<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-dev/arch/powerpc/kernel/syscalls, branch master</title>
<subtitle>Linux kernel development work - see feature branches</subtitle>
<id>https://git.zx2c4.com/linux-dev/atom/arch/powerpc/kernel/syscalls?h=master</id>
<link rel='self' href='https://git.zx2c4.com/linux-dev/atom/arch/powerpc/kernel/syscalls?h=master'/>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/'/>
<updated>2022-10-31T23:24:09Z</updated>
<entry>
<title>powerpc/32: fix syscall wrappers with 64-bit arguments</title>
<updated>2022-10-31T23:24:09Z</updated>
<author>
<name>Andreas Schwab</name>
<email>schwab@linux-m68k.org</email>
</author>
<published>2022-10-31T14:47:35Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=ce883a2ba310cd7c291bb66ce5d207965fca6003'/>
<id>urn:sha1:ce883a2ba310cd7c291bb66ce5d207965fca6003</id>
<content type='text'>
With the introduction of syscall wrappers all wrappers for syscalls with
64-bit arguments must be handled specially, not only those that have
unaligned 64-bit arguments. This left out the fallocate() and
sync_file_range2() syscalls.

Fixes: 7e92e01b7245 ("powerpc: Provide syscall wrapper")
Fixes: e23750623835 ("powerpc/32: fix syscall wrappers with 64-bit arguments of unaligned register-pairs")
Signed-off-by: Andreas Schwab &lt;schwab@linux-m68k.org&gt;
Reviewed-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/87mt9cxd6g.fsf_-_@igel.home
</content>
</entry>
<entry>
<title>powerpc/32: fix syscall wrappers with 64-bit arguments of unaligned register-pairs</title>
<updated>2022-10-12T13:49:58Z</updated>
<author>
<name>Nicholas Piggin</name>
<email>npiggin@gmail.com</email>
</author>
<published>2022-10-12T03:53:34Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=e237506238352f3bfa9cf3983cdab873e35651eb'/>
<id>urn:sha1:e237506238352f3bfa9cf3983cdab873e35651eb</id>
<content type='text'>
powerpc 32-bit system call (and function) calling convention for 64-bit
arguments requires the next available odd-pair (two sequential registers
with the first being odd-numbered) from the standard register argument
allocation.

The first argument register is r3, so a 64-bit argument that appears at
an even position in the argument list must skip a register (unless there
were preceding 64-bit arguments, which might throw things off). This
requires non-standard compat definitions to deal with the holes in the
argument register allocation.

With pt_regs syscall wrappers which use a standard mapper to map pt_regs
GPRs to function arguments, 32-bit kernels hit the same basic problem,
the standard definitions don't cope with the unused argument registers.

Fix this by having 32-bit kernels share those syscall definitions with
compat.

Thanks to Jason for spending a lot of time finding and bisecting this
and developing a trivial reproducer. The perfect bug report.

Reported-by: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
Signed-off-by: Nicholas Piggin &lt;npiggin@gmail.com&gt;
Fixes: 7e92e01b72452 ("powerpc: Provide syscall wrapper")
Reviewed-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/20221012035335.866440-1-npiggin@gmail.com
</content>
</entry>
<entry>
<title>powerpc: Adopt SYSCALL_DEFINE for arch-specific syscall handlers</title>
<updated>2022-09-28T09:22:08Z</updated>
<author>
<name>Rohan McLure</name>
<email>rmclure@linux.ibm.com</email>
</author>
<published>2022-09-21T06:55:55Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=dec20c50df79cadaff17e964ef7f622491a52134'/>
<id>urn:sha1:dec20c50df79cadaff17e964ef7f622491a52134</id>
<content type='text'>
Arch-specific implementations of syscall handlers are currently used
over generic implementations for the following reasons:

1. Semantics unique to powerpc
2. Compatibility syscalls require 'argument padding' to comply with
   64-bit argument convention in ELF32 abi.
3. Parameter types or order is different in other architectures.

