<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/arch/alpha/include/uapi, branch v6.1.168</title>
<subtitle>Clone of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git</subtitle>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/'/>
<entry>
<title>alpha: don't reference obsolete termio struct for TC* constants</title>
<updated>2026-01-17T15:39:28+00:00</updated>
<author>
<name>Sam James</name>
<email>sam@gentoo.org</email>
</author>
<published>2025-12-05T08:14:57+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=3af7369111c086b1b30dec7dbd657f945bc3fd65'/>
<id>3af7369111c086b1b30dec7dbd657f945bc3fd65</id>
<content type='text'>
[ Upstream commit 9aeed9041929812a10a6d693af050846942a1d16 ]

Similar in nature to ab107276607af90b13a5994997e19b7b9731e251. glibc-2.42
drops the legacy termio struct, but the ioctls.h header still defines some
TC* constants in terms of termio (via sizeof). Hardcode the values instead.

This fixes building Python for example, which falls over like:
  ./Modules/termios.c:1119:16: error: invalid application of 'sizeof' to incomplete type 'struct termio'

Link: https://bugs.gentoo.org/961769
Link: https://bugs.gentoo.org/962600
Signed-off-by: Sam James &lt;sam@gentoo.org&gt;
Reviewed-by: Magnus Lindholm &lt;linmag7@gmail.com&gt;
Link: https://lore.kernel.org/r/6ebd3451908785cad53b50ca6bc46cfe9d6bc03c.1764922497.git.sam@gentoo.org
Signed-off-by: Magnus Lindholm &lt;linmag7@gmail.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 9aeed9041929812a10a6d693af050846942a1d16 ]

Similar in nature to ab107276607af90b13a5994997e19b7b9731e251. glibc-2.42
drops the legacy termio struct, but the ioctls.h header still defines some
TC* constants in terms of termio (via sizeof). Hardcode the values instead.

This fixes building Python for example, which falls over like:
  ./Modules/termios.c:1119:16: error: invalid application of 'sizeof' to incomplete type 'struct termio'

Link: https://bugs.gentoo.org/961769
Link: https://bugs.gentoo.org/962600
Signed-off-by: Sam James &lt;sam@gentoo.org&gt;
Reviewed-by: Magnus Lindholm &lt;linmag7@gmail.com&gt;
Link: https://lore.kernel.org/r/6ebd3451908785cad53b50ca6bc46cfe9d6bc03c.1764922497.git.sam@gentoo.org
Signed-off-by: Magnus Lindholm &lt;linmag7@gmail.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>alpha: make stack 16-byte aligned (most cases)</title>
<updated>2025-02-21T12:50:04+00:00</updated>
<author>
<name>Ivan Kokshaysky</name>
<email>ink@unseen.parts</email>
</author>
<published>2025-02-04T22:35:23+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=17d24ff755a805271fdb2c2e90211706c8662cf5'/>
<id>17d24ff755a805271fdb2c2e90211706c8662cf5</id>
<content type='text'>
commit 0a0f7362b0367634a2d5cb7c96226afc116f19c9 upstream.

The problem is that GCC expects 16-byte alignment of the incoming stack
since early 2004, as Maciej found out [1]:
  Having actually dug speculatively I can see that the psABI was changed in
 GCC 3.5 with commit e5e10fb4a350 ("re PR target/14539 (128-bit long double
 improperly aligned)") back in Mar 2004, when the stack pointer alignment
 was increased from 8 bytes to 16 bytes, and arch/alpha/kernel/entry.S has
 various suspicious stack pointer adjustments, starting with SP_OFF which
 is not a whole multiple of 16.

Also, as Magnus noted, "ALPHA Calling Standard" [2] required the same:
 D.3.1 Stack Alignment
  This standard requires that stacks be octaword aligned at the time a
  new procedure is invoked.

However:
- the "normal" kernel stack is always misaligned by 8 bytes, thanks to
  the odd number of 64-bit words in 'struct pt_regs', which is the very
  first thing pushed onto the kernel thread stack;
- syscall, fault, interrupt etc. handlers may, or may not, receive aligned
  stack depending on numerous factors.

Somehow we got away with it until recently, when we ended up with
a stack corruption in kernel/smp.c:smp_call_function_single() due to
its use of 32-byte aligned local data and the compiler doing clever
things allocating it on the stack.

This adds padding between the PAL-saved and kernel-saved registers
so that 'struct pt_regs' have an even number of 64-bit words.
This makes the stack properly aligned for most of the kernel
code, except two handlers which need special threatment.

Note: struct pt_regs doesn't belong in uapi/asm; this should be fixed,
but let's put this off until later.

Link: https://lore.kernel.org/rcu/alpine.DEB.2.21.2501130248010.18889@angie.orcam.me.uk/ [1]
Link: https://bitsavers.org/pdf/dec/alpha/Alpha_Calling_Standard_Rev_2.0_19900427.pdf [2]

Cc: stable@vger.kernel.org
Tested-by: Maciej W. Rozycki &lt;macro@orcam.me.uk&gt;
Tested-by: Magnus Lindholm &lt;linmag7@gmail.com&gt;
Tested-by: Matt Turner &lt;mattst88@gmail.com&gt;
Reviewed-by: Maciej W. Rozycki &lt;macro@orcam.me.uk&gt;
Signed-off-by: Ivan Kokshaysky &lt;ink@unseen.parts&gt;
Signed-off-by: Matt Turner &lt;mattst88@gmail.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 0a0f7362b0367634a2d5cb7c96226afc116f19c9 upstream.

