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  1. 03 Jun, 2019 6 commits
    • Laurentiu Tudor's avatar
      USB: use genalloc for USB HCs with local memory · b0310c2f
      Laurentiu Tudor authored 
      For HCs that have local memory, replace the current DMA API usage with
a genalloc generic allocator to manage the mappings for these devices.
To help users, introduce a new HCD API, usb_hcd_setup_local_mem() that
will setup up the genalloc backing up the device local memory. It will
be used in subsequent patches.  This is in preparation for dropping
the existing "coherent" dma mem declaration APIs.  The current
implementation was relying on a short circuit in the DMA API that in
the end, was acting as an allocator for these type of devices.
Signed-off-by: default avatarLaurentiu Tudor <laurentiu.tudor@nxp.com>
Tested-by: default avatarFredrik Noring <noring@nocrew.org>
Reviewed-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
      b0310c2f
    • Fredrik Noring's avatar
      lib/genalloc: add gen_pool_dma_zalloc() for zeroed DMA allocations · da83a722
      Fredrik Noring authored 
      gen_pool_dma_zalloc() is a zeroed memory variant of
gen_pool_dma_alloc().  Also document the return values of both, and
indicate NULL as a "%NULL" constant.
Signed-off-by: default avatarFredrik Noring <noring@nocrew.org>
Reviewed-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
      da83a722
    • Nicolin Chen's avatar
      dma-contiguous: fix !CONFIG_DMA_CMA version of dma_{alloc, free}_contiguous() · dd3dcede
      Nicolin Chen authored 
      Commit fdaeec198ada ("dma-contiguous: add dma_{alloc,free}_contiguous()
helpers") adds a pair of new helper functions so as to abstract code in
the dma-direct (and other places in the future), however it breaks QEMU
boot feature using x86_64 defconfig.

That's because x86_64 defconfig has CONFIG_DMA_CMA=n so those two newly
introduced helper functions are empty in their !CONFIG_DMA_CMA version,
while previously the platform independent dma-direct code had fallback
alloc_pages_node() and __free_pages().

So this patch fixes it by adding alloc_pages_node() and __free_pages()
in the !CONFIG_DMA_CMA version of the two helper functions.

Tested with below QEMU command:
  qemu-system-x86_64 -m 512m \
      -drive file=images/x86_64/rootfs.ext4,format=raw,if=ide \
      -append 'console=ttyS0 root=/dev/sda' -nographic \
      -kernel arch/x86_64/boot/bzImage

with the rootfs from the below link:
  https://github.com/ClangBuiltLinux/continuous-integration/raw/master/images/x86_64/rootfs.ext4

Fixes: fdaeec198ada ("dma-contiguous: add dma_{alloc,free}_contiguous() helpers")
Reported-by: default avatarNathan Chancellor <natechancellor@gmail.com>
Signed-off-by: default avatarNicolin Chen <nicoleotsuka@gmail.com>
Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
      dd3dcede
    • Nicolin Chen's avatar
      dma-contiguous: use fallback alloc_pages for single pages · bd2e7563
      Nicolin Chen authored 
      The addresses within a single page are always contiguous, so it's
not so necessary to always allocate one single page from CMA area.
Since the CMA area has a limited predefined size of space, it may
run out of space in heavy use cases, where there might be quite a
lot CMA pages being allocated for single pages.

However, there is also a concern that a device might care where a
page comes from -- it might expect the page from CMA area and act
differently if the page doesn't.

