<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/arch/powerpc/include, branch v5.4.296</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>powerpc: Fix struct termio related ioctl macros</title>
<updated>2025-07-17T16:24:57+00:00</updated>
<author>
<name>Madhavan Srinivasan</name>
<email>maddy@linux.ibm.com</email>
</author>
<published>2025-05-17T14:22:37+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=f2aec1069f5d792511b47d5c1124da7907eb53ef'/>
<id>f2aec1069f5d792511b47d5c1124da7907eb53ef</id>
<content type='text'>
[ Upstream commit ab107276607af90b13a5994997e19b7b9731e251 ]

Since termio interface is now obsolete, include/uapi/asm/ioctls.h
has some constant macros referring to "struct termio", this caused
build failure at userspace.

In file included from /usr/include/asm/ioctl.h:12,
                 from /usr/include/asm/ioctls.h:5,
                 from tst-ioctls.c:3:
tst-ioctls.c: In function 'get_TCGETA':
tst-ioctls.c:12:10: error: invalid application of 'sizeof' to incomplete type 'struct termio'
   12 |   return TCGETA;
      |          ^~~~~~

Even though termios.h provides "struct termio", trying to juggle definitions around to
make it compile could introduce regressions. So better to open code it.

Reported-by: Tulio Magno &lt;tuliom@ascii.art.br&gt;
Suggested-by: Nicholas Piggin &lt;npiggin@gmail.com&gt;
Tested-by: Justin M. Forbes &lt;jforbes@fedoraproject.org&gt;
Reviewed-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Closes: https://lore.kernel.org/linuxppc-dev/8734dji5wl.fsf@ascii.art.br/
Signed-off-by: Madhavan Srinivasan &lt;maddy@linux.ibm.com&gt;
Link: https://patch.msgid.link/20250517142237.156665-1-maddy@linux.ibm.com
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 ab107276607af90b13a5994997e19b7b9731e251 ]

Since termio interface is now obsolete, include/uapi/asm/ioctls.h
has some constant macros referring to "struct termio", this caused
build failure at userspace.

In file included from /usr/include/asm/ioctl.h:12,
                 from /usr/include/asm/ioctls.h:5,
                 from tst-ioctls.c:3:
tst-ioctls.c: In function 'get_TCGETA':
tst-ioctls.c:12:10: error: invalid application of 'sizeof' to incomplete type 'struct termio'
   12 |   return TCGETA;
      |          ^~~~~~

Even though termios.h provides "struct termio", trying to juggle definitions around to
make it compile could introduce regressions. So better to open code it.

Reported-by: Tulio Magno &lt;tuliom@ascii.art.br&gt;
Suggested-by: Nicholas Piggin &lt;npiggin@gmail.com&gt;
Tested-by: Justin M. Forbes &lt;jforbes@fedoraproject.org&gt;
Reviewed-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Closes: https://lore.kernel.org/linuxppc-dev/8734dji5wl.fsf@ascii.art.br/
Signed-off-by: Madhavan Srinivasan &lt;maddy@linux.ibm.com&gt;
Link: https://patch.msgid.link/20250517142237.156665-1-maddy@linux.ibm.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc/64s: Rewrite __real_pte() and __rpte_to_hidx() as static inline</title>
<updated>2025-03-13T11:43:22+00:00</updated>
<author>
<name>Christophe Leroy</name>
<email>christophe.leroy@csgroup.eu</email>
</author>
<published>2025-01-12T18:24:46+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=2ecb66322458be3e2e23d4e6d95666f4fc21238d'/>
<id>2ecb66322458be3e2e23d4e6d95666f4fc21238d</id>
<content type='text'>
[ Upstream commit 61bcc752d1b81fde3cae454ff20c1d3c359df500 ]

Rewrite __real_pte() and __rpte_to_hidx() as static inline in order to
avoid following warnings/errors when building with 4k page size:

	  CC      arch/powerpc/mm/book3s64/hash_tlb.o
	arch/powerpc/mm/book3s64/hash_tlb.c: In function 'hpte_need_flush':
	arch/powerpc/mm/book3s64/hash_tlb.c:49:16: error: variable 'offset' set but not used [-Werror=unused-but-set-variable]
	   49 |         int i, offset;
	      |                ^~~~~~

	  CC      arch/powerpc/mm/book3s64/hash_native.o
	arch/powerpc/mm/book3s64/hash_native.c: In function 'native_flush_hash_range':
	arch/powerpc/mm/book3s64/hash_native.c:782:29: error: variable 'index' set but not used [-Werror=unused-but-set-variable]
	  782 |         unsigned long hash, index, hidx, shift, slot;
	      |                             ^~~~~