The problem is that GCC expects 16-byte alignment of the incoming stack
since early 2004, as Maciej found out [1]:
  Having actually dug speculatively I can see that the psABI was changed in
 GCC 3.5 with commit e5e10fb4a350 ("re PR target/14539 (128-bit long double
 improperly aligned)") back in Mar 2004, when the stack pointer alignment
 was increased from 8 bytes to 16 bytes, and arch/alpha/kernel/entry.S has
 various suspicious stack pointer adjustments, starting with SP_OFF which
 is not a whole multiple of 16.

Also, as Magnus noted, "ALPHA Calling Standard" [2] required the same:
 D.3.1 Stack Alignment
  This standard requires that stacks be octaword aligned at the time a
  new procedure is invoked.

However:
- the "normal" kernel stack is always misaligned by 8 bytes, thanks to
  the odd number of 64-bit words in 'struct pt_regs', which is the very
  first thing pushed onto the kernel thread stack;
- syscall, fault, interrupt etc. handlers may, or may not, receive aligned
  stack depending on numerous factors.

Somehow we got away with it until recently, when we ended up with
a stack corruption in kernel/smp.c:smp_call_function_single() due to
its use of 32-byte aligned local data and the compiler doing clever
things allocating it on the stack.

This adds padding between the PAL-saved and kernel-saved registers
so that 'struct pt_regs' have an even number of 64-bit words.
This makes the stack properly aligned for most of the kernel
code, except two handlers which need special threatment.

Note: struct pt_regs doesn't belong in uapi/asm; this should be fixed,
but let's put this off until later.

Link: https://lore.kernel.org/rcu/alpine.DEB.2.21.2501130248010.18889@angie.orcam.me.uk/ [1]
Link: https://bitsavers.org/pdf/dec/alpha/Alpha_Calling_Standard_Rev_2.0_19900427.pdf [2]

Cc: stable@vger.kernel.org
Tested-by: Maciej W. Rozycki &lt;macro@orcam.me.uk&gt;
Tested-by: Magnus Lindholm &lt;linmag7@gmail.com&gt;
Tested-by: Matt Turner &lt;mattst88@gmail.com&gt;
Reviewed-by: Maciej W. Rozycki &lt;macro@orcam.me.uk&gt;
Signed-off-by: Ivan Kokshaysky &lt;ink@unseen.parts&gt;
Signed-off-by: Matt Turner &lt;mattst88@gmail.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>mm/madvise: introduce MADV_COLLAPSE sync hugepage collapse</title>
<updated>2022-09-12T03:25:46+00:00</updated>
<author>
<name>Zach O'Keefe</name>
<email>zokeefe@google.com</email>
</author>
<published>2022-07-06T23:59:27+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=7d8faaf155454f8798ec56404faca29a82689c77'/>
<id>7d8faaf155454f8798ec56404faca29a82689c77</id>
<content type='text'>
This idea was introduced by David Rientjes[1].

Introduce a new madvise mode, MADV_COLLAPSE, that allows users to request
a synchronous collapse of memory at their own expense.

The benefits of this approach are:

* CPU is charged to the process that wants to spend the cycles for the
  THP
* Avoid unpredictable timing of khugepaged collapse

Semantics

This call is independent of the system-wide THP sysfs settings, but will
fail for memory marked VM_NOHUGEPAGE.  If the ranges provided span
multiple VMAs, the semantics of the collapse over each VMA is independent
from the others.  This implies a hugepage cannot cross a VMA boundary.  If
collapse of a given hugepage-aligned/sized region fails, the operation may
continue to attempt collapsing the remainder of memory specified.

The memory ranges provided must be page-aligned, but are not required to
be hugepage-aligned.  If the memory ranges are not hugepage-aligned, the
start/end of the range will be clamped to the first/last hugepage-aligned
address covered by said range.  The memory ranges must span at least one
hugepage-sized region.

All non-resident pages covered by the range will first be
swapped/faulted-in, before being internally copied onto a freshly
allocated hugepage.  Unmapped pages will have their data directly
initialized to 0 in the new hugepage.  However, for every eligible
hugepage aligned/sized region to-be collapsed, at least one page must
currently be backed by memory (a PMD covering the address range must
already exist).

Allocation for the new hugepage may enter direct reclaim and/or
compaction, regardless of VMA flags.  When the system has multiple NUMA
nodes, the hugepage will be allocated from the node providing the most
native pages.  This operation operates on the current state of the
specified process and makes no persistent changes or guarantees on how
pages will be mapped, constructed, or faulted in the future

Return Value

If all hugepage-sized/aligned regions covered by the provided range were
either successfully collapsed, or were already PMD-mapped THPs, this
operation will be deemed successful.  On success, process_madvise(2)
returns the number of bytes advised, and madvise(2) returns 0.  Else, -1
is returned and errno is set to indicate the error for the most-recently
attempted hugepage collapse.  Note that many failures might have occurred,
since the operation may continue to collapse in the event a single
hugepage-sized/aligned region fails.

