<feed xmlns='http://www.w3.org/2005/Atom'>
<title>kernel/drivers/s390/block/dcssblk.c, branch linux-6.9.y</title>
<subtitle>Hosts the 0x221E linux distro kernel.</subtitle>
<id>https://universe.0xinfinity.dev/distro/kernel/atom?h=linux-6.9.y</id>
<link rel='self' href='https://universe.0xinfinity.dev/distro/kernel/atom?h=linux-6.9.y'/>
<link rel='alternate' type='text/html' href='https://universe.0xinfinity.dev/distro/kernel/'/>
<updated>2024-03-19T18:38:27Z</updated>
<entry>
<title>Merge tag 's390-6.9-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux</title>
<updated>2024-03-19T18:38:27Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2024-03-19T18:38:27Z</published>
<link rel='alternate' type='text/html' href='https://universe.0xinfinity.dev/distro/kernel/commit/?id=f9c035492f2010e1e7aede1f1bd32181d7cef2dc'/>
<id>urn:sha1:f9c035492f2010e1e7aede1f1bd32181d7cef2dc</id>
<content type='text'>
Pull more s390 updates from Heiko Carstens:

 - Various virtual vs physical address usage fixes

 - Add new bitwise types and helper functions and use them in s390
   specific drivers and code to make it easier to find virtual vs
   physical address usage bugs.

   Right now virtual and physical addresses are identical for s390,
   except for module, vmalloc, and similar areas. This will be changed,
   hopefully with the next merge window, so that e.g. the kernel image
   and modules will be located close to each other, allowing for direct
   branches and also for some other simplifications.

   As a prerequisite this requires to fix all misuses of virtual and
   physical addresses. As it turned out people are so used to the
   concept that virtual and physical addresses are the same, that new
   bugs got added to code which was already fixed. In order to avoid
   that even more code gets merged which adds such bugs add and use new
   bitwise types, so that sparse can be used to find such usage bugs.

   Most likely the new types can go away again after some time

 - Provide a simple ARCH_HAS_DEBUG_VIRTUAL implementation

 - Fix kprobe branch handling: if an out-of-line single stepped relative
   branch instruction has a target address within a certain address area
   in the entry code, the program check handler may incorrectly execute
   cleanup code as if KVM code was executed, leading to crashes

 - Fix reference counting of zcrypt card objects

 - Various other small fixes and cleanups

* tag 's390-6.9-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (41 commits)
  s390/entry: compare gmap asce to determine guest/host fault
  s390/entry: remove OUTSIDE macro
  s390/entry: add CIF_SIE flag and remove sie64a() address check
  s390/cio: use while (i--) pattern to clean up
  s390/raw3270: make class3270 constant
  s390/raw3270: improve raw3270_init() readability
  s390/tape: make tape_class constant
  s390/vmlogrdr: make vmlogrdr_class constant
  s390/vmur: make vmur_class constant
  s390/zcrypt: make zcrypt_class constant
  s390/mm: provide simple ARCH_HAS_DEBUG_VIRTUAL support
  s390/vfio_ccw_cp: use new address translation helpers
  s390/iucv: use new address translation helpers
  s390/ctcm: use new address translation helpers
  s390/lcs: use new address translation helpers
  s390/qeth: use new address translation helpers
  s390/zfcp: use new address translation helpers
  s390/tape: fix virtual vs physical address confusion
  s390/3270: use new address translation helpers
  s390/3215: use new address translation helpers
  ...
</content>
</entry>
<entry>
<title>Merge tag 'mm-stable-2024-03-13-20-04' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm</title>
<updated>2024-03-15T00:43:30Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2024-03-15T00:43:30Z</published>
<link rel='alternate' type='text/html' href='https://universe.0xinfinity.dev/distro/kernel/commit/?id=902861e34c401696ed9ad17a54c8790e7e8e3069'/>
<id>urn:sha1:902861e34c401696ed9ad17a54c8790e7e8e3069</id>
<content type='text'>
Pull MM updates from Andrew Morton:

 - Sumanth Korikkar has taught s390 to allocate hotplug-time page frames
   from hotplugged memory rather than only from main memory. Series
   "implement "memmap on memory" feature on s390".

