<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/tools/testing/nvdimm/test, branch v5.5</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>tools/testing/nvdimm: Fix mock support for ioremap</title>
<updated>2019-12-12T01:11:10+00:00</updated>
<author>
<name>Dan Williams</name>
<email>dan.j.williams@intel.com</email>
</author>
<published>2019-11-14T00:22:06+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=c1468554776229d0db69e74a9aaf6f7e7095fd51'/>
<id>c1468554776229d0db69e74a9aaf6f7e7095fd51</id>
<content type='text'>
After commit d092a8707326 "arch: rely on asm-generic/io.h for default
ioremap_* definitions" the ioremap_nocache() symbol has been replaced
with ioremap(). Update the mocked symbol list for nvdimm testing.

Link: https://lore.kernel.org/r/157369090817.2974548.10148423996292973088.stgit@dwillia2-desk3.amr.corp.intel.com
Fixes: d092a8707326 ("arch: rely on asm-generic/io.h for default ioremap_* definitions")
Signed-off-by: Dan Williams &lt;dan.j.williams@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
After commit d092a8707326 "arch: rely on asm-generic/io.h for default
ioremap_* definitions" the ioremap_nocache() symbol has been replaced
with ioremap(). Update the mocked symbol list for nvdimm testing.

Link: https://lore.kernel.org/r/157369090817.2974548.10148423996292973088.stgit@dwillia2-desk3.amr.corp.intel.com
Fixes: d092a8707326 ("arch: rely on asm-generic/io.h for default ioremap_* definitions")
Signed-off-by: Dan Williams &lt;dan.j.williams@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'libnvdimm-fixes-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm</title>
<updated>2019-09-29T17:33:41+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2019-09-29T17:33:41+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=a3c0e7b1fe1fc62bba5f591c4bc404eea96823b8'/>
<id>a3c0e7b1fe1fc62bba5f591c4bc404eea96823b8</id>
<content type='text'>
More libnvdimm updates from Dan Williams:

 - Complete the reworks to interoperate with powerpc dynamic huge page
   sizes

 - Fix a crash due to missed accounting for the powerpc 'struct
   page'-memmap mapping granularity

 - Fix badblock initialization for volatile (DRAM emulated) pmem ranges

 - Stop triggering request_key() notifications to userspace when
   NVDIMM-security is disabled / not present

 - Miscellaneous small fixups

* tag 'libnvdimm-fixes-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  libnvdimm/region: Enable MAP_SYNC for volatile regions
  libnvdimm: prevent nvdimm from requesting key when security is disabled
  libnvdimm/region: Initialize bad block for volatile namespaces
  libnvdimm/nfit_test: Fix acpi_handle redefinition
  libnvdimm/altmap: Track namespace boundaries in altmap
  libnvdimm: Fix endian conversion issues 
  libnvdimm/dax: Pick the right alignment default when creating dax devices
  powerpc/book3s64: Export has_transparent_hugepage() related functions.
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
More libnvdimm updates from Dan Williams:

 - Complete the reworks to interoperate with powerpc dynamic huge page
   sizes

 - Fix a crash due to missed accounting for the powerpc 'struct
   page'-memmap mapping granularity

 - Fix badblock initialization for volatile (DRAM emulated) pmem ranges

 - Stop triggering request_key() notifications to userspace when
   NVDIMM-security is disabled / not present

 - Miscellaneous small fixups

* tag 'libnvdimm-fixes-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  libnvdimm/region: Enable MAP_SYNC for volatile regions
  libnvdimm: prevent nvdimm from requesting key when security is disabled
  libnvdimm/region: Initialize bad block for volatile namespaces
  libnvdimm/nfit_test: Fix acpi_handle redefinition
  libnvdimm/altmap: Track namespace boundaries in altmap
  libnvdimm: Fix endian conversion issues 
  libnvdimm/dax: Pick the right alignment default when creating dax devices
  powerpc/book3s64: Export has_transparent_hugepage() related functions.
</pre>
</div>
</content>
</entry>
<entry>
<title>libnvdimm/nfit_test: Fix acpi_handle redefinition</title>
<updated>2019-09-24T17:24:18+00:00</updated>
<author>
<name>Nathan Chancellor</name>
<email>natechancellor@gmail.com</email>
</author>
<published>2019-09-18T04:21:49+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=59f08896f058a92f03a0041b397a1a227c5e8529'/>
<id>59f08896f058a92f03a0041b397a1a227c5e8529</id>
<content type='text'>
After commit 62974fc389b3 ("libnvdimm: Enable unit test infrastructure
compile checks"), clang warns:

In file included from
../drivers/nvdimm/../../tools/testing/nvdimm/test/iomap.c:15:
../drivers/nvdimm/../../tools/testing/nvdimm/test/nfit_test.h:206:15:
warning: redefinition of typedef 'acpi_handle' is a C11 feature
[-Wtypedef-redefinition]
typedef void *acpi_handle;
              ^
../include/acpi/actypes.h:424:15: note: previous definition is here
typedef void *acpi_handle;      /* Actually a ptr to a NS Node */
              ^
1 warning generated.

