<feed xmlns='http://www.w3.org/2005/Atom'>
<title>wireguard-linux/arch/nios2/mm, branch jd/unified-crypt-queue</title>
<subtitle>WireGuard for the Linux kernel</subtitle>
<id>https://git.zx2c4.com/wireguard-linux/atom/arch/nios2/mm?h=jd%2Funified-crypt-queue</id>
<link rel='self' href='https://git.zx2c4.com/wireguard-linux/atom/arch/nios2/mm?h=jd%2Funified-crypt-queue'/>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/wireguard-linux/'/>
<updated>2020-04-04T17:12:47Z</updated>
<entry>
<title>Merge tag 'dma-mapping-5.7' of git://git.infradead.org/users/hch/dma-mapping</title>
<updated>2020-04-04T17:12:47Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2020-04-04T17:12:47Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/wireguard-linux/commit/?id=6f43bae38269a55534e1f86a9917318167de6639'/>
<id>urn:sha1:6f43bae38269a55534e1f86a9917318167de6639</id>
<content type='text'>
Pull dma-mapping updates from Christoph Hellwig:

 - fix an integer overflow in the coherent pool (Kevin Grandemange)

 - provide support for in-place uncached remapping and use that for
   openrisc

 - fix the arm coherent allocator to take the bus limit into account

* tag 'dma-mapping-5.7' of git://git.infradead.org/users/hch/dma-mapping:
  ARM/dma-mapping: merge __dma_supported into arm_dma_supported
  ARM/dma-mapping: take the bus limit into account in __dma_alloc
  ARM/dma-mapping: remove get_coherent_dma_mask
  openrisc: use the generic in-place uncached DMA allocator
  dma-direct: provide a arch_dma_clear_uncached hook
  dma-direct: make uncached_kernel_address more general
  dma-direct: consolidate the error handling in dma_direct_alloc_pages
  dma-direct: remove the cached_kernel_address hook
  dma-coherent: fix integer overflow in the reserved-memory dma allocation
</content>
</entry>
<entry>
<title>mm: allow VM_FAULT_RETRY for multiple times</title>
<updated>2020-04-02T16:35:30Z</updated>
<author>
<name>Peter Xu</name>
<email>peterx@redhat.com</email>
</author>
<published>2020-04-02T04:08:45Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/wireguard-linux/commit/?id=4064b982706375025628094e51d11cf1a958a5d3'/>
<id>urn:sha1:4064b982706375025628094e51d11cf1a958a5d3</id>
<content type='text'>
The idea comes from a discussion between Linus and Andrea [1].

Before this patch we only allow a page fault to retry once.  We achieved
this by clearing the FAULT_FLAG_ALLOW_RETRY flag when doing
handle_mm_fault() the second time.  This was majorly used to avoid
unexpected starvation of the system by looping over forever to handle the
page fault on a single page.  However that should hardly happen, and after
all for each code path to return a VM_FAULT_RETRY we'll first wait for a
condition (during which time we should possibly yield the cpu) to happen
before VM_FAULT_RETRY is really returned.

This patch removes the restriction by keeping the FAULT_FLAG_ALLOW_RETRY
flag when we receive VM_FAULT_RETRY.  It means that the page fault handler
now can retry the page fault for multiple times if necessary without the
need to generate another page fault event.  Meanwhile we still keep the
FAULT_FLAG_TRIED flag so page fault handler can still identify whether a
page fault is the first attempt or not.

Then we'll have these combinations of fault flags (only considering
ALLOW_RETRY flag and TRIED flag):

  - ALLOW_RETRY and !TRIED:  this means the page fault allows to
                             retry, and this is the first try

  - ALLOW_RETRY and TRIED:   this means the page fault allows to
                             retry, and this is not the first try

  - !ALLOW_RETRY and !TRIED: this means the page fault does not allow
                             to retry at all

  - !ALLOW_RETRY and TRIED:  this is forbidden and should never be used

In existing code we have multiple places that has taken special care of
the first condition above by checking against (fault_flags &amp;
FAULT_FLAG_ALLOW_RETRY).  This patch introduces a simple helper to detect
the first retry of a page fault by checking against both (fault_flags &amp;
FAULT_FLAG_ALLOW_RETRY) and !(fault_flag &amp; FAULT_FLAG_TRIED) because now
even the 2nd try will have the ALLOW_RETRY set, then use that helper in
all existing special paths.  One example is in __lock_page_or_retry(), now
we'll drop the mmap_sem only in the first attempt of page fault and we'll
keep it in follow up retries, so old locking behavior will be retained.

