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2024-01-18Merge tag 'dma-mapping-6.8-2024-01-18' of ↵Linus Torvalds
git://git.infradead.org/users/hch/dma-mapping Pull dma-mapping fixes from Christoph Hellwig: - fix kerneldoc warnings (Randy Dunlap) - better bounds checking in swiotlb (ZhangPeng) * tag 'dma-mapping-6.8-2024-01-18' of git://git.infradead.org/users/hch/dma-mapping: dma-debug: fix kernel-doc warnings swiotlb: check alloc_size before the allocation of a new memory pool
2024-01-15dma-debug: fix kernel-doc warningsRandy Dunlap
Update the kernel-doc comments to catch up with the code changes and fix the kernel-doc warnings: debug.c:83: warning: Excess struct member 'stacktrace' description in 'dma_debug_entry' debug.c:83: warning: Function parameter or struct member 'stack_len' not described in 'dma_debug_entry' debug.c:83: warning: Function parameter or struct member 'stack_entries' not described in 'dma_debug_entry' Fixes: 746017ed8d4d ("dma/debug: Simplify stracktrace retrieval") Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: Christoph Hellwig <hch@lst.de> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Robin Murphy <robin.murphy@arm.com> Cc: iommu@lists.linux.dev Signed-off-by: Christoph Hellwig <hch@lst.de>
2024-01-04dma-debug: make dma_debug_add_bus take a const pointerGreg Kroah-Hartman
The driver core now can handle a const struct bus_type pointer, and the dma_debug_add_bus() call just passes on the pointer give to it to the driver core, so make this pointer const as well to allow everyone to use read-only struct bus_type pointers going forward. Cc: Christoph Hellwig <hch@lst.de> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Robin Murphy <robin.murphy@arm.com> Cc: <iommu@lists.linux.dev> Reviewed-by: Robin Murphy <robin.murphy@arm.com> Link: https://lore.kernel.org/r/2023121941-dejected-nugget-681e@gregkh Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-10-23dma-debug: Fix a typo in a debugging eye-catcherChuck Lever
Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2023-08-30dma-debug: don't call __dma_entry_alloc_check_leak() under free_entries_lockSergey Senozhatsky
__dma_entry_alloc_check_leak() calls into printk -> serial console output (qcom geni) and grabs port->lock under free_entries_lock spin lock, which is a reverse locking dependency chain as qcom_geni IRQ handler can call into dma-debug code and grab free_entries_lock under port->lock. Move __dma_entry_alloc_check_leak() call out of free_entries_lock scope so that we don't acquire serial console's port->lock under it. Trimmed-down lockdep splat: The existing dependency chain (in reverse order) is: -> #2 (free_entries_lock){-.-.}-{2:2}: _raw_spin_lock_irqsave+0x60/0x80 dma_entry_alloc+0x38/0x110 debug_dma_map_page+0x60/0xf8 dma_map_page_attrs+0x1e0/0x230 dma_map_single_attrs.constprop.0+0x6c/0xc8 geni_se_rx_dma_prep+0x40/0xcc qcom_geni_serial_isr+0x310/0x510 __handle_irq_event_percpu+0x110/0x244 handle_irq_event_percpu+0x20/0x54 handle_irq_event+0x50/0x88 handle_fasteoi_irq+0xa4/0xcc handle_irq_desc+0x28/0x40 generic_handle_domain_irq+0x24/0x30 gic_handle_irq+0xc4/0x148 do_interrupt_handler+0xa4/0xb0 el1_interrupt+0x34/0x64 el1h_64_irq_handler+0x18/0x24 el1h_64_irq+0x64/0x68 arch_local_irq_enable+0x4/0x8 ____do_softirq+0x18/0x24 ... -> #1 (&port_lock_key){-.-.}-{2:2}: _raw_spin_lock_irqsave+0x60/0x80 qcom_geni_serial_console_write+0x184/0x1dc console_flush_all+0x344/0x454 console_unlock+0x94/0xf0 vprintk_emit+0x238/0x24c vprintk_default+0x3c/0x48 vprintk+0xb4/0xbc _printk+0x68/0x90 register_console+0x230/0x38c uart_add_one_port+0x338/0x494 qcom_geni_serial_probe+0x390/0x424 platform_probe+0x70/0xc0 really_probe+0x148/0x280 __driver_probe_device+0xfc/0x114 driver_probe_device+0x44/0x100 __device_attach_driver+0x64/0xdc bus_for_each_drv+0xb0/0xd8 __device_attach+0xe4/0x140 device_initial_probe+0x1c/0x28 bus_probe_device+0x44/0xb0 device_add+0x538/0x668 of_device_add+0x44/0x50 of_platform_device_create_pdata+0x94/0xc8 of_platform_bus_create+0x270/0x304 of_platform_populate+0xac/0xc4 devm_of_platform_populate+0x60/0xac geni_se_probe+0x154/0x160 platform_probe+0x70/0xc0 ... -> #0 (console_owner){-...