kernel/linux.git/include/linux, branch v5.8.17

dmaengine: dw: Add DMA-channels mask cell support

2020-10-29T09:08:29+00:00

[ Upstream commit e8ee6c8cb61b676f1a2d6b942329e98224bd8ee9 ] DW DMA IP-core provides a way to synthesize the DMA controller with channels having different parameters like maximum burst-length, multi-block support, maximum data width, etc. Those parameters both explicitly and implicitly affect the channels performance. Since DMA slave devices might be very demanding to the DMA performance, let's provide a functionality for the slaves to be assigned with DW DMA channels, which performance according to the platform engineer fulfill their requirements. After this patch is applied it can be done by passing the mask of suitable DMA-channels either directly in the dw_dma_slave structure instance or as a fifth cell of the DMA DT-property. If mask is zero or not provided, then there is no limitation on the channels allocation. For instance Baikal-T1 SoC is equipped with a DW DMAC engine, which first two channels are synthesized with max burst length of 16, while the rest of the channels have been created with max-burst-len=4. It would seem that the first two channels must be faster than the others and should be more preferable for the time-critical DMA slave devices. In practice it turned out that the situation is quite the opposite. The channels with max-burst-len=4 demonstrated a better performance than the channels with max-burst-len=16 even when they both had been initialized with the same settings. The performance drop of the first two DMA-channels made them unsuitable for the DW APB SSI slave device. No matter what settings they are configured with, full-duplex SPI transfers occasionally experience the Rx FIFO overflow. It means that the DMA-engine doesn't keep up with incoming data pace even though the SPI-bus is enabled with speed of 25MHz while the DW DMA controller is clocked with 50MHz signal. There is no such problem has been noticed for the channels synthesized with max-burst-len=4. Signed-off-by: Serge Semin Link: https://lore.kernel.org/r/20200731200826.9292-6-Sergey.Semin@baikalelectronics.ru Signed-off-by: Vinod Koul Signed-off-by: Sasha Levin

bpf: Limit caller's stack depth 256 for subprogs with tailcalls

2020-10-29T09:08:24+00:00

[ Upstream commit 7f6e4312e15a5c370e84eaa685879b6bdcc717e4 ] Protect against potential stack overflow that might happen when bpf2bpf calls get combined with tailcalls. Limit the caller's stack depth for such case down to 256 so that the worst case scenario would result in 8k stack size (32 which is tailcall limit * 256 = 8k). Suggested-by: Alexei Starovoitov Signed-off-by: Maciej Fijalkowski Signed-off-by: Alexei Starovoitov Signed-off-by: Sasha Levin

soc: mediatek: cmdq: add clear option in cmdq_pkt_wfe api

2020-10-29T09:08:15+00:00

[ Upstream commit 23c22299cd290409c6b78f57c42b64f8dfb6dd92 ] Add clear parameter to let client decide if event should be clear to 0 after GCE receive it. Signed-off-by: Dennis YC Hsieh Acked-by: Chun-Kuang Hu Link: https://lore.kernel.org/r/1594136714-11650-9-git-send-email-dennis-yc.hsieh@mediatek.com [mb: fix commit message] Signed-off-by: Matthias Brugger Signed-off-by: Sasha Levin

PCI/IOV: Mark VFs as not implementing PCI_COMMAND_MEMORY

2020-10-29T09:08:05+00:00

[ Upstream commit 12856e7acde4702b7c3238c15fcba86ff6aa507f ] For VFs, the Memory Space Enable bit in the Command Register is hard-wired to 0. Add a new bit to signify devices where the Command Register Memory Space Enable bit does not control the device's response to MMIO accesses. Fixes: abafbc551fdd ("vfio-pci: Invalidate mmaps and block MMIO access on disabled memory") Signed-off-by: Matthew Rosato Acked-by: Bjorn Helgaas Signed-off-by: Alex Williamson Signed-off-by: Sasha Levin