 - More folio conversions from Matthew Wilcox in the series

	"Convert memcontrol charge moving to use folios"
	"mm: convert mm counter to take a folio"

 - Chengming Zhou has optimized zswap's rbtree locking, providing
   significant reductions in system time and modest but measurable
   reductions in overall runtimes. The series is "mm/zswap: optimize the
   scalability of zswap rb-tree".

 - Chengming Zhou has also provided the series "mm/zswap: optimize zswap
   lru list" which provides measurable runtime benefits in some
   swap-intensive situations.

 - And Chengming Zhou further optimizes zswap in the series "mm/zswap:
   optimize for dynamic zswap_pools". Measured improvements are modest.

 - zswap cleanups and simplifications from Yosry Ahmed in the series
   "mm: zswap: simplify zswap_swapoff()".

 - In the series "Add DAX ABI for memmap_on_memory", Vishal Verma has
   contributed several DAX cleanups as well as adding a sysfs tunable to
   control the memmap_on_memory setting when the dax device is
   hotplugged as system memory.

 - Johannes Weiner has added the large series "mm: zswap: cleanups",
   which does that.

 - More DAMON work from SeongJae Park in the series

	"mm/damon: make DAMON debugfs interface deprecation unignorable"
	"selftests/damon: add more tests for core functionalities and corner cases"
	"Docs/mm/damon: misc readability improvements"
	"mm/damon: let DAMOS feeds and tame/auto-tune itself"

 - In the series "mm/mempolicy: weighted interleave mempolicy and sysfs
   extension" Rakie Kim has developed a new mempolicy interleaving
   policy wherein we allocate memory across nodes in a weighted fashion
   rather than uniformly. This is beneficial in heterogeneous memory
   environments appearing with CXL.

 - Christophe Leroy has contributed some cleanup and consolidation work
   against the ARM pagetable dumping code in the series "mm: ptdump:
   Refactor CONFIG_DEBUG_WX and check_wx_pages debugfs attribute".

 - Luis Chamberlain has added some additional xarray selftesting in the
   series "test_xarray: advanced API multi-index tests".

 - Muhammad Usama Anjum has reworked the selftest code to make its
   human-readable output conform to the TAP ("Test Anything Protocol")
   format. Amongst other things, this opens up the use of third-party
   tools to parse and process out selftesting results.

 - Ryan Roberts has added fork()-time PTE batching of THP ptes in the
   series "mm/memory: optimize fork() with PTE-mapped THP". Mainly
   targeted at arm64, this significantly speeds up fork() when the
   process has a large number of pte-mapped folios.

 - David Hildenbrand also gets in on the THP pte batching game in his
   series "mm/memory: optimize unmap/zap with PTE-mapped THP". It
   implements batching during munmap() and other pte teardown
   situations. The microbenchmark improvements are nice.

 - And in the series "Transparent Contiguous PTEs for User Mappings"
   Ryan Roberts further utilizes arm's pte's contiguous bit ("contpte
   mappings"). Kernel build times on arm64 improved nicely. Ryan's
   series "Address some contpte nits" provides some followup work.

 - In the series "mm/hugetlb: Restore the reservation" Breno Leitao has
   fixed an obscure hugetlb race which was causing unnecessary page
   faults. He has also added a reproducer under the selftest code.

 - In the series "selftests/mm: Output cleanups for the compaction
   test", Mark Brown did what the title claims.

 - Kinsey Ho has added the series "mm/mglru: code cleanup and
   refactoring".

 - Even more zswap material from Nhat Pham. The series "fix and extend
   zswap kselftests" does as claimed.

 - In the series "Introduce cpu_dcache_is_aliasing() to fix DAX
   regression" Mathieu Desnoyers has cleaned up and fixed rather a mess
   in our handling of DAX on archiecctures which have virtually aliasing
   data caches. The arm architecture is the main beneficiary.

 - Lokesh Gidra's series "per-vma locks in userfaultfd" provides
   dramatic improvements in worst-case mmap_lock hold times during
   certain userfaultfd operations.