}-{0:0}: __lock_acquire+0xdf8/0x109c lock_acquire+0x234/0x284 console_flush_all+0x330/0x454 console_unlock+0x94/0xf0 vprintk_emit+0x238/0x24c vprintk_default+0x3c/0x48 vprintk+0xb4/0xbc _printk+0x68/0x90 dma_entry_alloc+0xb4/0x110 debug_dma_map_sg+0xdc/0x2f8 __dma_map_sg_attrs+0xac/0xe4 dma_map_sgtable+0x30/0x4c get_pages+0x1d4/0x1e4 [msm] msm_gem_pin_pages_locked+0x38/0xac [msm] msm_gem_pin_vma_locked+0x58/0x88 [msm] msm_ioctl_gem_submit+0xde4/0x13ac [msm] drm_ioctl_kernel+0xe0/0x15c drm_ioctl+0x2e8/0x3f4 vfs_ioctl+0x30/0x50 ... Chain exists of: console_owner --> &port_lock_key --> free_entries_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(free_entries_lock); lock(&port_lock_key); lock(free_entries_lock); lock(console_owner); *** DEADLOCK *** Call trace: dump_backtrace+0xb4/0xf0 show_stack+0x20/0x30 dump_stack_lvl+0x60/0x84 dump_stack+0x18/0x24 print_circular_bug+0x1cc/0x234 check_noncircular+0x78/0xac __lock_acquire+0xdf8/0x109c lock_acquire+0x234/0x284 console_flush_all+0x330/0x454 console_unlock+0x94/0xf0 vprintk_emit+0x238/0x24c vprintk_default+0x3c/0x48 vprintk+0xb4/0xbc _printk+0x68/0x90 dma_entry_alloc+0xb4/0x110 debug_dma_map_sg+0xdc/0x2f8 __dma_map_sg_attrs+0xac/0xe4 dma_map_sgtable+0x30/0x4c get_pages+0x1d4/0x1e4 [msm] msm_gem_pin_pages_locked+0x38/0xac [msm] msm_gem_pin_vma_locked+0x58/0x88 [msm] msm_ioctl_gem_submit+0xde4/0x13ac [msm] drm_ioctl_kernel+0xe0/0x15c drm_ioctl+0x2e8/0x3f4 vfs_ioctl+0x30/0x50 ... Reported-by: Rob Clark <robdclark@chromium.org> Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Acked-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2023-03-30dma-debug: Use %pa to format phys_addr_tGeert Uytterhoeven
On 32-bit without LPAE: kernel/dma/debug.c: In function ‘debug_dma_dump_mappings’: kernel/dma/debug.c:537:7: warning: format ‘%llx’ expects argument of type ‘long long unsigned int’, but argument 9 has type ‘phys_addr_t’ {aka ‘unsigned int’} [-Wformat=] kernel/dma/debug.c: In function ‘dump_show’: kernel/dma/debug.c:568:59: warning: format ‘%llx’ expects argument of type ‘long long unsigned int’, but argument 11 has type ‘phys_addr_t’ {aka ‘unsigned int’} [-Wformat=] Fixes: bd89d69a529fbef3 ("dma-debug: add cacheline to user/kernel space dump messages") Reported-by: kernel test robot <lkp@intel.com> Link: https://lore.kernel.org/r/202303160548.ReyuTsGD-lkp@intel.com Reported-by: noreply@ellerman.id.au Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Christoph Hellwig <hch@lst.de>
2023-03-28dma-debug: add cacheline to user/kernel space dump messagesDesnes Nunes
Having the cacheline also printed on the debug_dma_dump_mappings() and dump_show() is useful for debugging. Furthermore, this also standardizes the messages shown on both dump functions. Signed-off-by: Desnes Nunes <desnesn@redhat.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2023-03-28dma-debug: small dma_debug_entry's comment and variable name updatesDesnes Nunes
Small update on dma_debug_entry's struct commentary and also standardize the usage of 'dma_addr' variable name from debug_dma_map_page() on debug_dma_unmap_page(), and similarly on debug_dma_free_coherent() Signed-off-by: Desnes Nunes <desnesn@redhat.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2022-09-07dma-debug: improve search for partial syncsRobin Murphy
When bucket_find_contains() tries to find the original entry for a partial sync, it manages to constrain its search in a way that is both too restrictive and not restrictive enough. A driver which only uses single mappings rather than scatterlists might not set max_seg_size, but could still technically perform a partial sync at an offset of more than 64KB into a sufficiently large mapping, so we could stop searching too early before reaching a legitimate entry. Conversely, if no valid entry is present and max_range is large enough, we can pointlessly search buckets that we've already searched, or that represent an impossible wrapping around the bottom of the address space. At worst, the (legitimate) case of max_seg_size == UINT_MAX can make the loop infinite. Replace the fragile and frankly hard-to-follow "range" logic with a simple counted loop for the number of possible hash buckets below the given address. Reported-by: Yunfei Wang <yf.wang@mediatek.com> Signed-off-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2022-06-02dma-debug: make things less spammy under memory pressureRob Clark
Limit the error msg to avoid flooding the console. If you have a lot of threads hitting this at once, they could have already gotten passed the dma_debug_disabled() check before they get to the point of allocation failure, resulting in quite a lot of this error message spamming the log. Use pr_err_once() to limit that. Signed-off-by: Rob Clark <robdclark@chromium.org> Signed-off-by: Christoph Hellwig <hch@lst.de>
