linux/drivers/dma-buf, branch v6.4

udmabuf: revert 'Add support for mapping hugepages (v4)'

2023-06-19T20:19:32Z

This effectively reverts commit 16c243e99d33 ("udmabuf: Add support for mapping hugepages (v4)"). Recently, Junxiao Chang found a BUG with page map counting as described here [1]. This issue pointed out that the udmabuf driver was making direct use of subpages of hugetlb pages. This is not a good idea, and no other mm code attempts such use. In addition to the mapcount issue, this also causes issues with hugetlb vmemmap optimization and page poisoning. For now, remove hugetlb support. If udmabuf wants to be used on hugetlb mappings, it should be changed to only use complete hugetlb pages. This will require different alignment and size requirements on the UDMABUF_CREATE API. [1] https://lore.kernel.org/linux-mm/20230512072036.1027784-1-junxiao.chang@intel.com/ Link: https://lkml.kernel.org/r/20230608204927.88711-1-mike.kravetz@oracle.com Fixes: 16c243e99d33 ("udmabuf: Add support for mapping hugepages (v4)") Signed-off-by: Mike Kravetz Acked-by: Greg Kroah-Hartman Acked-by: Vivek Kasireddy Acked-by: Gerd Hoffmann Cc: David Hildenbrand Cc: Dongwon Kim Cc: James Houghton Cc: Jerome Marchand Cc: Junxiao Chang Cc: Kirill A. Shutemov Cc: Michal Hocko Cc: Muchun Song Cc: Signed-off-by: Andrew Morton

Merge tag 'mm-stable-2023-04-27-15-30' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2023-04-28T02:42:02Z

Pull MM updates from Andrew Morton: - Nick Piggin's "shoot lazy tlbs" series, to improve the peformance of switching from a user process to a kernel thread. - More folio conversions from Kefeng Wang, Zhang Peng and Pankaj Raghav. - zsmalloc performance improvements from Sergey Senozhatsky. - Yue Zhao has found and fixed some data race issues around the alteration of memcg userspace tunables. - VFS rationalizations from Christoph Hellwig: - removal of most of the callers of write_one_page() - make __filemap_get_folio()'s return value more useful - Luis Chamberlain has changed tmpfs so it no longer requires swap backing. Use `mount -o noswap'. - Qi Zheng has made the slab shrinkers operate locklessly, providing some scalability benefits. - Keith Busch has improved dmapool's performance, making part of its operations O(1) rather than O(n). - Peter Xu adds the UFFD_FEATURE_WP_UNPOPULATED feature to userfaultd, permitting userspace to wr-protect anon memory unpopulated ptes. - Kirill Shutemov has changed MAX_ORDER's meaning to be inclusive rather than exclusive, and has fixed a bunch of errors which were caused by its unintuitive meaning. - Axel Rasmussen give userfaultfd the UFFDIO_CONTINUE_MODE_WP feature, which causes minor faults to install a write-protected pte. - Vlastimil Babka has done some maintenance work on vma_merge(): cleanups to the kernel code and improvements to our userspace test harness. - Cleanups to do_fault_around() by Lorenzo Stoakes. - Mike Rapoport has moved a lot of initialization code out of various mm/ files and into mm/mm_init.c. - Lorenzo Stoakes removd vmf_insert_mixed_prot(), which was added for DRM, but DRM doesn't use it any more. - Lorenzo has also coverted read_kcore() and vread() to use iterators and has thereby removed the use of bounce buffers in some cases. - Lorenzo has also contributed further cleanups of vma_merge(). - Chaitanya Prakash provides some fixes to the mmap selftesting code. - Matthew Wilcox changes xfs and afs so they no longer take sleeping locks in ->map_page(), a step towards RCUification of pagefaults. - Suren Baghdasaryan has improved mmap_lock scalability by switching to per-VMA locking. - Frederic Weisbecker has reworked the percpu cache draining so that it no longer causes latency glitches on cpu isolated workloads. - Mike Rapoport cleans up and corrects the ARCH_FORCE_MAX_ORDER Kconfig logic. - Liu Shixin has changed zswap's initialization so we no longer waste a chunk of memory if zswap is not being used. - Yosry Ahmed has improved the performance of memcg statistics flushing. - David Stevens has fixed several issues involving khugepaged, userfaultfd and shmem. - Christoph Hellwig has provided some cleanup work to zram's IO-related code paths. - David Hildenbrand has fixed up some issues in the selftest code's testing of our pte state changing. - Pankaj Raghav has made page_endio() unneeded and has removed it. - Peter Xu contributed some rationalizations of the userfaultfd selftests. - Yosry Ahmed has fixed an issue around memcg's page recalim accounting. - Chaitanya Prakash has fixed some arm-related issues in the selftests/mm code. - Longlong Xia has improved the way in which KSM handles hwpoisoned pages. - Peter Xu fixes a few issues with uffd-wp at fork() time. - Stefan Roesch has changed KSM so that it may now be used on a per-process and per-cgroup basis. * tag 'mm-stable-2023-04-27-15-30' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (369 commits) mm,unmap: avoid flushing TLB in batch if PTE is inaccessible shmem: restrict noswap option to initial user namespace mm/khugepaged: fix conflicting mods to collapse_file() sparse: remove unnecessary 0 values from rc mm: move 'mmap_min_addr' logic from callers into vm_unmapped_area() hugetlb: pte_alloc_huge() to replace huge pte_alloc_map() maple_tree: fix allocation in mas_sparse_area() mm: do not increment pgfault stats when page fault handler retries zsmalloc: allow only one active pool compaction context selftests/mm: add new selftests for KSM mm: add new KSM process and sysfs knobs mm: add new api to enable ksm per process mm: shrinkers: fix debugfs file permissions mm: don't check VMA write permissions if the PTE/PMD indicates write permissions migrate_pages_batch: fix statistics for longterm pin retry userfaultfd: use helper function range_in_vma() lib/show_mem.c: use for_each_populated_zone() simplify code mm: correct arg in reclaim_pages()/reclaim_clean_pages_from_list() fs/buffer: convert create_page_buffers to folio_create_buffers fs/buffer: add folio_create_empty_buffers helper ...

