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2022-03-28Reinstate some of "swiotlb: rework "fix info leak with DMA_FROM_DEVICE""Linus Torvalds1-8/+0
Halil Pasic points out [1] that the full revert of that commit (revert in bddac7c1e02b), and that a partial revert that only reverts the problematic case, but still keeps some of the cleanups is probably better.  And that partial revert [2] had already been verified by Oleksandr Natalenko to also fix the issue, I had just missed that in the long discussion. So let's reinstate the cleanups from commit aa6f8dcbab47 ("swiotlb: rework "fix info leak with DMA_FROM_DEVICE""), and effectively only revert the part that caused problems. Link: https://lore.kernel.org/all/20220328013731.017ae3e3.pasic@linux.ibm.com/ [1] Link: https://lore.kernel.org/all/20220324055732.GB12078@lst.de/ [2] Link: https://lore.kernel.org/all/4386660.LvFx2qVVIh@natalenko.name/ [3] Suggested-by: Halil Pasic <pasic@linux.ibm.com> Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name> Cc: Christoph Hellwig" <hch@lst.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-26Revert "swiotlb: rework "fix info leak with DMA_FROM_DEVICE""Linus Torvalds1-0/+8
This reverts commit aa6f8dcbab473f3a3c7454b74caa46d36cdc5d13. It turns out this breaks at least the ath9k wireless driver, and possibly others. What the ath9k driver does on packet receive is to set up the DMA transfer with: int ath_rx_init(..) .. bf->bf_buf_addr = dma_map_single(sc->dev, skb->data, common->rx_bufsize, DMA_FROM_DEVICE); and then the receive logic (through ath_rx_tasklet()) will fetch incoming packets static bool ath_edma_get_buffers(..) .. dma_sync_single_for_cpu(sc->dev, bf->bf_buf_addr, common->rx_bufsize, DMA_FROM_DEVICE); ret = ath9k_hw_process_rxdesc_edma(ah, rs, skb->data); if (ret == -EINPROGRESS) { /*let device gain the buffer again*/ dma_sync_single_for_device(sc->dev, bf->bf_buf_addr, common->rx_bufsize, DMA_FROM_DEVICE); return false; } and it's worth noting how that first DMA sync: dma_sync_single_for_cpu(..DMA_FROM_DEVICE); is there to make sure the CPU can read the DMA buffer (possibly by copying it from the bounce buffer area, or by doing some cache flush). The iommu correctly turns that into a "copy from bounce bufer" so that the driver can look at the state of the packets. In the meantime, the device may continue to write to the DMA buffer, but we at least have a snapshot of the state due to that first DMA sync. But that _second_ DMA sync: dma_sync_single_for_device(..DMA_FROM_DEVICE); is telling the DMA mapping that the CPU wasn't interested in the area because the packet wasn't there. In the case of a DMA bounce buffer, that is a no-op. Note how it's not a sync for the CPU (the "for_device()" part), and it's not a sync for data written by the CPU (the "DMA_FROM_DEVICE" part). Or rather, it _should_ be a no-op. That's what commit aa6f8dcbab47 broke: it made the code bounce the buffer unconditionally, and changed the DMA_FROM_DEVICE to just unconditionally and illogically be DMA_TO_DEVICE. [ Side note: purely within the confines of the swiotlb driver it wasn't entirely illogical: The reason it did that odd DMA_FROM_DEVICE -> DMA_TO_DEVICE conversion thing is because inside the swiotlb driver, it uses just a swiotlb_bounce() helper that doesn't care about the whole distinction of who the sync is for - only which direction to bounce. So it took the "sync for device" to mean that the CPU must have been the one writing, and thought it meant DMA_TO_DEVICE. ] Also note how the commentary in that commit was wrong, probably due to that whole confusion, claiming that the commit makes the swiotlb code "bounce unconditionally (that is, also when dir == DMA_TO_DEVICE) in order do avoid synchronising back stale data from the swiotlb buffer" which is nonsensical for two reasons: - that "also when dir == DMA_TO_DEVICE" is nonsensical, as that was exactly when it always did - and should do - the bounce. - since this is a sync for the device (not for the CPU), we're clearly fundamentally not coping back stale data from the bounce buffers at all, because we'd be copying *to* the bounce buffers. So that commit was just very confused. It confused the direction of the synchronization (to the device, not the cpu) with the direction of the DMA (from the device). Reported-and-bisected-by: Oleksandr Natalenko <oleksandr@natalenko.name> Reported-by: Olha Cherevyk <olha.cherevyk@gmail.com> Cc: Halil Pasic <pasic@linux.ibm.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Kalle Valo <kvalo@kernel.org> Cc: Robin Murphy <robin.murphy@arm.com> Cc: Toke Høiland-Jørgensen <toke@toke.dk> Cc: Maxime Bizon <mbizon@freebox.fr> Cc: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22Merge tag 'folio-5.18c' of git://git.infradead.org/users/willy/pagecacheLinus Torvalds1-9/+9
Pull folio updates from Matthew Wilcox: - Rewrite how munlock works to massively reduce the contention on i_mmap_rwsem (Hugh Dickins): https://lore.kernel.org/linux-mm/8e4356d-9622-a7f0-b2c-f116b5f2efea@google.com/ - Sort out the page refcount mess for ZONE_DEVICE pages (Christoph Hellwig): https://lore.kernel.org/linux-mm/20220210072828.2930359-1-hch@lst.de/ - Convert GUP to use folios and make pincount available for order-1 pages. (Matthew Wilcox) - Convert a few more truncation functions to use folios (Matthew Wilcox) - Convert page_vma_mapped_walk to use PFNs instead of pages (Matthew Wilcox) - Convert rmap_walk to use folios (Matthew Wilcox) - Convert most of shrink_page_list() to use a folio (Matthew Wilcox) - Add support for creating large folios in readahead (Matthew Wilcox) * tag 'folio-5.18c' of git://git.infradead.org/users/willy/pagecache: (114 commits) mm/damon: minor cleanup for damon_pa_young selftests/vm/transhuge-stress: Support file-backed PMD folios mm/filemap: Support VM_HUGEPAGE for file mappings mm/readahead: Switch to page_cache_ra_order mm/readahead: Align file mappings for non-DAX mm/readahead: Add large folio readahead mm: Support arbitrary THP sizes mm: Make large folios depend on THP mm: Fix READ_ONLY_THP warning mm/filemap: Allow large folios to be added to the page cache mm: Turn can_split_huge_page() into can_split_folio() mm/vmscan: Convert pageout() to take a folio mm/vmscan: Turn page_check_references() into folio_check_references() mm/vmscan: Account large folios correctly mm/vmscan: Optimise shrink_page_list for non-PMD-sized folios mm/vmscan: Free non-shmem folios without splitting them mm/rmap: Constify the rmap_walk_control argument mm/rmap: Convert rmap_walk() to take a folio mm: Turn page_anon_vma() into folio_anon_vma() mm/rmap: Turn page_lock_anon_vma_read() into folio_lock_anon_vma_read() ...