2022-05-11dma-debug: change allocation mode from GFP_NOWAIT to GFP_ATIOMICMikulas Patocka
We observed the error "cacheline tracking ENOMEM, dma-debug disabled" during a light system load (copying some files). The reason for this error is that the dma_active_cacheline radix tree uses GFP_NOWAIT allocation - so it can't access the emergency memory reserves and it fails as soon as anybody reaches the watermark. This patch changes GFP_NOWAIT to GFP_ATOMIC, so that it can access the emergency memory reserves. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2022-03-03dma-debug: fix return value of __setup handlersRandy Dunlap
When valid kernel command line parameters dma_debug=off dma_debug_entries=100 are used, they are reported as Unknown parameters and added to init's environment strings, polluting it. Unknown kernel command line parameters "BOOT_IMAGE=/boot/bzImage-517rc5 dma_debug=off dma_debug_entries=100", will be passed to user space. and Run /sbin/init as init process with arguments: /sbin/init with environment: HOME=/ TERM=linux BOOT_IMAGE=/boot/bzImage-517rc5 dma_debug=off dma_debug_entries=100 Return 1 from these __setup handlers to indicate that the command line option has been handled. Fixes: 59d3daafa1726 ("dma-debug: add kernel command line parameters") Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Reported-by: Igor Zhbanov <i.zhbanov@omprussia.ru> Link: lore.kernel.org/r/64644a2f-4a20-bab3-1e15-3b2cdd0defe3@omprussia.ru Cc: Joerg Roedel <joro@8bytes.org> Cc: Christoph Hellwig <hch@lst.de> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: iommu@lists.linux-foundation.org Cc: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2021-10-18dma-debug: teach add_dma_entry() about DMA_ATTR_SKIP_CPU_SYNCHamza Mahfooz
Mapping something twice should be possible as long as, DMA_ATTR_SKIP_CPU_SYNC is passed to the strictly speaking second relevant mapping operation (that attempts to map the same thing). So, don't issue a warning if the specified condition is met in add_dma_entry(). Signed-off-by: Hamza Mahfooz <someguy@effective-light.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2021-10-11dma-debug: fix sg checks in debug_dma_map_sg()Gerald Schaefer
The following warning occurred sporadically on s390: DMA-API: nvme 0006:00:00.0: device driver maps memory from kernel text or rodata [addr=0000000048cc5e2f] [len=131072] WARNING: CPU: 4 PID: 825 at kernel/dma/debug.c:1083 check_for_illegal_area+0xa8/0x138 It is a false-positive warning, due to broken logic in debug_dma_map_sg(). check_for_illegal_area() checks for overlay of sg elements with kernel text or rodata. It is called with sg_dma_len(s) instead of s->length as parameter. After the call to ->map_sg(), sg_dma_len() will contain the length of possibly combined sg elements in the DMA address space, and not the individual sg element length, which would be s->length. The check will then use the physical start address of an sg element, and add the DMA length for the overlap check, which could result in the false warning, because the DMA length can be larger than the actual single sg element length. In addition, the call to check_for_illegal_area() happens in the iteration over mapped_ents, which will not include all individual sg elements if any of them were combined in ->map_sg(). Fix this by using s->length instead of sg_dma_len(s). Also put the call to check_for_illegal_area() in a separate loop, iterating over all the individual sg elements ("nents" instead of "mapped_ents"). While at it, as suggested by Robin Murphy, also move check_for_stack() inside the new loop, as it is similarly concerned with validating the individual sg elements. Link: https://lore.kernel.org/lkml/20210705185252.4074653-1-gerald.schaefer@linux.ibm.com Fixes: 884d05970bfb ("dma-debug: use sg_dma_len accessor") Signed-off-by: Gerald Schaefer <gerald.schaefer@linux.ibm.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2021-09-13dma-debug: prevent an error message from causing runtime problemsHamza Mahfooz