Merge tag 'modules-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux

2023-04-27T23:36:55Z

Pull module updates from Luis Chamberlain: "The summary of the changes for this pull requests is: - Song Liu's new struct module_memory replacement - Nick Alcock's MODULE_LICENSE() removal for non-modules - My cleanups and enhancements to reduce the areas where we vmalloc module memory for duplicates, and the respective debug code which proves the remaining vmalloc pressure comes from userspace. Most of the changes have been in linux-next for quite some time except the minor fixes I made to check if a module was already loaded prior to allocating the final module memory with vmalloc and the respective debug code it introduces to help clarify the issue. Although the functional change is small it is rather safe as it can only *help* reduce vmalloc space for duplicates and is confirmed to fix a bootup issue with over 400 CPUs with KASAN enabled. I don't expect stable kernels to pick up that fix as the cleanups would have also had to have been picked up. Folks on larger CPU systems with modules will want to just upgrade if vmalloc space has been an issue on bootup. Given the size of this request, here's some more elaborate details: The functional change change in this pull request is the very first patch from Song Liu which replaces the 'struct module_layout' with a new 'struct module_memory'. The old data structure tried to put together all types of supported module memory types in one data structure, the new one abstracts the differences in memory types in a module to allow each one to provide their own set of details. This paves the way in the future so we can deal with them in a cleaner way. If you look at changes they also provide a nice cleanup of how we handle these different memory areas in a module. This change has been in linux-next since before the merge window opened for v6.3 so to provide more than a full kernel cycle of testing. It's a good thing as quite a bit of fixes have been found for it. Jason Baron then made dynamic debug a first class citizen module user by using module notifier callbacks to allocate / remove module specific dynamic debug information. Nick Alcock has done quite a bit of work cross-tree to remove module license tags from things which cannot possibly be module at my request so to: a) help him with his longer term tooling goals which require a deterministic evaluation if a piece a symbol code could ever be part of a module or not. But quite recently it is has been made clear that tooling is not the only one that would benefit. Disambiguating symbols also helps efforts such as live patching, kprobes and BPF, but for other reasons and R&D on this area is active with no clear solution in sight. b) help us inch closer to the now generally accepted long term goal of automating all the MODULE_LICENSE() tags from SPDX license tags In so far as a) is concerned, although module license tags are a no-op for non-modules, tools which would want create a mapping of possible modules can only rely on the module license tag after the commit 8b41fc4454e ("kbuild: create modules.builtin without Makefile.modbuiltin or tristate.conf"). Nick has been working on this *for years* and AFAICT I was the only one to suggest two alternatives to this approach for tooling. The complexity in one of my suggested approaches lies in that we'd need a possible-obj-m and a could-be-module which would check if the object being built is part of any kconfig build which could ever lead to it being part of a module, and if so define a new define -DPOSSIBLE_MODULE [0]. A more obvious yet theoretical approach I've suggested would be to have a tristate in kconfig imply the same new -DPOSSIBLE_MODULE as well but that means getting kconfig symbol names mapping to modules always, and I don't think that's the case today. I am not aware of Nick or anyone exploring either of these options. Quite recently Josh Poimboeuf has pointed out that live patching, kprobes and BPF would benefit from resolving some part of the disambiguation as well but for other reasons. The function granularity KASLR (fgkaslr) patches were mentioned but Joe Lawrence has clarified this effort has been dropped with no clear solution in sight [1]. In the meantime removing module license tags from code which could never be modules is welcomed for both objectives mentioned above. Some developers have also welcomed these changes as it has helped clarify when a module was never possible and they forgot to clean this up, and so you'll see quite a bit of Nick's patches in other pull requests for this merge window. I just picked up the stragglers after rc3. LWN has good coverage on the motivation behind this work [2] and the typical cross-tree issues he ran into along the way. The only concrete blocker issue he ran into was that we should not remove the MODULE_LICENSE() tags from files which have no SPDX tags yet, even if they can never be modules. Nick ended up giving up on his efforts due to having to do this vetting and backlash he ran into from folks who really did *not understand* the core of the issue nor were providing any alternative / guidance. I've gone through his changes and dropped the patches which dropped the module license tags where an SPDX license tag was missing, it only consisted of 11 drivers. To see if a pull request deals with a file which lacks SPDX tags you can just use: ./scripts/spdxcheck.py -f \ $(git diff --name-only commid-id | xargs echo) You'll see a core module file in this pull request for the above, but that's not related to his changes. WE just need to add the SPDX license tag for the kernel/module/kmod.c file in the future but it demonstrates the effectiveness of the script. Most of Nick's changes were spread out through different trees, and I just picked up the slack after rc3 for the last kernel was out. Those changes have been in linux-next for over two weeks. The cleanups, debug code I added and final fix I added for modules were motivated by David Hildenbrand's report of boot failing on a systems with over 400 CPUs when KASAN was enabled due to running out of virtual memory space. Although the functional change only consists of 3 lines in the patch "module: avoid allocation if module is already present and ready", proving that this was the best we can do on the modules side took quite a bit of effort and new debug code. The initial cleanups I did on the modules side of things has been in linux-next since around rc3 of the last kernel, the actual final fix for and debug code however have only been in linux-next for about a week or so but I think it is worth getting that code in for this merge window as it does help fix / prove / evaluate the issues reported with larger number of CPUs. Userspace is not yet fixed as it is taking a bit of time for folks to understand the crux of the issue and find a proper resolution. Worst come to worst, I have a kludge-of-concept [3] of how to make kernel_read*() calls for modules unique / converge them, but I'm currently inclined to just see if userspace can fix this instead" Link: https://lore.kernel.org/all/Y/kXDqW+7d71C4wz@bombadil.infradead.org/ [0] Link: https://lkml.kernel.org/r/025f2151-ce7c-5630-9b90-98742c97ac65@redhat.com [1] Link: https://lwn.net/Articles/927569/ [2] Link: https://lkml.kernel.org/r/20230414052840.1994456-3-mcgrof@kernel.org [3] * tag 'modules-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux: (121 commits) module: add debugging auto-load duplicate module support module: stats: fix invalid_mod_bytes typo module: remove use of uninitialized variable len module: fix building stats for 32-bit targets module: stats: include uapi/linux/module.h module: avoid allocation if module is already present and ready module: add debug stats to help identify memory pressure module: extract patient module check into helper modules/kmod: replace implementation with a semaphore Change DEFINE_SEMAPHORE() to take a number argument module: fix kmemleak annotations for non init ELF sections module: Ignore L0 and rename is_arm_mapping_symbol() module: Move is_arm_mapping_symbol() to module_symbol.h module: Sync code of is_arm_mapping_symbol() scripts/gdb: use mem instead of core_layout to get the module address interconnect: remove module-related code interconnect: remove MODULE_LICENSE in non-modules zswap: remove MODULE_LICENSE in non-modules zpool: remove MODULE_LICENSE in non-modules x86/mm/dump_pagetables: remove MODULE_LICENSE in non-modules ...

