Changes in Kconfig

609fc8766d68da10697e1df0514d079d54bf48df - dma-buf: Always build with DMABUF_MOVE_NOTIFY

Sat, 24 Jan 2026 20:14:15 +0100

dma-buf: Always build with DMABUF_MOVE_NOTIFYDMABUF_MOVE_NOTIFY was introduced in 2018 and has been marked asexperimental and disabled by default ever since. Six years later,all new importers implement this callback.It is therefore reasonable to drop CONFIG_DMABUF_MOVE_NOTIFY andalways build DMABUF with support for it enabled.Suggested-by: Christian König Signed-off-by: Leon Romanovsky Reviewed-by: Christian König Link: https://lore.kernel.org/r/20260124-dmabuf-revoke-v5-3-f98fca917e96@nvidia.comSigned-off-by: Christian König List of files: /linux/drivers/dma-buf/Kconfig

ab4c3dcf9a71582503b4fb25aeab884c696cab25 - dma-buf: Remove DMA-BUF sysfs stats

Fri, 16 Jan 2026 20:05:12 +0100

dma-buf: Remove DMA-BUF sysfs statsCommit bdb8d06dfefd ("dmabuf: Add the capability to expose DMA-BUF statsin sysfs") added dmabuf statistics to sysfs in 2021 underCONFIG_DMABUF_SYSFS_STATS. After being used in production, performanceproblems were discovered leading to its deprecation in 2022 in commite0a9f1fe206a ("dma-buf: deprecate DMABUF_SYSFS_STATS"). Some of theproblems with this interface were discussed in my LPC 2025 talk. [1][2]Android was probably the last user of the interface, which has sincebeen migrated to use the dmabuf BPF iterator [3] to obtain the sameinformation more cheaply. As promised in that series, now that thelongterm stable 6.18 kernel has been released let's remove the sysfsdmabuf statistics from the kernel.[1] https://www.youtube.com/watch?v=D83qygudq9c[2] https://lpc.events/event/19/contributions/2118/[3] https://lore.kernel.org/all/20250522230429.941193-1-tjmercier@google.com/Signed-off-by: T.J. Mercier Reviewed-by: Christian König Signed-off-by: Sumit Semwal Link: https://patch.msgid.link/20260116190517.3268458-1-tjmercier@google.com List of files: /linux/drivers/dma-buf/Kconfig

646013f513f38a3e75a60fde31ae0e6154ce19a7 - dma-buf: enable DMABUF_DEBUG by default on DEBUG kernels

Thu, 04 Dec 2025 15:56:03 +0100

dma-buf: enable DMABUF_DEBUG by default on DEBUG kernelsThe overhead of enforcing the DMA-buf rules for importers is now so lowthat it safe to enable it by default on DEBUG kernels.This will hopefully result in fixing more issues in importers.Signed-off-by: Christian König Reviewed-by: Michael J. Ruhl Link: https://lore.kernel.org/r/20251205130604.1582-2-christian.koenig@amd.com List of files: /linux/drivers/dma-buf/Kconfig

ceb7b62eaaaacfcf87473bd2e99ac73a758620cb - Revert "udmabuf: fix vmap_udmabuf error page set"

Mon, 28 Apr 2025 09:38:29 +0200

Revert "udmabuf: fix vmap_udmabuf error page set"This reverts commit 18d7de823b7150344d242c3677e65d68c5271b04.We cannot use vmap_pfn() in vmap_udmabuf() as it would fail the pfn_valid()check in vmap_pfn_apply(). This is because vmap_pfn() is intended to beused for mapping non-struct-page memory such as PCIe BARs. Since, udmabufmostly works with pages/folios backed by shmem/hugetlbfs/THP, vmap_pfn()is not the right tool or API to invoke for implementing vmap.Signed-off-by: Huan Yang Suggested-by: Vivek Kasireddy Reported-by: Bingbu Cao Closes: https://lore.kernel.org/dri-devel/eb7e0137-3508-4287-98c4-816c5fd98e10@vivo.com/T/#mbda4f64a3532b32e061f4e8763bc8e307bea3ca8Acked-by: Vivek Kasireddy Signed-off-by: Vivek Kasireddy Link: https://lore.kernel.org/r/20250428073831.19942-2-link@vivo.com List of files: /linux/drivers/dma-buf/Kconfig