2022-03-22Merge branch 'akpm' (patches from Andrew)Linus Torvalds1-2/+17
Merge updates from Andrew Morton: - A few misc subsystems: kthread, scripts, ntfs, ocfs2, block, and vfs - Most the MM patches which precede the patches in Willy's tree: kasan, pagecache, gup, swap, shmem, memcg, selftests, pagemap, mremap, sparsemem, vmalloc, pagealloc, memory-failure, mlock, hugetlb, userfaultfd, vmscan, compaction, mempolicy, oom-kill, migration, thp, cma, autonuma, psi, ksm, page-poison, madvise, memory-hotplug, rmap, zswap, uaccess, ioremap, highmem, cleanups, kfence, hmm, and damon. * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (227 commits) mm/damon/sysfs: remove repeat container_of() in damon_sysfs_kdamond_release() Docs/ABI/testing: add DAMON sysfs interface ABI document Docs/admin-guide/mm/damon/usage: document DAMON sysfs interface selftests/damon: add a test for DAMON sysfs interface mm/damon/sysfs: support DAMOS stats mm/damon/sysfs: support DAMOS watermarks mm/damon/sysfs: support schemes prioritization mm/damon/sysfs: support DAMOS quotas mm/damon/sysfs: support DAMON-based Operation Schemes mm/damon/sysfs: support the physical address space monitoring mm/damon/sysfs: link DAMON for virtual address spaces monitoring mm/damon: implement a minimal stub for sysfs-based DAMON interface mm/damon/core: add number of each enum type values mm/damon/core: allow non-exclusive DAMON start/stop Docs/damon: update outdated term 'regions update interval' Docs/vm/damon/design: update DAMON-Idle Page Tracking interference handling Docs/vm/damon: call low level monitoring primitives the operations mm/damon: remove unnecessary CONFIG_DAMON option mm/damon/paddr,vaddr: remove damon_{p,v}a_{target_valid,set_operations}() mm/damon/dbgfs-test: fix is_target_id() change ...
2022-03-22mm: document and polish read-ahead codeNeilBrown1-2/+17
Add some "big-picture" documentation for read-ahead and polish the code to make it fit this documentation. The meaning of ->async_size is clarified to match its name. i.e. Any request to ->readahead() has a sync part and an async part. The caller will wait for the sync pages to complete, but will not wait for the async pages. The first async page is still marked PG_readahead Note that the current function names page_cache_sync_ra() and page_cache_async_ra() are misleading. All ra request are partly sync and partly async, so either part can be empty. A page_cache_sync_ra() request will usually set ->async_size non-zero, implying it is not all synchronous. When a non-zero req_count is passed to page_cache_async_ra(), the implication is that some prefix of the request is synchronous, though the calculation made there is incorrect - I haven't tried to fix it. Link: https://lkml.kernel.org/r/164549983734.9187.11586890887006601405.stgit@noble.brown Signed-off-by: NeilBrown <neilb@suse.de> Cc: Anna Schumaker <Anna.Schumaker@Netapp.com> Cc: Chao Yu <chao@kernel.org> Cc: Darrick J. Wong <djwong@kernel.org> Cc: Ilya Dryomov <idryomov@gmail.com> Cc: Jaegeuk Kim <jaegeuk@kernel.org> Cc: Jan Kara <jack@suse.cz> Cc: Jeff Layton <jlayton@kernel.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: Lars Ellenberg <lars.ellenberg@linbit.com> Cc: Miklos Szeredi <miklos@szeredi.hu> Cc: Paolo Valente <paolo.valente@linaro.org> Cc: Philipp Reisner <philipp.reisner@linbit.com> Cc: Ryusuke Konishi <konishi.ryusuke@gmail.com> Cc: Trond Myklebust <trond.myklebust@hammerspace.com> Cc: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-21mm: Make compound_pincount always availableMatthew Wilcox (Oracle)1-9/+9
Move compound_pincount from the third page to the second page, which means it's available for all compound pages. That lets us delete hpage_pincount_available(). On 32-bit systems, there isn't enough space for both compound_pincount and compound_nr in the second page (it would collide with page->private, which is in use for pages in the swap cache), so revert the optimisation of storing both compound_order and compound_nr on 32-bit systems. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: John Hubbard <jhubbard@nvidia.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Reviewed-by: William Kucharski <william.kucharski@oracle.com>
2022-03-07swiotlb: rework "fix info leak with DMA_FROM_DEVICE"Halil Pasic1-8/+0
Unfortunately, we ended up merging an old version of the patch "fix info leak with DMA_FROM_DEVICE" instead of merging the latest one. Christoph (the swiotlb maintainer), he asked me to create an incremental fix (after I have pointed this out the mix up, and asked him for guidance). So here we go. The main differences between what we got and what was agreed are: * swiotlb_sync_single_for_device is also required to do an extra bounce * We decided not to introduce DMA_ATTR_OVERWRITE until we have exploiters * The implantation of DMA_ATTR_OVERWRITE is flawed: DMA_ATTR_OVERWRITE must take precedence over DMA_ATTR_SKIP_CPU_SYNC Thus this patch removes DMA_ATTR_OVERWRITE, and makes swiotlb_sync_single_for_device() bounce unconditionally (that is, also when dir == DMA_TO_DEVICE) in order do avoid synchronising back stale data from the swiotlb buffer. Let me note, that if the size used with dma_sync_* API is less than the size used with dma_[un]map_*, under certain circumstances we may still end up with swiotlb not being transparent. In that sense, this is no perfect fix either. To get this bullet proof, we would have to bounce the entire mapping/bounce buffer. For that we would have to figure out the starting address, and the size of the mapping in swiotlb_sync_single_for_device(). While this does seem possible, there seems to be no firm consensus on how things are supposed to work. Signed-off-by: Halil Pasic <pasic@linux.ibm.com> Fixes: ddbd89deb7d3 ("swiotlb: fix info leak with DMA_FROM_DEVICE") Cc: stable@vger.kernel.org Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-02-14swiotlb: fix info leak with DMA_FROM_DEVICEHalil Pasic1-0/+8
