adding to queue
Commit |
||
Linus Torvalds
|
c9f016e72b |
A set of X86 fixes:
- x2apic_disable() clears x2apic_state and x2apic_mode unconditionally, even when the state is X2APIC_ON_LOCKED, which prevents the kernel to disable it thereby creating inconsistent state. Reorder the logic so it actually works correctly - The XSTATE logic for handling LBR is incorrect as it assumes that XSAVES supports LBR when the CPU supports LBR. In fact both conditions need to be true. Otherwise the enablement of LBR in the IA32_XSS MSR fails and subsequently the machine crashes on the next XRSTORS operation because IA32_XSS is not initialized. Cache the XSTATE support bit during init and make the related functions use this cached information and the LBR CPU feature bit to cure this. - Cure a long standing bug in KASLR KASLR uses the full address space between PAGE_OFFSET and vaddr_end to randomize the starting points of the direct map, vmalloc and vmemmap regions. It thereby limits the size of the direct map by using the installed memory size plus an extra configurable margin for hot-plug memory. This limitation is done to gain more randomization space because otherwise only the holes between the direct map, vmalloc, vmemmap and vaddr_end would be usable for randomizing. The limited direct map size is not exposed to the rest of the kernel, so the memory hot-plug and resource management related code paths still operate under the assumption that the available address space can be determined with MAX_PHYSMEM_BITS. request_free_mem_region() allocates from (1 << MAX_PHYSMEM_BITS) - 1 downwards. That means the first allocation happens past the end of the direct map and if unlucky this address is in the vmalloc space, which causes high_memory to become greater than VMALLOC_START and consequently causes iounmap() to fail for valid ioremap addresses. Cure this by exposing the end of the direct map via PHYSMEM_END and use that for the memory hot-plug and resource management related places instead of relying on MAX_PHYSMEM_BITS. In the KASLR case PHYSMEM_END maps to a variable which is initialized by the KASLR initialization and otherwise it is based on MAX_PHYSMEM_BITS as before. - Prevent a data leak in mmio_read(). The TDVMCALL exposes the value of an initialized variabled on the stack to the VMM. The variable is only required as output value, so it does not have to exposed to the VMM in the first place. - Prevent an array overrun in the resource control code on systems with Sub-NUMA Clustering enabled because the code failed to adjust the index by the number of SNC nodes per L3 cache. -----BEGIN PGP SIGNATURE----- iQJHBAABCgAxFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAmbUUu0THHRnbHhAbGlu dXRyb25peC5kZQAKCRCmGPVMDXSYodFsEADFgxq2wjnH+VpuaIhLiQIfUa7iVeUl bwHAakZRMJ+Cb8BsvaRCMdAWWF+cRdLabAHuh7MRJFFzzdwrVTswnxT9baUBBjEe Kd3ZeQOS4AvWxpJNQEDg9r7tYtavmml9ix+Jh0OF+YmXLIweQk5RhDN+ncha07cJ 0DuPt4ngI24iyAyUX+7gZsRZiwoOm0HqImaRiisaspTbGpNwnrwFQCEioCdwnAv0 H5S7WTAlsZURCINLBNT+fV5oPjk2E3Ckj/CCJGoG1LYedGUD/44M1Hj0Xsqm4pHF Zd0+CuFyYpGqkAuBY6moWOheYP8V2U+yhf9Rtvh8/+h3qxZ/yon5i0ycO/2wMjiF 0NBomMeKh4PNyefYq8lHWK3kcXphrXH3yv09wVBDdLMXDy98beuS5NScGgza8148 /nqq0l1uLUyM9TkWg9H+4wW73EzQW1DYIliDU3tC98u+E77kQbyCx+2f0WI2k+ar 3wy7nYzyEJXl38NUTB+La4xXbhsELcaYQ/Q6scIsWAL+6+KlRb3FNBn+HT+KmOmF y702km/28C0uxrLk2OQCjX/zXQtXe2/4aoUzGqFf9atsifa0IBrc8YBzdIDB49Jt zz/MOAZTcz4jfyD3sRfYuG2QhBbdTz3f/kd3OryquitdAGozpoeztMIGs1PU2Y6s zInlLtUwaosadg== =T4i1 -----END PGP SIGNATURE----- Merge tag 'x86-urgent-2024-09-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Thomas Gleixner: - x2apic_disable() clears x2apic_state and x2apic_mode unconditionally, even when the state is X2APIC_ON_LOCKED, which prevents the kernel to disable it thereby creating inconsistent state. Reorder the logic so it actually works correctly - The XSTATE logic for handling LBR is incorrect as it assumes that XSAVES supports LBR when the CPU supports LBR. In fact both conditions need to be true. Otherwise the enablement of LBR in the IA32_XSS MSR fails and subsequently the machine crashes on the next XRSTORS operation because IA32_XSS is not initialized. Cache the XSTATE support bit during init and make the related functions use this cached information and the LBR CPU feature bit to cure this. - Cure a long standing bug in KASLR KASLR uses the full address space between PAGE_OFFSET and vaddr_end to randomize the starting