18d7de823b7150344d242c3677e65d68c5271b04 - udmabuf: fix vmap_udmabuf error page set

Wed, 18 Sep 2024 04:52:26 +0200

udmabuf: fix vmap_udmabuf error page setCurrently vmap_udmabuf set page's array by each folio.But, ubuf->folios is only contain's the folio's head page.That mean we repeatedly mapped the folio head page to the vmalloc area.Due to udmabuf can use hugetlb, if HVO enabled, tail page may not exist,so, we can't use page array to map, instead, use pfn array.By this, we removed page usage in udmabuf totally.Fixes: 5e72b2b41a21 ("udmabuf: convert udmabuf driver to use folios")Suggested-by: Vivek Kasireddy Signed-off-by: Huan Yang Acked-by: Vivek Kasireddy Signed-off-by: Vivek Kasireddy Link: https://patchwork.freedesktop.org/patch/msgid/20240918025238.2957823-4-link@vivo.com List of files: /linux/drivers/dma-buf/Kconfig

725553d202dda60dc17a142c80fd96bdf6ca43db - udmabuf: add CONFIG_MMU dependency

Mon, 24 Jun 2024 08:36:12 +0200

udmabuf: add CONFIG_MMU dependencyThere is no !CONFIG_MMU version of vmf_insert_pfn():arm-linux-gnueabi-ld: drivers/dma-buf/udmabuf.o: in function `udmabuf_vm_fault':udmabuf.c:(.text+0xaa): undefined reference to `vmf_insert_pfn'Link: https://lkml.kernel.org/r/20240624063952.1572359-5-vivek.kasireddy@intel.comSigned-off-by: Arnd Bergmann Acked-by: David Hildenbrand Acked-by: Vivek Kasireddy Cc: Christoph Hellwig Cc: Christoph Hellwig Cc: Daniel Vetter Cc: Dave Airlie Cc: Dongwon Kim Cc: Gerd Hoffmann Cc: Hugh Dickins Cc: Jason Gunthorpe Cc: Junxiao Chang Cc: Matthew Wilcox (Oracle) Cc: Mike Kravetz Cc: Oscar Salvador Cc: Peter Xu Cc: Shuah Khan Signed-off-by: Andrew Morton List of files: /linux/drivers/dma-buf/Kconfig

e0a9f1fe206a66c3507ff8b7da56f9d1d1dbb9c4 - dma-buf: deprecate DMABUF_SYSFS_STATS

Fri, 17 Jun 2022 10:35:25 +0200

dma-buf: deprecate DMABUF_SYSFS_STATSAdd a warning that this UAPI wasn't such a good idea and shouldn't beused by anybody.That should give us a better chance to remove it at some point andprevents others from running into the same issues.Signed-off-by: Christian König Reviewed-by: T.J. Mercier Link: https://patchwork.freedesktop.org/patch/msgid/20220617085702.4298-1-christian.koenig@amd.com List of files: /linux/drivers/dma-buf/Kconfig

87fd9ef47597b2fcee3264eb5f288410b9f376d5 - dma-buf: DMABUF_SYSFS_STATS should depend on DMA_SHARED_BUFFER

Thu, 02 Sep 2021 14:49:13 +0200

dma-buf: DMABUF_SYSFS_STATS should depend on DMA_SHARED_BUFFERDMA-BUF sysfs statistics are an option of DMA-BUF. It does not makemuch sense to bother the user with a question about DMA-BUF sysfsstatistics if DMA-BUF itself is not enabled. Worse, enabling thestatistics enables the feature.Fixes: bdb8d06dfefd666d ("dmabuf: Add the capability to expose DMA-BUF stats in sysfs")Signed-off-by: Geert Uytterhoeven Signed-off-by: Sumit Semwal Link: https://patchwork.freedesktop.org/patch/msgid/20210902124913.2698760-4-geert@linux-m68k.org List of files: /linux/drivers/dma-buf/Kconfig

cca62758ebdd71fcfb6d589d6487a7f26398d50d - dma-buf: DMABUF_DEBUG should depend on DMA_SHARED_BUFFER