The problem I'm addressing was discovered by the LTP test covering cve-2018-1000204. A short description of what happens follows: 1) The test case issues a command code 00 (TEST UNIT READY) via the SG_IO interface with: dxfer_len == 524288, dxdfer_dir == SG_DXFER_FROM_DEV and a corresponding dxferp. The peculiar thing about this is that TUR is not reading from the device. 2) In sg_start_req() the invocation of blk_rq_map_user() effectively bounces the user-space buffer. As if the device was to transfer into it. Since commit a45b599ad808 ("scsi: sg: allocate with __GFP_ZERO in sg_build_indirect()") we make sure this first bounce buffer is allocated with GFP_ZERO. 3) For the rest of the story we keep ignoring that we have a TUR, so the device won't touch the buffer we prepare as if the we had a DMA_FROM_DEVICE type of situation. My setup uses a virtio-scsi device and the buffer allocated by SG is mapped by the function virtqueue_add_split() which uses DMA_FROM_DEVICE for the "in" sgs (here scatter-gather and not scsi generics). This mapping involves bouncing via the swiotlb (we need swiotlb to do virtio in protected guest like s390 Secure Execution, or AMD SEV). 4) When the SCSI TUR is done, we first copy back the content of the second (that is swiotlb) bounce buffer (which most likely contains some previous IO data), to the first bounce buffer, which contains all zeros. Then we copy back the content of the first bounce buffer to the user-space buffer. 5) The test case detects that the buffer, which it zero-initialized, ain't all zeros and fails. One can argue that this is an swiotlb problem, because without swiotlb we leak all zeros, and the swiotlb should be transparent in a sense that it does not affect the outcome (if all other participants are well behaved). Copying the content of the original buffer into the swiotlb buffer is the only way I can think of to make swiotlb transparent in such scenarios. So let's do just that if in doubt, but allow the driver to tell us that the whole mapped buffer is going to be overwritten, in which case we can preserve the old behavior and avoid the performance impact of the extra bounce. Signed-off-by: Halil Pasic <pasic@linux.ibm.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2022-01-27Documentation: core-api: entry: Add comments about nestingNicolas Saenz Julienne1-0/+18
The topic of nesting and reentrancy in the context of early entry code hasn't been addressed so far. So do it. Signed-off-by: Nicolas Saenz Julienne <nsaenzju@redhat.com> Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Reviewed-by: Paul E. McKenney <paulmck@kernel.org> Link: https://lore.kernel.org/r/20220110105044.94423-2-nsaenzju@redhat.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-01-27Documentation: Fill the gaps about entry/noinstr constraintsThomas Gleixner2-0/+269
The entry/exit handling for exceptions, interrupts, syscalls and KVM is not really documented except for some comments. Fill the gaps. Signed-off-by: Thomas Gleixner <tglx@linutronix.de Co-developed-by: Nicolas Saenz Julienne <nsaenzju@redhat.com> Signed-off-by: Nicolas Saenz Julienne <nsaenzju@redhat.com> Reviewed-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Paul E. McKenney <paulmck@kernel.org> ---- Changes since v3: - s/nointr/noinstr/ Changes since v2: - No big content changes, just style corrections, so it should be pretty clean at this stage. In the light of this, I kept Mark's Reviewed-by. - Paul's style and paragraph re-writes - Randy's style comments - Add links to transition type sections Documentation/core-api/entry.rst | 261 +++++++++++++++++++++++++++++++ Documentation/core-api/index.rst | 8 + 2 files changed, 269 insertions(+) create mode 100644 Documentation/core-api/entry.rst Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Link: https://lore.kernel.org/r/20220110105044.94423-1-nsaenzju@redhat.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-01-12Merge tag 'iomap-5.17' of git://git.infradead.org/users/willy/linuxLinus Torvalds1-0/+1
Pull iomap updates from Matthew Wilcox: "Convert xfs/iomap to use folios. This should be all that is needed for XFS to use large folios. There is no code in this pull request to create large folios, but no additional changes should be needed to XFS or iomap once they are created. Usually this would have come from Darrick, and we had intended that it would come that route. Between the holidays and various things which Darrick needed to work on, he asked if I could send things directly. There weren't any other iomap patches pending for this release, which probably also played a role" * tag 'iomap-5.17' of git://git.infradead.org/users/willy/linux: (26 commits) iomap: Inline __iomap_zero_iter into its caller xfs: Support large folios iomap: Support large folios in invalidatepage iomap: Convert iomap_migrate_page() to use folios iomap: Convert iomap_add_to_ioend() to take a folio iomap: Simplify iomap_do_writepage() iomap: Simplify iomap_writepage_map() iomap,xfs: Convert ->discard_page to ->discard_folio iomap: Convert iomap_write_end_inline to take a folio iomap: Convert iomap_write_begin() and iomap_write_end() to folios iomap: Convert __iomap_zero_iter to use a folio iomap: Allow iomap_write_begin() to be called with the full length iomap: Convert iomap_page_mkwrite to use a folio iomap: Convert readahead and readpage to use a folio iomap: Convert iomap_read_inline_data to take a folio iomap: Use folio offsets instead of page offsets iomap: Convert bio completions to use folios iomap: Pass the iomap_page into iomap_set_range_uptodate iomap: Add iomap_invalidate_folio iomap: Convert iomap_releasepage to use a folio ...
2022-01-12Merge tag 'driver-core-5.17-rc1' of ↵Linus Torvalds1-9/+7
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core updates from Greg KH: "Here is the set of changes for the driver core for 5.17-rc1. Lots of little things here, including: - kobj_type cleanups - auxiliary_bus documentation updates - auxiliary_device conversions for some drivers (relevant subsystems all have provided acks for these) - kernfs lock contention reduction for some workloads - other tiny cleanups and changes. All of these have been in linux-next for a while with no reported issues" * tag 'driver-core-5.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (43 commits) kobject documentation: remove default_attrs information drivers/firmware: Add missing platform_device_put() in sysfb_create_simplefb debugfs: lockdown: Allow reading debugfs files that are not world readable driver core: Make bus notifiers in right order in really_probe() driver core: Move driver_sysfs_remove() after driver_sysfs_add() firmware: edd: remove empty default_attrs array firmware: dmi-sysfs: use default_groups in kobj_type qemu_fw_cfg: use default_groups in kobj_type firmware: memmap: use default_groups in kobj_type sh: sq: use default_groups in kobj_type headers/uninline: Uninline single-use function: kobject_has_children() devtmpfs: mount with noexec and nosuid driver core: Simplify async probe test code by using ktime_ms_delta() nilfs2: use default_groups in kobj_type kobject: remove kset from struct kset_uevent_ops callbacks driver core: make kobj_type constant. driver core: platform: document registration-failure requirement vdpa/mlx5: Use auxiliary_device driver data helpers net/mlx5e: Use auxiliary_device driver data helpers soundwire: intel: Use auxiliary_device driver data helpers ...