	ENOMEM	Memory allocation failed or VMA not found
	EBUSY	Memcg charging failed
	EAGAIN	Required resource temporarily unavailable.  Try again
		might succeed.
	EINVAL	Other error: No PMD found, subpage doesn't have Present
		bit set, "Special" page no backed by struct page, VMA
		incorrectly sized, address not page-aligned, ...

Most notable here is ENOMEM and EBUSY (new to madvise) which are intended
to provide the caller with actionable feedback so they may take an
appropriate fallback measure.

Use Cases

An immediate user of this new functionality are malloc() implementations
that manage memory in hugepage-sized chunks, but sometimes subrelease
memory back to the system in native-sized chunks via MADV_DONTNEED;
zapping the pmd.  Later, when the memory is hot, the implementation could
madvise(MADV_COLLAPSE) to re-back the memory by THPs to regain hugepage
coverage and dTLB performance.  TCMalloc is such an implementation that
could benefit from this[2].

Only privately-mapped anon memory is supported for now, but additional
support for file, shmem, and HugeTLB high-granularity mappings[2] is
expected.  File and tmpfs/shmem support would permit:

* Backing executable text by THPs.  Current support provided by
  CONFIG_READ_ONLY_THP_FOR_FS may take a long time on a large system which
  might impair services from serving at their full rated load after
  (re)starting.  Tricks like mremap(2)'ing text onto anonymous memory to
  immediately realize iTLB performance prevents page sharing and demand
  paging, both of which increase steady state memory footprint.  With
  MADV_COLLAPSE, we get the best of both worlds: Peak upfront performance
  and lower RAM footprints.
* Backing guest memory by hugapages after the memory contents have been
  migrated in native-page-sized chunks to a new host, in a
  userfaultfd-based live-migration stack.

[1] https://lore.kernel.org/linux-mm/d098c392-273a-36a4-1a29-59731cdf5d3d@google.com/
[2] https://github.com/google/tcmalloc/tree/master/tcmalloc

[jrdr.linux@gmail.com: avoid possible memory leak in failure path]
  Link: https://lkml.kernel.org/r/20220713024109.62810-1-jrdr.linux@gmail.com
[zokeefe@google.com add missing kfree() to madvise_collapse()]
  Link: https://lore.kernel.org/linux-mm/20220713024109.62810-1-jrdr.linux@gmail.com/
  Link: https://lkml.kernel.org/r/20220713161851.1879439-1-zokeefe@google.com
[zokeefe@google.com: delay computation of hpage boundaries until use]]
  Link: https://lkml.kernel.org/r/20220720140603.1958773-4-zokeefe@google.com
Link: https://lkml.kernel.org/r/20220706235936.2197195-10-zokeefe@google.com
Signed-off-by: Zach O'Keefe &lt;zokeefe@google.com&gt;
Signed-off-by: "Souptick Joarder (HPE)" &lt;jrdr.linux@gmail.com&gt;
Suggested-by: David Rientjes &lt;rientjes@google.com&gt;
Cc: Alex Shi &lt;alex.shi@linux.alibaba.com&gt;
Cc: Andrea Arcangeli &lt;aarcange@redhat.com&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: Axel Rasmussen &lt;axelrasmussen@google.com&gt;
Cc: Chris Kennelly &lt;ckennelly@google.com&gt;
Cc: Chris Zankel &lt;chris@zankel.net&gt;
Cc: David Hildenbrand &lt;david@redhat.com&gt;
Cc: Helge Deller &lt;deller@gmx.de&gt;
Cc: Hugh Dickins &lt;hughd@google.com&gt;
Cc: Ivan Kokshaysky &lt;ink@jurassic.park.msu.ru&gt;
Cc: James Bottomley &lt;James.Bottomley@HansenPartnership.com&gt;
Cc: Jens Axboe &lt;axboe@kernel.dk&gt;
Cc: "Kirill A. Shutemov" &lt;kirill.shutemov@linux.intel.com&gt;
Cc: Matthew Wilcox &lt;willy@infradead.org&gt;
Cc: Matt Turner &lt;mattst88@gmail.com&gt;
Cc: Max Filippov &lt;jcmvbkbc@gmail.com&gt;
Cc: Miaohe Lin &lt;linmiaohe@huawei.com&gt;
Cc: Michal Hocko &lt;mhocko@suse.com&gt;
Cc: Minchan Kim &lt;minchan@kernel.org&gt;
Cc: Pasha Tatashin &lt;pasha.tatashin@soleen.com&gt;
Cc: Pavel Begunkov &lt;asml.silence@gmail.com&gt;
Cc: Peter Xu &lt;peterx@redhat.com&gt;
Cc: Rongwei Wang &lt;rongwei.wang@linux.alibaba.com&gt;
Cc: SeongJae Park &lt;sj@kernel.org&gt;
Cc: Song Liu &lt;songliubraving@fb.com&gt;
Cc: Thomas Bogendoerfer &lt;tsbogend@alpha.franken.de&gt;
Cc: Vlastimil Babka &lt;vbabka@suse.cz&gt;
Cc: Yang Shi &lt;shy828301@gmail.com&gt;
Cc: Zi Yan &lt;ziy@nvidia.com&gt;
Cc: Dan Carpenter &lt;dan.carpenter@oracle.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This idea was introduced by David Rientjes[1].