Thu, 02 Sep 2021 14:49:12 +0200

dma-buf: DMABUF_DEBUG should depend on DMA_SHARED_BUFFERDMA-BUF debug checks are an option of DMA-BUF. Enabling DMABUF_DEBUGwithout DMA_SHARED_BUFFER does not have any impact, as drivers/dma-buf/is not entered during the build when DMA_SHARED_BUFFER is disabled.Fixes: 84335675f2223cbd ("dma-buf: Add debug option")Signed-off-by: Geert Uytterhoeven Signed-off-by: Sumit Semwal Link: https://patchwork.freedesktop.org/patch/msgid/20210902124913.2698760-3-geert@linux-m68k.org List of files: /linux/drivers/dma-buf/Kconfig

c4f3a3460a5daebc772d9263500e4099b11e7300 - dma-buf: DMABUF_MOVE_NOTIFY should depend on DMA_SHARED_BUFFER

Thu, 02 Sep 2021 14:49:11 +0200

dma-buf: DMABUF_MOVE_NOTIFY should depend on DMA_SHARED_BUFFERMove notify between drivers is an option of DMA-BUF. EnablingDMABUF_MOVE_NOTIFY without DMA_SHARED_BUFFER does not have any impact,as drivers/dma-buf/ is not entered during the build whenDMA_SHARED_BUFFER is disabled.Fixes: bb42df4662a44765 ("dma-buf: add dynamic DMA-buf handling v15")Signed-off-by: Geert Uytterhoeven Signed-off-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/msgid/20210902124913.2698760-2-geert@linux-m68k.org List of files: /linux/drivers/dma-buf/Kconfig

bdb8d06dfefd666d5981d884b535b04105869fcc - dmabuf: Add the capability to expose DMA-BUF stats in sysfs

Thu, 03 Jun 2021 23:47:51 +0200

dmabuf: Add the capability to expose DMA-BUF stats in sysfsOverview========The patch adds DMA-BUF statistics to /sys/kernel/dmabuf/buffers. Itallows statistics to be enabled for each DMA-BUF in sysfs by enablingthe config CONFIG_DMABUF_SYSFS_STATS.The following stats will be exposed by the interface:/sys/kernel/dmabuf/buffers//exporter_name/sys/kernel/dmabuf/buffers//size/sys/kernel/dmabuf/buffers//attachments//device/sys/kernel/dmabuf/buffers//attachments//map_counterThe inode_number is unique for each DMA-BUF and was added earlier [1]in order to allow userspace to track DMA-BUF usage across differentprocesses.Use Cases=========The interface provides a way to gather DMA-BUF per-buffer statisticsfrom production devices. These statistics will be used to derive DMA-BUFper-exporter stats and per-device usage stats for Android Bug reports.The corresponding userspace changes can be found at [2].Telemetry tools will also capture this information(along with othermemory metrics) periodically as well as on important events like aforeground app kill (which might have been triggered by Low MemoryKiller). It will also contribute to provide a snapshot of the systemmemory usage on other events such as OOM kills and Application NotResponding events.Background==========Currently, there are two existing interfaces that provide informationabout DMA-BUFs.1) /sys/kernel/debug/dma_buf/bufinfodebugfs is however unsuitable to be mounted in production systems andcannot be considered as an alternative to the sysfs interface beingproposed.2) proc//fdinfo/The proc//fdinfo/ files expose information about DMA-BUF fds.However, the existing procfs interfaces can only provide informationabout the buffers for which processes hold fds or have the buffersmmapped into their address space. Since the procfs interfaces alonecannot provide a full picture of all DMA-BUFs in the system, there isthe need for an alternate interface to provide this information onproduction systems.The patch contains the following major improvements over v1:1) Each attachment is represented by its own directory to allow creatinga symlink to the importing device and to also provide room for futureexpansion.2) The number of distinct mappings of each attachment is exposed in aseparate file.3) The per-buffer statistics are now in /sys/kernel/dmabuf/buffersinorder to make the interface expandable in future.All of the improvements above are based on suggestions/feedback fromDaniel Vetter and Christian König.A shell script that can be run on a classic Linux environment to readout the DMA-BUF statistics can be found at [3](suggested by JohnStultz).[1]: https://lore.kernel.org/patchwork/patch/1088791/[2]: https://android-review.googlesource.com/q/topic:%22dmabuf-sysfs%22+(status:open%20OR%20status:merged)[3]: https://android-review.googlesource.com/c/platform/system/memory/libmeminfo/+/1549734Reviewed-by: Greg Kroah-Hartman Signed-off-by: Hridya Valsaraju Reported-by: kernel test robot Signed-off-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/msgid/20210603214758.2955251-1-hridya@google.com List of files: /linux/drivers/dma-buf/Kconfig