For some drivers, that use the DMA API. This error message can be reached several millions of times per second, causing spam to the kernel's printk buffer and bringing the CPU usage up to 100% (so, it should be rate limited). However, since there is at least one driver that is in the mainline and suffers from the error condition, it is more useful to err_printk() here instead of just rate limiting the error message (in hopes that it will make it easier for other drivers that suffer from this issue to be spotted). Link: https://lkml.kernel.org/r/fd67fbac-64bf-f0ea-01e1-5938ccfab9d0@arm.com Reported-by: Jeremy Linton <jeremy.linton@arm.com> Signed-off-by: Hamza Mahfooz <someguy@effective-light.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2021-08-09dma-debug: fix debugfs initialization orderAnthony Iliopoulos
Due to link order, dma_debug_init is called before debugfs has a chance to initialize (via debugfs_init which also happens in the core initcall stage), so the directories for dma-debug are never created. Decouple dma_debug_fs_init from dma_debug_init and defer its init until core_initcall_sync (after debugfs has been initialized) while letting dma-debug initialization occur as soon as possible to catch any early mappings, as suggested in [1]. [1] https://lore.kernel.org/linux-iommu/YIgGa6yF%2Fadg8OSN@kroah.com/ Fixes: 15b28bbcd567 ("dma-debug: move initialization to common code") Signed-off-by: Anthony Iliopoulos <ailiop@suse.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2021-08-09dma-debug: use memory_intersects() directlyKefeng Wang
There is already a memory_intersects() helper in sections.h, use memory_intersects() directly instead of private overlap(). Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2021-06-22dma-debug: report -EEXIST errors in add_dma_entryHamza Mahfooz
Since, overlapping mappings are not supported by the DMA API we should report an error if active_cacheline_insert returns -EEXIST. Suggested-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Hamza Mahfooz <someguy@effective-light.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-10-06dma-mapping: move dma-debug.h to kernel/dma/Christoph Hellwig
Most of dma-debug.h is not required by anything outside of kernel/dma. Move the four declarations needed by dma-mappin.h or dma-ops providers into dma-mapping.h and dma-map-ops.h, and move the remainder of the file to kernel/dma/debug.h. Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-09-21dma-debug: convert comma to semicolonXu Wang
Replace a comma between expression statements by a semicolon. Signed-off-by: Xu Wang <vulab@iscas.ac.cn> Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-09-11dma-debug: remove most exportsChristoph Hellwig
Now that the main dma mapping entry points are out of line most of the symbols in dma-debug.c can only be called from built-in code. Remove the unused exports. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Robin Murphy <robin.murphy@arm.com>
2020-08-14dma-debug: remove debug_dma_assert_idle() functionLinus Torvalds
This remoes the code from the COW path to call debug_dma_assert_idle(), which was added many years ago. Google shows that it hasn't caught anything in the 6+ years we've had it apart from a false positive, and Hugh just noticed how it had a very unfortunate spinlock serialization in the COW path. He fixed that issue the previous commit (a85ffd59bd36: "dma-debug: fix debug_dma_assert_idle(), use rcu_read_lock()"), but let's see if anybody even notices when we remove this function entirely. NOTE! We keep the dma tracking infrastructure that was added by the commit that introduced it. Partly to make it easier to resurrect this debug code if we ever deside to, and partly because that tracking by pfn and offset looks quite reasonable. The problem with this debug code was simply that it was expensive and didn't seem worth it, not that it was wrong per se. Acked-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-14dma-debug: fix debug_dma_assert_idle(), use rcu_read_lock()Hugh Dickins
Since commit 2a9127fcf229 ("mm: rewrite wait_on_page_bit_common() logic") improved unlock_page(), it has become more noticeable how cow_user_page() in a kernel with CONFIG_DMA_API_DEBUG=y can create and suffer from heavy contention on DMA debug's radix_lock in debug_dma_assert_idle(). It is only doing a lookup: use rcu_read_lock() and rcu_read_unlock() instead; though that does require the static ents[] to be moved onstack... ...but, hold on, isn't that radix_tree_gang_lookup() and loop doing quite the wrong thing: searching CACHELINES_PER_PAGE entries for an exact match with the first cacheline of the page in question? radix_tree_gang_lookup() is the right tool for the job, but we need nothing more than to check the first entry it can find, reporting if that falls anywhere within