Reported-by: kernel test robot &lt;lkp@intel.com&gt;
Closes: https://lore.kernel.org/oe-kbuild-all/202501081741.AYFwybsq-lkp@intel.com/
Fixes: ff31e105464d ("powerpc/mm/hash64: Store the slot information at the right offset for hugetlb")
Signed-off-by: Christophe Leroy &lt;christophe.leroy@csgroup.eu&gt;
Reviewed-by: Ritesh Harjani (IBM) &lt;ritesh.list@gmail.com&gt;
Signed-off-by: Madhavan Srinivasan &lt;maddy@linux.ibm.com&gt;
Link: https://patch.msgid.link/e0d340a5b7bd478ecbf245d826e6ab2778b74e06.1736706263.git.christophe.leroy@csgroup.eu
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 61bcc752d1b81fde3cae454ff20c1d3c359df500 ]

Rewrite __real_pte() and __rpte_to_hidx() as static inline in order to
avoid following warnings/errors when building with 4k page size:

	  CC      arch/powerpc/mm/book3s64/hash_tlb.o
	arch/powerpc/mm/book3s64/hash_tlb.c: In function 'hpte_need_flush':
	arch/powerpc/mm/book3s64/hash_tlb.c:49:16: error: variable 'offset' set but not used [-Werror=unused-but-set-variable]
	   49 |         int i, offset;
	      |                ^~~~~~

	  CC      arch/powerpc/mm/book3s64/hash_native.o
	arch/powerpc/mm/book3s64/hash_native.c: In function 'native_flush_hash_range':
	arch/powerpc/mm/book3s64/hash_native.c:782:29: error: variable 'index' set but not used [-Werror=unused-but-set-variable]
	  782 |         unsigned long hash, index, hidx, shift, slot;
	      |                             ^~~~~

Reported-by: kernel test robot &lt;lkp@intel.com&gt;
Closes: https://lore.kernel.org/oe-kbuild-all/202501081741.AYFwybsq-lkp@intel.com/
Fixes: ff31e105464d ("powerpc/mm/hash64: Store the slot information at the right offset for hugetlb")
Signed-off-by: Christophe Leroy &lt;christophe.leroy@csgroup.eu&gt;
Reviewed-by: Ritesh Harjani (IBM) &lt;ritesh.list@gmail.com&gt;
Signed-off-by: Madhavan Srinivasan &lt;maddy@linux.ibm.com&gt;
Link: https://patch.msgid.link/e0d340a5b7bd478ecbf245d826e6ab2778b74e06.1736706263.git.christophe.leroy@csgroup.eu
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc/64s/mm: Move __real_pte stubs into hash-4k.h</title>
<updated>2025-03-13T11:43:22+00:00</updated>
<author>
<name>Michael Ellerman</name>
<email>mpe@ellerman.id.au</email>
</author>
<published>2024-08-21T08:07:29+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=fc4f8ac3b9c7daf691192c9556f103ce2db3c740'/>
<id>fc4f8ac3b9c7daf691192c9556f103ce2db3c740</id>
<content type='text'>
[ Upstream commit 8ae4f16f7d7b59cca55aeca6db7c9636ffe7fbaa ]

The stub versions of __real_pte() etc are only used with HPT &amp; 4K pages,
so move them into the hash-4k.h header.

Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://msgid.link/20240821080729.872034-1-mpe@ellerman.id.au
Stable-dep-of: 61bcc752d1b8 ("powerpc/64s: Rewrite __real_pte() and __rpte_to_hidx() as static inline")
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 8ae4f16f7d7b59cca55aeca6db7c9636ffe7fbaa ]

The stub versions of __real_pte() etc are only used with HPT &amp; 4K pages,
so move them into the hash-4k.h header.

Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://msgid.link/20240821080729.872034-1-mpe@ellerman.id.au
Stable-dep-of: 61bcc752d1b8 ("powerpc/64s: Rewrite __real_pte() and __rpte_to_hidx() as static inline")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc/sstep: make emulate_vsx_load and emulate_vsx_store static</title>
<updated>2024-12-14T18:44:30+00:00</updated>
<author>
<name>Michal Suchanek</name>
<email>msuchanek@suse.de</email>
</author>
<published>2024-10-01T13:03:49+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=1403e7b10c21586bd162586d1e3a7c2b782f3ad4'/>
<id>1403e7b10c21586bd162586d1e3a7c2b782f3ad4</id>
<content type='text'>
[ Upstream commit a26c4dbb3d9c1821cb0fc11cb2dbc32d5bf3463b ]