2022-01-07kobject documentation: remove default_attrs informationGreg Kroah-Hartman1-3/+2
Since commit aa30f47cf666 ("kobject: Add support for default attribute groups to kobj_type") we have been encouraging the use of default_groups instead of default_attrs, so reflect that information in the documentation as well so that no new users get added while the kernel is converted over to not use this field anymore. Cc: "Rafael J. Wysocki" <rafael@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: linux-doc@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: https://lore.kernel.org/r/20220104105024.1014313-1-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-12-28kobject: remove kset from struct kset_uevent_ops callbacksGreg Kroah-Hartman1-4/+3
There is no need to pass the pointer to the kset in the struct kset_uevent_ops callbacks as no one uses it, so just remove that pointer entirely. Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Wedson Almeida Filho <wedsonaf@google.com> Link: https://lore.kernel.org/r/20211227163924.3970661-1-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-12-27driver core: make kobj_type constant.Wedson Almeida Filho1-2/+2
This way instances of kobj_type (which contain function pointers) can be stored in .rodata, which means that they cannot be [easily/accidentally] modified at runtime. Signed-off-by: Wedson Almeida Filho <wedsonaf@google.com> Link: https://lore.kernel.org/r/20211224231345.777370-1-wedsonaf@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-12-16block: Add bio_for_each_folio_all()Matthew Wilcox (Oracle)1-0/+1
Allow callers to iterate over each folio instead of each page. The bio need not have been constructed using folios originally. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Jens Axboe <axboe@kernel.dk> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-11-29block: remove blk-exec.cChristoph Hellwig1-3/+0
All this code is tightly coupled to the blk-mq core, so move it there. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Link: https://lore.kernel.org/r/20211117061404.331732-4-hch@lst.de [axboe: remove doc generation for blk-exec.c] Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-11-06Merge branch 'akpm' (patches from Andrew)Linus Torvalds1-3/+0
Merge misc updates from Andrew Morton: "257 patches. Subsystems affected by this patch series: scripts, ocfs2, vfs, and mm (slab-generic, slab, slub, kconfig, dax, kasan, debug, pagecache, gup, swap, memcg, pagemap, mprotect, mremap, iomap, tracing, vmalloc, pagealloc, memory-failure, hugetlb, userfaultfd, vmscan, tools, memblock, oom-kill, hugetlbfs, migration, thp, readahead, nommu, ksm, vmstat, madvise, memory-hotplug, rmap, zsmalloc, highmem, zram, cleanups, kfence, and damon)" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (257 commits) mm/damon: remove return value from before_terminate callback mm/damon: fix a few spelling mistakes in comments and a pr_debug message mm/damon: simplify stop mechanism Docs/admin-guide/mm/pagemap: wordsmith page flags descriptions Docs/admin-guide/mm/damon/start: simplify the content Docs/admin-guide/mm/damon/start: fix a wrong link Docs/admin-guide/mm/damon/start: fix wrong example commands mm/damon/dbgfs: add adaptive_targets list check before enable monitor_on mm/damon: remove unnecessary variable initialization Documentation/admin-guide/mm/damon: add a document for DAMON_RECLAIM mm/damon: introduce DAMON-based Reclamation (DAMON_RECLAIM) selftests/damon: support watermarks mm/damon/dbgfs: support watermarks mm/damon/schemes: activate schemes based on a watermarks mechanism tools/selftests/damon: update for regions prioritization of schemes mm/damon/dbgfs: support prioritization weights mm/damon/vaddr,paddr: support pageout prioritization mm/damon/schemes: prioritize regions within the quotas mm/damon/selftests: support schemes quotas mm/damon/dbgfs: support quotas of schemes ...
2021-11-06mm/memory_hotplug: remove HIGHMEM leftoversDavid Hildenbrand1-3/+0
We don't support CONFIG_MEMORY_HOTPLUG on 32 bit and consequently not HIGHMEM. Let's remove any leftover code -- including the unused "status_change_nid_high" field part of the memory notifier. Link: https://lkml.kernel.org/r/20210929143600.49379-5-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Oscar Salvador <osalvador@suse.de> Cc: Alex Shi <alexs@kernel.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Cc: Shuah Khan <shuah@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-11-02Merge branch 'for-5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wqLinus Torvalds1-4/+17
Pull workqueue updates from Tejun Heo: "Nothing too interesting. An optimization to short-circuit noop cpumask updates, debug dump code reorg, and doc update" * 'for-5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: workqueue: doc: Call out the non-reentrance conditions workqueue: Introduce show_one_worker_pool and show_one_workqueue. workqueue: make sysfs of unbound kworker cpumask more clever
2021-11-02Merge tag 'printk-for-5.16' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux Pull printk updates from Petr Mladek: - Extend %pGp print format to print hex value of the page flags - Use kvmalloc instead of kmalloc to allocate devkmsg buffers - Misc cleanup and warning fixes * tag 'printk-for-5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux: vsprintf: Update %pGp documentation about that it prints hex value lib/vsprintf.c: Amend static asserts for format specifier flags vsprintf: Make %pGp print the hex value test_printf: Append strings more efficiently test_printf: Remove custom appending of '|' test_printf: Remove separate page_flags variable test_printf: Make pft array const ia64: don't do IA64_CMPXCHG_DEBUG without CONFIG_PRINTK printk: use gnu_printf format attribute for printk_sprint() printk: avoid -Wsometimes-uninitialized warning printk: use kvmalloc instead of kmalloc for devkmsg_user
2021-11-01Merge tag 'irq-core-2021-10-31' of ↵Linus Torvalds1-3/+0
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq updates from Thomas Gleixner: "Updates for the interrupt subsystem: Core changes: - Prevent a potential deadlock when initial priority is assigned to a newly created interrupt thread. A recent change to plug a race between cpuset and __sched_setscheduler() introduced a new lock dependency which is now triggered. Break the lock dependency chain by moving the priority assignment to the thread function. - A couple of small updates to make the irq core RT safe. - Confine the irq_cpu_online/offline() API to the only left unfixable user Cavium Octeon so that it does not grow new usage. - A small documentation update Driver changes: - A large cross architecture rework to move irq_enter/exit() into the architecture code to make addressing the NOHZ_FULL/RCU issues simpler. - The obligatory new irq chip driver for Microchip EIC - Modularize a few irq chip drivers - Expand usage of devm_*() helpers throughout the driver code - The usual small fixes and improvements all over the place" * tag 'irq-core-2021-10-31' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (53 commits) h8300: Fix linux/irqchip.h include mess dt-bindings: irqchip: renesas-irqc: Document r8a774e1 bindings MIPS: irq: Avoid an unused-variable error genirq: Hide irq_cpu_{on,off}line() behind a deprecated option irqchip/mips-gic: Get rid of the reliance on irq_cpu_online() MIPS: loongson64: Drop call to irq_cpu_offline() irq: remove handle_domain_{irq,nmi}() irq: remove CONFIG_HANDLE_DOMAIN_IRQ_IRQENTRY irq: riscv: perform irqentry in entry code irq: openrisc: perform irqentry in entry code irq: csky: perform irqentry in entry code irq: arm64: perform irqentry in entry code irq: arm: perform irqentry in entry code irq: add a (temporary) CONFIG_HANDLE_DOMAIN_IRQ_IRQENTRY irq: nds32: avoid CONFIG_HANDLE_DOMAIN_IRQ irq: arc: avoid CONFIG_HANDLE_DOMAIN_IRQ irq: add generic_handle_arch_irq() irq: unexport handle_irq_desc() irq: simplify handle_domain_{irq,nmi}() irq: mips: simplify do_domain_IRQ() ...