the page. (Is RCU safe here? As safe as using the spinlock was. The entries are never freed, so don't need to be freed by RCU. They may be reused, and there is a faint chance of a race, with an offending entry reused while printing its error info; but the spinlock did not prevent that either, and I agree that it's not worth worrying about. ] [ Side noe: this patch is a clear improvement to the status quo, but the next patch will be removing this debug function entirely. But just in case we decide we want to resurrect the debugging code some day, I'm first applying this improvement patch so that it doesn't get lost - Linus ] Fixes: 3b7a6418c749 ("dma debug: account for cachelines and read-only mappings in overlap tracking") Signed-off-by: Hugh Dickins <hughd@google.com> Acked-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-04Merge tag 'docs-5.9' of git://git.lwn.net/linuxLinus Torvalds
Pull documentation updates from Jonathan Corbet: "It's been a busy cycle for documentation - hopefully the busiest for a while to come. Changes include: - Some new Chinese translations - Progress on the battle against double words words and non-HTTPS URLs - Some block-mq documentation - More RST conversions from Mauro. At this point, that task is essentially complete, so we shouldn't see this kind of churn again for a while. Unless we decide to switch to asciidoc or something...:) - Lots of typo fixes, warning fixes, and more" * tag 'docs-5.9' of git://git.lwn.net/linux: (195 commits) scripts/kernel-doc: optionally treat warnings as errors docs: ia64: correct typo mailmap: add entry for <alobakin@marvell.com> doc/zh_CN: add cpu-load Chinese version Documentation/admin-guide: tainted-kernels: fix spelling mistake MAINTAINERS: adjust kprobes.rst entry to new location devices.txt: document rfkill allocation PCI: correct flag name docs: filesystems: vfs: correct flag name docs: filesystems: vfs: correct sync_mode flag names docs: path-lookup: markup fixes for emphasis docs: path-lookup: more markup fixes docs: path-lookup: fix HTML entity mojibake CREDITS: Replace HTTP links with HTTPS ones docs: process: Add an example for creating a fixes tag doc/zh_CN: add Chinese translation prefer section doc/zh_CN: add clearing-warn-once Chinese version doc/zh_CN: add admin-guide index doc:it_IT: process: coding-style.rst: Correct __maybe_unused compiler label futex: MAINTAINERS: Re-add selftests directory ...
2020-08-04Merge tag 'dma-mapping-5.9' of git://git.infradead.org/users/hch/dma-mappingLinus Torvalds
Pull dma-mapping updates from Christoph Hellwig: - make support for dma_ops optional - move more code out of line - add generic support for a dma_ops bypass mode - misc cleanups * tag 'dma-mapping-5.9' of git://git.infradead.org/users/hch/dma-mapping: dma-contiguous: cleanup dma_alloc_contiguous dma-debug: use named initializers for dir2name powerpc: use the generic dma_ops_bypass mode dma-mapping: add a dma_ops_bypass flag to struct device dma-mapping: make support for dma ops optional dma-mapping: inline the fast path dma-direct calls dma-mapping: move the remaining DMA API calls out of line
2020-07-19dma-debug: use named initializers for dir2nameChristoph Hellwig
Make dir2name a little more readable and maintainable by using named initializers. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Robin Murphy <robin.murphy@arm.com>
2020-07-16treewide: Remove uninitialized_var() usageKees Cook
Using uninitialized_var() is dangerous as it papers over real bugs[1] (or can in the future), and suppresses unrelated compiler warnings (e.g. "unused variable"). If the compiler thinks it is uninitialized, either simply initialize the variable or make compiler changes. In preparation for removing[2] the[3] macro[4], remove all remaining needless uses with the following script: git grep '\buninitialized_var\b' | cut -d: -f1 | sort -u | \ xargs perl -pi -e \ 's/\buninitialized_var\(([^\)]+)\)/\1/g; s:\s*/\* (GCC be quiet|to make compiler happy) \*/$::g;' drivers/video/fbdev/riva/riva_hw.c was manually tweaked to avoid pathological white-space. No outstanding warnings were found building allmodconfig with GCC 9.3.0 for x86_64, i386, arm64, arm, powerpc, powerpc64le, s390x, mips, sparc64, alpha, and m68k. [1] https://lore.kernel.org/lkml/20200603174714.192027-1-glider@google.com/ [2] https://lore.kernel.org/lkml/CA+55aFw+Vbj0i=1TGqCR5vQkCzWJ0QxK6CernOU6eedsudAixw@mail.gmail.com/ [3] https://lore.kernel.org/lkml/CA+55aFwgbgqhbp1fkxvRKEpzyR5J8n1vKT1VZdz9knmPuXhOeg@mail.gmail.com/ [4] https://lore.kernel.org/lkml/CA+55aFz2500WfbKXAx8s67wrm9=yVJu65TpLgN_ybYNv0VEOKA@mail.gmail.com/ Reviewed-by: Leon Romanovsky <leonro@mellanox.com> # drivers/infiniband and mlx4/mlx5 Acked-by: Jason Gunthorpe <jgg@mellanox.com> # IB Acked-by: Kalle Valo <kvalo@codeaurora.org> # wireless drivers Reviewed-by: Chao Yu <yuchao0@huawei.com> # erofs Signed-off-by: Kees Cook <keescook@chromium.org>
