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2025-03-05inet: fix lwtunnel_valid_encap_type() lock imbalanceEric Dumazet
After blamed commit rtm_to_fib_config() now calls lwtunnel_valid_encap_type{_attr}() without RTNL held, triggering an unlock balance in __rtnl_unlock, as reported by syzbot [1] IPv6 and rtm_to_nh_config() are not yet converted. Add a temporary @rtnl_is_held parameter to lwtunnel_valid_encap_type() and lwtunnel_valid_encap_type_attr(). While we are at it replace the two rcu_dereference() in lwtunnel_valid_encap_type() with more appropriate rcu_access_pointer(). [1] syz-executor245/5836 is trying to release lock (rtnl_mutex) at: [<ffffffff89d0e38c>] __rtnl_unlock+0x6c/0xf0 net/core/rtnetlink.c:142 but there are no more locks to release! other info that might help us debug this: no locks held by syz-executor245/5836. stack backtrace: CPU: 0 UID: 0 PID: 5836 Comm: syz-executor245 Not tainted 6.14.0-rc4-syzkaller-00873-g3424291dd242 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: <TASK> __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_unlock_imbalance_bug+0x25b/0x2d0 kernel/locking/lockdep.c:5289 __lock_release kernel/locking/lockdep.c:5518 [inline] lock_release+0x47e/0xa30 kernel/locking/lockdep.c:5872 __mutex_unlock_slowpath+0xec/0x800 kernel/locking/mutex.c:891 __rtnl_unlock+0x6c/0xf0 net/core/rtnetlink.c:142 lwtunnel_valid_encap_type+0x38a/0x5f0 net/core/lwtunnel.c:169 lwtunnel_valid_encap_type_attr+0x113/0x270 net/core/lwtunnel.c:209 rtm_to_fib_config+0x949/0x14e0 net/ipv4/fib_frontend.c:808 inet_rtm_newroute+0xf6/0x2a0 net/ipv4/fib_frontend.c:917 rtnetlink_rcv_msg+0x791/0xcf0 net/core/rtnetlink.c:6919 netlink_rcv_skb+0x206/0x480 net/netlink/af_netlink.c:2534 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline] netlink_unicast+0x7f6/0x990 net/netlink/af_netlink.c:1339 netlink_sendmsg+0x8de/0xcb0 net/netlink/af_netlink.c:1883 sock_sendmsg_nosec net/socket.c:709 [inline] Fixes: 1dd2af7963e9 ("ipv4: fib: Convert RTM_NEWROUTE and RTM_DELROUTE to per-netns RTNL.") Reported-by: syzbot+3f18ef0f7df107a3f6a0@syzkaller.appspotmail.com Closes: https://lore.kernel.org/netdev/67c6f87a.050a0220.38b91b.0147.GAE@google.com/T/#u Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Link: https://patch.msgid.link/20250304125918.2763514-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-03-05net: phy: remove remaining PHY package related definitions from phy.hHeiner Kallweit
Move definition of struct phy_package_shared to phy_package.c, and move remaining PHY package related declarations from phy.h to phylib.h, thus making them accessible for PHY drivers only. Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> Link: https://patch.msgid.link/211e14b6-e2f8-43d7-b533-3628ec548456@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-03-05net: phy: move PHY package related code from phy.h to phy_package.cHeiner Kallweit
Move PHY package related inline functions from phy.h to phy_package.c. While doing so remove locked versions phy_package_read() and phy_package_write() which have no user. Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> Link: https://patch.msgid.link/a4518379-7a5d-45f3-831c-b7fde6512c65@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-03-05net: stmmac: configure SerDes on mac_finishChoong Yong Liang
SerDes will configure according to the provided interface mode after finish a major reconfiguration of the interface mode. Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Signed-off-by: Choong Yong Liang <yong.liang.choong@linux.intel.com> Link: https://patch.msgid.link/20250227121522.1802832-5-yong.liang.choong@linux.intel.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-03-05arch: x86: add IPC mailbox accessor function and add SoC register accessDavid E. Box
- Exports intel_pmc_ipc() for host access to the PMC IPC mailbox - Enables the host to access specific SoC registers through the PMC firmware using IPC commands. This access method is necessary for registers that are not available through direct Memory-Mapped I/O (MMIO), which is used for other accessible parts of the PMC. Signed-off-by: David E. Box <david.e.box@linux.intel.com> Signed-off-by: Chao Qin <chao.qin@intel.com> Signed-off-by: Choong Yong Liang <yong.liang.choong@linux.intel.com> Acked-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://patch.msgid.link/20250227121522.1802832-4-yong.liang.choong@linux.intel.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-03-05drm/fb-helper: Remove struct drm_fb_helper.fb_probeThomas Zimmermann
The callback fb_probe in struct drm_fb_helper is unused. Remove it. New drivers should set struct drm_driver.fbdev_probe instead and call drm_client_setup() to instantiate in-kernel DRM clients. Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20241212170913.185939-13-tzimmermann@suse.de Signed-off-by: Maarten Lankhorst <dev@lankhorst.se>
2025-03-05drm/i915/display: fbdev: Move custom suspend code to new callbackThomas Zimmermann
If the fbdev buffer is backed by stolen memory, it has to be cleared upon resume from hibernation. Move the code into the new callback fb_set_suspend, so that it can run from DRM's generic fbdev client. No functional change. Other drivers are not affected. Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20241212170913.185939-7-tzimmermann@suse.de Signed-off-by: Maarten Lankhorst <dev@lankhorst.se>
2025-03-05drm/i915/display: fbdev: Move custom restore code to new callbackThomas Zimmermann
i915's fbdev contains code for restoring the client's framebuffer. It is specific to i195 and cannot be ported to the common fbdev client. Introduce the callback struct drm_fb_helper.fb_restore and implement it for i915. The fbdev helpers invoke the callback after restoring the fbdev client. Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20241212170913.185939-6-tzimmermann@suse.de Signed-off-by: Maarten Lankhorst <dev@lankhorst.se>
2025-03-05drm/client: Send pending hotplug events after resumeThomas Zimmermann
If a hotplug event arrives while the client has been suspended, DRM's client code will deliver the event after resuming. The functionality has been taken form i915, where it can be removed by a later commit. Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20241212170913.185939-4-tzimmermann@suse.de Signed-off-by: Maarten Lankhorst <dev@lankhorst.se>
2025-03-05ASoC: Merge up fixesMark Brown
Merge branch 'for-6.14' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into asoc-6.15 to avoid a bunch of add/add conflicts.