2021-11-01vsprintf: Update %pGp documentation about that it prints hex valuePetr Mladek1-1/+1
The commit 23efd0804c0a869dfb1e7 ("vsprintf: Make %pGp print the hex value") changed the behavior of %pGp printk format. Update the documentation accordingly. Fixes: 23efd0804c0a869dfb1e7 ("vsprintf: Make %pGp print the hex value") Reviewed-by: Yafang Shao <laoar.shao@gmail.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/YXlKqCPY9suM4mfT@alley
2021-10-26irq: remove handle_domain_{irq,nmi}()Mark Rutland1-3/+0
Now that entry code handles IRQ entry (including setting the IRQ regs) before calling irqchip code, irqchip code can safely call generic_handle_domain_irq(), and there's no functional reason for it to call handle_domain_irq(). Let's cement this split of responsibility and remove handle_domain_irq() entirely, updating irqchip drivers to call generic_handle_domain_irq(). For consistency, handle_domain_nmi() is similarly removed and replaced with a generic_handle_domain_nmi() function which also does not perform any entry logic. Previously handle_domain_{irq,nmi}() had a WARN_ON() which would fire when they were called in an inappropriate context. So that we can identify similar issues going forward, similar WARN_ON_ONCE() logic is added to the generic_handle_*() functions, and comments are updated for clarity and consistency. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Marc Zyngier <maz@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de>
2021-10-25workqueue: doc: Call out the non-reentrance conditionsBoqun Feng1-4/+17
The current doc of workqueue API suggests that work items are non-reentrant: any work item is guaranteed to be executed by at most one worker system-wide at any given time. However this is not true, the following case can cause a work item W executed by two workers at the same time: queue_work_on(0, WQ1, W); // after a worker picks up W and clear the pending bit queue_work_on(1, WQ2, W); // workers on CPU0 and CPU1 will execute W in the same time. , which means the non-reentrance of a work item is conditional, and Lai Jiangshan provided a nice summary[1] of the conditions, therefore use it to describe a work item instance and improve the doc. [1]: https://lore.kernel.org/lkml/CAJhGHyDudet_xyNk=8xnuO2==o-u06s0E0GZVP4Q67nmQ84Ceg@mail.gmail.com/ Suggested-by: Matthew Wilcox <willy@infradead.org> Suggested-by: Tejun Heo <tj@kernel.org> Signed-off-by: Boqun Feng <boqun.feng@gmail.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2021-10-18mm: Add flush_dcache_folio()Matthew Wilcox (Oracle)1-0/+6
This is a default implementation which calls flush_dcache_page() on each page in the folio. If architectures can do better, they should implement their own version of it. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Acked-by: Vlastimil Babka <vbabka@suse.cz>
2021-09-27mm/util: Add folio_mapping() and folio_file_mapping()Matthew Wilcox (Oracle)1-0/+2
These are the folio equivalent of page_mapping() and page_file_mapping(). Add an out-of-line page_mapping() wrapper around folio_mapping() in order to prevent the page_folio() call from bloating every caller of page_mapping(). Adjust page_file_mapping() and page_mapping_file() to use folios internally. Rename __page_file_mapping() to swapcache_mapping() and change it to take a folio. This ends up saving 122 bytes of text overall. folio_mapping() is 45 bytes shorter than page_mapping() was, but the new page_mapping() wrapper is 30 bytes. The major reduction is a few bytes less in dozens of nfs functions (which call page_file_mapping()). Most of these appear to be a slight change in gcc's register allocation decisions, which allow: 48 8b 56 08 mov 0x8(%rsi),%rdx 48 8d 42 ff lea -0x1(%rdx),%rax 83 e2 01 and $0x1,%edx 48 0f 44 c6 cmove %rsi,%rax to become: 48 8b 46 08 mov 0x8(%rsi),%rax 48 8d 78 ff lea -0x1(%rax),%rdi a8 01 test $0x1,%al 48 0f 44 fe cmove %rsi,%rdi for a reduction of a single byte. Once the NFS client is converted to use folios, this entire sequence will disappear. Also add folio_mapping() documentation. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Jeff Layton <jlayton@kernel.org> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: William Kucharski <william.kucharski@oracle.com> Reviewed-by: David Howells <dhowells@redhat.com>
2021-09-27mm/lru: Add folio LRU functionsMatthew Wilcox (Oracle)1-0/+1
Handle arbitrary-order folios being added to the LRU. By definition, all pages being added to the LRU were already head or base pages, but call page_folio() on them anyway to get the type right and avoid the buried calls to compound_head(). Saves 783 bytes of kernel text; no functions grow. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Yu Zhao <yuzhao@google.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Howells <dhowells@redhat.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Mike Rapoport <rppt@linux.ibm.com> Acked-by: Vlastimil Babka <vbabka@suse.cz>
2021-09-27mm: Add folio reference count functionsMatthew Wilcox (Oracle)1-0/+1
These functions mirror their page reference counterparts. Also add the kernel-doc to the mm-api and correct the return type of page_ref_add_unless() to bool. No change to generated code. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Jeff Layton <jlayton@kernel.org> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: William Kucharski <william.kucharski@oracle.com> Reviewed-by: David Howells <dhowells@redhat.com> Acked-by: Mike Rapoport <rppt@linux.ibm.com>
2021-09-27mm: Introduce struct folioMatthew Wilcox (Oracle)1-0/+1
A struct folio is a new abstraction to replace the venerable struct page. A function which takes a struct folio argument declares that it will operate on the entire (possibly compound) page, not just PAGE_SIZE bytes. In return, the caller guarantees that the pointer it is passing does not point to a tail page. No change to generated code. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Acked-by: Jeff Layton <jlayton@kernel.org> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: William Kucharski <william.kucharski@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Howells <dhowells@redhat.com> Acked-by: Mike Rapoport <rppt@linux.ibm.com>
2021-09-24Merge tag 'irqchip-fixes-5.15-1' of ↵Thomas Gleixner1-2/+3
git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/urgent Pull irqchip fixes from Marc Zyngier: - Work around a bad GIC integration on a Renesas platform, where the interconnect cannot deal with byte-sized MMIO accesses - Cleanup another Renesas driver abusing the comma operator - Fix a potential GICv4 memory leak on an error path - Make the type of 'size' consistent with the rest of the code in __irq_domain_add() - Fix a regression in the Armada 370-XP IPI path - Fix the build for the obviously unloved goldfish-pic - Some documentation fixes Link: https://lore.kernel.org/r/20210924090933.2766857-1-maz@kernel.org
2021-09-12Merge tag 'smp-urgent-2021-09-12' of ↵Linus Torvalds1-99/+480
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull CPU hotplug updates from Thomas Gleixner: "Updates for the SMP and CPU hotplug: - Remove DEFINE_SMP_CALL_CACHE_FUNCTION() which is a left over of the original hotplug code and now causing trouble with the ARM64 cache topology setup due to the pointless SMP function call. It's not longer required as the hotplug callbacks are guaranteed to be invoked on the upcoming CPU. - Remove the deprecated and now unused CPU hotplug functions - Rewrite the CPU hotplug API documentation" * tag 'smp-urgent-2021-09-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: Documentation: core-api/cpuhotplug: Rewrite the API section cpu/hotplug: Remove deprecated CPU-hotplug functions. thermal: Replace deprecated CPU-hotplug functions. drivers: base: cacheinfo: Get rid of DEFINE_SMP_CALL_CACHE_FUNCTION()