These syscall handlers have been defined prior to this patch series
without invoking the SYSCALL_DEFINE or COMPAT_SYSCALL_DEFINE macros with
custom input and output types. We remove every such direct definition in
favour of the aforementioned macros.

Also update syscalls.tbl in order to refer to the symbol names generated
by each of these macros. Since ppc64_personality can be called by both
64 bit and 32 bit binaries through compatibility, we must generate both
both compat_sys_ and sys_ symbols for this handler.

As an aside:
A number of architectures including arm and powerpc agree on an
alternative argument order and numbering for most of these arch-specific
handlers. A future patch series may allow for asm/unistd.h to signal
through its defines that a generic implementation of these syscall
handlers with the correct calling convention be emitted, through the
__ARCH_WANT_COMPAT_SYS_... convention.

Signed-off-by: Rohan McLure &lt;rmclure@linux.ibm.com&gt;
Reviewed-by: Nicholas Piggin &lt;npiggin@gmail.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/20220921065605.1051927-16-rmclure@linux.ibm.com

</content>
</entry>
<entry>
<title>powerpc/32: Remove powerpc select specialisation</title>
<updated>2022-09-26T13:00:15Z</updated>
<author>
<name>Rohan McLure</name>
<email>rmclure@linux.ibm.com</email>
</author>
<published>2022-09-21T06:55:51Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=b6b1334c9510e162bd8ca0ae58403cafad9572f1'/>
<id>urn:sha1:b6b1334c9510e162bd8ca0ae58403cafad9572f1</id>
<content type='text'>
Syscall #82 has been implemented for 32-bit platforms in a unique way on
powerpc systems. This hack will in effect guess whether the caller is
expecting new select semantics or old select semantics. It does so via a
guess, based off the first parameter. In new select, this parameter
represents the length of a user-memory array of file descriptors, and in
old select this is a pointer to an arguments structure.

The heuristic simply interprets sufficiently large values of its first
parameter as being a call to old select. The following is a discussion
on how this syscall should be handled.


As discussed in this thread, the existence of such a hack suggests that for
whatever powerpc binaries may predate glibc, it is most likely that they
would have taken use of the old select semantics. x86 and arm64 both
implement this syscall with oldselect semantics.

Remove the powerpc implementation, and update syscall.tbl to refer to emit
a reference to sys_old_select and compat_sys_old_select
for 32-bit binaries, in keeping with how other architectures support
syscall #82.

Signed-off-by: Rohan McLure &lt;rmclure@linux.ibm.com&gt;
Reviewed-by: Nicholas Piggin &lt;npiggin@gmail.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/lkml/13737de5-0eb7-e881-9af0-163b0d29a1a0@csgroup.eu/
Link: https://lore.kernel.org/r/20220921065605.1051927-12-rmclure@linux.ibm.com

</content>
</entry>
<entry>
<title>arch: syscalls: simplify uapi/kapi directory creation</title>
<updated>2022-03-31T03:03:46Z</updated>
<author>
<name>Masahiro Yamada</name>
<email>masahiroy@kernel.org</email>
</author>
<published>2022-02-27T09:10:24Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=bbc90bc1bd4a63121bae9cbfafe1e1f0beaf24b1'/>
<id>urn:sha1:bbc90bc1bd4a63121bae9cbfafe1e1f0beaf24b1</id>
<content type='text'>
$(shell ...) expands to empty. There is no need to assign it to _dummy.