points of the direct map, vmalloc and vmemmap regions. It thereby limits the size of the direct map by using the installed memory size plus an extra configurable margin for hot-plug memory. This limitation is done to gain more randomization space because otherwise only the holes between the direct map, vmalloc, vmemmap and vaddr_end would be usable for randomizing. The limited direct map size is not exposed to the rest of the kernel, so the memory hot-plug and resource management related code paths still operate under the assumption that the available address space can be determined with MAX_PHYSMEM_BITS. request_free_mem_region() allocates from (1 << MAX_PHYSMEM_BITS) - 1 downwards. That means the first allocation happens past the end of the direct map and if unlucky this address is in the vmalloc space, which causes high_memory to become greater than VMALLOC_START and consequently causes iounmap() to fail for valid ioremap addresses. Cure this by exposing the end of the direct map via PHYSMEM_END and use that for the memory hot-plug and resource management related places instead of relying on MAX_PHYSMEM_BITS. In the KASLR case PHYSMEM_END maps to a variable which is initialized by the KASLR initialization and otherwise it is based on MAX_PHYSMEM_BITS as before. - Prevent a data leak in mmio_read(). The TDVMCALL exposes the value of an initialized variabled on the stack to the VMM. The variable is only required as output value, so it does not have to exposed to the VMM in the first place. - Prevent an array overrun in the resource control code on systems with Sub-NUMA Clustering enabled because the code failed to adjust the index by the number of SNC nodes per L3 cache. * tag 'x86-urgent-2024-09-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/resctrl: Fix arch_mbm_* array overrun on SNC x86/tdx: Fix data leak in mmio_read() x86/kaslr: Expose and use the end of the physical memory address space x86/fpu: Avoid writing LBR bit to IA32_XSS unless supported x86/apic: Make x2apic_disable() work correctly |
||
David Howells
|
c26096ee02
|
mm: Fix filemap_invalidate_inode() to use invalidate_inode_pages2_range()
Fix filemap_invalidate_inode() to use invalidate_inode_pages2_range()
rather than truncate_inode_pages_range(). The latter clears the
invalidated bit of a partial pages rather than discarding it entirely.
This causes copy_file_range() to fail on cifs because the partial pages at
either end of the destination range aren't evicted and reread, but rather
just partly cleared.
This causes generic/075 and generic/112 xfstests to fail.
Fixes:
|
||
Christian Brauner
|
641bb4394f |
fs: move FMODE_UNSIGNED_OFFSET to fop_flags
This is another flag that is statically set and doesn't need to use up an FMODE_* bit. Move it to ->fop_flags and free up another FMODE_* bit. (1) mem_open() used from proc_mem_operations (2) adi_open() used from adi_fops (3) drm_open_helper(): (3.1) accel_open() used from DRM_ACCEL_FOPS (3.2) drm_open() used from (3.2.1) amdgpu_driver_kms_fops (3.2.2) psb_gem_fops (3.2.3) i915_driver_fops (3.2.4) nouveau_driver_fops (3.2.5) panthor_drm_driver_fops (3.2.6) radeon_driver_kms_fops (3.2.7) tegra_drm_fops (3.2.8) vmwgfx_driver_fops (3.2.9) xe_driver_fops (3.2.10) DRM_GEM_FOPS (3.2.11) DEFINE_DRM_GEM_DMA_FOPS (4) struct memdev sets fmode flags based on type of device opened. For devices using struct mem_fops unsigned offset is used. Mark all these file operations as FOP_UNSIGNED_OFFSET and add asserts into the open helper to ensure that the flag is always set. Link: https://lore.kernel.org/r/20240809-work-fop_unsigned-v1-1-658e054d893e@kernel.org Reviewed-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Christian Brauner <brauner@kernel.org> |
||
Christian Brauner
|
d345bd2e98 |
mm: add kmem_cache_create_rcu()
When a kmem cache is created with SLAB_TYPESAFE_BY_RCU the free pointer must be located outside of the object because we don't know what part of the memory can safely be overwritten as it may be needed to prevent object recycling. That has the consequence that SLAB_TYPESAFE_BY_RCU may end up adding a new cacheline. This is the case for e.g., struct file. After having it shrunk down by 40 bytes and having it fit in three cachelines we still have SLAB_TYPESAFE_BY_RCU adding a fourth cacheline because it needs to accommodate the free pointer. Add a new kmem_cache_create_rcu() function that allows the caller to specify an offset where the free pointer is supposed to be placed. Link: https://lore.kernel.org/r/20240828-work-kmem_cache-rcu-v3-2-5460bc1f09f6@kernel.org Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Christian Brauner <brauner@kernel.org> |