 - Some page_owner enhancements and maintenance work from Oscar Salvador
   in his series

	"page_owner: print stacks and their outstanding allocations"
	"page_owner: Fixup and cleanup"

 - Uladzislau Rezki has contributed some vmalloc scalability
   improvements in his series "Mitigate a vmap lock contention". It
   realizes a 12x improvement for a certain microbenchmark.

 - Some kexec/crash cleanup work from Baoquan He in the series "Split
   crash out from kexec and clean up related config items".

 - Some zsmalloc maintenance work from Chengming Zhou in the series

	"mm/zsmalloc: fix and optimize objects/page migration"
	"mm/zsmalloc: some cleanup for get/set_zspage_mapping()"

 - Zi Yan has taught the MM to perform compaction on folios larger than
   order=0. This a step along the path to implementaton of the merging
   of large anonymous folios. The series is named "Enable &gt;0 order folio
   memory compaction".

 - Christoph Hellwig has done quite a lot of cleanup work in the
   pagecache writeback code in his series "convert write_cache_pages()
   to an iterator".

 - Some modest hugetlb cleanups and speedups in Vishal Moola's series
   "Handle hugetlb faults under the VMA lock".

 - Zi Yan has changed the page splitting code so we can split huge pages
   into sizes other than order-0 to better utilize large folios. The
   series is named "Split a folio to any lower order folios".

 - David Hildenbrand has contributed the series "mm: remove
   total_mapcount()", a cleanup.

 - Matthew Wilcox has sought to improve the performance of bulk memory
   freeing in his series "Rearrange batched folio freeing".

 - Gang Li's series "hugetlb: parallelize hugetlb page init on boot"
   provides large improvements in bootup times on large machines which
   are configured to use large numbers of hugetlb pages.

 - Matthew Wilcox's series "PageFlags cleanups" does that.

 - Qi Zheng's series "minor fixes and supplement for ptdesc" does that
   also. S390 is affected.

 - Cleanups to our pagemap utility functions from Peter Xu in his series
   "mm/treewide: Replace pXd_large() with pXd_leaf()".

 - Nico Pache has fixed a few things with our hugepage selftests in his
   series "selftests/mm: Improve Hugepage Test Handling in MM
   Selftests".

 - Also, of course, many singleton patches to many things. Please see
   the individual changelogs for details.

* tag 'mm-stable-2024-03-13-20-04' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (435 commits)
  mm/zswap: remove the memcpy if acomp is not sleepable
  crypto: introduce: acomp_is_async to expose if comp drivers might sleep
  memtest: use {READ,WRITE}_ONCE in memory scanning
  mm: prohibit the last subpage from reusing the entire large folio
  mm: recover pud_leaf() definitions in nopmd case
  selftests/mm: skip the hugetlb-madvise tests on unmet hugepage requirements
  selftests/mm: skip uffd hugetlb tests with insufficient hugepages
  selftests/mm: dont fail testsuite due to a lack of hugepages
  mm/huge_memory: skip invalid debugfs new_order input for folio split
  mm/huge_memory: check new folio order when split a folio
  mm, vmscan: retry kswapd's priority loop with cache_trim_mode off on failure
  mm: add an explicit smp_wmb() to UFFDIO_CONTINUE
  mm: fix list corruption in put_pages_list
  mm: remove folio from deferred split list before uncharging it
  filemap: avoid unnecessary major faults in filemap_fault()
  mm,page_owner: drop unnecessary check
  mm,page_owner: check for null stack_record before bumping its refcount
  mm: swap: fix race between free_swap_and_cache() and swapoff()
  mm/treewide: align up pXd_leaf() retval across archs
  mm/treewide: drop pXd_large()
  ...
</content>
</entry>
<entry>
<title>s390/dcssblk: fix virtual vs physical address confusion</title>
<updated>2024-03-13T08:23:45Z</updated>
<author>
<name>Gerald Schaefer</name>
<email>gerald.schaefer@linux.ibm.com</email>
</author>
<published>2024-03-07T11:27:02Z</published>
<link rel='alternate' type='text/html' href='https://universe.0xinfinity.dev/distro/kernel/commit/?id=9a349be3ca4d670f1279bb16139d55e902e70789'/>
<id>urn:sha1:9a349be3ca4d670f1279bb16139d55e902e70789</id>
<content type='text'>
Fix virtual vs physical address confusion. This does not fix a bug
since virtual and physical address spaces are currently the same.

dax_direct_access() should receive a virtual kernel address in kaddr.