2021-09-11Merge tag 'block-5.15-2021-09-11' of git://git.kernel.dk/linux-blockLinus Torvalds1-0/+3
Pull block fixes from Jens Axboe: - NVMe pull request from Christoph: - fix nvmet command set reporting for passthrough controllers (Adam Manzanares) - update a MAINTAINERS email address (Chaitanya Kulkarni) - set QUEUE_FLAG_NOWAIT for nvme-multipth (me) - handle errors from add_disk() (Luis Chamberlain) - update the keep alive interval when kato is modified (Tatsuya Sasaki) - fix a buffer overrun in nvmet_subsys_attr_serial (Hannes Reinecke) - do not reset transport on data digest errors in nvme-tcp (Daniel Wagner) - only call synchronize_srcu when clearing current path (Daniel Wagner) - revalidate paths during rescan (Hannes Reinecke) - Split out the fs/block_dev into block/fops.c and block/bdev.c, which has been long overdue. Do this now before -rc1, to avoid annoying conflicts due to this (Christoph) - blk-throtl use-after-free fix (Li) - Improve plug depth for multi-device plugs, greatly increasing md resync performance (Song) - blkdev_show() locking fix (Tetsuo) - n64cart error check fix (Yang) * tag 'block-5.15-2021-09-11' of git://git.kernel.dk/linux-block: n64cart: fix return value check in n64cart_probe() blk-mq: allow 4x BLK_MAX_REQUEST_COUNT at blk_plug for multiple_queues block: move fs/block_dev.c to block/bdev.c block: split out operations on block special files blk-throttle: fix UAF by deleteing timer in blk_throtl_exit() block: genhd: don't call blkdev_show() with major_names_lock held nvme: update MAINTAINERS email address nvme: add error handling support for add_disk() nvme: only call synchronize_srcu when clearing current path nvme: update keep alive interval when kato is modified nvme-tcp: Do not reset transport on data digest errors nvmet: fixup buffer overrun in nvmet_subsys_attr_serial() nvmet: return bool from nvmet_passthru_ctrl and nvmet_is_passthru_req nvmet: looks at the passthrough controller when initializing CAP nvme: move nvme_multi_css into nvme.h nvme-multipath: revalidate paths during rescan nvme-multipath: set QUEUE_FLAG_NOWAIT
2021-09-11Documentation: core-api/cpuhotplug: Rewrite the API sectionThomas Gleixner1-99/+480
Dave stumbled over the incomplete and confusing documentation of the CPU hotplug API. Rewrite it, add the missing function documentations and correct the existing ones. Reported-by: Dave Chinner <david@fromorbit.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20210909123212.489059409@linutronix.de
2021-09-07block: move fs/block_dev.c to block/bdev.cChristoph Hellwig1-0/+3
Move it together with the rest of the block layer. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20210907141303.1371844-3-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-09-03Merge branch 'akpm' (patches from Andrew)Linus Torvalds1-49/+37
Merge misc updates from Andrew Morton: "173 patches. Subsystems affected by this series: ia64, ocfs2, block, and mm (debug, pagecache, gup, swap, shmem, memcg, selftests, pagemap, mremap, bootmem, sparsemem, vmalloc, kasan, pagealloc, memory-failure, hugetlb, userfaultfd, vmscan, compaction, mempolicy, memblock, oom-kill, migration, ksm, percpu, vmstat, and madvise)" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (173 commits) mm/madvise: add MADV_WILLNEED to process_madvise() mm/vmstat: remove unneeded return value mm/vmstat: simplify the array size calculation mm/vmstat: correct some wrong comments mm/percpu,c: remove obsolete comments of pcpu_chunk_populated() selftests: vm: add COW time test for KSM pages selftests: vm: add KSM merging time test mm: KSM: fix data type selftests: vm: add KSM merging across nodes test selftests: vm: add KSM zero page merging test selftests: vm: add KSM unmerge test selftests: vm: add KSM merge test mm/migrate: correct kernel-doc notation mm: wire up syscall process_mrelease mm: introduce process_mrelease system call memblock: make memblock_find_in_range method private mm/mempolicy.c: use in_task() in mempolicy_slab_node() mm/mempolicy: unify the create() func for bind/interleave/prefer-many policies mm/mempolicy: advertise new MPOL_PREFERRED_MANY mm/hugetlb: add support for mempolicy MPOL_PREFERRED_MANY ...
2021-09-03mm: remove flush_kernel_dcache_pageChristoph Hellwig1-49/+37
flush_kernel_dcache_page is a rather confusing interface that implements a subset of flush_dcache_page by not being able to properly handle page cache mapped pages. The only callers left are in the exec code as all other previous callers were incorrect as they could have dealt with page cache pages. Replace the calls to flush_kernel_dcache_page with calls to flush_dcache_page, which for all architectures does either exactly the same thing, can contains one or more of the following: 1) an optimization to defer the cache flush for page cache pages not mapped into userspace 2) additional flushing for mapped page cache pages if cache aliases are possible Link: https://lkml.kernel.org/r/20210712060928.4161649-7-hch@lst.de Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Cc: Alex Shi <alexs@kernel.org> Cc: Geoff Levand <geoff@infradead.org> Cc: Greentime Hu <green.hu@gmail.com> Cc: Guo Ren <guoren@kernel.org> Cc: Helge Deller <deller@gmx.de> Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com> Cc: Nick Hu <nickhu@andestech.com> Cc: Paul Cercueil <paul@crapouillou.net> Cc: Rich Felker <dalias@libc.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Ulf Hansson <ulf.hansson@linaro.org> Cc: Vincent Chen <deanbo422@gmail.com> Cc: Yoshinori Sato <ysato@users.osdn.me> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03Documentation: Fix irq-domain.rst build warningMarc Zyngier1-2/+3
Correctly escape the * not to be used as emphasis. Also take this opportunity to clarify the fate of the rest of the legacy APIs. Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20210903085343.923036-1-maz@kernel.org
2021-09-01Merge tag 'docs-5.15' of git://git.lwn.net/linuxLinus Torvalds2-14/+25
Pull documentation updates from Jonathan Corbet: "Yet another set of documentation changes: - A reworking of PDF generation to yield better results for documents using CJK fonts in particular. - A new set of translations into traditional Chinese, a dialect for which I am assured there is a community of interested readers. - A lot more regular Chinese translation work as well. ... plus the usual assortment of updates, fixes, typo tweaks, etc" * tag 'docs-5.15' of git://git.lwn.net/linux: (55 commits) docs: sphinx-requirements: Move sphinx_rtd_theme to top docs: pdfdocs: Enable language-specific font choice of zh_TW translations docs: pdfdocs: Teach xeCJK about character classes of quotation marks docs: pdfdocs: Permit AutoFakeSlant for CJK fonts docs: pdfdocs: One-half spacing for CJK translations docs: pdfdocs: Add conf.py local to translations for ascii-art alignment docs: pdfdocs: Preserve inter-phrase space in Korean translations docs: pdfdocs: Choose Serif font as CJK mainfont if possible docs: pdfdocs: Add CJK-language-specific font settings docs: pdfdocs: Refactor config for CJK document scripts/kernel-doc: Override -Werror from KCFLAGS with KDOC_WERROR docs/zh_CN: Add zh_CN/accounting/psi.rst doc: align Italian translation Documentation/features/vm: riscv supports THP now docs/zh_CN: add infiniband user_verbs translation docs/zh_CN: add infiniband user_mad translation docs/zh_CN: add infiniband tag_matching translation docs/zh_CN: add infiniband sysfs translation docs/zh_CN: add infiniband opa_vnic translation docs/zh_CN: add infiniband ipoib translation ...
