<feed xmlns='http://www.w3.org/2005/Atom'>
<title>user/sven/linux.git/drivers/dax, branch v6.11.8</title>
<subtitle>Linux Kernel
</subtitle>
<id>https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v6.11.8</id>
<link rel='self' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v6.11.8'/>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/'/>
<updated>2024-10-17T13:27:00Z</updated>
<entry>
<title>device-dax: correct pgoff align in dax_set_mapping()</title>
<updated>2024-10-17T13:27:00Z</updated>
<author>
<name>Kun(llfl)</name>
<email>llfl@linux.alibaba.com</email>
</author>
<published>2024-09-27T07:45:09Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=e877427d218159ac29c9326100920d24330c9ee6'/>
<id>urn:sha1:e877427d218159ac29c9326100920d24330c9ee6</id>
<content type='text'>
commit 7fcbd9785d4c17ea533c42f20a9083a83f301fa6 upstream.

pgoff should be aligned using ALIGN_DOWN() instead of ALIGN().  Otherwise,
vmf-&gt;address not aligned to fault_size will be aligned to the next
alignment, that can result in memory failure getting the wrong address.

It's a subtle situation that only can be observed in
page_mapped_in_vma() after the page is page fault handled by
dev_dax_huge_fault.  Generally, there is little chance to perform
page_mapped_in_vma in dev-dax's page unless in specific error injection
to the dax device to trigger an MCE - memory-failure.  In that case,
page_mapped_in_vma() will be triggered to determine which task is
accessing the failure address and kill that task in the end.


We used self-developed dax device (which is 2M aligned mapping) , to
perform error injection to random address.  It turned out that error
injected to non-2M-aligned address was causing endless MCE until panic.
Because page_mapped_in_vma() kept resulting wrong address and the task
accessing the failure address was never killed properly:


[ 3783.719419] Memory failure: 0x200c9742: recovery action for dax page:
Recovered
[ 3784.049006] mce: Uncorrected hardware memory error in user-access at
200c9742380
[ 3784.049190] Memory failure: 0x200c9742: recovery action for dax page:
Recovered
[ 3784.448042] mce: Uncorrected hardware memory error in user-access at
200c9742380
[ 3784.448186] Memory failure: 0x200c9742: recovery action for dax page:
Recovered
[ 3784.792026] mce: Uncorrected hardware memory error in user-access at
200c9742380
[ 3784.792179] Memory failure: 0x200c9742: recovery action for dax page:
Recovered
[ 3785.162502] mce: Uncorrected hardware memory error in user-access at
200c9742380
[ 3785.162633] Memory failure: 0x200c9742: recovery action for dax page:
Recovered
[ 3785.461116] mce: Uncorrected hardware memory error in user-access at
200c9742380
[ 3785.461247] Memory failure: 0x200c9742: recovery action for dax page:
Recovered
[ 3785.764730] mce: Uncorrected hardware memory error in user-access at
200c9742380
[ 3785.764859] Memory failure: 0x200c9742: recovery action for dax page:
Recovered
[ 3786.042128] mce: Uncorrected hardware memory error in user-access at
200c9742380
[ 3786.042259] Memory failure: 0x200c9742: recovery action for dax page:
Recovered
[ 3786.464293] mce: Uncorrected hardware memory error in user-access at
200c9742380
[ 3786.464423] Memory failure: 0x200c9742: recovery action for dax page:
Recovered
[ 3786.818090] mce: Uncorrected hardware memory error in user-access at
200c9742380
[ 3786.818217] Memory failure: 0x200c9742: recovery action for dax page:
Recovered
[ 3787.085297] mce: Uncorrected hardware memory error in user-access at
200c9742380
[ 3787.085424] Memory failure: 0x200c9742: recovery action for dax page:
Recovered

It took us several weeks to pinpoint this problem,  but we eventually
used bpftrace to trace the page fault and mce address and successfully
identified the issue.