2025-03-05fs/pipe: remove buggy and unused 'helper' functionLinus Torvalds
While looking for incorrect users of the pipe head/tail fields (see commit c27c66afc449: "fs/pipe: Fix pipe_occupancy() with 16-bit indexes"), I found a bug in pipe_discard_from() that looked entirely broken. However, the fix is trivial: this buggy function isn't actually called by anything, so let's just remove it ASAP. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2025-03-05file: add fput and file_ref_put routines optimized for use when closing a fdMateusz Guzik
Vast majority of the time closing a file descriptor also operates on the last reference, where a regular fput usage will result in 2 atomics. This can be changed to only suffer 1. See commentary above file_ref_put_close() for more information. Signed-off-by: Mateusz Guzik <mjguzik@gmail.com> Link: https://lore.kernel.org/r/20250305123644.554845-2-mjguzik@gmail.com Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-03-05ASoC: ops: Consistently treat platform_max as control valueCharles Keepax
This reverts commit 9bdd10d57a88 ("ASoC: ops: Shift tested values in snd_soc_put_volsw() by +min"), and makes some additional related updates. There are two ways the platform_max could be interpreted; the maximum register value, or the maximum value the control can be set to. The patch moved from treating the value as a control value to a register one. When the patch was applied it was technically correct as snd_soc_limit_volume() also used the register interpretation. However, even then most of the other usages treated platform_max as a control value, and snd_soc_limit_volume() has since been updated to also do so in commit fb9ad24485087 ("ASoC: ops: add correct range check for limiting volume"). That patch however, missed updating snd_soc_put_volsw() back to the control interpretation, and fixing snd_soc_info_volsw_range(). The control interpretation makes more sense as limiting is typically done from the machine driver, so it is appropriate to use the customer facing representation rather than the internal codec representation. Update all the code to consistently use this interpretation of platform_max. Finally, also add some comments to the soc_mixer_control struct to hopefully avoid further patches switching between the two approaches. Fixes: fb9ad24485087 ("ASoC: ops: add correct range check for limiting volume") Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com> Link: https://patch.msgid.link/20250228151456.3703342-1-ckeepax@opensource.cirrus.com Signed-off-by: Mark Brown <broonie@kernel.org>
2025-03-05include/linux/pipe_fs_i: Add htmldoc annotation for "head_tail" memberK Prateek Nayak
Add htmldoc annotation for the newly introduced "head_tail" member describing it to be a union of the pipe_inode_info's @head and @tail members. Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Closes: https://lore.kernel.org/lkml/20250305204609.5e64768e@canb.auug.org.au/ Fixes: 3d252160b818 ("fs/pipe: Read pipe->{head,tail} atomically outside pipe->mutex") Signed-off-by: K Prateek Nayak <kprateek.nayak@amd.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2025-03-05fs/pipe: Fix pipe_occupancy() with 16-bit indexesLinus Torvalds
The pipe_occupancy() logic implicitly relied on the natural unsigned modulo arithmetic in C, but that doesn't work for the new 'pipe_index_t' case, since any arithmetic will be done in 'int' (and here we had also made it 'unsigned int' due to the function call boundary). So make the modulo arithmetic explicit by casting the result to the proper type. Cc: Oleg Nesterov <oleg@redhat.com> Cc: Mateusz Guzik <mjguzik@gmail.com> Cc: Manfred Spraul <manfred@colorfullife.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Swapnil Sapkal <swapnil.sapkal@amd.com> Cc: Alexey Gladkov <legion@kernel.org> Cc: K Prateek Nayak <kprateek.nayak@amd.com> Link: https://lore.kernel.org/all/CAHk-=wjyHsGLx=rxg6PKYBNkPYAejgo7=CbyL3=HGLZLsAaJFQ@mail.gmail.com/ Fixes: 3d252160b818 ("fs/pipe: Read pipe->{head,tail} atomically outside pipe->mutex") Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2025-03-05treewide: fix typo 'unsigned __init128' -> 'unsigned __int128'Vincent Mailhol
"int" was misspelled as "init" the code comments in the bits.h and const.h files. Fix the typo. CC: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Signed-off-by: Yury Norov <yury.norov@gmail.com>
2025-03-05drm/ttm: Add helpers for shrinkingThomas Hellström
Add a number of helpers for shrinking that access core TTM and core MM functionality in a way that make them unsuitable for driver open-coding. v11: - New patch (split off from previous) and additional helpers. v13: - Adapt to ttm_backup interface change. - Take resource off LRU when backed up. Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> Reviewed-by: Matthew Brost <matthew.brost@intel.com> Acked-by: Dave Airlie <airlied@redhat.com> Acked-by: Christian König <christian.koenig@amd.com> Link: https://lore.kernel.org/intel-xe/20250305092220.123405-6-thomas.hellstrom@linux.intel.com
2025-03-05drm/ttm: Add a macro to perform LRU iterationThomas Hellström
