kernel/linux.git/fs/ceph/inode.c, branch v7.2-rc2

ceph: add diagnostic timeout loop to wait_caps_flush()

2026-06-22T20:44:56+00:00

Convert wait_caps_flush() from a silent indefinite wait into a diagnostic wait loop that periodically dumps pending cap flush state. The underlying wait semantics remain intact: callers still wait until the requested cap flushes complete. The difference is that long stalls now produce actionable diagnostics instead of looking like a silent hang. CEPH_CAP_FLUSH_MAX_DUMP_ENTRIES limits the number of entries emitted per diagnostic dump, and CEPH_CAP_FLUSH_MAX_DUMP_ITERS limits the number of timed diagnostic dumps before the wait continues silently. When more entries exist than the per-dump limit, a truncation count is reported. When the dump iteration limit is reached, a final suppression message is emitted so the transition to silence is explicit. The diagnostic dump collects flush entry data under cap_dirty_lock into a bounded on-stack array, then prints after releasing the lock. This avoids holding the spinlock across printk calls. A null cf->ci on the global flush list indicates a bug since all cap_flush entries are initialized with a valid ci before being added. Signal this with WARN_ON_ONCE while still printing enough context for debugging. READ_ONCE is used for the i_last_cap_flush_ack field, which is read outside the inode lock domain. Flush tids are monotonically increasing and acks are processed in order under i_ceph_lock, so the latest ack tid is always the most recently written value. Add a ci pointer to struct ceph_cap_flush so that the diagnostic dump can identify which inode each pending flush belongs to. The new i_last_cap_flush_ack field tracks the latest acknowledged flush tid per inode for diagnostic correlation. This improves reset-drain observability and is also useful for existing sync and writeback troubleshooting paths. Signed-off-by: Alex Markuze Reviewed-by: Viacheslav Dubeyko Signed-off-by: Viacheslav Dubeyko Signed-off-by: Ilya Dryomov

ceph: convert inode flags to named bit positions and atomic bitops

2026-06-22T20:44:42+00:00

Define named bit-position constants for all CEPH_I_* inode flags and derive the bitmask values from them. This gives every flag a named _BIT constant usable with the test_bit/set_bit/clear_bit family. The intentionally unused bit position 1 is documented inline. Convert all flag modifications to use atomic bitops (set_bit, clear_bit, test_and_clear_bit). The previous code mixed lockless atomic ops on some flags (ERROR_WRITE, ODIRECT) with non-atomic read-modify-write (|= / &= ~) on other flags sharing the same unsigned long. A concurrent non-atomic RMW can clobber an adjacent lockless atomic update -- for example, a lockless clear_bit(ERROR_WRITE) could be silently resurrected by a concurrent ci->i_ceph_flags |= CEPH_I_FLUSH under the spinlock. Using atomic bitops for all modifications eliminates this class of race entirely. Flags whose only users are now the _BIT form (ERROR_WRITE, ASYNC_CHECK_CAPS) have their old mask defines removed to document that callers must use the _BIT constant with the set_bit/test_bit family. ERROR_FILELOCK and SHUTDOWN retain their mask defines because they are still used via bitmask tests in lockless readers (ceph_inode_is_shutdown, reconnect_caps_cb). The direct assignment in ceph_finish_async_create() is converted from i_ceph_flags = CEPH_I_ASYNC_CREATE to set_bit(). This inode is I_NEW at this point -- still invisible to other threads and guaranteed to have zero flags from alloc_inode -- so either form is safe, but set_bit() keeps the conversion uniform. Signed-off-by: Alex Markuze Reviewed-by: Viacheslav Dubeyko Signed-off-by: Viacheslav Dubeyko Signed-off-by: Ilya Dryomov

ceph: parse subvolume_id from InodeStat v9 and store in inode

2026-04-21T23:40:23+00:00

Add support for parsing the subvolume_id field from InodeStat v9 and storing it in the inode for later use by subvolume metrics tracking. The subvolume_id identifies which CephFS subvolume an inode belongs to, enabling per-subvolume I/O metrics collection and reporting. This patch: - Adds subvolume_id field to struct ceph_mds_reply_info_in - Adds i_subvolume_id field to struct ceph_inode_info - Parses subvolume_id from v9 InodeStat in parse_reply_info_in() - Adds ceph_inode_set_subvolume() helper to propagate the ID to inodes - Initializes i_subvolume_id in inode allocation and clears on destroy Signed-off-by: Alex Markuze Reviewed-by: Viacheslav Dubeyko Signed-off-by: Ilya Dryomov