These functions are not used outside of sstep.c

Fixes: 350779a29f11 ("powerpc: Handle most loads and stores in instruction emulation code")
Signed-off-by: Michal Suchanek &lt;msuchanek@suse.de&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://patch.msgid.link/20241001130356.14664-1-msuchanek@suse.de
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 a26c4dbb3d9c1821cb0fc11cb2dbc32d5bf3463b ]

These functions are not used outside of sstep.c

Fixes: 350779a29f11 ("powerpc: Handle most loads and stores in instruction emulation code")
Signed-off-by: Michal Suchanek &lt;msuchanek@suse.de&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://patch.msgid.link/20241001130356.14664-1-msuchanek@suse.de
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc/vdso: Flag VDSO64 entry points as functions</title>
<updated>2024-12-14T18:44:28+00:00</updated>
<author>
<name>Christophe Leroy</name>
<email>christophe.leroy@csgroup.eu</email>
</author>
<published>2024-10-09T22:17:57+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=7022d187cb037fb610a5cf5c67e1f9f726d048d1'/>
<id>7022d187cb037fb610a5cf5c67e1f9f726d048d1</id>
<content type='text'>
[ Upstream commit 0161bd38c24312853ed5ae9a425a1c41c4ac674a ]

On powerpc64 as shown below by readelf, vDSO functions symbols have
type NOTYPE.

$ powerpc64-linux-gnu-readelf -a arch/powerpc/kernel/vdso/vdso64.so.dbg
ELF Header:
  Magic:   7f 45 4c 46 02 02 01 00 00 00 00 00 00 00 00 00
  Class:                             ELF64
  Data:                              2's complement, big endian
  Version:                           1 (current)
  OS/ABI:                            UNIX - System V
  ABI Version:                       0
  Type:                              DYN (Shared object file)
  Machine:                           PowerPC64
  Version:                           0x1
...

Symbol table '.dynsym' contains 12 entries:
   Num:    Value          Size Type    Bind   Vis      Ndx Name
...
     1: 0000000000000524    84 NOTYPE  GLOBAL DEFAULT    8 __[...]@@LINUX_2.6.15
...
     4: 0000000000000000     0 OBJECT  GLOBAL DEFAULT  ABS LINUX_2.6.15
     5: 00000000000006c0    48 NOTYPE  GLOBAL DEFAULT    8 __[...]@@LINUX_2.6.15

Symbol table '.symtab' contains 56 entries:
   Num:    Value          Size Type    Bind   Vis      Ndx Name
...
    45: 0000000000000000     0 OBJECT  GLOBAL DEFAULT  ABS LINUX_2.6.15
    46: 00000000000006c0    48 NOTYPE  GLOBAL DEFAULT    8 __kernel_getcpu
    47: 0000000000000524    84 NOTYPE  GLOBAL DEFAULT    8 __kernel_clock_getres

To overcome that, commit ba83b3239e65 ("selftests: vDSO: fix vDSO
symbols lookup for powerpc64") was applied to have selftests also
look for NOTYPE symbols, but the correct fix should be to flag VDSO
entry points as functions.

The original commit that brought VDSO support into powerpc/64 has the
following explanation:

    Note that the symbols exposed by the vDSO aren't "normal" function symbols, apps
    can't be expected to link against them directly, the vDSO's are both seen
    as if they were linked at 0 and the symbols just contain offsets to the
    various functions.  This is done on purpose to avoid a relocation step
    (ppc64 functions normally have descriptors with abs addresses in them).
    When glibc uses those functions, it's expected to use it's own trampolines
    that know how to reach them.

The descriptors it's talking about are the OPD function descriptors
used on ABI v1 (big endian). But it would be more correct for a text
symbol to have type function, even if there's no function descriptor
for it.

glibc has a special case already for handling the VDSO symbols which
creates a fake opd pointing at the kernel symbol. So changing the VDSO
symbol type to function shouldn't affect that.

For ABI v2, there is no function descriptors and VDSO functions can
safely have function type.

So lets flag VDSO entry points as functions and revert the
selftest change.

Link: https://github.com/mpe/linux-fullhistory/commit/5f2dd691b62da9d9cc54b938f8b29c22c93cb805
Fixes: ba83b3239e65 ("selftests: vDSO: fix vDSO symbols lookup for powerpc64")
Signed-off-by: Christophe Leroy &lt;christophe.leroy@csgroup.eu&gt;
Reviewed-By: Segher Boessenkool &lt;segher@kernel.crashing.org&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://patch.msgid.link/b6ad2f1ee9887af3ca5ecade2a56f4acda517a85.1728512263.git.christophe.leroy@csgroup.eu
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 0161bd38c24312853ed5ae9a425a1c41c4ac674a ]

On powerpc64 as shown below by readelf, vDSO functions symbols have
type NOTYPE.