84335675f2223cbd25d0de7d38ecc7d40b95bd4a - dma-buf: Add debug option

Fri, 15 Jan 2021 17:47:39 +0100

dma-buf: Add debug optionWe have too many people abusing the struct page they can get at butreally shouldn't in importers. Aside from that the backing page mightsimply not exist (for dynamic p2p mappings) looking at it and using ite.g. for mmap can also wreak the page handling of the exportercompletely. Importers really must go through the proper interface likedma_buf_mmap for everything.I'm semi-tempted to enforce this for dynamic importers since thosereally have no excuse at all to break the rules.Unfortuantely we can't store the right pointers somewhere safe to makesure we oops on something recognizable, so best is to just wranglethem a bit by flipping all the bits. At least on x86 kernel addresseshave all their high bits sets and the struct page array is fairly lowin the kernel mapping, so flipping all the bits gives us a very highpointer in userspace and hence excellent chances for an invaliddereference.v2: Add a note to the @map_dma_buf hook that exporters shouldn't dofancy caching tricks, which would blow up with this address scramblingtrick here (Chris)Enable by default when CONFIG_DMA_API_DEBUG is enabled.v3: Only one copy of the mangle/unmangle code (Christian)v4: #ifdef, not #if (0day)v5: sg_table can also be an ERR_PTR (Chris, Christian)Reviewed-by: Chris Wilson Reviewed-by: Christian König Signed-off-by: Daniel Vetter Cc: Chris Wilson Cc: Sumit Semwal Cc: "Christian König" Cc: David Stevens Cc: linux-media@vger.kernel.orgCc: linaro-mm-sig@lists.linaro.orgLink: https://patchwork.freedesktop.org/patch/msgid/20210115164739.3958206-1-daniel.vetter@ffwll.ch List of files: /linux/drivers/dma-buf/Kconfig

a7f7f6248d9740d710fd6bd190293fe5e16410ac - treewide: replace '---help---' in Kconfig files with 'help'

Sat, 13 Jun 2020 18:50:22 +0200

treewide: replace '---help---' in Kconfig files with 'help'Since commit 84af7a6194e4 ("checkpatch: kconfig: prefer 'help' over'---help---'"), the number of '---help---' has been graduallydecreasing, but there are still more than 2400 instances.This commit finishes the conversion. While I touched the lines,I also fixed the indentation.There are a variety of indentation styles found. a) 4 spaces + '---help---' b) 7 spaces + '---help---' c) 8 spaces + '---help---' d) 1 space + 1 tab + '---help---' e) 1 tab + '---help---' (correct indentation) f) 1 tab + 1 space + '---help---' g) 1 tab + 2 spaces + '---help---'In order to convert all of them to 1 tab + 'help', I ran thefollowing commend: $ find . -name 'Kconfig*' | xargs sed -i 's/^[[:space:]]*---help---/\thelp/'Signed-off-by: Masahiro Yamada List of files: /linux/drivers/dma-buf/Kconfig

518110cd0dedd7685ca365f464dd62c21c0a99e4 - dma-buf: Improve CONFIG_DMABUF_MOVE_NOTIFY help text

Tue, 24 Mar 2020 13:54:42 +0100

dma-buf: Improve CONFIG_DMABUF_MOVE_NOTIFY help textImprove the help text for the CONFIG_DMABUF_MOVE_NOTIFY symbol by: 1. Removing duplicated single quotes, 2. Adding a missing subject, 3. Fixing a misspelling of "yet", 4. Wrapping long lines.Fixes: bb42df4662a44765 ("dma-buf: add dynamic DMA-buf handling v15")Reviewed-by: Christian König Signed-off-by: Geert Uytterhoeven Signed-off-by: Alex Deucher Link: https://patchwork.freedesktop.org/patch/msgid/20200324125442.21983-1-geert+renesas@glider.be List of files: /linux/drivers/dma-buf/Kconfig

bb42df4662a4476531147c3d9caa1940f7ad36bb - dma-buf: add dynamic DMA-buf handling v15