Introduce a new madvise mode, MADV_COLLAPSE, that allows users to request
a synchronous collapse of memory at their own expense.

The benefits of this approach are:

* CPU is charged to the process that wants to spend the cycles for the
  THP
* Avoid unpredictable timing of khugepaged collapse

Semantics

This call is independent of the system-wide THP sysfs settings, but will
fail for memory marked VM_NOHUGEPAGE.  If the ranges provided span
multiple VMAs, the semantics of the collapse over each VMA is independent
from the others.  This implies a hugepage cannot cross a VMA boundary.  If
collapse of a given hugepage-aligned/sized region fails, the operation may
continue to attempt collapsing the remainder of memory specified.

The memory ranges provided must be page-aligned, but are not required to
be hugepage-aligned.  If the memory ranges are not hugepage-aligned, the
start/end of the range will be clamped to the first/last hugepage-aligned
address covered by said range.  The memory ranges must span at least one
hugepage-sized region.

All non-resident pages covered by the range will first be
swapped/faulted-in, before being internally copied onto a freshly
allocated hugepage.  Unmapped pages will have their data directly
initialized to 0 in the new hugepage.  However, for every eligible
hugepage aligned/sized region to-be collapsed, at least one page must
currently be backed by memory (a PMD covering the address range must
already exist).

Allocation for the new hugepage may enter direct reclaim and/or
compaction, regardless of VMA flags.  When the system has multiple NUMA
nodes, the hugepage will be allocated from the node providing the most
native pages.  This operation operates on the current state of the
specified process and makes no persistent changes or guarantees on how
pages will be mapped, constructed, or faulted in the future

Return Value

If all hugepage-sized/aligned regions covered by the provided range were
either successfully collapsed, or were already PMD-mapped THPs, this
operation will be deemed successful.  On success, process_madvise(2)
returns the number of bytes advised, and madvise(2) returns 0.  Else, -1
is returned and errno is set to indicate the error for the most-recently
attempted hugepage collapse.  Note that many failures might have occurred,
since the operation may continue to collapse in the event a single
hugepage-sized/aligned region fails.

	ENOMEM	Memory allocation failed or VMA not found
	EBUSY	Memcg charging failed
	EAGAIN	Required resource temporarily unavailable.  Try again
		might succeed.
	EINVAL	Other error: No PMD found, subpage doesn't have Present
		bit set, "Special" page no backed by struct page, VMA
		incorrectly sized, address not page-aligned, ...

Most notable here is ENOMEM and EBUSY (new to madvise) which are intended
to provide the caller with actionable feedback so they may take an
appropriate fallback measure.

Use Cases

An immediate user of this new functionality are malloc() implementations
that manage memory in hugepage-sized chunks, but sometimes subrelease
memory back to the system in native-sized chunks via MADV_DONTNEED;
zapping the pmd.  Later, when the memory is hot, the implementation could
madvise(MADV_COLLAPSE) to re-back the memory by THPs to regain hugepage
coverage and dTLB performance.  TCMalloc is such an implementation that
could benefit from this[2].

Only privately-mapped anon memory is supported for now, but additional
support for file, shmem, and HugeTLB high-granularity mappings[2] is
expected.  File and tmpfs/shmem support would permit:

* Backing executable text by THPs.  Current support provided by
  CONFIG_READ_ONLY_THP_FOR_FS may take a long time on a large system which
  might impair services from serving at their full rated load after
  (re)starting.  Tricks like mremap(2)'ing text onto anonymous memory to
  immediately realize iTLB performance prevents page sharing and demand
  paging, both of which increase steady state memory footprint.  With
  MADV_COLLAPSE, we get the best of both worlds: Peak upfront performance
  and lower RAM footprints.
* Backing guest memory by hugapages after the memory contents have been
  migrated in native-page-sized chunks to a new host, in a
  userfaultfd-based live-migration stack.