Signed-off-by: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
Acked-by: Geert Uytterhoeven &lt;geert@linux-m68k.org&gt;
</content>
</entry>
<entry>
<title>mm/mempolicy: wire up syscall set_mempolicy_home_node</title>
<updated>2022-01-15T14:30:30Z</updated>
<author>
<name>Aneesh Kumar K.V</name>
<email>aneesh.kumar@linux.ibm.com</email>
</author>
<published>2022-01-14T22:08:21Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=21b084fdf2a49ca1634e8e360e9ab6f9ff0dee11'/>
<id>urn:sha1:21b084fdf2a49ca1634e8e360e9ab6f9ff0dee11</id>
<content type='text'>
Link: https://lkml.kernel.org/r/20211202123810.267175-4-aneesh.kumar@linux.ibm.com
Signed-off-by: Aneesh Kumar K.V &lt;aneesh.kumar@linux.ibm.com&gt;
Cc: Ben Widawsky &lt;ben.widawsky@intel.com&gt;
Cc: Dave Hansen &lt;dave.hansen@linux.intel.com&gt;
Cc: Feng Tang &lt;feng.tang@intel.com&gt;
Cc: Michal Hocko &lt;mhocko@kernel.org&gt;
Cc: Andrea Arcangeli &lt;aarcange@redhat.com&gt;
Cc: Mel Gorman &lt;mgorman@techsingularity.net&gt;
Cc: Mike Kravetz &lt;mike.kravetz@oracle.com&gt;
Cc: Randy Dunlap &lt;rdunlap@infradead.org&gt;
Cc: Vlastimil Babka &lt;vbabka@suse.cz&gt;
Cc: Andi Kleen &lt;ak@linux.intel.com&gt;
Cc: Dan Williams &lt;dan.j.williams@intel.com&gt;
Cc: Huang Ying &lt;ying.huang@intel.com&gt;
Cc: &lt;linux-api@vger.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>
</entry>
<entry>
<title>futex: Wireup futex_waitv syscall</title>
<updated>2021-11-25T13:26:12Z</updated>
<author>
<name>André Almeida</name>
<email>andrealmeid@collabora.com</email>
</author>
<published>2021-11-24T13:21:12Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=a0eb2da92b715d0c97b96b09979689ea09faefe6'/>
<id>urn:sha1:a0eb2da92b715d0c97b96b09979689ea09faefe6</id>
<content type='text'>
Wireup futex_waitv syscall for all remaining archs.

Signed-off-by: André Almeida &lt;andrealmeid@collabora.com&gt;
Acked-by: Max Filippov &lt;jcmvbkbc@gmail.com&gt;
Acked-by: Geert Uytterhoeven &lt;geert@linux-m68k.org&gt;
Tested-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt; (powerpc)
Signed-off-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
</content>
</entry>
<entry>
<title>compat: remove some compat entry points</title>
<updated>2021-09-08T22:32:35Z</updated>
<author>
<name>Arnd Bergmann</name>
<email>arnd@arndb.de</email>
</author>
<published>2021-09-08T22:18:25Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=59ab844eed9c6b01d32dcb27b57accc23771b324'/>
<id>urn:sha1:59ab844eed9c6b01d32dcb27b57accc23771b324</id>
<content type='text'>
These are all handled correctly when calling the native system call entry
point, so remove the special cases.

Link: https://lkml.kernel.org/r/20210727144859.4150043-6-arnd@kernel.org
Signed-off-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Reviewed-by: Christoph Hellwig &lt;hch@lst.de&gt;
Cc: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
Cc: Benjamin Herrenschmidt &lt;benh@kernel.crashing.org&gt;
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Christian Borntraeger &lt;borntraeger@de.ibm.com&gt;
Cc: Christoph Hellwig &lt;hch@infradead.org&gt;
Cc: "David S. Miller" &lt;davem@davemloft.net&gt;
Cc: Eric Biederman &lt;ebiederm@xmission.com&gt;
Cc: Feng Tang &lt;feng.tang@intel.com&gt;
Cc: Heiko Carstens &lt;hca@linux.ibm.com&gt;
Cc: Helge Deller &lt;deller@gmx.de&gt;
Cc: "H. Peter Anvin" &lt;hpa@zytor.com&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: "James E.J. Bottomley" &lt;James.Bottomley@HansenPartnership.com&gt;
Cc: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Cc: Paul Mackerras &lt;paulus@samba.org&gt;
Cc: Thomas Bogendoerfer &lt;tsbogend@alpha.franken.de&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Vasily Gorbik &lt;gor@linux.ibm.com&gt;
Cc: Will Deacon &lt;will@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>
</entry>
<entry>
<title>Merge branch 'akpm' (patches from Andrew)</title>
<updated>2021-09-03T17:08:28Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2021-09-03T17:08:28Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=14726903c835101cd8d0a703b609305094350d61'/>
<id>urn:sha1:14726903c835101cd8d0a703b609305094350d61</id>
<content type='text'>
Merge misc updates from Andrew Morton:
 "173 patches.