Following the design direction communicated here: https://lore.kernel.org/linux-mm/b7491378-defd-4f1c-31e2-29e4c77e2d67@amd.com/T/#ma918844aa8a6efe8768fdcda0c6590d5c93850c9 Export a LRU walker for driver shrinker use. The walker initially supports only trylocking, since that's the method used by shrinkes. The walker makes use of scoped_guard() to allow exiting from the LRU walk loop without performing any explicit unlocking or cleanup. v8: - Split out from another patch. - Use a struct for bool arguments to increase readability (Matt Brost). - Unmap user-space cpu-mappings before shrinking pages. - Explain non-fatal error codes (Matt Brost) v10: - Instead of using the existing helper, Wrap the interface inside out and provide a loop to de-midlayer things the LRU iteration (Christian König). - Removing the R-B by Matt Brost since the patch was significantly changed. v11: - Split the patch up to include just the LRU walk helper. v12: - Indent after scoped_guard() (Matt Brost) v15: - Adapt to new definition of scoped_guard() Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> Reviewed-by: Matthew Brost <matthew.brost@intel.com> Acked-by: Dave Airlie <airlied@redhat.com> Acked-by: Christian König <christian.koenig@amd.com> Link: https://lore.kernel.org/intel-xe/20250305092220.123405-5-thomas.hellstrom@linux.intel.com
2025-03-05drm/ttm/pool, drm/ttm/tt: Provide a helper to shrink pagesThomas Hellström
Provide a helper to shrink ttm_tt page-vectors on a per-page basis. A ttm_backup backend could then in theory get away with allocating a single temporary page for each struct ttm_tt. This is accomplished by splitting larger pages before trying to back them up. In the future we could allow ttm_backup to handle backing up large pages as well, but currently there's no benefit in doing that, since the shmem backup backend would have to split those anyway to avoid allocating too much temporary memory, and if the backend instead inserts pages into the swap-cache, those are split on reclaim by the core. Due to potential backup- and recover errors, allow partially swapped out struct ttm_tt's, although mark them as swapped out stopping them from being swapped out a second time. More details in the ttm_pool.c DOC section. v2: - A couple of cleanups and error fixes in ttm_pool_back_up_tt. - s/back_up/backup/ - Add a writeback parameter to the exported interface. v8: - Use a struct for flags for readability (Matt Brost) - Address misc other review comments (Matt Brost) v9: - Update the kerneldoc for the ttm_tt::backup field. v10: - Rebase. v13: - Rebase on ttm_backup interface change. Update kerneldoc. - Rebase and adjust ttm_tt_is_swapped(). v15: - Rebase on ttm_backup return value change. - Rebase on previous restructuring of ttm_pool_alloc() - Rework the ttm_pool backup interface (Christian König) - Remove cond_resched() (Christian König) - Get rid of the need to allocate an intermediate page array when restoring a multi-order page (Christian König) - Update documentation. Cc: Christian König <christian.koenig@amd.com> Cc: Somalapuram Amaranath <Amaranath.Somalapuram@amd.com> Cc: Matthew Brost <matthew.brost@intel.com> Cc: <dri-devel@lists.freedesktop.org> Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> Reviewed-by: Matthew Brost <matthew.brost@intel.com> Acked-by: Christian Koenig <christian.koenig@amd.com> Link: https://lore.kernel.org/intel-xe/20250305092220.123405-3-thomas.hellstrom@linux.intel.com
2025-03-05drm/ttm: Provide a shmem backup implementationThomas Hellström
Provide a standalone shmem backup implementation. Given the ttm_backup interface, this could later on be extended to providing other backup implementation than shmem, with one use-case being GPU swapout to a user-provided fd. v5: - Fix a UAF. (kernel test robot, Dan Carptenter) v6: - Rename ttm_backup_shmem_copy_page() function argument (Matthew Brost) - Add some missing documentation v8: - Use folio_file_page to get to the page we want to writeback instead of using the first page of the folio. v13: - Remove the base class abstraction (Christian König) - Include ttm_backup_bytes_avail(). v14: - Fix kerneldoc for ttm_backup_bytes_avail() (0-day) - Work around casting of __randomize_layout struct pointer (0-day) v15: - Return negative error code from ttm_backup_backup_page() (Christian König) - Doc fixes. (Christian König). Cc: Christian König <christian.koenig@amd.com> Cc: Somalapuram Amaranath <Amaranath.Somalapuram@amd.com> Cc: Matthew Brost <matthew.brost@intel.com> Cc: <dri-devel@lists.freedesktop.org> Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> Reviewed-by: Matthew Brost <matthew.brost@intel.com> Reviewed-by: Christian König <christian.koenig@amd.com> Link: https://lore.kernel.org/intel-xe/20250305092220.123405-2-thomas.hellstrom@linux.intel.com
2025-03-05drm/amdkfd: flag per-sdma queue reset supported to user spaceJonathan Kim
Similar to compute queue reset, flag SDMA queue reset capabilities to user space for safe testing. Signed-off-by: Jonathan Kim <jonathan.kim@amd.com> Reviewed-by: Harish Kasiviswanathan <harish.kasiviswanathan@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2025-03-05gpio: Hide valid_mask from direct assignmentsMatti Vaittinen