The include chain:

iomap.c -&gt;
    linux/acpi.h -&gt;
        acpi/acpi.h -&gt;
            acpi/actypes.h
    nfit_test.h

Avoid this by including linux/acpi.h in nfit_test.h, which allows us to
remove both the typedef and the forward declaration of acpi_object.

Link: https://github.com/ClangBuiltLinux/linux/issues/660
Signed-off-by: Nathan Chancellor &lt;natechancellor@gmail.com&gt;
Reviewed-by: Ira Weiny &lt;ira.weiny@intel.com&gt;
Link: https://lore.kernel.org/r/20190918042148.77553-1-natechancellor@gmail.com
Signed-off-by: Dan Williams &lt;dan.j.williams@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
After commit 62974fc389b3 ("libnvdimm: Enable unit test infrastructure
compile checks"), clang warns:

In file included from
../drivers/nvdimm/../../tools/testing/nvdimm/test/iomap.c:15:
../drivers/nvdimm/../../tools/testing/nvdimm/test/nfit_test.h:206:15:
warning: redefinition of typedef 'acpi_handle' is a C11 feature
[-Wtypedef-redefinition]
typedef void *acpi_handle;
              ^
../include/acpi/actypes.h:424:15: note: previous definition is here
typedef void *acpi_handle;      /* Actually a ptr to a NS Node */
              ^
1 warning generated.

The include chain:

iomap.c -&gt;
    linux/acpi.h -&gt;
        acpi/acpi.h -&gt;
            acpi/actypes.h
    nfit_test.h

Avoid this by including linux/acpi.h in nfit_test.h, which allows us to
remove both the typedef and the forward declaration of acpi_object.

Link: https://github.com/ClangBuiltLinux/linux/issues/660
Signed-off-by: Nathan Chancellor &lt;natechancellor@gmail.com&gt;
Reviewed-by: Ira Weiny &lt;ira.weiny@intel.com&gt;
Link: https://lore.kernel.org/r/20190918042148.77553-1-natechancellor@gmail.com
Signed-off-by: Dan Williams &lt;dan.j.williams@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'libnvdimm-for-5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm</title>
<updated>2019-09-21T17:55:29+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2019-09-21T17:55:29+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=6cb2e9ee51b5f1539f027346a02904e282b87d4d'/>
<id>6cb2e9ee51b5f1539f027346a02904e282b87d4d</id>
<content type='text'>
Pull libnvdimm updates from Dan Williams:
 "Some reworks to better support nvdimms on powerpc and an nvdimm
  security interface update:

   - Rework the nvdimm core to accommodate architectures with different
     page sizes and ones that can change supported huge page sizes at
     boot time rather than a compile time constant.

   - Introduce a distinct 'frozen' attribute for the nvdimm security
     state since it is independent of the locked state.

   - Miscellaneous fixups"

* tag 'libnvdimm-for-5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  libnvdimm: Use PAGE_SIZE instead of SZ_4K for align check
  libnvdimm/label: Remove the dpa align check
  libnvdimm/pfn_dev: Add page size and struct page size to pfn superblock
  libnvdimm/pfn_dev: Add a build check to make sure we notice when struct page size change
  libnvdimm/pmem: Advance namespace seed for specific probe errors
  libnvdimm/region: Rewrite _probe_success() to _advance_seeds()
  libnvdimm/security: Consolidate 'security' operations
  libnvdimm/security: Tighten scope of nvdimm-&gt;busy vs security operations
  libnvdimm/security: Introduce a 'frozen' attribute
  libnvdimm, region: Use struct_size() in kzalloc()
  tools/testing/nvdimm: Fix fallthrough warning
  libnvdimm/of_pmem: Provide a unique name for bus provider
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull libnvdimm updates from Dan Williams:
 "Some reworks to better support nvdimms on powerpc and an nvdimm
  security interface update:

   - Rework the nvdimm core to accommodate architectures with different
     page sizes and ones that can change supported huge page sizes at
     boot time rather than a compile time constant.