This patch tries to use the fallback alloc_pages path, instead of
one-page size allocations from the global CMA area in case that a
device does not have its own CMA area. This'd save resources from
the CMA global area for more CMA allocations, and also reduce CMA
fragmentations resulted from trivial allocations.
Signed-off-by: default avatarNicolin Chen <nicoleotsuka@gmail.com>
Tested-by: default avatardann frazier <dann.frazier@canonical.com>
Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
      bd2e7563
    • Nicolin Chen's avatar
      dma-contiguous: add dma_{alloc,free}_contiguous() helpers · b1d2dc00
      Nicolin Chen authored 
      Both dma_alloc_from_contiguous() and dma_release_from_contiguous() are
very simply implemented, but requiring callers to pass certain
parameters like count and align, and taking a boolean parameter to check
__GFP_NOWARN in the allocation flags. So every function call duplicates
similar work:

	unsigned long order = get_order(size);
	size_t count = size >> PAGE_SHIFT;

	page = dma_alloc_from_contiguous(dev, count, order,
			gfp & __GFP_NOWARN);

	[...]

	dma_release_from_contiguous(dev, page, size >> PAGE_SHIFT);

Additionally, as CMA can be used only in the context which permits
sleeping, most of callers do a gfpflags_allow_blocking() check and a
corresponding fallback allocation of normal pages upon any false result:

	if (gfpflags_allow_blocking(flag))
		page = dma_alloc_from_contiguous();
	if (!page)
		page = alloc_pages();

	[...]

	if (!dma_release_from_contiguous(dev, page, count))
		__free_pages(page, get_order(size));

So this patch simplifies those function calls by abstracting these
operations into the two new functions: dma_{alloc,free}_contiguous.

As some callers of dma_{alloc,release}_from_contiguous() might be
complicated, this patch just implements these two new functions to
kernel/dma/direct.c only as an initial step.
Suggested-by: default avatarChristoph Hellwig <hch@lst.de>
Signed-off-by: default avatarNicolin Chen <nicoleotsuka@gmail.com>
Tested-by: default avatardann frazier <dann.frazier@canonical.com>
Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
      b1d2dc00
    • Nathan Chancellor's avatar
      iommu/dma: Fix condition check in iommu_dma_unmap_sg · 1b961423
      Nathan Chancellor authored 
      Clang warns:

drivers/iommu/dma-iommu.c:897:6: warning: logical not is only applied to
the left hand side of this comparison [-Wlogical-not-parentheses]
        if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC) == 0)
            ^                                 ~~
drivers/iommu/dma-iommu.c:897:6: note: add parentheses after the '!' to
evaluate the comparison first
        if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC) == 0)
            ^
             (                                    )
drivers/iommu/dma-iommu.c:897:6: note: add parentheses around left hand
side expression to silence this warning
        if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC) == 0)
            ^
            (                                )
1 warning generated.

Judging from the rest of the commit and the conditional in
iommu_dma_map_sg, either

    if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))

or
    if ((attrs & DMA_ATTR_SKIP_CPU_SYNC) == 0)

was intended, not a combination of the two.

I personally think that the former is easier to understand so use that.

Fixes: 06d60728 ("iommu/dma: move the arm64 wrappers to common code")
Link: https://github.com/ClangBuiltLinux/linux/issues/497Signed-off-by: default avatarNathan Chancellor <natechancellor@gmail.com>
Reviewed-by: default avatarRobin Murphy <robin.murphy@arm.com>
Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
Signed-off-by: default avatarJoerg Roedel <jroedel@suse.de>
      1b961423
  3. 27 May, 2019 23 commits
  5. 26 May, 2019 6 commits
    • Linus Torvalds's avatar
      Linux 5.2-rc2 · cd6c84d8
      Linus Torvalds authored
      cd6c84d8
    • Linus Torvalds's avatar
      Merge tag 'trace-v5.2-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace · c5b44095
      Linus Torvalds authored 
      Pull tracing warning fix from Steven Rostedt:
 "Make the GCC 9 warning for sub struct memset go away.

  GCC 9 now warns about calling memset() on partial structures when it
  goes across multiple fields. This adds a helper for the place in
  tracing that does this type of clearing of a structure"

* tag 'trace-v5.2-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Silence GCC 9 array bounds warning
      c5b44095
    • Linus Torvalds's avatar
      Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm · 862f0a32
      Linus Torvalds authored 
      Pull KVM fixes from Paolo Bonzini:
 "The usual smattering of fixes and tunings that came in too late for
  the merge window, but should not wait four months before they appear
  in a release.