The valid_mask member of the struct gpio_chip is unconditionally written by the GPIO core at driver registration. Current documentation does not mention this but just says the valid_mask is used if it's not NULL. This lured me to try populating it directly in the GPIO driver probe instead of using the init_valid_mask() callback. It took some retries with different bitmaps and eventually a bit of code-reading to understand why the valid_mask was not obeyed. I could've avoided this trial and error if the valid_mask was hidden in the struct gpio_device instead of being a visible member of the struct gpio_chip. Help the next developer who decides to directly populate the valid_mask in struct gpio_chip by hiding the valid_mask in struct gpio_device and keep it internal to the GPIO core. Suggested-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Matti Vaittinen <mazziesaccount@gmail.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/4547ca90d910d60cab3d56d864d59ddde47a5e93.1741180097.git.mazziesaccount@gmail.com Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2025-03-05gpio: Add a valid_mask getterMatti Vaittinen
The valid_mask member of the struct gpio_chip is unconditionally written by the GPIO core at driver registration. It shouldn't be directly populated by drivers. This can be prevented by moving it from the struct gpio_chip to struct gpio_device, which is internal to the GPIO core. As a preparatory step, provide a getter function which can be used by those drivers which need the valid_mask information. Signed-off-by: Matti Vaittinen <mazziesaccount@gmail.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/026f9d78502eca883bfe3faeb684e23d5d6c5e84.1741180097.git.mazziesaccount@gmail.com Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2025-03-05posix-clock: Store file pointer in struct posix_clock_contextWojtek Wasko
File descriptor based pc_clock_*() operations of dynamic posix clocks have access to the file pointer and implement permission checks in the generic code before invoking the relevant dynamic clock callback. Character device operations (open, read, poll, ioctl) do not implement a generic permission control and the dynamic clock callbacks have no access to the file pointer to implement them. Extend struct posix_clock_context with a struct file pointer and initialize it in posix_clock_open(), so that all dynamic clock callbacks can access it. Acked-by: Richard Cochran <richardcochran@gmail.com> Reviewed-by: Vadim Fedorenko <vadim.fedorenko@linux.dev> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Wojtek Wasko <wwasko@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2025-03-05pidfs: allow to retrieve exit informationChristian Brauner
Some tools like systemd's jounral need to retrieve the exit and cgroup information after a process has already been reaped. This can e.g., happen when retrieving a pidfd via SCM_PIDFD or SCM_PEERPIDFD. Link: https://lore.kernel.org/r/20250305-work-pidfs-kill_on_last_close-v3-6-c8c3d8361705@kernel.org Reviewed-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-03-05pidfs: record exit code and cgroupid at exitChristian Brauner
Record the exit code and cgroupid in release_task() and stash in struct pidfs_exit_info so it can be retrieved even after the task has been reaped. Link: https://lore.kernel.org/r/20250305-work-pidfs-kill_on_last_close-v3-5-c8c3d8361705@kernel.org Reviewed-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-03-05fscrypt: Change fscrypt_encrypt_pagecache_blocks() to take a folioMatthew Wilcox (Oracle)
ext4 and ceph already have a folio to pass; f2fs needs to be properly converted but this will do for now. This removes a reference to page->index and page->mapping as well as removing a call to compound_head(). Signed-off-by: "Matthew Wilcox (Oracle)" <willy@infradead.org> Link: https://lore.kernel.org/r/20250304170224.523141-1-willy@infradead.org Acked-by: Eric Biggers <ebiggers@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-03-05VFS: Change vfs_mkdir() to return the dentry.NeilBrown
vfs_mkdir() does not guarantee to leave the child dentry hashed or make it positive on success, and in many such cases the filesystem had to use a different dentry which it can now return. This patch changes vfs_mkdir() to return the dentry provided by the filesystems which is hashed and positive when provided. This reduces the number of cases where the resulting dentry is not positive to a handful which don't deserve extra efforts. The only callers of vfs_mkdir() which are interested in the resulting inode are in-kernel filesystem clients: cachefiles, nfsd, smb/server. The only filesystems that don't reliably provide the inode are: - kernfs, tracefs which these clients are unlikely to be interested in - cifs in some configurations would need to do a lookup to find the created inode, but doesn't. cifs cannot be exported via NFS, is unlikely to be used by cachefiles, and smb/server only has a soft requirement for the inode, so this is unlikely to be a problem in practice. - hostfs, nfs, cifs may need to do a lookup (rarely for NFS) and it is possible for a race to make that lookup fail. Actual failure is unlikely and providing callers handle negative dentries graceful they will fail-safe. So this patch removes the lookup code in nfsd and smb/server and adjusts them to fail safe if a negative dentry is provided: - cache-files already fails safe by restarting the task from the top - it still does with this change, though it no longer calls cachefiles_put_directory() as that will crash if the dentry is negative. - nfsd reports "Server-fault" which it what it used to do if the lookup failed. This will never happen on any file-systems that it can actually export, so this is of no consequence. I removed the fh_update() call as that is not needed and out-of-place. A subsequent nfsd_create_setattr() call will call fh_update() when needed. - smb/server only wants the inode to call ksmbd_smb_inherit_owner() which updates ->i_uid (without calling notify_change() or similar) which can be safely skipping on cifs (I hope). If a different dentry is returned, the first one is put. If necessary the fact that it is new can be determined by comparing pointers. A new dentry will certainly have a new pointer (as the old is put after the new is obtained). Similarly if an error is returned (via ERR_PTR()) the original dentry is put. Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: NeilBrown <neilb@suse.de> Link: https://lore.kernel.org/r/20250227013949.536172-7-neilb@suse.de Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-03-05nfs: change mkdir inode_operation to return alternate dentry if needed.NeilBrown
mkdir now allows a different dentry to be returned which is sometimes relevant for nfs. This patch changes the nfs_rpc_ops mkdir op to return a dentry, and passes that back to the caller. The mkdir nfs_rpc_op will return NULL if the original dentry should be used. This matches the mkdir inode_operation. nfs4_do_create() is duplicated to nfs4_do_mkdir() which is changed to handle the specifics of directories. Consequently the current special handling for directories is removed from nfs4_do_create() Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: NeilBrown <neilb@suse.de> Link: https://lore.kernel.org/r/20250227013949.536172-6-neilb@suse.de Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-03-05media: v4l2-core: Introduce v4l2_query_ext_ctrl_to_v4l2_queryctrlRicardo Ribalda
We use this logic in a couple of places. Refactor into a function. No functional change expected from this patch. Signed-off-by: Ricardo Ribalda <ribalda@chromium.org> Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2025-03-05media: v4l2: Remove vidioc_s_ctrl callbackRicardo Ribalda
All the drivers either use the control framework or provide a vidiod_ext_ctrl. We can remove this callback. Signed-off-by: Ricardo Ribalda <ribalda@chromium.org> Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2025-03-05media: v4l2: Remove vidioc_g_ctrl callbackRicardo Ribalda
All the drivers either use the control framework or provide a vidioc_g_ext_ctrls callback. We can remove this callback. Thanks for your service! Signed-off-by: Ricardo Ribalda <ribalda@chromium.org> Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2025-03-05media: v4l2: Remove vidioc_queryctrl callbackRicardo Ribalda
All the drivers either use the control framework or provide a vidioc_query_ext_ctrl. We can remove this callback to reduce the temptation of new drivers to implement it. Signed-off-by: Ricardo Ribalda <ribalda@chromium.org> Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2025-03-05mm/slab: call kmalloc_noprof() unconditionally in kmalloc_array_noprof()Ye Bin
If 'n' or 'size' isn't builtin constant, we used to call __kmalloc() before commit 7bd230a26648 ("mm/slab: enable slab allocation tagging for kmalloc and friends"), which inadvertedly changed both paths to kmalloc_noprof(). As Harry Yoo points out we can just call kmalloc_noprof() unconditionally. If the compiler knows n and size are constants it doesn't guarantee that bytes will be also seen as constant, and that is the important test in kmalloc_noprof() anyway, so we can just defer to it always. [ vbabka@suse.cz: change as Harry suggested and adjust commit log ] Fixes: 7bd230a26648 ("mm/slab: enable slab allocation tagging for kmalloc and friends") Signed-off-by: Ye Bin <yebin10@huawei.com> Reviewed-by: Harry Yoo <harry.yoo@oracle.com> Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
2025-03-05drm/xe/uapi: Use hint for guc to set GT frequencyTejas Upadhyay
Allow user to provide a low latency hint. When set, KMD sends a hint to GuC which results in special handling for that process. SLPC will ramp the GT frequency aggressively every time it switches to this process. We need to enable the use of SLPC Compute strategy during init, but it will apply only to processes that set this bit during process creation. Improvement with this approach as below: Before, :~$ NEOReadDebugKeys=1 EnableDirectSubmission=0 clpeak --kernel-latency Platform: Intel(R) OpenCL Graphics Device: Intel(R) Graphics [0xe20b] Driver version : 24.52.0 (Linux x64) Compute units : 160 Clock frequency : 2850 MHz Kernel launch latency : 283.16 us After, :~$ NEOReadDebugKeys=1 EnableDirectSubmission=0 clpeak --kernel-latency Platform: Intel(R) OpenCL Graphics Device: Intel(R) Graphics [0xe20b] Driver version : 24.52.0 (Linux x64) Compute units : 160 Clock frequency : 2850 MHz Kernel launch latency : 63.38 us Compute PR: https://github.com/intel/compute-runtime/pull/794 Mesa PR: https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/33214 IGT PR: https://patchwork.freedesktop.org/patch/639989/ V10(Lucas): - Remove doc from drm-uapi.rst v9(Vinay): - remove extra line, align commit message v8(Vinay): - Add separate example for using low latency hint v7(Jose): - Update UMD PR - applicable to all gpus V6: - init flags, remove redundant flags check (MAuld) V5: - Move uapi doc to documentation and GuC