This will be a nice enhancement for current code [2] at the same time a
supporting material for the future userfaultfd-writeprotect work, since in
that work there will always be an explicit userfault writeprotect retry
for protected pages, and if that cannot resolve the page fault (e.g., when
userfaultfd-writeprotect is used in conjunction with swapped pages) then
we'll possibly need a 3rd retry of the page fault.  It might also benefit
other potential users who will have similar requirement like userfault
write-protection.

GUP code is not touched yet and will be covered in follow up patch.

Please read the thread below for more information.

[1] https://lore.kernel.org/lkml/20171102193644.GB22686@redhat.com/
[2] https://lore.kernel.org/lkml/20181230154648.GB9832@redhat.com/

Suggested-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Suggested-by: Andrea Arcangeli &lt;aarcange@redhat.com&gt;
Signed-off-by: Peter Xu &lt;peterx@redhat.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Tested-by: Brian Geffon &lt;bgeffon@google.com&gt;
Cc: Bobby Powers &lt;bobbypowers@gmail.com&gt;
Cc: David Hildenbrand &lt;david@redhat.com&gt;
Cc: Denis Plotnikov &lt;dplotnikov@virtuozzo.com&gt;
Cc: "Dr . David Alan Gilbert" &lt;dgilbert@redhat.com&gt;
Cc: Hugh Dickins &lt;hughd@google.com&gt;
Cc: Jerome Glisse &lt;jglisse@redhat.com&gt;
Cc: Johannes Weiner &lt;hannes@cmpxchg.org&gt;
Cc: "Kirill A . Shutemov" &lt;kirill@shutemov.name&gt;
Cc: Martin Cracauer &lt;cracauer@cons.org&gt;
Cc: Marty McFadden &lt;mcfadden8@llnl.gov&gt;
Cc: Matthew Wilcox &lt;willy@infradead.org&gt;
Cc: Maya Gokhale &lt;gokhale2@llnl.gov&gt;
Cc: Mel Gorman &lt;mgorman@suse.de&gt;
Cc: Mike Kravetz &lt;mike.kravetz@oracle.com&gt;
Cc: Mike Rapoport &lt;rppt@linux.vnet.ibm.com&gt;
Cc: Pavel Emelyanov &lt;xemul@openvz.org&gt;
Link: http://lkml.kernel.org/r/20200220160246.9790-1-peterx@redhat.com
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>mm: introduce FAULT_FLAG_DEFAULT</title>
<updated>2020-04-02T16:35:29Z</updated>
<author>
<name>Peter Xu</name>
<email>peterx@redhat.com</email>
</author>
<published>2020-04-02T04:08:37Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/wireguard-linux/commit/?id=dde1607248328cdb7570e3a252e8fb76b3411d66'/>
<id>urn:sha1:dde1607248328cdb7570e3a252e8fb76b3411d66</id>
<content type='text'>
Although there're tons of arch-specific page fault handlers, most of them
are still sharing the same initial value of the page fault flags.  Say,
merely all of the page fault handlers would allow the fault to be retried,
and they also allow the fault to respond to SIGKILL.

Let's define a default value for the fault flags to replace those initial
page fault flags that were copied over.  With this, it'll be far easier to
introduce new fault flag that can be used by all the architectures instead
of touching all the archs.