  I also travelled a bit more than usual in the first part of May, which
  didn't help with picking up patches and reports promptly"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (33 commits)
  KVM: x86: fix return value for reserved EFER
  tools/kvm_stat: fix fields filter for child events
  KVM: selftests: Wrap vcpu_nested_state_get/set functions with x86 guard
  kvm: selftests: aarch64: compile with warnings on
  kvm: selftests: aarch64: fix default vm mode
  kvm: selftests: aarch64: dirty_log_test: fix unaligned memslot size
  KVM: s390: fix memory slot handling for KVM_SET_USER_MEMORY_REGION
  KVM: x86/pmu: do not mask the value that is written to fixed PMUs
  KVM: x86/pmu: mask the result of rdpmc according to the width of the counters
  x86/kvm/pmu: Set AMD's virt PMU version to 1
  KVM: x86: do not spam dmesg with VMCS/VMCB dumps
  kvm: Check irqchip mode before assign irqfd
  kvm: svm/avic: fix off-by-one in checking host APIC ID
  KVM: selftests: do not blindly clobber registers in guest asm
  KVM: selftests: Remove duplicated TEST_ASSERT in hyperv_cpuid.c
  KVM: LAPIC: Expose per-vCPU timer_advance_ns to userspace
  KVM: LAPIC: Fix lapic_timer_advance_ns parameter overflow
  kvm: vmx: Fix -Wmissing-prototypes warnings
  KVM: nVMX: Fix using __this_cpu_read() in preemptible context
  kvm: fix compilation on s390
  ...
      862f0a32
    • Linus Torvalds's avatar
      Merge tag 'random_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random · 128f2bfa
      Linus Torvalds authored 
      Pull /dev/random fix from Ted Ts'o:
 "Fix a soft lockup regression when reading from /dev/random in early
  boot"

* tag 'random_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random:
  random: fix soft lockup when trying to read from an uninitialized blocking pool
      128f2bfa
    • Theodore Ts'o's avatar
      random: fix soft lockup when trying to read from an uninitialized blocking pool · 58be0106
      Theodore Ts'o authored 
      Fixes: eb9d1bf0: "random: only read from /dev/random after its pool has received 128 bits"
Reported-by: default avatarkernel test robot <lkp@intel.com>
Signed-off-by: default avatarTheodore Ts'o <tytso@mit.edu>
      58be0106
    • Miguel Ojeda's avatar
      tracing: Silence GCC 9 array bounds warning · 0c97bf86
      Miguel Ojeda authored 
      Starting with GCC 9, -Warray-bounds detects cases when memset is called
starting on a member of a struct but the size to be cleared ends up
writing over further members.

Such a call happens in the trace code to clear, at once, all members
after and including `seq` on struct trace_iterator:

    In function 'memset',
        inlined from 'ftrace_dump' at kernel/trace/trace.c:8914:3:
    ./include/linux/string.h:344:9: warning: '__builtin_memset' offset
    [8505, 8560] from the object at 'iter' is out of the bounds of
    referenced subobject 'seq' with type 'struct trace_seq' at offset
    4368 [-Warray-bounds]
      344 |  return __builtin_memset(p, c, size);
          |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~

In order to avoid GCC complaining about it, we compute the address
ourselves by adding the offsetof distance instead of referring
directly to the member.

Since there are two places doing this clear (trace.c and trace_kdb.c),
take the chance to move the workaround into a single place in
the internal header.

Link: http://lkml.kernel.org/r/20190523124535.GA12931@gmail.comSigned-off-by: default avatarMiguel Ojeda <miguel.ojeda.sandonis@gmail.com>
[ Removed unnecessary parenthesis around "iter" ]
Signed-off-by: default avatarSteven Rostedt (VMware) <rostedt@goodmis.org>
      0c97bf86
  7. 25 May, 2019 5 commits
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