ABI specific change (Rodrigo) - Modify logic to restrict exec queue flags (MAuld) V4: - To make it clear, dont use exec queue word (Vinay) - Correct typo in description of flag (Jose/Vinay) - rename set_strategy api and replace ctx with exec queue(Vinay) - Start with 0th bit to indentify user flags (Jose) V3: - Conver user flag to kernel internal flag and use (Oak) - Support query config for use to check kernel support (Jose) - Dont need to take runtime pm (Vinay) V2: - DRM_XE_EXEC_QUEUE_LOW_LATENCY_HINT 1 planned for other hint(Szymon) - Add motivation to description (Lucas) Acked-by: Lucas De Marchi <lucas.demarchi@intel.com> Reviewed-by: Vinay Belgaumkar <vinay.belgaumkar@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20250228070224.739295-2-tejas.upadhyay@intel.com Signed-off-by: Tejas Upadhyay <tejas.upadhyay@intel.com>
2025-03-04Merge branches 'docs.2025.02.04a', 'lazypreempt.2025.03.04a', ↵Boqun Feng
'misc.2025.03.04a', 'srcu.2025.02.05a' and 'torture.2025.02.05a'
2025-03-04rcu: Use _full() API to debug synchronize_rcu()Uladzislau Rezki (Sony)
Switch for using of get_state_synchronize_rcu_full() and poll_state_synchronize_rcu_full() pair to debug a normal synchronize_rcu() call. Just using "not" full APIs to identify if a grace period is passed or not might lead to a false-positive kernel splat. It can happen, because get_state_synchronize_rcu() compresses both normal and expedited states into one single unsigned long value, so a poll_state_synchronize_rcu() can miss GP-completion when synchronize_rcu()/synchronize_rcu_expedited() concurrently run. To address this, switch to poll_state_synchronize_rcu_full() and get_state_synchronize_rcu_full() APIs, which use separate variables for expedited and normal states. Reported-by: cheung wall <zzqq0103.hey@gmail.com> Closes: https://lore.kernel.org/lkml/Z5ikQeVmVdsWQrdD@pc636/T/ Fixes: 988f569ae041 ("rcu: Reduce synchronize_rcu() latency") Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com> Reviewed-by: Paul E. McKenney <paulmck@kernel.org> Link: https://lore.kernel.org/r/20250227131613.52683-3-urezki@gmail.com Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
2025-03-04Flush console log from kernel_power_off()Paul E. McKenney
Kernels built with CONFIG_PREEMPT_RT=y can lose significant console output and shutdown time, which hides shutdown-time RCU issues from rcutorture. Therefore, make pr_flush() public and invoke it after then last print in kernel_power_off(). [ paulmck: Apply John Ogness feedback. ] [ paulmck: Appy Sebastian Andrzej Siewior feedback. ] [ paulmck: Apply kernel test robot feedback. ] Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Reviewed-by: John Ogness <john.ogness@linutronix.de> Reviewed-by: Petr Mladek <pmladek@suse.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <senozhatsky@chromium.org> Link: https://lore.kernel.org/r/5f743488-dc2a-4f19-bdda-cf50b9314832@paulmck-laptop Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
2025-03-04rcu-tasks: Move RCU Tasks self-tests to core_initcall()Paul E. McKenney
The timer and hrtimer softirq processing has moved to dedicated threads for kernels built with CONFIG_IRQ_FORCED_THREADING=y. This results in timers not expiring until later in early boot, which in turn causes the RCU Tasks self-tests to hang in kernels built with CONFIG_PROVE_RCU=y, which further causes the entire kernel to hang. One fix would be to make timers work during this time, but there are no known users of RCU Tasks grace periods during that time, so no justification for the added complexity. Not yet, anyway. This commit therefore moves the call to rcu_init_tasks_generic() from kernel_init_freeable() to a core_initcall(). This works because the timer and hrtimer kthreads are created at early_initcall() time. Fixes: 49a17639508c3 ("softirq: Use a dedicated thread for timer wakeups on PREEMPT_RT.") Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Frederic Weisbecker <frederic@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Andrii Nakryiko <andrii@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: <linux-trace-kernel@vger.kernel.org> Tested-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
2025-03-04tcp: use RCU lookup in __inet_hash_connect()Eric Dumazet
When __inet_hash_connect() has to try many 4-tuples before finding an available one, we see a high spinlock cost from the many spin_lock_bh(&head->lock) performed in its loop. This patch adds an RCU lookup to avoid the spinlock cost. check_established() gets a new @rcu_lookup argument. First reason is to not make any changes while head->lock is not held. Second reason is to not make this RCU lookup a second time after the spinlock has been acquired. Tested: Server: ulimit -n 40000; neper/tcp_crr -T 200 -F 30000 -6 --nolog Client: ulimit -n 40000; neper/tcp_crr -T 200 -F 30000 -6 --nolog -c -H server Before series: utime_start=0.288582 utime_end=1.548707 stime_start=20.637138 stime_end=2002.489845 num_transactions=484453 latency_min=0.156279245 latency_max=20.922042756 latency_mean=1.546521274 latency_stddev=3.936005194 num_samples=312537 throughput=47426.00 perf top on the client: 49.54% [kernel] [k] _raw_spin_lock 25.87% [kernel] [k] _raw_spin_lock_bh 5.97% [kernel] [k] queued_spin_lock_slowpath 5.67% [kernel] [k] __inet_hash_connect 3.53% [kernel] [k] __inet6_check_established 3.48% [kernel] [k] inet6_ehashfn 0.64% [kernel] [k] rcu_all_qs After this series: utime_start=0.271607 utime_end=3.847111 stime_start=18.407684 stime_end=1997.485557 num_transactions=1350742 latency_min=0.014131929 latency_max=17.895073144 latency_mean=0.505675853 # Nice reduction of latency metrics latency_stddev=2.125164772 num_samples=307884 throughput=139866.80 # 190 % increase perf top on client: 56.86% [kernel] [k] __inet6_check_established 17.96% [kernel] [k] __inet_hash_connect 13.88% [kernel] [k] inet6_ehashfn 2.52% [kernel] [k] rcu_all_qs 2.01% [kernel] [k] __cond_resched 0.41% [kernel] [k] _raw_spin_lock Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Jason Xing <kerneljasonxing@gmail.com> Tested-by: Jason Xing <kerneljasonxing@gmail.