Joao added:

; Likely we never reproduce in production because we always pin
: device-dax regions in the region align they provide (Qemu does
: similarly with prealloc in hugetlb/file backed memory).  I think this
: bug requires that we touch *unpinned* device-dax regions unaligned to
: the device-dax selected alignment (page size i.e.  4K/2M/1G)

Link: https://lkml.kernel.org/r/23c02a03e8d666fef11bbe13e85c69c8b4ca0624.1727421694.git.llfl@linux.alibaba.com
Fixes: b9b5777f09be ("device-dax: use ALIGN() for determining pgoff")
Signed-off-by: Kun(llfl) &lt;llfl@linux.alibaba.com&gt;
Tested-by: JianXiong Zhao &lt;zhaojianxiong.zjx@alibaba-inc.com&gt;
Reviewed-by: Joao Martins &lt;joao.m.martins@oracle.com&gt;
Cc: Dan Williams &lt;dan.j.williams@intel.com&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>Merge tag 'driver-core-6.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core</title>
<updated>2024-07-25T17:42:22Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2024-07-25T17:42:22Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=c2a96b7f187fb6a455836d4a6e113947ff11de97'/>
<id>urn:sha1:c2a96b7f187fb6a455836d4a6e113947ff11de97</id>
<content type='text'>
Pull driver core updates from Greg KH:
 "Here is the big set of driver core changes for 6.11-rc1.

  Lots of stuff in here, with not a huge diffstat, but apis are evolving
  which required lots of files to be touched. Highlights of the changes
  in here are:

   - platform remove callback api final fixups (Uwe took many releases
     to get here, finally!)

   - Rust bindings for basic firmware apis and initial driver-core
     interactions.

     It's not all that useful for a "write a whole driver in rust" type
     of thing, but the firmware bindings do help out the phy rust
     drivers, and the driver core bindings give a solid base on which
     others can start their work.

     There is still a long way to go here before we have a multitude of
     rust drivers being added, but it's a great first step.

   - driver core const api changes.

     This reached across all bus types, and there are some fix-ups for
     some not-common bus types that linux-next and 0-day testing shook
     out.

     This work is being done to help make the rust bindings more safe,
     as well as the C code, moving toward the end-goal of allowing us to
     put driver structures into read-only memory. We aren't there yet,
     but are getting closer.

   - minor devres cleanups and fixes found by code inspection

   - arch_topology minor changes

   - other minor driver core cleanups

  All of these have been in linux-next for a very long time with no
  reported problems"

* tag 'driver-core-6.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (55 commits)
  ARM: sa1100: make match function take a const pointer
  sysfs/cpu: Make crash_hotplug attribute world-readable
  dio: Have dio_bus_match() callback take a const *
  zorro: make match function take a const pointer
  driver core: module: make module_[add|remove]_driver take a const *
  driver core: make driver_find_device() take a const *
  driver core: make driver_[create|remove]_file take a const *
  firmware_loader: fix soundness issue in `request_internal`
  firmware_loader: annotate doctests as `no_run`
  devres: Correct code style for functions that return a pointer type
  devres: Initialize an uninitialized struct member
  devres: Fix memory leakage caused by driver API devm_free_percpu()
  devres: Fix devm_krealloc() wasting memory
  driver core: platform: Switch to use kmemdup_array()
  driver core: have match() callback in struct bus_type take a const *
  MAINTAINERS: add Rust device abstractions to DRIVER CORE
  device: rust: improve safety comments
  MAINTAINERS: add Danilo as FIRMWARE LOADER maintainer
  MAINTAINERS: add Rust FW abstractions to FIRMWARE LOADER
  firmware: rust: improve safety comments
  ...
</content>
</entry>
<entry>
<title>driver core: have match() callback in struct bus_type take a const *</title>
<updated>2024-07-03T13:16:54Z</updated>
<author>
<name>Greg Kroah-Hartman</name>
<email>gregkh@linuxfoundation.org</email>
</author>
<published>2024-07-01T12:07:37Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=d69d804845985c29ab5be5a4b3b1f4787893daf8'/>
<id>urn:sha1:d69d804845985c29ab5be5a4b3b1f4787893daf8</id>
<content type='text'>
In the match() callback, the struct device_driver * should not be
changed, so change the function callback to be a const *.  This is one
step of many towards making the driver core safe to have struct
device_driver in read-only memory.

Because the match() callback is in all busses, all busses are modified
to handle this properly.  This does entail switching some container_of()
calls to container_of_const() to properly handle the constant *.

For some busses, like PCI and USB and HV, the const * is cast away in
the match callback as those busses do want to modify those structures at
this point in time (they have a local lock in the driver structure.)
That will have to be changed in the future if they wish to have their
struct device * in read-only-memory.

