kernel/linux.git/include/linux, branch v4.5.4

mm: memcontrol: let v2 cgroups follow changes in system swappiness

2016-05-11T09:21:31+00:00

commit 4550c4e157ca3da929593bb6c64080a59141af35 upstream. Cgroup2 currently doesn't have a per-cgroup swappiness setting. We might want to add one later - that's a different discussion - but until we do, the cgroups should always follow the system setting. Otherwise it will be unchangeably set to whatever the ancestor inherited from the system setting at the time of cgroup creation. Signed-off-by: Johannes Weiner Acked-by: Michal Hocko Acked-by: Vladimir Davydov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

Minimal fix-up of bad hashing behavior of hash_64()

2016-05-11T09:21:31+00:00

commit 689de1d6ca95b3b5bd8ee446863bf81a4883ea25 upstream. This is a fairly minimal fixup to the horribly bad behavior of hash_64() with certain input patterns. In particular, because the multiplicative value used for the 64-bit hash was intentionally bit-sparse (so that the multiply could be done with shifts and adds on architectures without hardware multipliers), some bits did not get spread out very much. In particular, certain fairly common bit ranges in the input (roughly bits 12-20: commonly with the most information in them when you hash things like byte offsets in files or memory that have block factors that mean that the low bits are often zero) would not necessarily show up much in the result. There's a bigger patch-series brewing to fix up things more completely, but this is the fairly minimal fix for the 64-bit hashing problem. It simply picks a much better constant multiplier, spreading the bits out a lot better. NOTE! For 32-bit architectures, the bad old hash_64() remains the same for now, since 64-bit multiplies are expensive. The bigger hashing cleanup will replace the 32-bit case with something better. The new constants were picked by George Spelvin who wrote that bigger cleanup series. I just picked out the constants and part of the comment from that series. Cc: George Spelvin Cc: Thomas Gleixner Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

clk-divider: make sure read-only dividers do not write to their register

2016-05-11T09:21:28+00:00

commit 50359819794b4a16ae35051cd80f2dab025f6019 upstream. Commit e6d5e7d90be9 ("clk-divider: Fix READ_ONLY when divider > 1") removed the special ops struct for read-only clocks and instead opted to handle them inside the regular ops. On the rk3368 this results in breakage as aclkm now gets set a value. While it is the same divider value, the A53 core still doesn't like it, which can result in the cpu ending up in a hang. The reason being that "ACLKENMasserts one clock cycle before the rising edge of ACLKM" and the clock should only be touched when STANDBYWFIL2 is asserted. To fix this, reintroduce the read-only ops but do include the round_rate callback. That way no writes that may be unsafe are done to the divider register in any case. The Rockchip use of the clk_divider_ops is adapted to this split again, as is the nxp, lpc18xx-ccu driver that was included since the original commit. On lpc18xx-ccu the divider seems to always be read-only so only uses the new ops now. Fixes: e6d5e7d90be9 ("clk-divider: Fix READ_ONLY when divider > 1") Reported-by: Zhang Qing Signed-off-by: Heiko Stuebner Signed-off-by: Stephen Boyd Signed-off-by: Greg Kroah-Hartman

dmaengine: mmp-pdma: add number of requestors

2016-05-04T21:49:16+00:00

commit c283e41ef32442f41e7180f9bb1c5aedf9255bfe upstream. The DMA chip has a fixed number of requestor lines used for flow control. This number is platform dependent. The pxa_dma dma driver will use this value to activate or not the flow control. There won't be any impact on mmp_pdma driver. Signed-off-by: Robert Jarzmik Signed-off-by: Greg Kroah-Hartman

numa: fix /proc//numa_maps for THP

2016-05-04T21:49:10+00:00

commit 28093f9f34cedeaea0f481c58446d9dac6dd620f upstream. In gather_pte_stats() a THP pmd is cast into a pte, which is wrong because the layouts may differ depending on the architecture. On s390 this will lead to inaccurate numa_maps accounting in /proc because of misguided pte_present() and pte_dirty() checks on the fake pte. On other architectures pte_present() and pte_dirty() may work by chance, but there may be an issue with direct-access (dax) mappings w/o underlying struct pages when HAVE_PTE_SPECIAL is set and THP is available. In vm_normal_page() the fake pte will be checked with pte_special() and because there is no "special" bit in a pmd, this will always return false and the VM_PFNMAP | VM_MIXEDMAP checking will be skipped. On dax mappings w/o struct pages, an invalid struct page pointer would then be returned that can crash the kernel. This patch fixes the numa_maps THP handling by introducing new "_pmd" variants of the can_gather_numa_stats() and vm_normal_page() functions. Signed-off-by: Gerald Schaefer Cc: Naoya Horiguchi Cc: "Kirill A . Shutemov" Cc: Konstantin Khlebnikov Cc: Michal Hocko Cc: Vlastimil Babka Cc: Jerome Marchand Cc: Johannes Weiner Cc: Dave Hansen Cc: Mel Gorman Cc: Dan Williams Cc: Martin Schwidefsky Cc: Heiko Carstens Cc: Michael Holzheu Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