mm/page_owner: change split_page_owner to take a count

2020-10-29T09:08:03+00:00

[ Upstream commit 8fb156c9ee2db94f7127c930c89917634a1a9f56 ] The implementation of split_page_owner() prefers a count rather than the old order of the page. When we support a variable size THP, we won't have the order at this point, but we will have the number of pages. So change the interface to what the caller and callee would prefer. Signed-off-by: Matthew Wilcox (Oracle) Signed-off-by: Andrew Morton Reviewed-by: SeongJae Park Acked-by: Kirill A. Shutemov Cc: Huang Ying Link: https://lkml.kernel.org/r/20200908195539.25896-4-willy@infradead.org Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

overflow: Include header file with SIZE_MAX declaration

2020-10-29T09:08:00+00:00

[ Upstream commit a4947e84f23474803b62a2759b5808147e4e15f9 ] The various array_size functions use SIZE_MAX define, but missed limits.h causes to failure to compile code that needs overflow.h. In file included from drivers/infiniband/core/uverbs_std_types_device.c:6: ./include/linux/overflow.h: In function 'array_size': ./include/linux/overflow.h:258:10: error: 'SIZE_MAX' undeclared (first use in this function) 258 | return SIZE_MAX; | ^~~~~~~~ Fixes: 610b15c50e86 ("overflow.h: Add allocation size calculation helpers") Link: https://lore.kernel.org/r/20200913102928.134985-1-leon@kernel.org Signed-off-by: Leon Romanovsky Signed-off-by: Jason Gunthorpe Signed-off-by: Sasha Levin

mm, oom_adj: don't loop through tasks in __set_oom_adj when not necessary

2020-10-29T09:07:50+00:00

[ Upstream commit 67197a4f28d28d0b073ab0427b03cb2ee5382578 ] Currently __set_oom_adj loops through all processes in the system to keep oom_score_adj and oom_score_adj_min in sync between processes sharing their mm. This is done for any task with more that one mm_users, which includes processes with multiple threads (sharing mm and signals). However for such processes the loop is unnecessary because their signal structure is shared as well. Android updates oom_score_adj whenever a tasks changes its role (background/foreground/...) or binds to/unbinds from a service, making it more/less important. Such operation can happen frequently. We noticed that updates to oom_score_adj became more expensive and after further investigation found out that the patch mentioned in "Fixes" introduced a regression. Using Pixel 4 with a typical Android workload, write time to oom_score_adj increased from ~3.57us to ~362us. Moreover this regression linearly depends on the number of multi-threaded processes running on the system. Mark the mm with a new MMF_MULTIPROCESS flag bit when task is created with (CLONE_VM && !CLONE_THREAD && !CLONE_VFORK). Change __set_oom_adj to use MMF_MULTIPROCESS instead of mm_users to decide whether oom_score_adj update should be synchronized between multiple processes. To prevent races between clone() and __set_oom_adj(), when oom_score_adj of the process being cloned might be modified from userspace, we use oom_adj_mutex. Its scope is changed to global. The combination of (CLONE_VM && !CLONE_THREAD) is rarely used except for the case of vfork(). To prevent performance regressions of vfork(), we skip taking oom_adj_mutex and setting MMF_MULTIPROCESS when CLONE_VFORK is specified. Clearing the MMF_MULTIPROCESS flag (when the last process sharing the mm exits) is left out of this patch to keep it simple and because it is believed that this threading model is rare. Should there ever be a need for optimizing that case as well, it can be done by hooking into the exit path, likely following the mm_update_next_owner pattern. With the combination of (CLONE_VM && !CLONE_THREAD && !CLONE_VFORK) being quite rare, the regression is gone after the change is applied. [surenb@google.com: v3] Link: https://lkml.kernel.org/r/20200902012558.2335613-1-surenb@google.com Fixes: 44a70adec910 ("mm, oom_adj: make sure processes sharing mm have same view of oom_score_adj") Reported-by: Tim Murray Suggested-by: Michal Hocko Signed-off-by: Suren Baghdasaryan Signed-off-by: Andrew Morton Acked-by: Christian Brauner Acked-by: Michal Hocko Acked-by: Oleg Nesterov Cc: Ingo Molnar Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Eugene Syromiatnikov Cc: Christian Kellner Cc: Adrian Reber Cc: Shakeel Butt Cc: Aleksa Sarai Cc: Alexey Dobriyan Cc: "Eric W. Biederman" Cc: Alexey Gladkov Cc: Michel Lespinasse Cc: Daniel Jordan Cc: Andrei Vagin Cc: Bernd Edlinger Cc: John Johansen Cc: Yafang Shao Link: https://lkml.kernel.org/r/20200824153036.3201505-1-surenb@google.com Debugged-by: Minchan Kim Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