||
Christian Brauner
|
e446f18e98 |
mm: remove unused argument from create_cache()
That root_cache argument is unused so remove it. Link: https://lore.kernel.org/r/20240828-work-kmem_cache-rcu-v3-1-5460bc1f09f6@kernel.org Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Christian Brauner <brauner@kernel.org> |
||
Yan Zhen
|
3beb2fb681 |
mm, slab: use kmem_cache_free() to free from kmem_buckets_cache
In kmem_buckets_create(), the kmem_buckets object is allocated by kmem_cache_alloc() from kmem_buckets_cache, but in the failure case, it's freed by kfree(). This is not wrong, but using kmem_cache_free() is the more common pattern, so use it. Signed-off-by: Yan Zhen <yanzhen@vivo.com> Reviewed-by: Christoph Lameter <cl@linux.com> Signed-off-by: Vlastimil Babka <vbabka@suse.cz> |
||
Jann Horn
|
b8c8ba73c6 |
slub: Introduce CONFIG_SLUB_RCU_DEBUG
Currently, KASAN is unable to catch use-after-free in SLAB_TYPESAFE_BY_RCU slabs because use-after-free is allowed within the RCU grace period by design. Add a SLUB debugging feature which RCU-delays every individual kmem_cache_free() before either actually freeing the object or handing it off to KASAN, and change KASAN to poison freed objects as normal when this option is enabled. For now I've configured Kconfig.debug to default-enable this feature in the KASAN GENERIC and SW_TAGS modes; I'm not enabling it by default in HW_TAGS mode because I'm not sure if it might have unwanted performance degradation effects there. Note that this is mostly useful with KASAN in the quarantine-based GENERIC mode; SLAB_TYPESAFE_BY_RCU slabs are basically always also slabs with a ->ctor, and KASAN's assign_tag() currently has to assign fixed tags for those, reducing the effectiveness of SW_TAGS/HW_TAGS mode. (A possible future extension of this work would be to also let SLUB call the ->ctor() on every allocation instead of only when the slab page is allocated; then tag-based modes would be able to assign new tags on every reallocation.) Tested-by: syzbot+263726e59eab6b442723@syzkaller.appspotmail.com Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com> Acked-by: Marco Elver <elver@google.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> #slab Signed-off-by: Jann Horn <jannh@google.com> Signed-off-by: Vlastimil Babka <vbabka@suse.cz> |
||
Jann Horn
|
b3c3424575 |
kasan: catch invalid free before SLUB reinitializes the object
Currently, when KASAN is combined with init-on-free behavior, the initialization happens before KASAN's "invalid free" checks. More importantly, a subsequent commit will want to RCU-delay the actual SLUB freeing of an object, and we'd like KASAN to still validate synchronously that freeing the object is permitted. (Otherwise this change will make the existing testcase kmem_cache_invalid_free fail.) So add a new KASAN hook that allows KASAN to pre-validate a kmem_cache_free() operation before SLUB actually starts modifying the object or its metadata. Inside KASAN, this: - moves checks from poison_slab_object() into check_slab_allocation() - moves kasan_arch_is_ready() up into callers of poison_slab_object() - removes "ip" argument of poison_slab_object() and __kasan_slab_free() (since those functions no longer do any reporting) Acked-by: Vlastimil Babka <vbabka@suse.cz> #slub Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com> Signed-off-by: Jann Horn <jannh@google.com> Signed-off-by: Vlastimil Babka <vbabka@suse.cz> |
||
Vlastimil Babka
|
6c6c47b063 |
mm, slab: call kvfree_rcu_barrier() from kmem_cache_destroy()
We would like to replace call_rcu() users with kfree_rcu() where the
existing callback is just a kmem_cache_free(). However this causes
issues when the cache can be destroyed (such as due to module unload).
Currently such modules should be issuing rcu_barrier() before
kmem_cache_destroy() to have their call_rcu() callbacks processed first.
This barrier is however not sufficient for kfree_rcu() in flight due
to the batching introduced by
|
||
Vlastimil Babka
|
2eb14c1c27 |
mm, slab: reintroduce rcu_barrier() into kmem_cache_destroy()
There used to be a rcu_barrier() for SLAB_TYPESAFE_BY_RCU caches in kmem_cache_destroy() until commit |