Tue, 03 Jul 2018 16:42:26 +0200

dma-buf: add dynamic DMA-buf handling v15On the exporter side we add optional explicit pinning callbacks. Which arecalled when the importer doesn't implement dynamic handling, move notificationor need the DMA-buf locked in place for its use case.On the importer side we add an optional move_notify callback. This callback isused by the exporter to inform the importers that their mappings should bedestroyed as soon as possible.This allows the exporter to provide the mappings without the need to pinthe backing store.v2: don't try to invalidate mappings when the callback is NULL, lock the reservation obj while using the attachments, add helper to set the callbackv3: move flag for invalidation support into the DMA-buf, use new attach_info structure to set the callbackv4: use importer_priv field instead of mangling exporter priv.v5: drop invalidation_supported flagv6: squash together with pin/unpin changesv7: pin/unpin takes an attachment nowv8: nuke dma_buf_attachment_(map|unmap)_locked, everything is now handled backward compatiblev9: always cache when export/importer don't agree on dynamic handlingv10: minimal style cleanupv11: drop automatically re-entry avoidancev12: rename callback to move_notifyv13: add might_lock in appropriate placesv14: rebase on separated locking changev15: add EXPERIMENTAL flag, some more code commentsSigned-off-by: Christian König Reviewed-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/353993/?series=73646&rev=1 List of files: /linux/drivers/dma-buf/Kconfig

3e8a3844fefbaad911c596f02dd48c39188ffa81 - dma-buf: Fix a typo in Kconfig

Sun, 16 Feb 2020 12:47:08 +0100

dma-buf: Fix a typo in KconfigA 'h' ismissing in' syncronization'Signed-off-by: Christophe JAILLET Signed-off-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/msgid/20200216114708.20583-1-christophe.jaillet@wanadoo.fr List of files: /linux/drivers/dma-buf/Kconfig

efa04fefebbd724ffda7f49e42d057a7217c45b0 - dma-buf: heaps: Add system heap to dmabuf heaps

Tue, 03 Dec 2019 18:26:39 +0100

dma-buf: heaps: Add system heap to dmabuf heapsThis patch adds system heap to the dma-buf heaps framework.This allows applications to get a page-allocator backed dma-buffor non-contiguous memory.This code is an evolution of the Android ION implementation, sothanks to its original authors and maintainters: Rebecca Schultz Zavin, Colin Cross, Laura Abbott, and others!Cc: Laura Abbott Cc: Benjamin Gaignard Cc: Sumit Semwal Cc: Liam Mark Cc: Pratik Patel Cc: Brian Starkey Cc: Vincent Donnefort Cc: Sudipto Paul Cc: Andrew F. Davis Cc: Christoph Hellwig Cc: Chenbo Feng Cc: Alistair Strachan Cc: Hridya Valsaraju Cc: Sandeep Patil Cc: Hillf Danton Cc: Dave Airlie Cc: dri-devel@lists.freedesktop.orgReviewed-by: Benjamin Gaignard Reviewed-by: Brian Starkey Acked-by: Sandeep Patil Acked-by: Laura Abbott Tested-by: Ayan Kumar Halder Signed-off-by: John Stultz Signed-off-by: Sumit Semwal Link: https://patchwork.freedesktop.org/patch/msgid/20191203172641.66642-4-john.stultz@linaro.org List of files: /linux/drivers/dma-buf/Kconfig