mm: khugepaged: recalculate min_free_kbytes after memory hotplug as expected by khugepaged

2020-10-14T09:55:59+00:00

commit 4aab2be0983031a05cb4a19696c9da5749523426 upstream. When memory is hotplug added or removed the min_free_kbytes should be recalculated based on what is expected by khugepaged. Currently after hotplug, min_free_kbytes will be set to a lower default and higher default set when THP enabled is lost. This change restores min_free_kbytes as expected for THP consumers. [vijayb@linux.microsoft.com: v5] Link: https://lkml.kernel.org/r/1601398153-5517-1-git-send-email-vijayb@linux.microsoft.com Fixes: f000565adb77 ("thp: set recommended min free kbytes") Signed-off-by: Vijay Balakrishna Signed-off-by: Andrew Morton Reviewed-by: Pavel Tatashin Acked-by: Michal Hocko Cc: Allen Pais Cc: Andrea Arcangeli Cc: "Kirill A. Shutemov" Cc: Oleg Nesterov Cc: Song Liu Cc: Link: https://lkml.kernel.org/r/1600305709-2319-2-git-send-email-vijayb@linux.microsoft.com Link: https://lkml.kernel.org/r/1600204258-13683-1-git-send-email-vijayb@linux.microsoft.com Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

mm: validate inode in mapping_set_error()

2020-10-14T09:55:59+00:00

commit 8b7b2eb131d3476062ffd34358785b44be25172f upstream. The swap address_space doesn't have host. Thus, it makes kernel crash once swap write meets error. Fix it. Fixes: 735e4ae5ba28 ("vfs: track per-sb writeback errors and report them to syncfs") Signed-off-by: Minchan Kim Signed-off-by: Andrew Morton Acked-by: Jeff Layton Cc: Jan Kara Cc: Andres Freund Cc: Matthew Wilcox Cc: Al Viro Cc: Christoph Hellwig Cc: Dave Chinner Cc: David Howells Cc: Link: https://lkml.kernel.org/r/20201010000650.750063-1-minchan@kernel.org Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

net/mlx5: Avoid possible free of command entry while timeout comp handler

2020-10-14T09:55:56+00:00

[ Upstream commit 50b2412b7e7862c5af0cbf4b10d93bc5c712d021 ] Upon command completion timeout, driver simulates a forced command completion. In a rare case where real interrupt for that command arrives simultaneously, it might release the command entry while the forced handler might still access it. Fix that by adding an entry refcount, to track current amount of allowed handlers. Command entry to be released only when this refcount is decremented to zero. Command refcount is always initialized to one. For callback commands, command completion handler is the symmetric flow to decrement it. For non-callback commands, it is wait_func(). Before ringing the doorbell, increment the refcount for the real completion handler. Once the real completion handler is called, it will decrement it. For callback commands, once the delayed work is scheduled, increment the refcount. Upon callback command completion handler, we will try to cancel the timeout callback. In case of success, we need to decrement the callback refcount as it will never run. In addition, gather the entry index free and the entry free into a one flow for all command types release. Fixes: e126ba97dba9 ("mlx5: Add driver for Mellanox Connect-IB adapters") Signed-off-by: Eran Ben Elisha Reviewed-by: Moshe Shemesh Signed-off-by: Saeed Mahameed Signed-off-by: Sasha Levin