   - Introduce a distinct 'frozen' attribute for the nvdimm security
     state since it is independent of the locked state.

   - Miscellaneous fixups"

* tag 'libnvdimm-for-5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  libnvdimm: Use PAGE_SIZE instead of SZ_4K for align check
  libnvdimm/label: Remove the dpa align check
  libnvdimm/pfn_dev: Add page size and struct page size to pfn superblock
  libnvdimm/pfn_dev: Add a build check to make sure we notice when struct page size change
  libnvdimm/pmem: Advance namespace seed for specific probe errors
  libnvdimm/region: Rewrite _probe_success() to _advance_seeds()
  libnvdimm/security: Consolidate 'security' operations
  libnvdimm/security: Tighten scope of nvdimm-&gt;busy vs security operations
  libnvdimm/security: Introduce a 'frozen' attribute
  libnvdimm, region: Use struct_size() in kzalloc()
  tools/testing/nvdimm: Fix fallthrough warning
  libnvdimm/of_pmem: Provide a unique name for bus provider
</pre>
</div>
</content>
</entry>
<entry>
<title>memremap: remove the dev field in struct dev_pagemap</title>
<updated>2019-08-20T12:41:35+00:00</updated>
<author>
<name>Christoph Hellwig</name>
<email>hch@lst.de</email>
</author>
<published>2019-08-18T09:05:55+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=fdc029b19dfd190840d23e5c70bd231140b0e4a4'/>
<id>fdc029b19dfd190840d23e5c70bd231140b0e4a4</id>
<content type='text'>
The dev field in struct dev_pagemap is only used to print dev_name in two
places, which are at best nice to have.  Just remove the field and thus
the name in those two messages.

Link: https://lore.kernel.org/r/20190818090557.17853-3-hch@lst.de
Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Reviewed-by: Ira Weiny &lt;ira.weiny@intel.com&gt;
Reviewed-by: Dan Williams &lt;dan.j.williams@intel.com&gt;
Tested-by: Bharata B Rao &lt;bharata@linux.ibm.com&gt;
Reviewed-by: Jason Gunthorpe &lt;jgg@mellanox.com&gt;
Signed-off-by: Jason Gunthorpe &lt;jgg@mellanox.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The dev field in struct dev_pagemap is only used to print dev_name in two
places, which are at best nice to have.  Just remove the field and thus
the name in those two messages.

Link: https://lore.kernel.org/r/20190818090557.17853-3-hch@lst.de
Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Reviewed-by: Ira Weiny &lt;ira.weiny@intel.com&gt;
Reviewed-by: Dan Williams &lt;dan.j.williams@intel.com&gt;
Tested-by: Bharata B Rao &lt;bharata@linux.ibm.com&gt;
Reviewed-by: Jason Gunthorpe &lt;jgg@mellanox.com&gt;
Signed-off-by: Jason Gunthorpe &lt;jgg@mellanox.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tools/testing/nvdimm: Fix fallthrough warning</title>
<updated>2019-08-15T01:04:39+00:00</updated>
<author>
<name>Dan Williams</name>
<email>dan.j.williams@intel.com</email>
</author>
<published>2019-08-07T21:31:11+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=5518ba4ebd7d1e15fc558af05fa600198535f074'/>
<id>5518ba4ebd7d1e15fc558af05fa600198535f074</id>
<content type='text'>
Use the expected 'fall through' designation to fix:

    tools/testing/nvdimm/test/nfit.c: In function ‘nd_intel_test_finish_query’:
    tools/testing/nvdimm/test/nfit.c:433:13: warning: this statement may fall through [-Wimplicit-fallthrough=]
       fw-&gt;state = FW_STATE_UPDATED;
       ~~~~~~~~~~^~~~~~~~~~~~~~~~~~
    tools/testing/nvdimm/test/nfit.c:435:2: note: here
      case FW_STATE_UPDATED:
      ^~~~

Reviewed-by: Vishal Verma &lt;vishal.l.verma@intel.com&gt;
Link: https://lore.kernel.org/r/156521347159.1442374.1381360879102718899.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams &lt;dan.j.williams@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Use the expected 'fall through' designation to fix:

    tools/testing/nvdimm/test/nfit.c: In function ‘nd_intel_test_finish_query’:
    tools/testing/nvdimm/test/nfit.c:433:13: warning: this statement may fall through [-Wimplicit-fallthrough=]
       fw-&gt;state = FW_STATE_UPDATED;
       ~~~~~~~~~~^~~~~~~~~~~~~~~~~~
    tools/testing/nvdimm/test/nfit.c:435:2: note: here
      case FW_STATE_UPDATED:
      ^~~~