c02a81fba74fe3488ad6b08bfb5a1329005418f8 - dma-buf: Add dma-buf heaps framework

Tue, 03 Dec 2019 18:26:37 +0100

dma-buf: Add dma-buf heaps frameworkThis framework allows a unified userspace interface for dma-bufexporters, allowing userland to allocate specific types of memoryfor use in dma-buf sharing.Each heap is given its own device node, which a user can allocatea dma-buf fd from using the DMA_HEAP_IOC_ALLOC.This code is an evoluiton of the Android ION implementation,and a big thanks is due to its authors/maintainers over timefor their effort: Rebecca Schultz Zavin, Colin Cross, Benjamin Gaignard, Laura Abbott, and many other contributors!Cc: Laura Abbott Cc: Benjamin Gaignard Cc: Sumit Semwal Cc: Liam Mark Cc: Pratik Patel Cc: Brian Starkey Cc: Vincent Donnefort Cc: Sudipto Paul Cc: Andrew F. Davis Cc: Christoph Hellwig Cc: Chenbo Feng Cc: Alistair Strachan Cc: Hridya Valsaraju Cc: Sandeep Patil Cc: Hillf Danton Cc: Dave Airlie Cc: dri-devel@lists.freedesktop.orgReviewed-by: Brian Starkey Acked-by: Sandeep Patil Signed-off-by: Andrew F. Davis Signed-off-by: John Stultz Signed-off-by: Sumit Semwal Link: https://patchwork.freedesktop.org/patch/msgid/20191203172641.66642-2-john.stultz@linaro.org List of files: /linux/drivers/dma-buf/Kconfig

fae7d7d5f374eadbb0b5dd31b39162e7176e9c3d - Revert "dma-buf: Add dma-buf heaps framework"

Wed, 30 Oct 2019 21:29:54 +0100

Revert "dma-buf: Add dma-buf heaps framework"This reverts commit a69b0e855d3fd278ff6f09a23e1edf929538e304.This patchset doesn't meet the UAPI requirements set out in [1] for the DRMsubsystem. Once the userspace component is reviewed and ready for mergewe can try again.[1]- https://01.org/linuxgraphics/gfx-docs/drm/gpu/drm-uapi.html#open-source-userspace-requirementsFixes: a69b0e855d3f ("dma-buf: Add dma-buf heaps framework")Cc: Laura Abbott Cc: Benjamin Gaignard Cc: Sumit Semwal Cc: Liam Mark Cc: Pratik Patel Cc: Brian Starkey Cc: Vincent Donnefort Cc: Sudipto Paul Cc: Andrew F. Davis Cc: Christoph Hellwig Cc: Chenbo Feng Cc: Alistair Strachan Cc: Hridya Valsaraju Cc: Hillf Danton Cc: dri-devel@lists.freedesktop.orgCc: Brian Starkey Cc: John Stultz Cc: Mauro Carvalho Chehab Cc: "David S. Miller" Cc: Greg Kroah-Hartman Cc: Rob Herring Cc: Jonathan Cameron Cc: "Paul E. McKenney" Cc: Sean Paul Cc: "Andrew F. Davis" Cc: linux-media@vger.kernel.orgCc: linaro-mm-sig@lists.linaro.orgAcked-by: David Airlie Signed-off-by: Sean Paul Link: https://patchwork.freedesktop.org/patch/msgid/20191030203003.101156-6-sean@poorly.run List of files: /linux/drivers/dma-buf/Kconfig

d59c5e025081a4c1f4528010524a37ddc5a986be - Revert "dma-buf: heaps: Add system heap to dmabuf heaps"

Wed, 30 Oct 2019 21:29:52 +0100

Revert "dma-buf: heaps: Add system heap to dmabuf heaps"This reverts commit 47a32f9c12266d450b92089148c6039591bd9909.This patchset doesn't meet the UAPI requirements set out in [1] for the DRMsubsystem. Once the userspace component is reviewed and ready for mergewe can try again.[1]- https://01.org/linuxgraphics/gfx-docs/drm/gpu/drm-uapi.html#open-source-userspace-requirementsFixes: 47a32f9c1226 ("dma-buf: heaps: Add system heap to dmabuf heaps")Cc: Laura Abbott Cc: Benjamin Gaignard Cc: Sumit Semwal Cc: Liam Mark Cc: Pratik Patel Cc: Brian Starkey Cc: Vincent Donnefort Cc: Sudipto Paul Cc: Andrew F. Davis Cc: Christoph Hellwig Cc: Chenbo Feng Cc: Alistair Strachan Cc: Hridya Valsaraju Cc: Hillf Danton Cc: dri-devel@lists.freedesktop.orgCc: Brian Starkey Cc: John Stultz Cc: "Andrew F. Davis" Cc: linux-media@vger.kernel.orgCc: linaro-mm-sig@lists.linaro.orgAcked-by: David Airlie Signed-off-by: Sean Paul Link: https://patchwork.freedesktop.org/patch/msgid/20191030203003.101156-4-sean@poorly.run List of files: /linux/drivers/dma-buf/Kconfig