Reviewed-by: Heiko Carstens &lt;hca@linux.ibm.com&gt;
Acked-by: Alexander Gordeev &lt;agordeev@linux.ibm.com&gt;
Signed-off-by: Gerald Schaefer &lt;gerald.schaefer@linux.ibm.com&gt;
Signed-off-by: Heiko Carstens &lt;hca@linux.ibm.com&gt;
</content>
</entry>
<entry>
<title>dcssblk: handle alloc_dax() -EOPNOTSUPP failure</title>
<updated>2024-02-22T23:27:19Z</updated>
<author>
<name>Mathieu Desnoyers</name>
<email>mathieu.desnoyers@efficios.com</email>
</author>
<published>2024-02-15T14:46:29Z</published>
<link rel='alternate' type='text/html' href='https://universe.0xinfinity.dev/distro/kernel/commit/?id=cf7fe690abbbe520034843b97423d35e0acf9bd8'/>
<id>urn:sha1:cf7fe690abbbe520034843b97423d35e0acf9bd8</id>
<content type='text'>
In preparation for checking whether the architecture has data cache
aliasing within alloc_dax(), modify the error handling of dcssblk
dcssblk_add_store() to handle alloc_dax() -EOPNOTSUPP failures.

Considering that s390 is not a data cache aliasing architecture,
and considering that DCSSBLK selects DAX, a return value of -EOPNOTSUPP
from alloc_dax() should make dcssblk_add_store() fail.

Link: https://lkml.kernel.org/r/20240215144633.96437-6-mathieu.desnoyers@efficios.com
Fixes: d92576f1167c ("dax: does not work correctly with virtual aliasing caches")
Signed-off-by: Mathieu Desnoyers &lt;mathieu.desnoyers@efficios.com&gt;
Reviewed-by: Dan Williams &lt;dan.j.williams@intel.com&gt;
Acked-by: Heiko Carstens &lt;hca@linux.ibm.com&gt;
Cc: Alasdair Kergon &lt;agk@redhat.com&gt;
Cc: Mike Snitzer &lt;snitzer@kernel.org&gt;
Cc: Mikulas Patocka &lt;mpatocka@redhat.com&gt;
Cc: Dan Williams &lt;dan.j.williams@intel.com&gt;
Cc: Vishal Verma &lt;vishal.l.verma@intel.com&gt;
Cc: Dave Jiang &lt;dave.jiang@intel.com&gt;
Cc: Matthew Wilcox &lt;willy@infradead.org&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: Russell King &lt;linux@armlinux.org.uk&gt;
Cc: Christoph Hellwig &lt;hch@lst.de&gt;
Cc: Dave Chinner &lt;david@fromorbit.com&gt;
Cc: kernel test robot &lt;lkp@intel.com&gt;
Cc: Michael Sclafani &lt;dm-devel@lists.linux.dev&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>dcssblk: pass queue_limits to blk_mq_alloc_disk</title>
<updated>2024-02-19T23:58:24Z</updated>
<author>
<name>Christoph Hellwig</name>
<email>hch@lst.de</email>
</author>
<published>2024-02-15T07:10:55Z</published>
<link rel='alternate' type='text/html' href='https://universe.0xinfinity.dev/distro/kernel/commit/?id=af190c53c995bf7c742c3387f6537534f8b92322'/>
<id>urn:sha1:af190c53c995bf7c742c3387f6537534f8b92322</id>
<content type='text'>
Pass the queue limits directly to blk_alloc_disk instead of setting them
one at a time.

Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Reviewed-by: Dan Williams &lt;dan.j.williams@intel.com&gt;
Reviewed-by: Himanshu Madhani &lt;himanshu.madhani@oracle.com&gt;
Link: https://lore.kernel.org/r/20240215071055.2201424-10-hch@lst.de
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</content>
</entry>
<entry>
<title>block: pass a queue_limits argument to blk_alloc_disk</title>
<updated>2024-02-19T23:58:23Z</updated>
<author>
<name>Christoph Hellwig</name>
<email>hch@lst.de</email>
</author>
<published>2024-02-15T07:10:47Z</published>
<link rel='alternate' type='text/html' href='https://universe.0xinfinity.dev/distro/kernel/commit/?id=74fa8f9c553f7b5ccab7d103acae63cc2e080465'/>
<id>urn:sha1:74fa8f9c553f7b5ccab7d103acae63cc2e080465</id>
<content type='text'>
Pass a queue_limits to blk_alloc_disk and apply it if non-NULL.  This
will allow allocating queues with valid queue limits instead of setting
the values one at a time later.

Also change blk_alloc_disk to return an ERR_PTR instead of just NULL
which can't distinguish errors.

Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Reviewed-by: Dan Williams &lt;dan.j.williams@intel.com&gt;
Reviewed-by: Himanshu Madhani &lt;himanshu.madhani@oracle.com&gt;
Link: https://lore.kernel.org/r/20240215071055.2201424-2-hch@lst.de
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</content>
</entry>
<entry>
<title>s390/dcssblk: fix lockdep warning</title>
<updated>2023-08-30T09:03:27Z</updated>
<author>
<name>Gerald Schaefer</name>
<email>gerald.schaefer@linux.ibm.com</email>
</author>
<published>2023-08-22T15:19:32Z</published>
<link rel='alternate' type='text/html' href='https://universe.0xinfinity.dev/distro/kernel/commit/?id=789dd8cb1eb1503c8167bf2ffc88f74a70245044'/>
<id>urn:sha1:789dd8cb1eb1503c8167bf2ffc88f74a70245044</id>
<content type='text'>
dcssblk_remove_store() holds the dcssblk_devices_sem semaphore while
calling del_gendisk(dev_info-&gt;gd), which in turn tries to acquire
disk-&gt;open_mutex. Then there is dcssblk_release(), which is called
with disk-&gt;open_mutex held, and tries to acquire dcssblk_devices_sem.

Lockdep reports this as possible circular locking dependency (CPU0 =
dcssblk_remove_store, CPU1 = dcssblk_release):

[   44.948865]  Possible unsafe locking scenario:

[   44.948866]        CPU0                    CPU1
[   44.948867]        ----                    ----
[   44.948868]   lock(&amp;dcssblk_devices_sem);
[   44.948870]                                lock(&amp;disk-&gt;open_mutex);
[   44.948872]                                lock(&amp;dcssblk_devices_sem);
[   44.948874]   lock(&amp;disk-&gt;open_mutex);
[   44.948876]
                *** DEADLOCK ***

In practice, this deadlock should not happen, since dcssblk_remove_store()
checks for dev_info-&gt;use_count != 0 after acquiring dcssblk_devices_sem,
and breaks out before calling del_gendisk(). dev_info-&gt;use_count will be
decremented in dcssblk_release(), protected by dcssblk_devices_sem.

Still there is no need for dcssblk_remove_store() to hold the
dcssblk_devices_sem until after calling del_gendisk(), as this only
protects dcssblk internal data. So fix the lockdep warning by releasing
dcssblk_devices_sem earlier. Also move the segment_unload() loop up,
similar to dcssblk_shared_store() error path, no need to do that after
calling del_gendisk().

Also change dcssblk_shared_store() error path, where dcssblk_devices_sem
was also released only after calling del_gendisk(), and a similar lockdep
warning could be triggered (but also deadlock prevented by check for
dev_info-&gt;use_count).