ceph: add a bunch of missing ceph_path_info initializers

2026-03-09T11:34:40+00:00

ceph_mdsc_build_path() must be called with a zero-initialized ceph_path_info parameter, or else the following ceph_mdsc_free_path_info() may crash. Example crash (on Linux 6.18.12): virt_to_cache: Object is not a Slab page! WARNING: CPU: 184 PID: 2871736 at mm/slub.c:6732 kmem_cache_free+0x316/0x400 [...] Call Trace: [...] ceph_open+0x13d/0x3e0 do_dentry_open+0x134/0x480 vfs_open+0x2a/0xe0 path_openat+0x9a3/0x1160 [...] cache_from_obj: Wrong slab cache. names_cache but object is from ceph_inode_info WARNING: CPU: 184 PID: 2871736 at mm/slub.c:6746 kmem_cache_free+0x2dd/0x400 [...] kernel BUG at mm/slub.c:634! Oops: invalid opcode: 0000 [#1] SMP NOPTI RIP: 0010:__slab_free+0x1a4/0x350 Some of the ceph_mdsc_build_path() callers had initializers, but others had not, even though they were all added by commit 15f519e9f883 ("ceph: fix race condition validating r_parent before applying state"). The ones without initializer are suspectible to random crashes. (I can imagine it could even be possible to exploit this bug to elevate privileges.) Unfortunately, these Ceph functions are undocumented and its semantics can only be derived from the code. I see that ceph_mdsc_build_path() initializes the structure only on success, but not on error. Calling ceph_mdsc_free_path_info() after a failed ceph_mdsc_build_path() call does not even make sense, but that's what all callers do, and for it to be safe, the structure must be zero-initialized. The least intrusive approach to fix this is therefore to add initializers everywhere. Cc: stable@vger.kernel.org Fixes: 15f519e9f883 ("ceph: fix race condition validating r_parent before applying state") Signed-off-by: Max Kellermann Reviewed-by: Viacheslav Dubeyko Signed-off-by: Ilya Dryomov

treewide: Replace kmalloc with kmalloc_obj for non-scalar types

2026-02-21T09:02:28+00:00

This is the result of running the Coccinelle script from scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to avoid scalar types (which need careful case-by-case checking), and instead replace kmalloc-family calls that allocate struct or union object instances: Single allocations: kmalloc(sizeof(TYPE), ...) are replaced with: kmalloc_obj(TYPE, ...) Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...) are replaced with: kmalloc_objs(TYPE, COUNT, ...) Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...) are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...) (where TYPE may also be *VAR) The resulting allocations no longer return "void *", instead returning "TYPE *". Signed-off-by: Kees Cook

Merge tag 'mm-nonmm-stable-2025-12-06-11-14' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2025-12-06T22:01:20+00:00

Pull non-MM updates from Andrew Morton: - "panic: sys_info: Refactor and fix a potential issue" (Andy Shevchenko) fixes a build issue and does some cleanup in ib/sys_info.c - "Implement mul_u64_u64_div_u64_roundup()" (David Laight) enhances the 64-bit math code on behalf of a PWM driver and beefs up the test module for these library functions - "scripts/gdb/symbols: make BPF debug info available to GDB" (Ilya Leoshkevich) makes BPF symbol names, sizes, and line numbers available to the GDB debugger - "Enable hung_task and lockup cases to dump system info on demand" (Feng Tang) adds a sysctl which can be used to cause additional info dumping when the hung-task and lockup detectors fire - "lib/base64: add generic encoder/decoder, migrate users" (Kuan-Wei Chiu) adds a general base64 encoder/decoder to lib/ and migrates several users away from their private implementations - "rbree: inline rb_first() and rb_last()" (Eric Dumazet) makes TCP a little faster - "liveupdate: Rework KHO for in-kernel users" (Pasha Tatashin) reworks the KEXEC Handover interfaces in preparation for Live Update Orchestrator (LUO), and possibly for other future clients - "kho: simplify state machine and enable dynamic updates" (Pasha Tatashin) increases the flexibility of KEXEC Handover. Also preparation for LUO - "Live Update Orchestrator" (Pasha Tatashin) is a major new feature targeted at cloud environments. Quoting the cover letter: This series introduces the Live Update Orchestrator, a kernel subsystem designed to facilitate live kernel updates using a kexec-based reboot. This capability is critical for cloud environments, allowing hypervisors to be updated with minimal downtime for running virtual machines. LUO achieves this by preserving the state of selected resources, such as memory, devices and their dependencies, across the kernel transition. As a key feature, this series includes support for preserving memfd file descriptors, which allows critical in-memory data, such as guest RAM or any other large memory region, to be maintained in RAM across the kexec reboot. Mike Rappaport merits a mention here, for his extensive review and testing work. - "kexec: reorganize kexec and kdump sysfs" (Sourabh Jain) moves the kexec and kdump sysfs entries from /sys/kernel/ to /sys/kernel/kexec/ and adds back-compatibility symlinks which can hopefully be removed one day - "kho: fixes for vmalloc restoration" (Mike Rapoport) fixes a BUG which was being hit during KHO restoration of vmalloc() regions * tag 'mm-nonmm-stable-2025-12-06-11-14' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (139 commits) calibrate: update header inclusion Reinstate "resource: avoid unnecessary lookups in find_next_iomem_res()" vmcoreinfo: track and log recoverable hardware errors kho: fix restoring of contiguous ranges of order-0 pages kho: kho_restore_vmalloc: fix initialization of pages array MAINTAINERS: TPM DEVICE DRIVER: update the W-tag init: replace simple_strtoul with kstrtoul to improve lpj_setup KHO: fix boot failure due to kmemleak access to non-PRESENT pages Documentation/ABI: new kexec and kdump sysfs interface Documentation/ABI: mark old kexec sysfs deprecated kexec: move sysfs entries to /sys/kernel/kexec test_kho: always print restore status kho: free chunks using free_page() instead of kfree() selftests/liveupdate: add kexec test for multiple and empty sessions selftests/liveupdate: add simple kexec-based selftest for LUO selftests/liveupdate: add userspace API selftests docs: add documentation for memfd preservation via LUO mm: memfd_luo: allow preserving memfd liveupdate: luo_file: add private argument to store runtime state mm: shmem: export some functions to internal.h ...