Cc: Rafael J. Wysocki &lt;rafael@kernel.org&gt;
Reviewed-by: Alex Elder &lt;elder@kernel.org&gt;
Acked-by: Sumit Garg &lt;sumit.garg@linaro.org&gt;
Link: https://lore.kernel.org/r/2024070136-wrongdoer-busily-01e8@gregkh
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>dax: add missing MODULE_DESCRIPTION() macros</title>
<updated>2024-06-17T23:42:16Z</updated>
<author>
<name>Jeff Johnson</name>
<email>quic_jjohnson@quicinc.com</email>
</author>
<published>2024-06-05T17:49:24Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=1d5198dd08ac04b13a8b7539131baf0980998032'/>
<id>urn:sha1:1d5198dd08ac04b13a8b7539131baf0980998032</id>
<content type='text'>
make allmodconfig &amp;&amp; make W=1 C=1 reports:
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/dax/hmem/dax_hmem.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/dax/device_dax.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/dax/kmem.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/dax/dax_pmem.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/dax/dax_cxl.o

Add all missing invocations of the MODULE_DESCRIPTION() macro.

[iweiny: edit descriptions]

Signed-off-by: Jeff Johnson &lt;quic_jjohnson@quicinc.com&gt;
Link: https://patch.msgid.link/r/20240605-md-drivers-dax-v1-1-3d448f3368b4@quicinc.com
Signed-off-by: Ira Weiny &lt;ira.weiny@intel.com&gt;
</content>
</entry>
<entry>
<title>Merge tag 'mm-stable-2024-05-17-19-19' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm</title>
<updated>2024-05-19T16:21:03Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2024-05-19T16:21:03Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=61307b7be41a1f1039d1d1368810a1d92cb97b44'/>
<id>urn:sha1:61307b7be41a1f1039d1d1368810a1d92cb97b44</id>
<content type='text'>
Pull mm updates from Andrew Morton:
 "The usual shower of singleton fixes and minor series all over MM,
  documented (hopefully adequately) in the respective changelogs.
  Notable series include:

   - Lucas Stach has provided some page-mapping cleanup/consolidation/
     maintainability work in the series "mm/treewide: Remove pXd_huge()
     API".

   - In the series "Allow migrate on protnone reference with
     MPOL_PREFERRED_MANY policy", Donet Tom has optimized mempolicy's
     MPOL_PREFERRED_MANY mode, yielding almost doubled performance in
     one test.

   - In their series "Memory allocation profiling" Kent Overstreet and
     Suren Baghdasaryan have contributed a means of determining (via
     /proc/allocinfo) whereabouts in the kernel memory is being
     allocated: number of calls and amount of memory.

   - Matthew Wilcox has provided the series "Various significant MM
     patches" which does a number of rather unrelated things, but in
     largely similar code sites.

   - In his series "mm: page_alloc: freelist migratetype hygiene"
     Johannes Weiner has fixed the page allocator's handling of
     migratetype requests, with resulting improvements in compaction
     efficiency.

   - In the series "make the hugetlb migration strategy consistent"
     Baolin Wang has fixed a hugetlb migration issue, which should
     improve hugetlb allocation reliability.

   - Liu Shixin has hit an I/O meltdown caused by readahead in a
     memory-tight memcg. Addressed in the series "Fix I/O high when
     memory almost met memcg limit".

   - In the series "mm/filemap: optimize folio adding and splitting"
     Kairui Song has optimized pagecache insertion, yielding ~10%
     performance improvement in one test.

   - Baoquan He has cleaned up and consolidated the early zone
     initialization code in the series "mm/mm_init.c: refactor
     free_area_init_core()".

   - Baoquan has also redone some MM initializatio code in the series
     "mm/init: minor clean up and improvement".

   - MM helper cleanups from Christoph Hellwig in his series "remove
     follow_pfn".

   - More cleanups from Matthew Wilcox in the series "Various
     page-&gt;flags cleanups".

   - Vlastimil Babka has contributed maintainability improvements in the
     series "memcg_kmem hooks refactoring".

   - More folio conversions and cleanups in Matthew Wilcox's series:
	"Convert huge_zero_page to huge_zero_folio"
	"khugepaged folio conversions"
	"Remove page_idle and page_young wrappers"
	"Use folio APIs in procfs"
	"Clean up __folio_put()"
	"Some cleanups for memory-failure"
	"Remove page_mapping()"
	"More folio compat code removal"

   - David Hildenbrand chipped in with "fs/proc/task_mmu: convert
     hugetlb functions to work on folis".