Merge tag 'driver-core-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

2023-04-27T18:53:57Z

Pull driver core updates from Greg KH: "Here is the large set of driver core changes for 6.4-rc1. Once again, a busy development cycle, with lots of changes happening in the driver core in the quest to be able to move "struct bus" and "struct class" into read-only memory, a task now complete with these changes. This will make the future rust interactions with the driver core more "provably correct" as well as providing more obvious lifetime rules for all busses and classes in the kernel. The changes required for this did touch many individual classes and busses as many callbacks were changed to take const * parameters instead. All of these changes have been submitted to the various subsystem maintainers, giving them plenty of time to review, and most of them actually did so. Other than those changes, included in here are a small set of other things: - kobject logging improvements - cacheinfo improvements and updates - obligatory fw_devlink updates and fixes - documentation updates - device property cleanups and const * changes - firwmare loader dependency fixes. All of these have been in linux-next for a while with no reported problems" * tag 'driver-core-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (120 commits) device property: make device_property functions take const device * driver core: update comments in device_rename() driver core: Don't require dynamic_debug for initcall_debug probe timing firmware_loader: rework crypto dependencies firmware_loader: Strip off \n from customized path zram: fix up permission for the hot_add sysfs file cacheinfo: Add use_arch[|_cache]_info field/function arch_topology: Remove early cacheinfo error message if -ENOENT cacheinfo: Check cache properties are present in DT cacheinfo: Check sib_leaf in cache_leaves_are_shared() cacheinfo: Allow early level detection when DT/ACPI info is missing/broken cacheinfo: Add arm64 early level initializer implementation cacheinfo: Add arch specific early level initializer tty: make tty_class a static const structure driver core: class: remove struct class_interface * from callbacks driver core: class: mark the struct class in struct class_interface constant driver core: class: make class_register() take a const * driver core: class: mark class_release() as taking a const * driver core: remove incorrect comment for device_create* MIPS: vpe-cmp: remove module owner pointer from struct class usage. ...

udmabuf: remove MODULE_LICENSE in non-modules

2023-04-13T20:13:54Z

Since commit 8b41fc4454e ("kbuild: create modules.builtin without Makefile.modbuiltin or tristate.conf"), MODULE_LICENSE declarations are used to identify modules. As a consequence, uses of the macro in non-modules will cause modprobe to misidentify their containing object file as a module when it is not (false positives), and modprobe might succeed rather than failing with a suitable error message. So remove it in the files in this commit, none of which can be built as modules. Signed-off-by: Nick Alcock Suggested-by: Luis Chamberlain Cc: Luis Chamberlain Cc: linux-modules@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: Hitomi Hasegawa Cc: Gerd Hoffmann Cc: Sumit Semwal Cc: "Christian König" Cc: dri-devel@lists.freedesktop.org Cc: linux-media@vger.kernel.org Cc: linaro-mm-sig@lists.linaro.org Signed-off-by: Luis Chamberlain

dma-buf: heaps: remove MODULE_LICENSE in non-modules

2023-04-13T20:13:52Z

Since commit 8b41fc4454e ("kbuild: create modules.builtin without Makefile.modbuiltin or tristate.conf"), MODULE_LICENSE declarations are used to identify modules. As a consequence, uses of the macro in non-modules will cause modprobe to misidentify their containing object file as a module when it is not (false positives), and modprobe might succeed rather than failing with a suitable error message. So remove it in the files in this commit, none of which can be built as modules. Signed-off-by: Nick Alcock Suggested-by: Luis Chamberlain Cc: Luis Chamberlain Cc: linux-modules@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: Hitomi Hasegawa Cc: Sumit Semwal Cc: "Christian König" Cc: linux-media@vger.kernel.org Cc: dri-devel@lists.freedesktop.org Cc: linaro-mm-sig@lists.linaro.org Signed-off-by: Luis Chamberlain