[1] https://lore.kernel.org/linux-mm/d098c392-273a-36a4-1a29-59731cdf5d3d@google.com/
[2] https://github.com/google/tcmalloc/tree/master/tcmalloc

[jrdr.linux@gmail.com: avoid possible memory leak in failure path]
  Link: https://lkml.kernel.org/r/20220713024109.62810-1-jrdr.linux@gmail.com
[zokeefe@google.com add missing kfree() to madvise_collapse()]
  Link: https://lore.kernel.org/linux-mm/20220713024109.62810-1-jrdr.linux@gmail.com/
  Link: https://lkml.kernel.org/r/20220713161851.1879439-1-zokeefe@google.com
[zokeefe@google.com: delay computation of hpage boundaries until use]]
  Link: https://lkml.kernel.org/r/20220720140603.1958773-4-zokeefe@google.com
Link: https://lkml.kernel.org/r/20220706235936.2197195-10-zokeefe@google.com
Signed-off-by: Zach O'Keefe &lt;zokeefe@google.com&gt;
Signed-off-by: "Souptick Joarder (HPE)" &lt;jrdr.linux@gmail.com&gt;
Suggested-by: David Rientjes &lt;rientjes@google.com&gt;
Cc: Alex Shi &lt;alex.shi@linux.alibaba.com&gt;
Cc: Andrea Arcangeli &lt;aarcange@redhat.com&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: Axel Rasmussen &lt;axelrasmussen@google.com&gt;
Cc: Chris Kennelly &lt;ckennelly@google.com&gt;
Cc: Chris Zankel &lt;chris@zankel.net&gt;
Cc: David Hildenbrand &lt;david@redhat.com&gt;
Cc: Helge Deller &lt;deller@gmx.de&gt;
Cc: Hugh Dickins &lt;hughd@google.com&gt;
Cc: Ivan Kokshaysky &lt;ink@jurassic.park.msu.ru&gt;
Cc: James Bottomley &lt;James.Bottomley@HansenPartnership.com&gt;
Cc: Jens Axboe &lt;axboe@kernel.dk&gt;
Cc: "Kirill A. Shutemov" &lt;kirill.shutemov@linux.intel.com&gt;
Cc: Matthew Wilcox &lt;willy@infradead.org&gt;
Cc: Matt Turner &lt;mattst88@gmail.com&gt;
Cc: Max Filippov &lt;jcmvbkbc@gmail.com&gt;
Cc: Miaohe Lin &lt;linmiaohe@huawei.com&gt;
Cc: Michal Hocko &lt;mhocko@suse.com&gt;
Cc: Minchan Kim &lt;minchan@kernel.org&gt;
Cc: Pasha Tatashin &lt;pasha.tatashin@soleen.com&gt;
Cc: Pavel Begunkov &lt;asml.silence@gmail.com&gt;
Cc: Peter Xu &lt;peterx@redhat.com&gt;
Cc: Rongwei Wang &lt;rongwei.wang@linux.alibaba.com&gt;
Cc: SeongJae Park &lt;sj@kernel.org&gt;
Cc: Song Liu &lt;songliubraving@fb.com&gt;
Cc: Thomas Bogendoerfer &lt;tsbogend@alpha.franken.de&gt;
Cc: Vlastimil Babka &lt;vbabka@suse.cz&gt;
Cc: Yang Shi &lt;shy828301@gmail.com&gt;
Cc: Zi Yan &lt;ziy@nvidia.com&gt;
Cc: Dan Carpenter &lt;dan.carpenter@oracle.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'tty-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty</title>
<updated>2022-06-03T18:08:40+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2022-06-03T18:08:40+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=932c2989b59008e530ffcc7c7e6ef507a28b28ca'/>
<id>932c2989b59008e530ffcc7c7e6ef507a28b28ca</id>
<content type='text'>
Pull tty and serial driver updates from Greg KH:
 "Here is the big set of tty and serial driver updates for 5.19-rc1.

  Lots of tiny cleanups in here, the major stuff is:

   - termbit cleanups and unification by Ilpo. A much needed change that
     goes a long way to making things simpler for all of the different
     arches

   - tty documentation cleanups and movements to their own place in the
     documentation tree

   - old tty driver cleanups and fixes from Jiri to bring some existing
     drivers into the modern world

   - RS485 cleanups and unifications to make it easier for individual
     drivers to support this mode instead of having to duplicate logic
     in each driver

   - Lots of 8250 driver updates and additions

   - new device id additions

   - n_gsm continued fixes and cleanups

   - other minor serial driver updates and cleanups

  All of these have been in linux-next for weeks with no reported issues"

* tag 'tty-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (166 commits)
  tty: Rework receive flow control char logic
  pcmcia: synclink_cs: Don't allow CS5-6
  serial: stm32-usart: Correct CSIZE, bits, and parity
  serial: st-asc: Sanitize CSIZE and correct PARENB for CS7
  serial: sifive: Sanitize CSIZE and c_iflag
  serial: sh-sci: Don't allow CS5-6
  serial: txx9: Don't allow CS5-6
  serial: rda-uart: Don't allow CS5-6
  serial: digicolor-usart: Don't allow CS5-6
  serial: uartlite: Fix BRKINT clearing
  serial: cpm_uart: Fix build error without CONFIG_SERIAL_CPM_CONSOLE
  serial: core: Do stop_rx in suspend path for console if console_suspend is disabled
  tty: serial: qcom-geni-serial: Remove uart frequency table. Instead, find suitable frequency with call to clk_round_rate.
  dt-bindings: serial: renesas,em-uart: Add RZ/V2M clock to access the registers
  serial: 8250_fintek: Check SER_RS485_RTS_* only with RS485
  Revert "serial: 8250_mtk: Make sure to select the right FEATURE_SEL"
  serial: msm_serial: disable interrupts in __msm_console_write()
  serial: meson: acquire port-&gt;lock in startup()
  serial: 8250_dw: Use dev_err_probe()
  serial: 8250_dw: Use devm_add_action_or_reset()
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull tty and serial driver updates from Greg KH:
 "Here is the big set of tty and serial driver updates for 5.19-rc1.