   - Code consolidation and cleanup work related to GUP's handling of
     hugetlbs in Peter Xu's series "mm/gup: Unify hugetlb, part 2".

   - Rick Edgecombe has developed some fixes to stack guard gaps in the
     series "Cover a guard gap corner case".

   - Jinjiang Tu has fixed KSM's behaviour after a fork+exec in the
     series "mm/ksm: fix ksm exec support for prctl".

   - Baolin Wang has implemented NUMA balancing for multi-size THPs.
     This is a simple first-cut implementation for now. The series is
     "support multi-size THP numa balancing".

   - Cleanups to vma handling helper functions from Matthew Wilcox in
     the series "Unify vma_address and vma_pgoff_address".

   - Some selftests maintenance work from Dev Jain in the series
     "selftests/mm: mremap_test: Optimizations and style fixes".

   - Improvements to the swapping of multi-size THPs from Ryan Roberts
     in the series "Swap-out mTHP without splitting".

   - Kefeng Wang has significantly optimized the handling of arm64's
     permission page faults in the series
	"arch/mm/fault: accelerate pagefault when badaccess"
	"mm: remove arch's private VM_FAULT_BADMAP/BADACCESS"

   - GUP cleanups from David Hildenbrand in "mm/gup: consistently call
     it GUP-fast".

   - hugetlb fault code cleanups from Vishal Moola in "Hugetlb fault
     path to use struct vm_fault".

   - selftests build fixes from John Hubbard in the series "Fix
     selftests/mm build without requiring "make headers"".

   - Memory tiering fixes/improvements from Ho-Ren (Jack) Chuang in the
     series "Improved Memory Tier Creation for CPUless NUMA Nodes".
     Fixes the initialization code so that migration between different
     memory types works as intended.

   - David Hildenbrand has improved follow_pte() and fixed an errant
     driver in the series "mm: follow_pte() improvements and acrn
     follow_pte() fixes".

   - David also did some cleanup work on large folio mapcounts in his
     series "mm: mapcount for large folios + page_mapcount() cleanups".

   - Folio conversions in KSM in Alex Shi's series "transfer page to
     folio in KSM".

   - Barry Song has added some sysfs stats for monitoring multi-size
     THP's in the series "mm: add per-order mTHP alloc and swpout
     counters".

   - Some zswap cleanups from Yosry Ahmed in the series "zswap
     same-filled and limit checking cleanups".

   - Matthew Wilcox has been looking at buffer_head code and found the
     documentation to be lacking. The series is "Improve buffer head
     documentation".

   - Multi-size THPs get more work, this time from Lance Yang. His
     series "mm/madvise: enhance lazyfreeing with mTHP in madvise_free"
     optimizes the freeing of these things.

   - Kemeng Shi has added more userspace-visible writeback
     instrumentation in the series "Improve visibility of writeback".

   - Kemeng Shi then sent some maintenance work on top in the series
     "Fix and cleanups to page-writeback".

   - Matthew Wilcox reduces mmap_lock traffic in the anon vma code in
     the series "Improve anon_vma scalability for anon VMAs". Intel's
     test bot reported an improbable 3x improvement in one test.

   - SeongJae Park adds some DAMON feature work in the series
	"mm/damon: add a DAMOS filter type for page granularity access recheck"
	"selftests/damon: add DAMOS quota goal test"

   - Also some maintenance work in the series
	"mm/damon/paddr: simplify page level access re-check for pageout"
	"mm/damon: misc fixes and improvements"

   - David Hildenbrand has disabled some known-to-fail selftests ni the
     series "selftests: mm: cow: flag vmsplice() hugetlb tests as
     XFAIL".

   - memcg metadata storage optimizations from Shakeel Butt in "memcg:
     reduce memory consumption by memcg stats".