mm: exclude HugeTLB pages from THP page_mapped() logic

2016-05-04T21:49:09+00:00

commit 66ee95d16a7f1b7b4f1dd74a2d81c6e19dc29a14 upstream. HugeTLB pages cannot be split, so we use the compound_mapcount to track rmaps. Currently page_mapped() will check the compound_mapcount, but will also go through the constituent pages of a THP compound page and query the individual _mapcount's too. Unfortunately, page_mapped() does not distinguish between HugeTLB and THP compound pages and assumes that a compound page always needs to have HPAGE_PMD_NR pages querying. For most cases when dealing with HugeTLB this is just inefficient, but for scenarios where the HugeTLB page size is less than the pmd block size (e.g. when using contiguous bit on ARM) this can lead to crashes. This patch adjusts the page_mapped function such that we skip the unnecessary THP reference checks for HugeTLB pages. Fixes: e1534ae95004 ("mm: differentiate page_mapped() from page_mapcount() for compound pages") Signed-off-by: Steve Capper Acked-by: Kirill A. Shutemov Cc: Will Deacon Cc: Catalin Marinas Cc: Michal Hocko Cc: Ingo Molnar Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

cgroup, cpuset: replace cpuset_post_attach_flush() with cgroup_subsys->post_attach callback

2016-05-04T21:49:09+00:00

commit 5cf1cacb49aee39c3e02ae87068fc3c6430659b0 upstream. Since e93ad19d0564 ("cpuset: make mm migration asynchronous"), cpuset kicks off asynchronous NUMA node migration if necessary during task migration and flushes it from cpuset_post_attach_flush() which is called at the end of __cgroup_procs_write(). This is to avoid performing migration with cgroup_threadgroup_rwsem write-locked which can lead to deadlock through dependency on kworker creation. memcg has a similar issue with charge moving, so let's convert it to an official callback rather than the current one-off cpuset specific function. This patch adds cgroup_subsys->post_attach callback and makes cpuset register cpuset_post_attach_flush() as its ->post_attach. The conversion is mostly one-to-one except that the new callback is called under cgroup_mutex. This is to guarantee that no other migration operations are started before ->post_attach callbacks are finished. cgroup_mutex is one of the outermost mutex in the system and has never been and shouldn't be a problem. We can add specialized synchronization around __cgroup_procs_write() but I don't think there's any noticeable benefit. Signed-off-by: Tejun Heo Cc: Li Zefan Cc: Johannes Weiner Cc: Michal Hocko Signed-off-by: Greg Kroah-Hartman

IB/mlx5: Expose correct max_sge_rd limit

2016-05-04T21:49:09+00:00

commit 986ef95ecdd3eb6fa29433e68faa94c7624083be upstream. mlx5 devices (Connect-IB, ConnectX-4, ConnectX-4-LX) has a limitation where rdma read work queue entries cannot exceed 512 bytes. A rdma_read wqe needs to fit in 512 bytes: - wqe control segment (16 bytes) - rdma segment (16 bytes) - scatter elements (16 bytes each) So max_sge_rd should be: (512 - 16 - 16) / 16 = 30. Reported-by: Christoph Hellwig Tested-by: Christoph Hellwig Signed-off-by: Sagi Grimberg Signed-off-by: Leon Romanovsky Signed-off-by: Doug Ledford Signed-off-by: Greg Kroah-Hartman

fs: add file_dentry()

2016-04-20T06:45:23+00:00

commit d101a125954eae1d397adda94ca6319485a50493 upstream. This series fixes bugs in nfs and ext4 due to 4bacc9c9234c ("overlayfs: Make f_path always point to the overlay and f_inode to the underlay"). Regular files opened on overlayfs will result in the file being opened on the underlying filesystem, while f_path points to the overlayfs mount/dentry. This confuses filesystems which get the dentry from struct file and assume it's theirs. Add a new helper, file_dentry() [*], to get the filesystem's own dentry from the file. This checks file->f_path.dentry->d_flags against DCACHE_OP_REAL, and returns file->f_path.dentry if DCACHE_OP_REAL is not set (this is the common, non-overlayfs case). In the uncommon case it will call into overlayfs's ->d_real() to get the underlying dentry, matching file_inode(file). The reason we need to check against the inode is that if the file is copied up while being open, d_real() would return the upper dentry, while the open file comes from the lower dentry. [*] If possible, it's better simply to use file_inode() instead. Signed-off-by: Miklos Szeredi Signed-off-by: Theodore Ts'o Tested-by: Goldwyn Rodrigues Reviewed-by: Trond Myklebust Cc: David Howells Cc: Al Viro Cc: Daniel Axtens Signed-off-by: Greg Kroah-Hartman

USB: uas: Add a new NO_REPORT_LUNS quirk

2016-04-20T06:45:18+00:00

commit 1363074667a6b7d0507527742ccd7bbed5e3ceaa upstream. Add a new NO_REPORT_LUNS quirk and set it for Seagate drives with an usb-id of: 0bc2:331a, as these will fail to respond to a REPORT_LUNS command. Reported-and-tested-by: David Webb Signed-off-by: Hans de Goede Acked-by: Alan Stern Signed-off-by: Greg Kroah-Hartman