2020-06-26docs: fix references for DMA*.txt filesMauro Carvalho Chehab
As we moved those files to core-api, fix references to point to their newer locations. Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Link: https://lore.kernel.org/r/37b2fd159fbc7655dbf33b3eb1215396a25f6344.1592895969.git.mchehab+huawei@kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-04-20dma-debug: make __dma_entry_alloc_check_leak() staticJason Yan
Fix the following sparse warning: kernel/dma/debug.c:659:6: warning: symbol '__dma_entry_alloc_check_leak' was not declared. Should it be static? Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: Jason Yan <yanaijie@huawei.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-04-08dma-debug: fix displaying of dma allocation typeGrygorii Strashko
The commit 2e05ea5cdc1a ("dma-mapping: implement dma_map_single_attrs using dma_map_page_attrs") removed "dma_debug_page" enum, but missed to update type2name string table. This causes incorrect displaying of dma allocation type. Fix it by removing "page" string from type2name string table and switch to use named initializers. Before (dma_alloc_coherent()): k3-ringacc 4b800000.ringacc: scather-gather idx 2208 P=d1140000 N=d114 D=d1140000 L=40 DMA_BIDIRECTIONAL dma map error check not applicable k3-ringacc 4b800000.ringacc: scather-gather idx 2216 P=d1150000 N=d115 D=d1150000 L=40 DMA_BIDIRECTIONAL dma map error check not applicable After: k3-ringacc 4b800000.ringacc: coherent idx 2208 P=d1140000 N=d114 D=d1140000 L=40 DMA_BIDIRECTIONAL dma map error check not applicable k3-ringacc 4b800000.ringacc: coherent idx 2216 P=d1150000 N=d115 D=d1150000 L=40 DMA_BIDIRECTIONAL dma map error check not applicable Fixes: 2e05ea5cdc1a ("dma-mapping: implement dma_map_single_attrs using dma_map_page_attrs") Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-11-28Merge branch 'master' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux; tag 'dma-mapping-5.5' of git://git.infradead.org/users/hch/dma-mapping Pull dma-mapping updates from Christoph Hellwig: - improve dma-debug scalability (Eric Dumazet) - tiny dma-debug cleanup (Dan Carpenter) - check for vmap memory in dma_map_single (Kees Cook) - check for dma_addr_t overflows in dma-direct when using DMA offsets (Nicolas Saenz Julienne) - switch the x86 sta2x11 SOC to use more generic DMA code (Nicolas Saenz Julienne) - fix arm-nommu dma-ranges handling (Vladimir Murzin) - use __initdata in CMA (Shyam Saini) - replace the bus dma mask with a limit (Nicolas Saenz Julienne) - merge the remapping helpers into the main dma-direct flow (me) - switch xtensa to the generic dma remap handling (me) - various cleanups around dma_capable (me) - remove unused dev arguments to various dma-noncoherent helpers (me) * 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux: * tag 'dma-mapping-5.5' of git://git.infradead.org/users/hch/dma-mapping: (22 commits) dma-mapping: treat dev->bus_dma_mask as a DMA limit dma-direct: exclude dma_direct_map_resource from the min_low_pfn check dma-direct: don't check swiotlb=force in dma_direct_map_resource dma-debug: clean up put_hash_bucket() powerpc: remove support for NULL dev in __phys_to_dma / __dma_to_phys dma-direct: avoid a forward declaration for phys_to_dma dma-direct: unify the dma_capable definitions dma-mapping: drop the dev argument to arch_sync_dma_for_* x86/PCI: sta2x11: use default DMA address translation dma-direct: check for overflows on 32 bit DMA addresses dma-debug: increase HASH_SIZE dma-debug: reorder struct dma_debug_entry fields xtensa: use the generic uncached segment support dma-mapping: merge the generic remapping helpers into dma-direct dma-direct: provide mmap and get_sgtable method overrides dma-direct: remove the dma_handle argument to __dma_direct_alloc_pages dma-direct: remove __dma_direct_free_pages usb: core: Remove redundant vmap checks kernel: dma-contiguous: mark CMA parameters __initdata/__initconst dma-debug: add a schedule point in debug_dma_dump_mappings() ...