Merge tag 'printk-for-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux

2025-12-03T20:42:36+00:00

Pull printk updates from Petr Mladek: - Allow creaing nbcon console drivers with an unsafe write_atomic() callback that can only be called by the final nbcon_atomic_flush_unsafe(). Otherwise, the driver would rely on the kthread. It is going to be used as the-best-effort approach for an experimental nbcon netconsole driver, see https://lore.kernel.org/r/20251121-nbcon-v1-2-503d17b2b4af@debian.org Note that a safe .write_atomic() callback is supposed to work in NMI context. But some networking drivers are not safe even in IRQ context: https://lore.kernel.org/r/oc46gdpmmlly5o44obvmoatfqo5bhpgv7pabpvb6sjuqioymcg@gjsma3ghoz35 In an ideal world, all networking drivers would be fixed first and the atomic flush would be blocked only in NMI context. But it brings the question how reliable networking drivers are when the system is in a bad state. They might block flushing more reliable serial consoles which are more suitable for serious debugging anyway. - Allow to use the last 4 bytes of the printk ring buffer. - Prevent queuing IRQ work and block printk kthreads when consoles are suspended. Otherwise, they create non-necessary churn or even block the suspend. - Release console_lock() between each record in the kthread used for legacy consoles on RT. It might significantly speed up the boot. - Release nbcon context between each record in the atomic flush. It prevents stalls of the related printk kthread after it has lost the ownership in the middle of a record - Add support for NBCON consoles into KDB - Add %ptsP modifier for printing struct timespec64 and use it where possible - Misc code clean up * tag 'printk-for-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux: (48 commits) printk: Use console_is_usable on console_unblank arch: um: kmsg_dump: Use console_is_usable drivers: serial: kgdboc: Drop checks for CON_ENABLED and CON_BOOT lib/vsprintf: Unify FORMAT_STATE_NUM handlers printk: Avoid irq_work for printk_deferred() on suspend printk: Avoid scheduling irq_work on suspend printk: Allow printk_trigger_flush() to flush all types tracing: Switch to use %ptSp scsi: snic: Switch to use %ptSp scsi: fnic: Switch to use %ptSp s390/dasd: Switch to use %ptSp ptp: ocp: Switch to use %ptSp pps: Switch to use %ptSp PCI: epf-test: Switch to use %ptSp net: dsa: sja1105: Switch to use %ptSp mmc: mmc_test: Switch to use %ptSp media: av7110: Switch to use %ptSp ipmi: Switch to use %ptSp igb: Switch to use %ptSp e1000e: Switch to use %ptSp ...

ceph: replace local base64 helpers with lib/base64

2025-11-20T22:03:44+00:00

Remove the ceph_base64_encode() and ceph_base64_decode() functions and replace their usage with the generic base64_encode() and base64_decode() helpers from lib/base64. This eliminates the custom implementation in Ceph, reduces code duplication, and relies on the shared Base64 code in lib. The helpers preserve RFC 3501-compliant Base64 encoding without padding, so there are no functional changes. This change also improves performance: encoding is about 2.7x faster and decoding achieves 43-52x speedups compared to the previous local implementation. Link: https://lkml.kernel.org/r/20251114060240.89965-1-409411716@gms.tku.edu.tw Signed-off-by: Guan-Chun Wu <409411716@gms.tku.edu.tw> Reviewed-by: Kuan-Wei Chiu Reviewed-by: Viacheslav Dubeyko Cc: Keith Busch Cc: Jens Axboe Cc: Christoph Hellwig Cc: Sagi Grimberg Cc: Xiubo Li Cc: Ilya Dryomov Cc: Eric Biggers Cc: "Theodore Y. Ts'o" Cc: Jaegeuk Kim Cc: David Laight Cc: Yu-Sheng Huang Signed-off-by: Andrew Morton

ceph: Switch to use %ptSp

2025-11-19T09:24:13+00:00

Use %ptSp instead of open coded variants to print content of struct timespec64 in human readable format. Reviewed-by: Viacheslav Dubeyko Signed-off-by: Andy Shevchenko Link: https://patch.msgid.link/20251113150217.3030010-3-andriy.shevchenko@linux.intel.com Signed-off-by: Petr Mladek

ceph: use the new ->i_state accessors

2025-10-20T18:22:27+00:00

Change generated with coccinelle and fixed up by hand as appropriate. Signed-off-by: Mateusz Guzik Signed-off-by: Christian Brauner