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Link: https://patch.msgid.link/20250302124237.3913746-5-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-03-04tcp: add RCU management to inet_bind_bucketEric Dumazet
Add RCU protection to inet_bind_bucket structure. - Add rcu_head field to the structure definition. - Use kfree_rcu() at destroy time, and remove inet_bind_bucket_destroy() first argument. - Use hlist_del_rcu() and hlist_add_head_rcu() methods. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Jason Xing <kerneljasonxing@gmail.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Link: https://patch.msgid.link/20250302124237.3913746-4-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-03-04ppp: use IFF_NO_QUEUE in virtual interfacesQingfang Deng
For PPPoE, PPTP, and PPPoL2TP, the start_xmit() function directly forwards packets to the underlying network stack and never returns anything other than 1. So these interfaces do not require a qdisc, and the IFF_NO_QUEUE flag should be set. Introduces a direct_xmit flag in struct ppp_channel to indicate when IFF_NO_QUEUE should be applied. The flag is set in ppp_connect_channel() for relevant protocols. While at it, remove the usused latency member from struct ppp_channel. Signed-off-by: Qingfang Deng <dqfext@gmail.com> Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com> Link: https://patch.msgid.link/20250301135517.695809-1-dqfext@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-03-04PCI: hotplug: Inline pci_hp_{create,remove}_module_link()Lukas Wunner
For no apparent reason, the pci_hp_{create,remove}_module_link() helpers live in slot.c, even though they're only called from two functions in pci_hotplug_core.c. Inline the helpers to reduce code size and number of exported symbols. Link: https://lore.kernel.org/r/c207f03cfe32ae9002d9b453001a1dd63d9ab3fb.1740501868.git.lukas@wunner.de Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2025-03-04PCI: hotplug: Drop superfluous pci_hotplug_slot_listLukas Wunner
The PCI hotplug core keeps a list of all registered slots. Its sole purpose is to WARN() on slot removal if another slot is using the same name. But this can never happen because already on slot creation, an error is returned and multiple messages are emitted if a slot's name is duplicated: pci_hp_register() __pci_hp_register() __pci_hp_initialize() pci_create_slot() kobject_init_and_add() kobject_add_varg() kobject_add_internal() create_dir() sysfs_create_dir_ns() kernfs_create_dir_ns() sysfs_warn_dup() pr_warn("cannot create duplicate filename ...") pr_err("%s failed for %s with -EEXIST, ..."); Drop the superfluous list. Link: https://lore.kernel.org/r/603735bc50eb370bc7f1c358441ac671360bab25.1740501868.git.lukas@wunner.de Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2025-03-04ACPI: platform_profile: Add support for hidden choicesMario Limonciello
When two drivers don't support all the same profiles the legacy interface only exports the common profiles. This causes problems for cases where one driver uses low-power but another uses quiet because the result is that neither is exported to sysfs. To allow two drivers to disagree, add support for "hidden choices". Hidden choices are platform profiles that a driver supports to be compatible with the platform profile of another driver. Fixes: 688834743d67 ("ACPI: platform_profile: Allow multiple handlers") Reported-by: Antheas Kapenekakis <lkml@antheas.dev> Closes: https://lore.kernel.org/platform-driver-x86/e64b771e-3255-42ad-9257-5b8fc6c24ac9@gmx.de/T/#mc068042dd29df36c16c8af92664860fc4763974b Signed-off-by: Mario Limonciello <mario.limonciello@amd.com> Tested-by: Antheas Kapenekakis <lkml@antheas.dev> Tested-by: Derek J. Clark <derekjohn.clark@gmail.com> Acked-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://patch.msgid.link/20250228170155.2623386-2-superm1@kernel.org Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2025-03-04x86/percpu: Fix __per_cpu_hot_end markerUros Bizjak
Make __per_cpu_hot_end marker point to the end of the percpu cache hot data, not to the end of the percpu cache hot section. This fixes CONFIG_MPENTIUM4 case where X86_L1_CACHE_SHIFT is set to 7 (128 bytes). Also update assert message accordingly. Reported-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Uros Bizjak <ubizjak@gmail.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Brian Gerst <brgerst@gmail.com> Link: https://lore.kernel.org/r/20250304173455.89361-1-ubizjak@gmail.com Closes: https://lore.kernel.org/lkml/Z8a-NVJs-pm5W-mG@gmail.com/