Merge tag 'dma-fence-deadline' of https://gitlab.freedesktop.org/drm/msm into drm-next

2023-03-29T13:45:38Z

This series adds a deadline hint to fences, so realtime deadlines such as vblank can be communicated to the fence signaller for power/ frequency management decisions. This is partially inspired by a trick i915 does, but implemented via dma-fence for a couple of reasons: 1) To continue to be able to use the atomic helpers 2) To support cases where display and gpu are different drivers See https://patchwork.freedesktop.org/series/93035/ This does not yet add any UAPI, although this will be needed in a number of cases: 1) Workloads "ping-ponging" between CPU and GPU, where we don't want the GPU freq governor to interpret time stalled waiting for GPU as "idle" time 2) Cases where the compositor is waiting for fences to be signaled before issuing the atomic ioctl, for example to maintain 60fps cursor updates even when the GPU is not able to maintain that framerate. Signed-off-by: Daniel Vetter From: Rob Clark Link: https://patchwork.freedesktop.org/patch/msgid/CAF6AEGt5nDQpa6J86V1oFKPA30YcJzPhAVpmF7N1K1g2N3c=Zg@mail.gmail.com

dma-buf: system_heap: avoid reclaim for order 4

2023-03-28T23:20:12Z

Using order 4 pages would be helpful for IOMMUs mapping, but trying to get order 4 pages could spend quite much time in the page allocation. From the perspective of responsiveness, the deterministic memory allocation speed, I think, is quite important. The order 4 allocation with __GFP_RECLAIM may spend much time in reclaim and compation logic. __GFP_NORETRY also may affect. These cause unpredictable delay. To get reasonable allocation speed from dma-buf system heap, use HIGH_ORDER_GFP for order 4 to avoid reclaim. And let me remove meaningless __GFP_COMP for order 0. According to my tests, order 4 with MID_ORDER_GFP could get more number of order 4 pages but the elapsed times could be very slow. time order 8 order 4 order 0 584 usec 0 160 0 28,428 usec 0 160 0 100,701 usec 0 160 0 76,645 usec 0 160 0 25,522 usec 0 160 0 38,798 usec 0 160 0 89,012 usec 0 160 0 23,015 usec 0 160 0 73,360 usec 0 160 0 76,953 usec 0 160 0 31,492 usec 0 160 0 75,889 usec 0 160 0 84,551 usec 0 160 0 84,352 usec 0 160 0 57,103 usec 0 160 0 93,452 usec 0 160 0 If HIGH_ORDER_GFP is used for order 4, the number of order 4 could be decreased but the elapsed time results were quite stable and fast enough. time order 8 order 4 order 0 1,356 usec 0 155 80 1,901 usec 0 11 2384 1,912 usec 0 0 2560 1,911 usec 0 0 2560 1,884 usec 0 0 2560 1,577 usec 0 0 2560 1,366 usec 0 0 2560 1,711 usec 0 0 2560 1,635 usec 0 28 2112 544 usec 10 0 0 633 usec 2 128 0 848 usec 0 160 0 729 usec 0 160 0 1,000 usec 0 160 0 1,358 usec 0 160 0 2,638 usec 0 31 2064 Link: https://lkml.kernel.org/r/20230303050332.10138-1-jaewon31.kim@samsung.com Signed-off-by: Jaewon Kim Reviewed-by: John Stultz Cc: Daniel Vetter Cc: Johannes Weiner Cc: Michal Hocko Cc: Sumit Semwal Cc: T.J. Mercier Signed-off-by: Andrew Morton

dma-buf/dma-resv: Add a way to set fence deadline

2023-03-28T20:39:02Z

Add a way to set a deadline on remaining resv fences according to the requested usage. Signed-off-by: Rob Clark Reviewed-by: Christian König

dma-buf/fence-chain: Add fence deadline support

2023-03-28T20:38:52Z

Propagate the deadline to all the fences in the chain. v2: Use dma_fence_chain_contained [Tvrtko] Signed-off-by: Rob Clark Reviewed-by: Christian König