Acked-by: Heiko Carstens &lt;hca@linux.ibm.com&gt;
Signed-off-by: Gerald Schaefer &lt;gerald.schaefer@linux.ibm.com&gt;
Signed-off-by: Heiko Carstens &lt;hca@linux.ibm.com&gt;
</content>
</entry>
<entry>
<title>s390/dcssblk: fix kernel crash with list_add corruption</title>
<updated>2023-08-16T13:13:03Z</updated>
<author>
<name>Gerald Schaefer</name>
<email>gerald.schaefer@linux.ibm.com</email>
</author>
<published>2023-08-10T08:22:36Z</published>
<link rel='alternate' type='text/html' href='https://universe.0xinfinity.dev/distro/kernel/commit/?id=c8f40a0bccefd613748d080147469a4652d6e74c'/>
<id>urn:sha1:c8f40a0bccefd613748d080147469a4652d6e74c</id>
<content type='text'>
Commit fb08a1908cb1 ("dax: simplify the dax_device &lt;-&gt; gendisk
association") introduced new logic for gendisk association, requiring
drivers to explicitly call dax_add_host() and dax_remove_host().

For dcssblk driver, some dax_remove_host() calls were missing, e.g. in
device remove path. The commit also broke error handling for out_dax case
in device add path, resulting in an extra put_device() w/o the previous
get_device() in that case.

This lead to stale xarray entries after device add / remove cycles. In the
case when a previously used struct gendisk pointer (xarray index) would be
used again, because blk_alloc_disk() happened to return such a pointer, the
xa_insert() in dax_add_host() would fail and go to out_dax, doing the extra
put_device() in the error path. In combination with an already flawed error
handling in dcssblk (device_register() cleanup), which needs to be
addressed in a separate patch, this resulted in a missing device_del() /
klist_del(), and eventually in the kernel crash with list_add corruption on
a subsequent device_add() / klist_add().

Fix this by adding the missing dax_remove_host() calls, and also move the
put_device() in the error path to restore the previous logic.

Fixes: fb08a1908cb1 ("dax: simplify the dax_device &lt;-&gt; gendisk association")
Cc: &lt;stable@vger.kernel.org&gt; # 5.17+
Acked-by: Heiko Carstens &lt;hca@linux.ibm.com&gt;
Signed-off-by: Gerald Schaefer &lt;gerald.schaefer@linux.ibm.com&gt;
Signed-off-by: Heiko Carstens &lt;hca@linux.ibm.com&gt;
</content>
</entry>
<entry>
<title>s390/dcssblk: fix virtual vs physical address confusion</title>
<updated>2023-07-24T10:12:23Z</updated>
<author>
<name>Alexander Gordeev</name>
<email>agordeev@linux.ibm.com</email>
</author>
<published>2023-07-11T15:41:37Z</published>
<link rel='alternate' type='text/html' href='https://universe.0xinfinity.dev/distro/kernel/commit/?id=3b53d7b131bd79d97dd553af84846fde456e029f'/>
<id>urn:sha1:3b53d7b131bd79d97dd553af84846fde456e029f</id>
<content type='text'>
Fix virtual vs physical address confusion (which currently are the same).

Reviewed-by: Gerald Schaefer &lt;gerald.schaefer@linux.ibm.com&gt;
Signed-off-by: Alexander Gordeev &lt;agordeev@linux.ibm.com&gt;
Signed-off-by: Heiko Carstens &lt;hca@linux.ibm.com&gt;
</content>
</entry>
<entry>
<title>s390/dcssblk: use IS_ALIGNED() for alignment checks</title>
<updated>2023-07-24T10:12:23Z</updated>
<author>
<name>Alexander Gordeev</name>
<email>agordeev@linux.ibm.com</email>
</author>
<published>2023-07-11T15:59:42Z</published>
<link rel='alternate' type='text/html' href='https://universe.0xinfinity.dev/distro/kernel/commit/?id=04b8698ae879b88f96c083292f328bd31b555422'/>
<id>urn:sha1:04b8698ae879b88f96c083292f328bd31b555422</id>
<content type='text'>
Use IS_ALIGNED() instead of cumbersome bit manipulations.

Reviewed-by: Gerald Schaefer &lt;gerald.schaefer@linux.ibm.com&gt;
Signed-off-by: Alexander Gordeev &lt;agordeev@linux.ibm.com&gt;
Signed-off-by: Heiko Carstens &lt;hca@linux.ibm.com&gt;
</content>
</entry>
</feed>