2019-11-20dma-debug: clean up put_hash_bucket()Dan Carpenter
The put_hash_bucket() is a bit cleaner if it takes an unsigned long directly instead of a pointer to unsigned long. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-11-11dma-debug: increase HASH_SIZEEric Dumazet
With modern NIC, it is not unusual having about ~256,000 active dma mappings and a hash size of 1024 buckets is too small. Forcing full cache line per bucket does not seem useful, especially now that we have contention on free_entries_lock for allocations and freeing of entries. Better use the space to fit more buckets. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-11-11dma-debug: reorder struct dma_debug_entry fieldsEric Dumazet
Move all fields used during exact match lookups to the first cache line. This makes debug_dma_mapping_error() and friends about 50% faster. Since it removes two 32bit holes, force a cacheline alignment on struct dma_debug_entry. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-10-30dma-debug: add a schedule point in debug_dma_dump_mappings()Eric Dumazet
debug_dma_dump_mappings() can take a lot of cpu cycles : lpk43:/# time wc -l /sys/kernel/debug/dma-api/dump 163435 /sys/kernel/debug/dma-api/dump real 0m0.463s user 0m0.003s sys 0m0.459s Let's add a cond_resched() to avoid holding cpu for too long. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Corentin Labbe <clabbe@baylibre.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-10-18dma-debug: Use pr_warn instead of pr_warningKefeng Wang
As said in commit f2c2cbcc35d4 ("powerpc: Use pr_warn instead of pr_warning"), removing pr_warning so all logging messages use a consistent <prefix>_warn style. Let's do it. Link: http://lkml.kernel.org/r/20191018031850.48498-25-wangkefeng.wang@huawei.com To: linux-kernel@vger.kernel.org Cc: Christoph Hellwig <hch@lst.de> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-06-05treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 333Thomas Gleixner
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation inc 59 temple place suite 330 boston ma 02111 1307 usa extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 136 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190530000436.384967451@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-29dma/debug: Simplify stracktrace retrievalThomas Gleixner
Replace the indirection through struct stack_trace with an invocation of the storage array based interface. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: iommu@lists.linux-foundation.org Cc: Robin Murphy <robin.murphy@arm.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Alexander Potapenko <glider@google.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: linux-mm@kvack.org Cc: David Rientjes <rientjes@google.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: kasan-dev@googlegroups.com Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: Akinobu Mita <akinobu.mita@gmail.com> Cc: Johannes Thumshirn <jthumshirn@suse.de> Cc: David Sterba <dsterba@suse.com> Cc: Chris Mason <clm@fb.com> Cc: Josef Bacik <josef@toxicpanda.com> Cc: linux-btrfs@vger.kernel.org Cc: dm-devel@redhat.com Cc: Mike Snitzer <snitzer@redhat.com> Cc: Alasdair Kergon <agk@redhat.com> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: intel-gfx@lists.freedesktop.org Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Cc: dri-devel@lists.freedesktop.org Cc: David Airlie <airlied@linux.ie> Cc: Jani Nikula <jani.nikula@linux.intel.com> Cc: Rodrigo Vivi <rodrigo.vivi@intel.com> Cc: Tom Zanussi <tom.zanussi@linux.intel.com> Cc: Miroslav Benes <mbenes@suse.cz> Cc: linux-arch@vger.kernel.org Link: https://lkml.kernel.org/r/20190425094802.248658135@linutronix.de
2019-04-11dma-debug: only skip one stackframe entryScott Wood
With skip set to 1, I get a traceback like this: [ 106.867637] DMA-API: Mapped at: [ 106.870784] afu_dma_map_region+0x2cd/0x4f0 [dfl_afu] [ 106.875839] afu_ioctl+0x258/0x380 [dfl_afu] [ 106.880108] do_vfs_ioctl+0xa9/0x720 [ 106.883688] ksys_ioctl+0x60/0x90 [ 106.887007] __x64_sys_ioctl+0x16/0x20 With the previous value of 2, afu_dma_map_region was being omitted. I suspect that the code paths have simply changed since the value of 2 was chosen a decade ago, but it's also possible that it varies based on which mapping function was used, compiler inlining choices, etc. In any case, it's best to err on the side of skipping less. Signed-off-by: Scott Wood <swood@redhat.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-02-01dma-debug: add dumping facility via debugfsCorentin Labbe
While debugging a DMA mapping leak, I needed to access debug_dma_dump_mappings() but easily from user space. This patch adds a /sys/kernel/debug/dma-api/dump file which contain all current DMA mapping. Signed-off-by: Corentin Labbe <clabbe@baylibre.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-02-01dma: debug: no need to check return value of debugfs_create functionsGreg Kroah-Hartman
When calling debugfs functions, there is no need to ever check the return value. The function can work or not, but the code logic should never do something different based on this. Also delete the variables for the file dentries for the debugfs entries as they are never used at all once they are created. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Robin Murphy <robin.murphy@arm.com> [hch: moved dma_debug_dent to function scope and renamed it] Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-01-04dma-mapping: remove a few unused exportsChristoph Hellwig
Now that the slow path DMA API calls are implemented out of line a few helpers only used by them don't need to be exported anymore. Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-01-04dma-mapping: implement dma_map_single_attrs using dma_map_page_attrsChristoph Hellwig