2021-09-01Merge tag 'printk-for-5.15' of ↵Linus Torvalds1-4/+1
git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux Pull printk updates from Petr Mladek: - Optionally, provide an index of possible printk messages via <debugfs>/printk/index/. It can be used when monitoring important kernel messages on a farm of various hosts. The monitor has to be updated when some messages has changed or are not longer available by a newly deployed kernel. - Add printk.console_no_auto_verbose boot parameter. It allows to generate crash dump even with slow consoles in a reasonable time frame. - Remove printk_safe buffers. The messages are always stored directly to the main logbuffer, even in NMI or recursive context. Also it allows to serialize syslog operations by a mutex instead of a spin lock. - Misc clean up and build fixes. * tag 'printk-for-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux: printk/index: Fix -Wunused-function warning lib/nmi_backtrace: Serialize even messages about idle CPUs printk: Add printk.console_no_auto_verbose boot parameter printk: Remove console_silent() lib/test_scanf: Handle n_bits == 0 in random tests printk: syslog: close window between wait and read printk: convert @syslog_lock to mutex printk: remove NMI tracking printk: remove safe buffers printk: track/limit recursion lib/nmi_backtrace: explicitly serialize banner and regs printk: Move the printk() kerneldoc comment to its new home printk/index: Fix warning about missing prototypes MIPS/asm/printk: Fix build failure caused by printk printk: index: Add indexing support to dev_printk printk: Userspace format indexing support printk: Rework parse_prefix into printk_parse_prefix printk: Straighten out log_flags into printk_info_flags string_helpers: Escape double quotes in escape_special printk/console: Check consistent sequence number when handling race in console_unlock()
2021-08-30Merge tag 'irq-core-2021-08-30' of ↵Linus Torvalds1-3/+25
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq updates from Thomas Gleixner: "Updates to the interrupt core and driver subsystems: Core changes: - The usual set of small fixes and improvements all over the place, but nothing stands out MSI changes: - Further consolidation of the PCI/MSI interrupt chip code - Make MSI sysfs code independent of PCI/MSI and expose the MSI interrupts of platform devices in the same way as PCI exposes them. Driver changes: - Support for ARM GICv3 EPPI partitions - Treewide conversion to generic_handle_domain_irq() for all chained interrupt controllers - Conversion to bitmap_zalloc() throughout the irq chip drivers - The usual set of small fixes and improvements" * tag 'irq-core-2021-08-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (57 commits) platform-msi: Add ABI to show msi_irqs of platform devices genirq/msi: Move MSI sysfs handling from PCI to MSI core genirq/cpuhotplug: Demote debug printk to KERN_DEBUG irqchip/qcom-pdc: Trim unused levels of the interrupt hierarchy irqdomain: Export irq_domain_disconnect_hierarchy() irqchip/gic-v3: Fix priority comparison when non-secure priorities are used irqchip/apple-aic: Fix irq_disable from within irq handlers pinctrl/rockchip: drop the gpio related codes gpio/rockchip: drop irq_gc_lock/irq_gc_unlock for irq set type gpio/rockchip: support next version gpio controller gpio/rockchip: use struct rockchip_gpio_regs for gpio controller gpio/rockchip: add driver for rockchip gpio dt-bindings: gpio: change items restriction of clock for rockchip,gpio-bank pinctrl/rockchip: add pinctrl device to gpio bank struct pinctrl/rockchip: separate struct rockchip_pin_bank to a head file pinctrl/rockchip: always enable clock for gpio controller genirq: Fix kernel doc indentation EDAC/altera: Convert to generic_handle_domain_irq() powerpc: Bulk conversion to generic_handle_domain_irq() nios2: Bulk conversion to generic_handle_domain_irq() ...
2021-08-28Documentation: Replace deprecated CPU-hotplug functions.Sebastian Andrzej Siewior1-1/+1
The functions get_online_cpus() and put_online_cpus() have been deprecated during the CPU hotplug rework. They map directly to cpus_read_lock() and cpus_read_unlock(). Update the documentation accordingly. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20210803141621.780504-2-bigeasy@linutronix.de
2021-08-12Documentation: Update irq_domain.rst with new lookup APIsMarc Zyngier1-3/+25
Catch up with the recent irqdomain updates, and document {generic_,}handle_domain_irq(), irq_resolve_mapping() as well as the deprecation of some of the older APIs. Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-07-26printk: Move the printk() kerneldoc comment to its new homeJonathan Corbet1-4/+1
Commit 337015573718 ("printk: Userspace format indexing support") turned printk() into a macro, but left the kerneldoc comment for it with the (now) _printk() function, resulting in this docs-build warning: kernel/printk/printk.c:1: warning: 'printk' not found Move the kerneldoc comment back next to the (now) macro it's meant to describe and have the docs build find it there. Fixes: 337015573718b161 ("printk: Userspace format indexing support") Signed-off-by: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/87o8aqt7qn.fsf@meer.lwn.net
2021-07-25docs: printk-formats: fix build warningIoana Ciornei1-0/+1
Add an empty line after the '::' starting the code block so that the following lines are properly interpreted. Without this, the following build warnings are visible. Documentation/core-api/printk-formats.rst:136: WARNING: Unexpected indentation. Documentation/core-api/printk-formats.rst:137: WARNING: Block quote ends without a blank line; unexpected unindent. Fixes: 9294523e3768 ("module: add printk formats to add module build ID to stacktraces") Signed-off-by: Ioana Ciornei <ioana.ciornei@nxp.com> Reviewed-by: Stephen Boyd <swboyd@chromium.org> Acked-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/20210722100356.635078-2-ciorneiioana@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-07-15docs/core-api: Modify document layoutYanteng Si1-14/+24
Modify the layout of the document and remove unnecessary symbols. Signed-off-by: Yanteng Si <siyanteng@loongson.cn> Reviewed-by: Wu XiangCheng <bobwxc@email.cn> Link: https://lore.kernel.org/r/f151bbc0d1ff6cf24611a698c76b90181f005f8d.1625798719.git.siyanteng@loongson.cn Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-07-08module: add printk formats to add module build ID to stacktracesStephen Boyd1-0/+11