   - DAX fixes and maintenance work from Vishal Verma in the series
     "dax/bus.c: Fixups for dax-bus locking""

* tag 'mm-stable-2024-05-17-19-19' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (426 commits)
  memcg, oom: cleanup unused memcg_oom_gfp_mask and memcg_oom_order
  selftests/mm: hugetlb_madv_vs_map: avoid test skipping by querying hugepage size at runtime
  mm/hugetlb: add missing VM_FAULT_SET_HINDEX in hugetlb_wp
  mm/hugetlb: add missing VM_FAULT_SET_HINDEX in hugetlb_fault
  selftests: cgroup: add tests to verify the zswap writeback path
  mm: memcg: make alloc_mem_cgroup_per_node_info() return bool
  mm/damon/core: fix return value from damos_wmark_metric_value
  mm: do not update memcg stats for NR_{FILE/SHMEM}_PMDMAPPED
  selftests: cgroup: remove redundant enabling of memory controller
  Docs/mm/damon/maintainer-profile: allow posting patches based on damon/next tree
  Docs/mm/damon/maintainer-profile: change the maintainer's timezone from PST to PT
  Docs/mm/damon/design: use a list for supported filters
  Docs/admin-guide/mm/damon/usage: fix wrong schemes effective quota update command
  Docs/admin-guide/mm/damon/usage: fix wrong example of DAMOS filter matching sysfs file
  selftests/damon: classify tests for functionalities and regressions
  selftests/damon/_damon_sysfs: use 'is' instead of '==' for 'None'
  selftests/damon/_damon_sysfs: find sysfs mount point from /proc/mounts
  selftests/damon/_damon_sysfs: check errors from nr_schemes file reads
  mm/damon/core: initialize -&gt;esz_bp from damos_quota_init_priv()
  selftests/damon: add a test for DAMOS quota goal
  ...
</content>
</entry>
<entry>
<title>Merge tag 'libnvdimm-for-6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm</title>
<updated>2024-05-15T21:28:56Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2024-05-15T21:28:56Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=c405aa3ea36c1f973a9f10bbcfabc9aeeb38040c'/>
<id>urn:sha1:c405aa3ea36c1f973a9f10bbcfabc9aeeb38040c</id>
<content type='text'>
Pull nvdimm updates from Ira Weiny:
 "The changes include removing duplicate code and updating the nvdimm
  tree to the current kernel interfaces such as using const for struct
  device_type and changing the platform remove callback signature"

* tag 'libnvdimm-for-6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  dax: remove redundant assignment to variable rc
  ndtest: Convert to platform remove callback returning void
  nvdimm/btt: always set max_integrity_segments
  nvdimm: remove nd_integrity_init
  dax: constify the struct device_type usage
  powerpc/papr_scm: Move duplicate definitions to common header files
</content>
</entry>
<entry>
<title>dax/bus.c: use the right locking mode (read vs write) in size_show</title>
<updated>2024-05-07T17:37:01Z</updated>
<author>
<name>Vishal Verma</name>
<email>vishal.l.verma@intel.com</email>
</author>
<published>2024-04-30T17:44:26Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=2acf04532d6d655d8c3b2ee4ddeb320107043086'/>
<id>urn:sha1:2acf04532d6d655d8c3b2ee4ddeb320107043086</id>
<content type='text'>
In size_show(), the dax_dev_rwsem only needs a read lock, but was
acquiring a write lock.  Change it to down_read_interruptible() so it
doesn't unnecessarily hold a write lock.

Link: https://lkml.kernel.org/r/20240430-vv-dax_abi_fixes-v3-4-e3dcd755774c@intel.com
Fixes: c05ae9d85b47 ("dax/bus.c: replace driver-core lock usage by a local rwsem")
Signed-off-by: Vishal Verma &lt;vishal.l.verma@intel.com&gt;
Reviewed-by: Dan Williams &lt;dan.j.williams@intel.com&gt;
Cc: Alison Schofield &lt;alison.schofield@intel.com&gt;
Cc: Dave Jiang &lt;dave.jiang@intel.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>dax/bus.c: don't use down_write_killable for non-user processes</title>
<updated>2024-05-07T17:37:01Z</updated>
<author>
<name>Vishal Verma</name>
<email>vishal.l.verma@intel.com</email>
</author>
<published>2024-04-30T17:44:25Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=e39dbcfba714c4c2e924e96fc8fdde1080a5a737'/>
<id>urn:sha1:e39dbcfba714c4c2e924e96fc8fdde1080a5a737</id>
<content type='text'>
Change an instance of down_write_killable() to a simple down_write() where
there is no user process that might want to interrupt the operation.