Reviewed-by: Vishal Verma &lt;vishal.l.verma@intel.com&gt;
Link: https://lore.kernel.org/r/156521347159.1442374.1381360879102718899.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams &lt;dan.j.williams@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>memremap: provide an optional internal refcount in struct dev_pagemap</title>
<updated>2019-07-02T17:32:44+00:00</updated>
<author>
<name>Christoph Hellwig</name>
<email>hch@lst.de</email>
</author>
<published>2019-06-26T12:27:14+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=24917f6b1041a73993178920656e13364f847995'/>
<id>24917f6b1041a73993178920656e13364f847995</id>
<content type='text'>
Provide an internal refcounting logic if no -&gt;ref field is provided
in the pagemap passed into devm_memremap_pages so that callers don't
have to reinvent it poorly.

Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Reviewed-by: Ira Weiny &lt;ira.weiny@intel.com&gt;
Reviewed-by: Dan Williams &lt;dan.j.williams@intel.com&gt;
Tested-by: Dan Williams &lt;dan.j.williams@intel.com&gt;
Signed-off-by: Jason Gunthorpe &lt;jgg@mellanox.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Provide an internal refcounting logic if no -&gt;ref field is provided
in the pagemap passed into devm_memremap_pages so that callers don't
have to reinvent it poorly.

Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Reviewed-by: Ira Weiny &lt;ira.weiny@intel.com&gt;
Reviewed-by: Dan Williams &lt;dan.j.williams@intel.com&gt;
Tested-by: Dan Williams &lt;dan.j.williams@intel.com&gt;
Signed-off-by: Jason Gunthorpe &lt;jgg@mellanox.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>memremap: pass a struct dev_pagemap to -&gt;kill and -&gt;cleanup</title>
<updated>2019-07-02T17:32:44+00:00</updated>
<author>
<name>Christoph Hellwig</name>
<email>hch@lst.de</email>
</author>
<published>2019-06-26T12:27:09+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=d8668bb0451c3c45b59dbcde2654e0539aad1d2a'/>
<id>d8668bb0451c3c45b59dbcde2654e0539aad1d2a</id>
<content type='text'>
Passing the actual typed structure leads to more understandable code
vs just passing the ref member.

Reported-by: Logan Gunthorpe &lt;logang@deltatee.com&gt;
Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Reviewed-by: Logan Gunthorpe &lt;logang@deltatee.com&gt;
Reviewed-by: Jason Gunthorpe &lt;jgg@mellanox.com&gt;
Reviewed-by: Dan Williams &lt;dan.j.williams@intel.com&gt;
Tested-by: Dan Williams &lt;dan.j.williams@intel.com&gt;
Signed-off-by: Jason Gunthorpe &lt;jgg@mellanox.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Passing the actual typed structure leads to more understandable code
vs just passing the ref member.

Reported-by: Logan Gunthorpe &lt;logang@deltatee.com&gt;
Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Reviewed-by: Logan Gunthorpe &lt;logang@deltatee.com&gt;
Reviewed-by: Jason Gunthorpe &lt;jgg@mellanox.com&gt;
Reviewed-by: Dan Williams &lt;dan.j.williams@intel.com&gt;
Tested-by: Dan Williams &lt;dan.j.williams@intel.com&gt;
Signed-off-by: Jason Gunthorpe &lt;jgg@mellanox.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>memremap: move dev_pagemap callbacks into a separate structure</title>
<updated>2019-07-02T17:32:44+00:00</updated>
<author>
<name>Christoph Hellwig</name>
<email>hch@lst.de</email>
</author>
<published>2019-06-26T12:27:08+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=1e240e8d4a7d92232b6214e02a0a4197a53afd6c'/>
<id>1e240e8d4a7d92232b6214e02a0a4197a53afd6c</id>
<content type='text'>
The dev_pagemap is a growing too many callbacks.  Move them into a
separate ops structure so that they are not duplicated for multiple
instances, and an attacker can't easily overwrite them.

Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Reviewed-by: Logan Gunthorpe &lt;logang@deltatee.com&gt;
Reviewed-by: Jason Gunthorpe &lt;jgg@mellanox.com&gt;
Reviewed-by: Dan Williams &lt;dan.j.williams@intel.com&gt;
Tested-by: Dan Williams &lt;dan.j.williams@intel.com&gt;
Signed-off-by: Jason Gunthorpe &lt;jgg@mellanox.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The dev_pagemap is a growing too many callbacks.  Move them into a
separate ops structure so that they are not duplicated for multiple
instances, and an attacker can't easily overwrite them.

Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Reviewed-by: Logan Gunthorpe &lt;logang@deltatee.com&gt;
Reviewed-by: Jason Gunthorpe &lt;jgg@mellanox.com&gt;
Reviewed-by: Dan Williams &lt;dan.j.williams@intel.com&gt;
Tested-by: Dan Williams &lt;dan.j.williams@intel.com&gt;
Signed-off-by: Jason Gunthorpe &lt;jgg@mellanox.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>mm/devm_memremap_pages: fix final page put race</title>
<updated>2019-06-14T03:34:56+00:00</updated>
<author>
<name>Dan Williams</name>
<email>dan.j.williams@intel.com</email>
</author>
<published>2019-06-13T22:56:33+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=50f44ee7248ad2f7984ef081974a6ecd09724b3e'/>
<id>50f44ee7248ad2f7984ef081974a6ecd09724b3e</id>
<content type='text'>
Logan noticed that devm_memremap_pages_release() kills the percpu_ref
drops all the page references that were acquired at init and then
immediately proceeds to unplug, arch_remove_memory(), the backing pages
for the pagemap.  If for some reason device shutdown actually collides
with a busy / elevated-ref-count page then arch_remove_memory() should
be deferred until after that reference is dropped.

As it stands the "wait for last page ref drop" happens *after*
devm_memremap_pages_release() returns, which is obviously too late and
can lead to crashes.

Fix this situation by assigning the responsibility to wait for the
percpu_ref to go idle to devm_memremap_pages() with a new -&gt;cleanup()
callback.  Implement the new cleanup callback for all
devm_memremap_pages() users: pmem, devdax, hmm, and p2pdma.

Link: http://lkml.kernel.org/r/155727339156.292046.5432007428235387859.stgit@dwillia2-desk3.amr.corp.intel.com
Fixes: 41e94a851304 ("add devm_memremap_pages")
Signed-off-by: Dan Williams &lt;dan.j.williams@intel.com&gt;
Reported-by: Logan Gunthorpe &lt;logang@deltatee.com&gt;
Reviewed-by: Ira Weiny &lt;ira.weiny@intel.com&gt;
Reviewed-by: Logan Gunthorpe &lt;logang@deltatee.com&gt;
Cc: Bjorn Helgaas &lt;bhelgaas@google.com&gt;
Cc: "Jérôme Glisse" &lt;jglisse@redhat.com&gt;
Cc: Christoph Hellwig &lt;hch@lst.de&gt;
Cc: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Cc: "Rafael J. Wysocki" &lt;rafael@kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Logan noticed that devm_memremap_pages_release() kills the percpu_ref
drops all the page references that were acquired at init and then
immediately proceeds to unplug, arch_remove_memory(), the backing pages
for the pagemap.  If for some reason device shutdown actually collides
with a busy / elevated-ref-count page then arch_remove_memory() should
be deferred until after that reference is dropped.

As it stands the "wait for last page ref drop" happens *after*
devm_memremap_pages_release() returns, which is obviously too late and
can lead to crashes.

Fix this situation by assigning the responsibility to wait for the
percpu_ref to go idle to devm_memremap_pages() with a new -&gt;cleanup()
callback.  Implement the new cleanup callback for all
devm_memremap_pages() users: pmem, devdax, hmm, and p2pdma.

Link: http://lkml.kernel.org/r/155727339156.292046.5432007428235387859.stgit@dwillia2-desk3.amr.corp.intel.com
Fixes: 41e94a851304 ("add devm_memremap_pages")
Signed-off-by: Dan Williams &lt;dan.j.williams@intel.com&gt;
Reported-by: Logan Gunthorpe &lt;logang@deltatee.com&gt;
Reviewed-by: Ira Weiny &lt;ira.weiny@intel.com&gt;
Reviewed-by: Logan Gunthorpe &lt;logang@deltatee.com&gt;
Cc: Bjorn Helgaas &lt;bhelgaas@google.com&gt;
Cc: "Jérôme Glisse" &lt;jglisse@redhat.com&gt;
Cc: Christoph Hellwig &lt;hch@lst.de&gt;
Cc: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Cc: "Rafael J. Wysocki" &lt;rafael@kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