  Subsystems affected by this series: ia64, ocfs2, block, and mm (debug,
  pagecache, gup, swap, shmem, memcg, selftests, pagemap, mremap,
  bootmem, sparsemem, vmalloc, kasan, pagealloc, memory-failure,
  hugetlb, userfaultfd, vmscan, compaction, mempolicy, memblock,
  oom-kill, migration, ksm, percpu, vmstat, and madvise)"

* emailed patches from Andrew Morton &lt;akpm@linux-foundation.org&gt;: (173 commits)
  mm/madvise: add MADV_WILLNEED to process_madvise()
  mm/vmstat: remove unneeded return value
  mm/vmstat: simplify the array size calculation
  mm/vmstat: correct some wrong comments
  mm/percpu,c: remove obsolete comments of pcpu_chunk_populated()
  selftests: vm: add COW time test for KSM pages
  selftests: vm: add KSM merging time test
  mm: KSM: fix data type
  selftests: vm: add KSM merging across nodes test
  selftests: vm: add KSM zero page merging test
  selftests: vm: add KSM unmerge test
  selftests: vm: add KSM merge test
  mm/migrate: correct kernel-doc notation
  mm: wire up syscall process_mrelease
  mm: introduce process_mrelease system call
  memblock: make memblock_find_in_range method private
  mm/mempolicy.c: use in_task() in mempolicy_slab_node()
  mm/mempolicy: unify the create() func for bind/interleave/prefer-many policies
  mm/mempolicy: advertise new MPOL_PREFERRED_MANY
  mm/hugetlb: add support for mempolicy MPOL_PREFERRED_MANY
  ...
</content>
</entry>
<entry>
<title>mm: wire up syscall process_mrelease</title>
<updated>2021-09-03T16:58:17Z</updated>
<author>
<name>Suren Baghdasaryan</name>
<email>surenb@google.com</email>
</author>
<published>2021-09-02T22:00:33Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=dce49103962840dd61423d7627748d6c558d58c5'/>
<id>urn:sha1:dce49103962840dd61423d7627748d6c558d58c5</id>
<content type='text'>
Split off from prev patch in the series that implements the syscall.

Link: https://lkml.kernel.org/r/20210809185259.405936-2-surenb@google.com
Signed-off-by: Suren Baghdasaryan &lt;surenb@google.com&gt;
Acked-by: Geert Uytterhoeven &lt;geert@linux-m68k.org&gt;
Cc: Andy Lutomirski &lt;luto@kernel.org&gt;
Cc: Christian Brauner &lt;christian.brauner@ubuntu.com&gt;
Cc: Christoph Hellwig &lt;hch@infradead.org&gt;
Cc: David Hildenbrand &lt;david@redhat.com&gt;
Cc: David Rientjes &lt;rientjes@google.com&gt;
Cc: Florian Weimer &lt;fweimer@redhat.com&gt;
Cc: Jan Engelhardt &lt;jengelh@inai.de&gt;
Cc: Jann Horn &lt;jannh@google.com&gt;
Cc: Johannes Weiner &lt;hannes@cmpxchg.org&gt;
Cc: Matthew Wilcox (Oracle) &lt;willy@infradead.org&gt;
Cc: Michal Hocko &lt;mhocko@suse.com&gt;
Cc: Minchan Kim &lt;minchan@kernel.org&gt;
Cc: Oleg Nesterov &lt;oleg@redhat.com&gt;
Cc: Rik van Riel &lt;riel@surriel.com&gt;
Cc: Roman Gushchin &lt;guro@fb.com&gt;
Cc: Shakeel Butt &lt;shakeelb@google.com&gt;
Cc: Tim Murray &lt;timmurray@google.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>
</entry>
</feed>