Let's make kernel stacktraces easier to identify by including the build ID[1] of a module if the stacktrace is printing a symbol from a module. This makes it simpler for developers to locate a kernel module's full debuginfo for a particular stacktrace. Combined with scripts/decode_stracktrace.sh, a developer can download the matching debuginfo from a debuginfod[2] server and find the exact file and line number for the functions plus offsets in a stacktrace that match the module. This is especially useful for pstore crash debugging where the kernel crashes are recorded in something like console-ramoops and the recovery kernel/modules are different or the debuginfo doesn't exist on the device due to space concerns (the debuginfo can be too large for space limited devices). Originally, I put this on the %pS format, but that was quickly rejected given that %pS is used in other places such as ftrace where build IDs aren't meaningful. There was some discussions on the list to put every module build ID into the "Modules linked in:" section of the stacktrace message but that quickly becomes very hard to read once you have more than three or four modules linked in. It also provides too much information when we don't expect each module to be traversed in a stacktrace. Having the build ID for modules that aren't important just makes things messy. Splitting it to multiple lines for each module quickly explodes the number of lines printed in an oops too, possibly wrapping the warning off the console. And finally, trying to stash away each module used in a callstack to provide the ID of each symbol printed is cumbersome and would require changes to each architecture to stash away modules and return their build IDs once unwinding has completed. Instead, we opt for the simpler approach of introducing new printk formats '%pS[R]b' for "pointer symbolic backtrace with module build ID" and '%pBb' for "pointer backtrace with module build ID" and then updating the few places in the architecture layer where the stacktrace is printed to use this new format. Before: Call trace: lkdtm_WARNING+0x28/0x30 [lkdtm] direct_entry+0x16c/0x1b4 [lkdtm] full_proxy_write+0x74/0xa4 vfs_write+0xec/0x2e8 After: Call trace: lkdtm_WARNING+0x28/0x30 [lkdtm 6c2215028606bda50de823490723dc4bc5bf46f9] direct_entry+0x16c/0x1b4 [lkdtm 6c2215028606bda50de823490723dc4bc5bf46f9] full_proxy_write+0x74/0xa4 vfs_write+0xec/0x2e8 [akpm@linux-foundation.org: fix build with CONFIG_MODULES=n, tweak code layout] [rdunlap@infradead.org: fix build when CONFIG_MODULES is not set] Link: https://lkml.kernel.org/r/20210513171510.20328-1-rdunlap@infradead.org [akpm@linux-foundation.org: make kallsyms_lookup_buildid() static] [cuibixuan@huawei.com: fix build error when CONFIG_SYSFS is disabled] Link: https://lkml.kernel.org/r/20210525105049.34804-1-cuibixuan@huawei.com Link: https://lkml.kernel.org/r/20210511003845.2429846-6-swboyd@chromium.org Link: https://fedoraproject.org/wiki/Releases/FeatureBuildId [1] Link: https://sourceware.org/elfutils/Debuginfod.html [2] Signed-off-by: Stephen Boyd <swboyd@chromium.org> Signed-off-by: Bixuan Cui <cuibixuan@huawei.com> Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Jessica Yu <jeyu@kernel.org> Cc: Evan Green <evgreen@chromium.org> Cc: Hsin-Yi Wang <hsinyi@chromium.org> Cc: Petr Mladek <pmladek@suse.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Matthew Wilcox <willy@infradead.org> Cc: Baoquan He <bhe@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Dave Young <dyoung@redhat.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Cc: Sasha Levin <sashal@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-07-02Merge branch 'akpm' (patches from Andrew)Linus Torvalds1-5/+2
Merge more updates from Andrew Morton: "190 patches. Subsystems affected by this patch series: mm (hugetlb, userfaultfd, vmscan, kconfig, proc, z3fold, zbud, ras, mempolicy, memblock, migration, thp, nommu, kconfig, madvise, memory-hotplug, zswap, zsmalloc, zram, cleanups, kfence, and hmm), procfs, sysctl, misc, core-kernel, lib, lz4, checkpatch, init, kprobes, nilfs2, hfs, signals, exec, kcov, selftests, compress/decompress, and ipc" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (190 commits) ipc/util.c: use binary search for max_idx ipc/sem.c: use READ_ONCE()/WRITE_ONCE() for use_global_lock ipc: use kmalloc for msg_queue and shmid_kernel ipc sem: use kvmalloc for sem_undo allocation lib/decompressors: remove set but not used variabled 'level' selftests/vm/pkeys: exercise x86 XSAVE init state selftests/vm/pkeys: refill shadow register after implicit kernel write selftests/vm/pkeys: handle negative sys_pkey_alloc() return code selftests/vm/pkeys: fix alloc_random_pkey() to make it really, really random kcov: add __no_sanitize_coverage to fix noinstr for all architectures exec: remove checks in __register_bimfmt() x86: signal: don't do sas_ss_reset() until we are certain that sigframe won't be abandoned hfsplus: report create_date to kstat.btime hfsplus: remove unnecessary oom message nilfs2: remove redundant continue statement in a while-loop kprobes: remove duplicated strong free_insn_page in x86 and s390 init: print out unknown kernel parameters checkpatch: do not complain about positive return values starting with EPOLL checkpatch: improve the indented label test checkpatch: scripts/spdxcheck.py now requires python3 ...
2021-07-01kernel.h: split out kstrtox() and simple_strtox() to a separate headerAndy Shevchenko1-5/+2
kernel.h is being used as a dump for all kinds of stuff for a long time. Here is the attempt to start cleaning it up by splitting out kstrtox() and simple_strtox() helpers. At the same time convert users in header and lib folders to use new header. Though for time being include new header back to kernel.h to avoid twisted indirected includes for existing users. [andy.shevchenko@gmail.com: fix documentation references] Link: https://lkml.kernel.org/r/20210615220003.377901-1-andy.shevchenko@gmail.com Link: https://lkml.kernel.org/r/20210611185815.44103-1-andriy.shevchenko@linux.intel.com Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Cc: Francis Laniel <laniel_francis@privacyrequired.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Kars Mulder <kerneldev@karsmulder.nl> Cc: Trond Myklebust <trond.myklebust@hammerspace.com> Cc: Anna Schumaker <anna.schumaker@netapp.com> Cc: "J. Bruce Fields" <bfields@fieldses.org> Cc: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-06-29Merge tag 'irq-core-2021-06-29' of ↵Linus Torvalds1-1/+0
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq updates from Thomas Gleixner: "Updates for the interrupt subsystem: Core changes: - Cleanup and simplification of common code to invoke the low level interrupt flow handlers when this invocation requires irqdomain resolution. Add the necessary core infrastructure. - Provide a proper interface for modular PMU drivers to set the interrupt affinity. - Add a request flag which allows to exclude interrupts from spurious interrupt detection. Useful especially for IPI handlers which always return IRQ_HANDLED which turns the spurious interrupt detection into a pointless waste of CPU cycles. Driver changes: - Bulk convert interrupt chip drivers to the new irqdomain low level flow handler invocation mechanism. - Add device tree bindings for the Renesas R-Car M3-W+ SoC - Enable modular build of the Qualcomm PDC driver - The usual small fixes and improvements" * tag 'irq-core-2021-06-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (38 commits) dt-bindings: interrupt-controller: arm,gic-v3: Describe GICv3 optional properties irqchip: gic-pm: Remove redundant error log of clock bulk irqchip/sun4i: Remove unnecessary oom message irqchip/irq-imx-gpcv2: Remove unnecessary oom message irqchip/imgpdc: Remove unnecessary oom message irqchip/gic-v3-its: Remove unnecessary oom message irqchip/gic-v2m: Remove unnecessary oom message irqchip/exynos-combiner: Remove unnecessary oom message irqchip: Bulk conversion to generic_handle_domain_irq() genirq: Move non-irqdomain handle_domain_irq() handling into ARM's handle_IRQ() genirq: Add generic_handle_domain_irq() helper irqchip/nvic: Convert from handle_IRQ() to handle_domain_irq() irqdesc: Fix __handle_domain_irq() comment genirq: Use irq_resolve_mapping() to implement __handle_domain_irq() and co irqdomain: Introduce irq_resolve_mapping() irqdomain: Protect the linear revmap with RCU irqdomain: Cache irq_data instead of a virq number in the revmap irqdomain: Use struct_size() helper when allocating irqdomain irqdomain: Make normal and nomap irqdomains exclusive powerpc: Move the use of irq_domain_add_nomap() behind a config option ...