And also switch the way we implement the unmap side around to stay consistent. This ensures dma-debug works again because it records which function we used for mapping to ensure it is also used for unmapping, and also reduces further code duplication. Last but not least this also officially allows calling dma_sync_single_* for mappings created using dma_map_page, which is perfectly fine given that the sync calls only take a dma_addr_t, but not a virtual address or struct page. Fixes: 7f0fee242e ("dma-mapping: merge dma_unmap_page_attrs and dma_unmap_single_attrs") Signed-off-by: Christoph Hellwig <hch@lst.de> Tested-by: LABBE Corentin <clabbe.montjoie@gmail.com>
2018-12-13dma-mapping: simplify the dma_sync_single_range_for_{cpu,device} implementationChristoph Hellwig
We can just call the regular calls after adding offset the the address instead of reimplementing them. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Jesper Dangaard Brouer <brouer@redhat.com> Tested-by: Jesper Dangaard Brouer <brouer@redhat.com> Tested-by: Tony Luck <tony.luck@intel.com>
2018-12-11dma-debug: Batch dma_debug_entry allocationRobin Murphy
DMA debug entries are one of those things which aren't that useful individually - we will always want some larger quantity of them - and which we don't really need to manage the exact number of - we only care about having 'enough'. In that regard, the current behaviour of creating them one-by-one leads to a lot of unwarranted function call overhead and memory wasted on alignment padding. Now that we don't have to worry about freeing anything via dma_debug_resize_entries(), we can optimise the allocation behaviour by grabbing whole pages at once, which will save considerably on the aforementioned overheads, and probably offer a little more cache/TLB locality benefit for traversing the lists under normal operation. This should also give even less reason for an architecture-level override of the preallocation size, so make the definition unconditional - if there is still any desire to change the compile-time value for some platforms it would be better off as a Kconfig option anyway. Since freeing a whole page of entries at once becomes enough of a challenge that it's not really worth complicating dma_debug_init(), we may as well tweak the preallocation behaviour such that as long as we manage to allocate *some* pages, we can leave debugging enabled on a best-effort basis rather than otherwise wasting them. Signed-off-by: Robin Murphy <robin.murphy@arm.com> Tested-by: Qian Cai <cai@lca.pw> Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-12-11dma/debug: Remove dma_debug_resize_entries()Robin Murphy
With the only caller now gone, we can clean up this part of dma-debug's exposed internals and make way to tweak the allocation behaviour. Signed-off-by: Robin Murphy <robin.murphy@arm.com> Tested-by: Qian Cai <cai@lca.pw> Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-12-11dma-debug: Make leak-like behaviour apparentRobin Murphy
Now that we can dynamically allocate DMA debug entries to cope with drivers maintaining excessively large numbers of live mappings, a driver which *does* actually have a bug leaking mappings (and is not unloaded) will no longer trigger the "DMA-API: debugging out of memory - disabling" message until it gets to actual kernel OOM conditions, which means it could go unnoticed for a while. To that end, let's inform the user each time the pool has grown to a multiple of its initial size, which should make it apparent that they either have a leak or might want to increase the preallocation size. Signed-off-by: Robin Murphy <robin.murphy@arm.com> Tested-by: Qian Cai <cai@lca.pw> Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-12-11dma-debug: Dynamically expand the dma_debug_entry poolRobin Murphy
Certain drivers such as large multi-queue network adapters can use pools of mapped DMA buffers larger than the default dma_debug_entry pool of 65536 entries, with the result that merely probing such a device can cause DMA debug to disable itself during boot unless explicitly given an appropriate "dma_debug_entries=..." option. Developers trying to debug some other driver on such a system may not be immediately aware of this, and at worst it can hide bugs if they fail to realise that dma-debug has already disabled itself unexpectedly by the time their code of interest gets to run. Even once they do realise, it can be a bit of a pain to emprirically determine a suitable number of preallocated entries to configure, short of massively over-allocating. There's really no need for such a static limit, though, since we can quite easily expand the pool at runtime in those rare cases that the preallocated entries are insufficient, which is arguably the least surprising and most useful behaviour. To that end, refactor the prealloc_memory() logic a little bit to generalise it for runtime reallocations as well. Signed-off-by: Robin Murphy <robin.murphy@arm.com> Tested-by: Qian Cai <cai@lca.pw> Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-12-11dma-debug: Use pr_fmt()Robin Murphy
Use pr_fmt() to generate the "DMA-API: " prefix consistently. This results in it being added to a couple of pr_*() messages which were missing it before, and for the err_printk() calls moves it to the actual start of the message instead of somewhere in the middle. Signed-off-by: Robin Murphy <robin.murphy@arm.com> Tested-by: Qian Cai <cai@lca.pw> Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-12-11dma-debug: Expose nr_total_entries in debugfsRobin Murphy
Expose nr_total_entries in debugfs, so that {num,min}_free_entries become even more meaningful to users interested in current/maximum utilisation. This becomes even more relevant once nr_total_entries may change at runtime beyond just the existing AMD GART debug code. Suggested-by: John Garry <john.garry@huawei.com> Signed-off-by: Robin Murphy <robin.murphy@arm.com> Tested-by: Qian Cai <cai@lca.pw> Signed-off-by: Christoph Hellwig <hch@lst.de>