Signed-off-by: Peter Xu &lt;peterx@redhat.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Tested-by: Brian Geffon &lt;bgeffon@google.com&gt;
Reviewed-by: David Hildenbrand &lt;david@redhat.com&gt;
Cc: Andrea Arcangeli &lt;aarcange@redhat.com&gt;
Cc: Bobby Powers &lt;bobbypowers@gmail.com&gt;
Cc: Denis Plotnikov &lt;dplotnikov@virtuozzo.com&gt;
Cc: "Dr . David Alan Gilbert" &lt;dgilbert@redhat.com&gt;
Cc: Hugh Dickins &lt;hughd@google.com&gt;
Cc: Jerome Glisse &lt;jglisse@redhat.com&gt;
Cc: Johannes Weiner &lt;hannes@cmpxchg.org&gt;
Cc: "Kirill A . Shutemov" &lt;kirill@shutemov.name&gt;
Cc: Martin Cracauer &lt;cracauer@cons.org&gt;
Cc: Marty McFadden &lt;mcfadden8@llnl.gov&gt;
Cc: Matthew Wilcox &lt;willy@infradead.org&gt;
Cc: Maya Gokhale &lt;gokhale2@llnl.gov&gt;
Cc: Mel Gorman &lt;mgorman@suse.de&gt;
Cc: Mike Kravetz &lt;mike.kravetz@oracle.com&gt;
Cc: Mike Rapoport &lt;rppt@linux.vnet.ibm.com&gt;
Cc: Pavel Emelyanov &lt;xemul@openvz.org&gt;
Link: http://lkml.kernel.org/r/20200220160238.9694-1-peterx@redhat.com
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>mm: introduce fault_signal_pending()</title>
<updated>2020-04-02T16:35:29Z</updated>
<author>
<name>Peter Xu</name>
<email>peterx@redhat.com</email>
</author>
<published>2020-04-02T04:08:06Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/wireguard-linux/commit/?id=4ef873226ceb9c7bf11a922caddc5698a24bcfaf'/>
<id>urn:sha1:4ef873226ceb9c7bf11a922caddc5698a24bcfaf</id>
<content type='text'>
For most architectures, we've got a quick path to detect fatal signal
after a handle_mm_fault().  Introduce a helper for that quick path.

It cleans the current codes a bit so we don't need to duplicate the same
check across archs.  More importantly, this will be an unified place that
we handle the signal immediately right after an interrupted page fault, so
it'll be much easier for us if we want to change the behavior of handling
signals later on for all the archs.

Note that currently only part of the archs are using this new helper,
because some archs have their own way to handle signals.  In the follow up
patches, we'll try to apply this helper to all the rest of archs.

Another note is that the "regs" parameter in the new helper is not used
yet.  It'll be used very soon.  Now we kept it in this patch only to avoid
touching all the archs again in the follow up patches.

[peterx@redhat.com: fix sparse warnings]
  Link: http://lkml.kernel.org/r/20200311145921.GD479302@xz-x1
Signed-off-by: Peter Xu &lt;peterx@redhat.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Tested-by: Brian Geffon &lt;bgeffon@google.com&gt;
Cc: Andrea Arcangeli &lt;aarcange@redhat.com&gt;
Cc: Bobby Powers &lt;bobbypowers@gmail.com&gt;
Cc: David Hildenbrand &lt;david@redhat.com&gt;
Cc: Denis Plotnikov &lt;dplotnikov@virtuozzo.com&gt;
Cc: "Dr . David Alan Gilbert" &lt;dgilbert@redhat.com&gt;
Cc: Hugh Dickins &lt;hughd@google.com&gt;
Cc: Jerome Glisse &lt;jglisse@redhat.com&gt;
Cc: Johannes Weiner &lt;hannes@cmpxchg.org&gt;
Cc: "Kirill A . Shutemov" &lt;kirill@shutemov.name&gt;
Cc: Martin Cracauer &lt;cracauer@cons.org&gt;
Cc: Marty McFadden &lt;mcfadden8@llnl.gov&gt;
Cc: Matthew Wilcox &lt;willy@infradead.org&gt;
Cc: Maya Gokhale &lt;gokhale2@llnl.gov&gt;
Cc: Mel Gorman &lt;mgorman@suse.de&gt;
Cc: Mike Kravetz &lt;mike.kravetz@oracle.com&gt;
Cc: Mike Rapoport &lt;rppt@linux.vnet.ibm.com&gt;
Cc: Pavel Emelyanov &lt;xemul@openvz.org&gt;
Link: http://lkml.kernel.org/r/20200220155353.8676-4-peterx@redhat.com
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>dma-direct: make uncached_kernel_address more general</title>
<updated>2020-03-16T09:48:09Z</updated>
<author>
<name>Christoph Hellwig</name>
<email>hch@lst.de</email>
</author>
<published>2020-02-21T23:55:43Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/wireguard-linux/commit/?id=fa7e2247c5729f990c7456fe09f3af99c8f2571b'/>
<id>urn:sha1:fa7e2247c5729f990c7456fe09f3af99c8f2571b</id>
<content type='text'>
Rename the symbol to arch_dma_set_uncached, and pass a size to it as
well as allow an error return.  That will allow reusing this hook for
in-place pagetable remapping.