  Lots of tiny cleanups in here, the major stuff is:

   - termbit cleanups and unification by Ilpo. A much needed change that
     goes a long way to making things simpler for all of the different
     arches

   - tty documentation cleanups and movements to their own place in the
     documentation tree

   - old tty driver cleanups and fixes from Jiri to bring some existing
     drivers into the modern world

   - RS485 cleanups and unifications to make it easier for individual
     drivers to support this mode instead of having to duplicate logic
     in each driver

   - Lots of 8250 driver updates and additions

   - new device id additions

   - n_gsm continued fixes and cleanups

   - other minor serial driver updates and cleanups

  All of these have been in linux-next for weeks with no reported issues"

* tag 'tty-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (166 commits)
  tty: Rework receive flow control char logic
  pcmcia: synclink_cs: Don't allow CS5-6
  serial: stm32-usart: Correct CSIZE, bits, and parity
  serial: st-asc: Sanitize CSIZE and correct PARENB for CS7
  serial: sifive: Sanitize CSIZE and c_iflag
  serial: sh-sci: Don't allow CS5-6
  serial: txx9: Don't allow CS5-6
  serial: rda-uart: Don't allow CS5-6
  serial: digicolor-usart: Don't allow CS5-6
  serial: uartlite: Fix BRKINT clearing
  serial: cpm_uart: Fix build error without CONFIG_SERIAL_CPM_CONSOLE
  serial: core: Do stop_rx in suspend path for console if console_suspend is disabled
  tty: serial: qcom-geni-serial: Remove uart frequency table. Instead, find suitable frequency with call to clk_round_rate.
  dt-bindings: serial: renesas,em-uart: Add RZ/V2M clock to access the registers
  serial: 8250_fintek: Check SER_RS485_RTS_* only with RS485
  Revert "serial: 8250_mtk: Make sure to select the right FEATURE_SEL"
  serial: msm_serial: disable interrupts in __msm_console_write()
  serial: meson: acquire port-&gt;lock in startup()
  serial: 8250_dw: Use dev_err_probe()
  serial: 8250_dw: Use devm_add_action_or_reset()
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>termbits.h: Remove posix_types.h include</title>
<updated>2022-05-19T16:25:26+00:00</updated>
<author>
<name>Ilpo Järvinen</name>
<email>ilpo.jarvinen@linux.intel.com</email>
</author>
<published>2022-05-09T09:34:46+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=44e0b165b6c078b84767da4ba06ffa27af562c96'/>
<id>44e0b165b6c078b84767da4ba06ffa27af562c96</id>
<content type='text'>
Nothing in termbits seems to require anything from linux/posix_types.h.

Signed-off-by: Ilpo Järvinen &lt;ilpo.jarvinen@linux.intel.com&gt;
Link: https://lore.kernel.org/r/20220509093446.6677-4-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Nothing in termbits seems to require anything from linux/posix_types.h.

Signed-off-by: Ilpo Järvinen &lt;ilpo.jarvinen@linux.intel.com&gt;
Link: https://lore.kernel.org/r/20220509093446.6677-4-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>termbits.h: Align lines &amp; format</title>
<updated>2022-05-19T16:25:26+00:00</updated>
<author>
<name>Ilpo Järvinen</name>
<email>ilpo.jarvinen@linux.intel.com</email>
</author>
<published>2022-05-09T09:34:45+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=c9b34088e80efe30459517fa3834cf78532c9a02'/>
<id>c9b34088e80efe30459517fa3834cf78532c9a02</id>
<content type='text'>
- Align c_cc defines.
- Remove extra newlines.
- Realign &amp; adjust number of leading zeros.
- Reorder c_cflag defines to ascending order
- Make comment ending shorted (=remove period and one extra space from
  the comments in mips).

Co-developed-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Signed-off-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Signed-off-by: Ilpo Järvinen &lt;ilpo.jarvinen@linux.intel.com&gt;
Link: https://lore.kernel.org/r/20220509093446.6677-3-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
- Align c_cc defines.
- Remove extra newlines.
- Realign &amp; adjust number of leading zeros.
- Reorder c_cflag defines to ascending order
- Make comment ending shorted (=remove period and one extra space from
  the comments in mips).

Co-developed-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Signed-off-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Signed-off-by: Ilpo Järvinen &lt;ilpo.jarvinen@linux.intel.com&gt;
Link: https://lore.kernel.org/r/20220509093446.6677-3-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>termbits.h: create termbits-common.h for identical bits</title>
<updated>2022-05-19T16:25:25+00:00</updated>
<author>
<name>Ilpo Järvinen</name>
<email>ilpo.jarvinen@linux.intel.com</email>
</author>
<published>2022-05-09T09:34:44+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=0b46ac44f2673be2ee51bb52149cab3546ff1696'/>
<id>0b46ac44f2673be2ee51bb52149cab3546ff1696</id>
<content type='text'>
Some defines are the same across all archs. Move the most obvious
intersection to termbits-common.h.