Link: https://lkml.kernel.org/r/20240430-vv-dax_abi_fixes-v3-3-e3dcd755774c@intel.com
Fixes: c05ae9d85b47 ("dax/bus.c: replace driver-core lock usage by a local rwsem")
Signed-off-by: Vishal Verma &lt;vishal.l.verma@intel.com&gt;
Reported-by: Dan Williams &lt;dan.j.williams@intel.com&gt;
Reviewed-by: Dan Williams &lt;dan.j.williams@intel.com&gt;
Cc: Alison Schofield &lt;alison.schofield@intel.com&gt;
Cc: Dave Jiang &lt;dave.jiang@intel.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>dax/bus.c: fix locking for unregister_dax_dev / unregister_dax_mapping paths</title>
<updated>2024-05-07T17:37:00Z</updated>
<author>
<name>Vishal Verma</name>
<email>vishal.l.verma@intel.com</email>
</author>
<published>2024-04-30T17:44:24Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=6f6544f27e41f9d7dca55c288f12175a9c48dfe2'/>
<id>urn:sha1:6f6544f27e41f9d7dca55c288f12175a9c48dfe2</id>
<content type='text'>
Commit c05ae9d85b47 ("dax/bus.c: replace driver-core lock usage by a local
rwsem") aimed to undo device_lock() abuses for protecting changes to
dax-driver internal data-structures like the dax_region resource tree to
device-dax-instance range structures.  However, the device_lock() was
legitimately enforcing that devices to be deleted were not current
actively attached to any driver nor assigned any capacity from the region.

As a result of the device_lock restoration in delete_store(), the
conditional locking in unregister_dev_dax() and unregister_dax_mapping()
can be removed.

Link: https://lkml.kernel.org/r/20240430-vv-dax_abi_fixes-v3-2-e3dcd755774c@intel.com
Fixes: c05ae9d85b47 ("dax/bus.c: replace driver-core lock usage by a local rwsem")
Signed-off-by: Vishal Verma &lt;vishal.l.verma@intel.com&gt;
Reported-by: Dan Williams &lt;dan.j.williams@intel.com&gt;
Reviewed-by: Dan Williams &lt;dan.j.williams@intel.com&gt;
Cc: Alison Schofield &lt;alison.schofield@intel.com&gt;
Cc: Dave Jiang &lt;dave.jiang@intel.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>dax/bus.c: replace WARN_ON_ONCE() with lockdep asserts</title>
<updated>2024-05-07T17:37:00Z</updated>
<author>
<name>Vishal Verma</name>
<email>vishal.l.verma@intel.com</email>
</author>
<published>2024-04-30T17:44:23Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=c14c647bbe23fd96f6bffcc122b9c6c8c46c7928'/>
<id>urn:sha1:c14c647bbe23fd96f6bffcc122b9c6c8c46c7928</id>
<content type='text'>
Patch series "dax/bus.c: Fixups for dax-bus locking", v3.

Commit Fixes: c05ae9d85b47 ("dax/bus.c: replace driver-core lock usage by
a local rwsem") introduced a few problems that this series aims to fix. 
Add back device_lock() where it was correctly used (during device
manipulation operations), remove conditional locking in
unregister_dax_dev() and unregister_dax_mapping(), use non-interruptible
versions of rwsem locks when not called from a user process, and fix up a
write vs.  read usage of an rwsem.


This patch (of 4):

In [1], Dan points out that all of the WARN_ON_ONCE() usage in the
referenced patch should be replaced with lockdep_assert_held, or
lockdep_held_assert_write().  Replace these as appropriate.

Link: https://lkml.kernel.org/r/20240430-vv-dax_abi_fixes-v3-0-e3dcd755774c@intel.com
Link: https://lore.kernel.org/r/65f0b5ef41817_aa222941a@dwillia2-mobl3.amr.corp.intel.com.notmuch [1]
Link: https://lkml.kernel.org/r/20240430-vv-dax_abi_fixes-v3-1-e3dcd755774c@intel.com
Fixes: c05ae9d85b47 ("dax/bus.c: replace driver-core lock usage by a local rwsem")
Signed-off-by: Vishal Verma &lt;vishal.l.verma@intel.com&gt;
Reported-by: Dan Williams &lt;dan.j.williams@intel.com&gt;
Reviewed-by: Dan Williams &lt;dan.j.williams@intel.com&gt;
Cc: Alison Schofield &lt;alison.schofield@intel.com&gt;
Cc: Dave Jiang &lt;dave.jiang@intel.com&gt;
Cc: Vishal Verma &lt;vishal.l.verma@intel.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
</entry>
</feed>