As the in-place remap doesn't always require an explicit cache flush,
also detangle ARCH_HAS_DMA_PREP_COHERENT from ARCH_HAS_DMA_SET_UNCACHED.

Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Reviewed-by: Robin Murphy &lt;robin.murphy@arm.com&gt;
</content>
</entry>
<entry>
<title>dma-direct: remove the cached_kernel_address hook</title>
<updated>2020-03-16T09:48:02Z</updated>
<author>
<name>Christoph Hellwig</name>
<email>hch@lst.de</email>
</author>
<published>2020-02-21T20:24:02Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/wireguard-linux/commit/?id=4f8232bbf887123f78bcdca3dfd2b3dfa52a0112'/>
<id>urn:sha1:4f8232bbf887123f78bcdca3dfd2b3dfa52a0112</id>
<content type='text'>
dma-direct now finds the kernel address for coherent allocations based
on the dma address, so the cached_kernel_address hooks is unused and
can be removed entirely.

Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Reviewed-by: Robin Murphy &lt;robin.murphy@arm.com&gt;
</content>
</entry>
<entry>
<title>nios2: Fix ioremap</title>
<updated>2019-12-12T08:34:33Z</updated>
<author>
<name>Guenter Roeck</name>
<email>linux@roeck-us.net</email>
</author>
<published>2019-12-12T08:34:03Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/wireguard-linux/commit/?id=e32ea127d81c12882f39c2783d78634597ff21a2'/>
<id>urn:sha1:e32ea127d81c12882f39c2783d78634597ff21a2</id>
<content type='text'>
Commit 5ace77e0b41a ("nios2: remove __ioremap") removed the following code,
with the argument that cacheflag is always 0 and the expression would
therefore always be false.

	if (IS_MAPPABLE_UNCACHEABLE(phys_addr) &amp;&amp;
	    IS_MAPPABLE_UNCACHEABLE(last_addr) &amp;&amp;
	    !(cacheflag &amp; _PAGE_CACHED))
		return (void __iomem *)(CONFIG_NIOS2_IO_REGION_BASE + phys_addr);

This did not take the "!" in the expression into account. Result is that
nios2 images no longer boot. Restoring the removed code fixes the problem.

Fixes: 5ace77e0b41a ("nios2: remove __ioremap")
Cc: Christoph Hellwig &lt;hch@lst.de&gt;
Signed-off-by: Guenter Roeck &lt;linux@roeck-us.net&gt;
Reviewed-by: Christoph Hellwig &lt;hch@lst.de&gt;
Signed-off-by: Ley Foon Tan &lt;ley.foon.tan@intel.com&gt;
</content>
</entry>
<entry>
<title>Merge branch '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</title>
<updated>2019-11-28T19:16:43Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2019-11-28T19:16:43Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/wireguard-linux/commit/?id=81b6b96475ac7a4ebfceae9f16fb3758327adbfe'/>
<id>urn:sha1:81b6b96475ac7a4ebfceae9f16fb3758327adbfe</id>
<content type='text'>
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-&gt;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()
  ...
</content>
</entry>
<entry>
<title>dma-mapping: drop the dev argument to arch_sync_dma_for_*</title>
<updated>2019-11-20T19:31:38Z</updated>
<author>
<name>Christoph Hellwig</name>
<email>hch@lst.de</email>
</author>
<published>2019-11-07T17:03:11Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/wireguard-linux/commit/?id=56e35f9c5b87ec1ae93e483284e189c84388de16'/>
<id>urn:sha1:56e35f9c5b87ec1ae93e483284e189c84388de16</id>
<content type='text'>
These are pure cache maintainance routines, so drop the unused
struct device argument.

Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Suggested-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
</content>
</entry>
<entry>
<title>nios2: remove __iounmap</title>
<updated>2019-11-11T20:18:19Z</updated>
<author>
<name>Christoph Hellwig</name>
<email>hch@lst.de</email>
</author>
<published>2019-08-13T06:11:46Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/wireguard-linux/commit/?id=3f3ded99aecf3498ac9a976ec2b02cf5c6281bd4'/>
<id>urn:sha1:3f3ded99aecf3498ac9a976ec2b02cf5c6281bd4</id>
<content type='text'>
No need to indirect iounmap for nios2.

Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
</content>
</entry>
</feed>