Signed-off-by: Ilpo Järvinen &lt;ilpo.jarvinen@linux.intel.com&gt;
Link: https://lore.kernel.org/r/20220509093446.6677-2-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Some defines are the same across all archs. Move the most obvious
intersection to termbits-common.h.

Signed-off-by: Ilpo Järvinen &lt;ilpo.jarvinen@linux.intel.com&gt;
Link: https://lore.kernel.org/r/20220509093446.6677-2-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>termbits: Convert octal defines to hex</title>
<updated>2022-05-05T20:43:58+00:00</updated>
<author>
<name>Ilpo Järvinen</name>
<email>ilpo.jarvinen@linux.intel.com</email>
</author>
<published>2022-05-04T07:20:46+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=6808b7f5c8255d07d79cb8eac40047f59e4154ad'/>
<id>6808b7f5c8255d07d79cb8eac40047f59e4154ad</id>
<content type='text'>
Many archs have termbits.h as octal numbers. It makes hard for humans
to parse the magnitude of large numbers correctly and to compare with
hex ones of the same define.

Convert octal values to hex.

First step is an automated conversion with:

for i in $(git ls-files | grep 'termbits\.h'); do
	awk --non-decimal-data '/^#define\s+[A-Z][A-Z0-9]*\s+0[0-9]/ {
		l=int(((length($3) - 1) * 3 + 3) / 4);
		repl = sprintf("0x%0" l "x", $3);
		print gensub(/[^[:blank:]]+/, repl, 3);
		next} {print}' $i &gt; $i~;
	mv $i~ $i;
done

On top of that, some manual processing on alignment and number of zeros.
In addition, small tweaks to formatting of a few comments on the same
lines.

Signed-off-by: Ilpo Järvinen &lt;ilpo.jarvinen@linux.intel.com&gt;
Acked-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Acked-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt; (powerpc)
Link: https://lore.kernel.org/r/2c8c96f-a12f-aadc-18ac-34c1d371929c@linux.intel.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Many archs have termbits.h as octal numbers. It makes hard for humans
to parse the magnitude of large numbers correctly and to compare with
hex ones of the same define.

Convert octal values to hex.

First step is an automated conversion with:

for i in $(git ls-files | grep 'termbits\.h'); do
	awk --non-decimal-data '/^#define\s+[A-Z][A-Z0-9]*\s+0[0-9]/ {
		l=int(((length($3) - 1) * 3 + 3) / 4);
		repl = sprintf("0x%0" l "x", $3);
		print gensub(/[^[:blank:]]+/, repl, 3);
		next} {print}' $i &gt; $i~;
	mv $i~ $i;
done

On top of that, some manual processing on alignment and number of zeros.
In addition, small tweaks to formatting of a few comments on the same
lines.

Signed-off-by: Ilpo Järvinen &lt;ilpo.jarvinen@linux.intel.com&gt;
Acked-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Acked-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt; (powerpc)
Link: https://lore.kernel.org/r/2c8c96f-a12f-aadc-18ac-34c1d371929c@linux.intel.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: SO_RCVMARK socket option for SO_MARK with recvmsg()</title>
<updated>2022-04-28T20:08:15+00:00</updated>
<author>
<name>Erin MacNeil</name>
<email>lnx.erin@gmail.com</email>
</author>
<published>2022-04-27T20:02:37+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=6fd1d51cfa253b5ee7dae18d7cf1df830e9b6137'/>
<id>6fd1d51cfa253b5ee7dae18d7cf1df830e9b6137</id>
<content type='text'>
Adding a new socket option, SO_RCVMARK, to indicate that SO_MARK
should be included in the ancillary data returned by recvmsg().

Renamed the sock_recv_ts_and_drops() function to sock_recv_cmsgs().

Signed-off-by: Erin MacNeil &lt;lnx.erin@gmail.com&gt;
Reviewed-by: Eric Dumazet &lt;edumazet@google.com&gt;
Reviewed-by: David Ahern &lt;dsahern@kernel.org&gt;
Acked-by: Marc Kleine-Budde &lt;mkl@pengutronix.de&gt;
Link: https://lore.kernel.org/r/20220427200259.2564-1-lnx.erin@gmail.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Adding a new socket option, SO_RCVMARK, to indicate that SO_MARK
should be included in the ancillary data returned by recvmsg().

Renamed the sock_recv_ts_and_drops() function to sock_recv_cmsgs().

Signed-off-by: Erin MacNeil &lt;lnx.erin@gmail.com&gt;
Reviewed-by: Eric Dumazet &lt;edumazet@google.com&gt;
Reviewed-by: David Ahern &lt;dsahern@kernel.org&gt;
Acked-by: Marc Kleine-Budde &lt;mkl@pengutronix.de&gt;
Link: https://lore.kernel.org/r/20220427200259.2564-1-lnx.erin@gmail.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>mm: madvise: MADV_DONTNEED_LOCKED</title>
<updated>2022-03-25T02:06:51+00:00</updated>
<author>
<name>Johannes Weiner</name>
<email>hannes@cmpxchg.org</email>
</author>
<published>2022-03-25T01:14:12+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=9457056ac426e5ed0671356509c8dcce69f8dee0'/>
<id>9457056ac426e5ed0671356509c8dcce69f8dee0</id>
<content type='text'>
MADV_DONTNEED historically rejects mlocked ranges, but with MLOCK_ONFAULT
and MCL_ONFAULT allowing to mlock without populating, there are valid use
cases for depopulating locked ranges as well.