2025-03-04x86/preempt: Move preempt count to percpu hot sectionBrian Gerst
No functional change. Signed-off-by: Brian Gerst <brgerst@gmail.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Uros Bizjak <ubizjak@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20250303165246.2175811-4-brgerst@gmail.com
2025-03-04percpu: Introduce percpu hot sectionBrian Gerst
Add a subsection to the percpu data for frequently accessed variables that should remain cached on each processor. These varables should not be accessed from other processors to avoid cacheline bouncing. This will replace the pcpu_hot struct on x86, and open up similar functionality to other architectures and the kernel core. Signed-off-by: Brian Gerst <brgerst@gmail.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Uros Bizjak <ubizjak@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20250303165246.2175811-2-brgerst@gmail.com
2025-03-04Merge branch 'x86/asm' into x86/core, to pick up dependent commitsIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2025-03-04fs/pipe: Read pipe->{head,tail} atomically outside pipe->mutexLinus Torvalds
pipe_readable(), pipe_writable(), and pipe_poll() can read "pipe->head" and "pipe->tail" outside of "pipe->mutex" critical section. When the head and the tail are read individually in that order, there is a window for interruption between the two reads in which both the head and the tail can be updated by concurrent readers and writers. One of the problematic scenarios observed with hackbench running multiple groups on a large server on a particular pipe inode is as follows: pipe->head = 36 pipe->tail = 36 hackbench-118762 [057] ..... 1029.550548: pipe_write: *wakes up: pipe not full* hackbench-118762 [057] ..... 1029.550548: pipe_write: head: 36 -> 37 [tail: 36] hackbench-118762 [057] ..... 1029.550548: pipe_write: *wake up next reader 118740* hackbench-118762 [057] ..... 1029.550548: pipe_write: *wake up next writer 118768* hackbench-118768 [206] ..... 1029.55055X: pipe_write: *writer wakes up* hackbench-118768 [206] ..... 1029.55055X: pipe_write: head = READ_ONCE(pipe->head) [37] ... CPU 206 interrupted (exact wakeup was not traced but 118768 did read head at 37 in traces) hackbench-118740 [057] ..... 1029.550558: pipe_read: *reader wakes up: pipe is not empty* hackbench-118740 [057] ..... 1029.550558: pipe_read: tail: 36 -> 37 [head = 37] hackbench-118740 [057] ..... 1029.550559: pipe_read: *pipe is empty; wakeup writer 118768* hackbench-118740 [057] ..... 1029.550559: pipe_read: *sleeps* hackbench-118766 [185] ..... 1029.550592: pipe_write: *New writer comes in* hackbench-118766 [185] ..... 1029.550592: pipe_write: head: 37 -> 38 [tail: 37] hackbench-118766 [185] ..... 1029.550592: pipe_write: *wakes up reader 118766* hackbench-118740 [185] ..... 1029.550598: pipe_read: *reader wakes up; pipe not empty* hackbench-118740 [185] ..... 1029.550599: pipe_read: tail: 37 -> 38 [head: 38] hackbench-118740 [185] ..... 1029.550599: pipe_read: *pipe is empty* hackbench-118740 [185] ..... 1029.550599: pipe_read: *reader sleeps; wakeup writer 118768* ... CPU 206 switches back to writer hackbench-118768 [206] ..... 1029.550601: pipe_write: tail = READ_ONCE(pipe->tail) [38] hackbench-118768 [206] ..... 1029.550601: pipe_write: pipe_full()? (u32)(37 - 38) >= 16? Yes hackbench-118768 [206] ..... 1029.550601: pipe_write: *writer goes back to sleep* [ Tasks 118740 and 118768 can then indefinitely wait on each other. ] The unsigned arithmetic in pipe_occupancy() wraps around when "pipe->tail > pipe->head" leading to pipe_full() returning true despite the pipe being empty. The case of genuine wraparound of "pipe->head" is handled since pipe buffer has data allowing readers to make progress until the pipe->tail wraps too after which the reader will wakeup a sleeping writer, however, mistaking the pipe to be full when it is in fact empty can lead to readers and writers waiting on each other indefinitely. This issue became more problematic and surfaced as a hang in hackbench after the optimization in commit aaec5a95d596 ("pipe_read: don't wake up the writer if the pipe is still full") significantly reduced the number of spurious wakeups of writers that had previously helped mask the issue. To avoid missing any updates between the reads of "pipe->head" and "pipe->write", unionize the two with a single unsigned long "pipe->head_tail" member that can be loaded atomically. Using "pipe->head_tail" to read the head and the tail ensures the lockless checks do not miss any updates to the head or the tail and since those two are only updated under "pipe->mutex", it ensures that the head is always ahead of, or equal to the tail resulting in correct calculations. [ prateek: commit log, testing on x86 platforms. ] Reported-and-debugged-by: Swapnil Sapkal <swapnil.sapkal@amd.com> Closes: https://lore.kernel.org/lkml/e813814e-7094-4673-bc69-731af065a0eb@amd.com/ Reported-by: Alexey Gladkov <legion@kernel.org> Closes: https://lore.kernel.org/all/Z8Wn0nTvevLRG_4m@example.org/ Fixes: 8cefc107ca54 ("pipe: Use head and tail pointers for the ring, not cursor and length") Tested-by: Swapnil Sapkal <swapnil.sapkal@amd.com> Reviewed-by: Oleg Nesterov <oleg@redhat.com> Tested-by: Alexey Gladkov <legion@kernel.org> Signed-off-by: K Prateek Nayak <kprateek.nayak@amd.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>