Users mlock memory to protect secrets.  There are allocators for secure
buffers that want in-use memory generally mlocked, but cleared and
invalidated memory to give up the physical pages.  This could be done with
explicit munlock -&gt; mlock calls on free -&gt; alloc of course, but that adds
two unnecessary syscalls, heavy mmap_sem write locks, vma splits and
re-merges - only to get rid of the backing pages.

Users also mlockall(MCL_ONFAULT) to suppress sustained paging, but are
okay with on-demand initial population.  It seems valid to selectively
free some memory during the lifetime of such a process, without having to
mess with its overall policy.

Why add a separate flag? Isn't this a pretty niche usecase?

- MADV_DONTNEED has been bailing on locked vmas forever. It's at least
  conceivable that someone, somewhere is relying on mlock to protect
  data from perhaps broader invalidation calls. Changing this behavior
  now could lead to quiet data corruption.

- It also clarifies expectations around MADV_FREE and maybe
  MADV_REMOVE. It avoids the situation where one quietly behaves
  different than the others. MADV_FREE_LOCKED can be added later.

- The combination of mlock() and madvise() in the first place is
  probably niche. But where it happens, I'd say that dropping pages
  from a locked region once they don't contain secrets or won't page
  anymore is much saner than relying on mlock to protect memory from
  speculative or errant invalidation calls. It's just that we can't
  change the default behavior because of the two previous points.

Given that, an explicit new flag seems to make the most sense.

[hannes@cmpxchg.org: fix mips build]

Link: https://lkml.kernel.org/r/20220304171912.305060-1-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner &lt;hannes@cmpxchg.org&gt;
Acked-by: Michal Hocko &lt;mhocko@suse.com&gt;
Reviewed-by: Mike Kravetz &lt;mike.kravetz@oracle.com&gt;
Reviewed-by: Shakeel Butt &lt;shakeelb@google.com&gt;
Acked-by: Vlastimil Babka &lt;vbabka@suse.cz&gt;
Cc: Nadav Amit &lt;nadav.amit@gmail.com&gt;
Cc: David Hildenbrand &lt;david@redhat.com&gt;
Cc: Dr. David Alan Gilbert &lt;dgilbert@redhat.com&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>
MADV_DONTNEED historically rejects mlocked ranges, but with MLOCK_ONFAULT
and MCL_ONFAULT allowing to mlock without populating, there are valid use
cases for depopulating locked ranges as well.

Users mlock memory to protect secrets.  There are allocators for secure
buffers that want in-use memory generally mlocked, but cleared and
invalidated memory to give up the physical pages.  This could be done with
explicit munlock -&gt; mlock calls on free -&gt; alloc of course, but that adds
two unnecessary syscalls, heavy mmap_sem write locks, vma splits and
re-merges - only to get rid of the backing pages.

Users also mlockall(MCL_ONFAULT) to suppress sustained paging, but are
okay with on-demand initial population.  It seems valid to selectively
free some memory during the lifetime of such a process, without having to
mess with its overall policy.

Why add a separate flag? Isn't this a pretty niche usecase?

- MADV_DONTNEED has been bailing on locked vmas forever. It's at least
  conceivable that someone, somewhere is relying on mlock to protect
  data from perhaps broader invalidation calls. Changing this behavior
  now could lead to quiet data corruption.

- It also clarifies expectations around MADV_FREE and maybe
  MADV_REMOVE. It avoids the situation where one quietly behaves
  different than the others. MADV_FREE_LOCKED can be added later.

- The combination of mlock() and madvise() in the first place is
  probably niche. But where it happens, I'd say that dropping pages
  from a locked region once they don't contain secrets or won't page
  anymore is much saner than relying on mlock to protect memory from
  speculative or errant invalidation calls. It's just that we can't
  change the default behavior because of the two previous points.

Given that, an explicit new flag seems to make the most sense.

[hannes@cmpxchg.org: fix mips build]

Link: https://lkml.kernel.org/r/20220304171912.305060-1-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner &lt;hannes@cmpxchg.org&gt;
Acked-by: Michal Hocko &lt;mhocko@suse.com&gt;
Reviewed-by: Mike Kravetz &lt;mike.kravetz@oracle.com&gt;
Reviewed-by: Shakeel Butt &lt;shakeelb@google.com&gt;
Acked-by: Vlastimil Babka &lt;vbabka@suse.cz&gt;
Cc: Nadav Amit &lt;nadav.amit@gmail.com&gt;
Cc: David Hildenbrand &lt;david@redhat.com&gt;
Cc: Dr. David Alan Gilbert &lt;dgilbert@redhat.com&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>