$ powerpc64-linux-gnu-readelf -a arch/powerpc/kernel/vdso/vdso64.so.dbg
ELF Header:
  Magic:   7f 45 4c 46 02 02 01 00 00 00 00 00 00 00 00 00
  Class:                             ELF64
  Data:                              2's complement, big endian
  Version:                           1 (current)
  OS/ABI:                            UNIX - System V
  ABI Version:                       0
  Type:                              DYN (Shared object file)
  Machine:                           PowerPC64
  Version:                           0x1
...

Symbol table '.dynsym' contains 12 entries:
   Num:    Value          Size Type    Bind   Vis      Ndx Name
...
     1: 0000000000000524    84 NOTYPE  GLOBAL DEFAULT    8 __[...]@@LINUX_2.6.15
...
     4: 0000000000000000     0 OBJECT  GLOBAL DEFAULT  ABS LINUX_2.6.15
     5: 00000000000006c0    48 NOTYPE  GLOBAL DEFAULT    8 __[...]@@LINUX_2.6.15

Symbol table '.symtab' contains 56 entries:
   Num:    Value          Size Type    Bind   Vis      Ndx Name
...
    45: 0000000000000000     0 OBJECT  GLOBAL DEFAULT  ABS LINUX_2.6.15
    46: 00000000000006c0    48 NOTYPE  GLOBAL DEFAULT    8 __kernel_getcpu
    47: 0000000000000524    84 NOTYPE  GLOBAL DEFAULT    8 __kernel_clock_getres

To overcome that, commit ba83b3239e65 ("selftests: vDSO: fix vDSO
symbols lookup for powerpc64") was applied to have selftests also
look for NOTYPE symbols, but the correct fix should be to flag VDSO
entry points as functions.

The original commit that brought VDSO support into powerpc/64 has the
following explanation:

    Note that the symbols exposed by the vDSO aren't "normal" function symbols, apps
    can't be expected to link against them directly, the vDSO's are both seen
    as if they were linked at 0 and the symbols just contain offsets to the
    various functions.  This is done on purpose to avoid a relocation step
    (ppc64 functions normally have descriptors with abs addresses in them).
    When glibc uses those functions, it's expected to use it's own trampolines
    that know how to reach them.

The descriptors it's talking about are the OPD function descriptors
used on ABI v1 (big endian). But it would be more correct for a text
symbol to have type function, even if there's no function descriptor
for it.

glibc has a special case already for handling the VDSO symbols which
creates a fake opd pointing at the kernel symbol. So changing the VDSO
symbol type to function shouldn't affect that.

For ABI v2, there is no function descriptors and VDSO functions can
safely have function type.

So lets flag VDSO entry points as functions and revert the
selftest change.

Link: https://github.com/mpe/linux-fullhistory/commit/5f2dd691b62da9d9cc54b938f8b29c22c93cb805
Fixes: ba83b3239e65 ("selftests: vDSO: fix vDSO symbols lookup for powerpc64")
Signed-off-by: Christophe Leroy &lt;christophe.leroy@csgroup.eu&gt;
Reviewed-By: Segher Boessenkool &lt;segher@kernel.crashing.org&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://patch.msgid.link/b6ad2f1ee9887af3ca5ecade2a56f4acda517a85.1728512263.git.christophe.leroy@csgroup.eu
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc/64: Set _IO_BASE to POISON_POINTER_DELTA not 0 for CONFIG_PCI=n</title>
<updated>2024-07-18T09:40:49+00:00</updated>
<author>
<name>Michael Ellerman</name>
<email>mpe@ellerman.id.au</email>
</author>
<published>2024-05-03T07:56:19+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=048703bb5c1b444605c193681a843b83875e218e'/>
<id>048703bb5c1b444605c193681a843b83875e218e</id>
<content type='text'>
[ Upstream commit be140f1732b523947425aaafbe2e37b41b622d96 ]

There is code that builds with calls to IO accessors even when
CONFIG_PCI=n, but the actual calls are guarded by runtime checks.

If not those calls would be faulting, because the page at virtual
address zero is (usually) not mapped into the kernel. As Arnd pointed
out, it is possible a large port value could cause the address to be
above mmap_min_addr which would then access userspace, which would be
a bug.

To avoid any such issues, set _IO_BASE to POISON_POINTER_DELTA. That
is a value chosen to point into unmapped space between the kernel and
userspace, so any access will always fault.

Note that on 32-bit POISON_POINTER_DELTA is 0, so the patch only has an
effect on 64-bit.

Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://msgid.link/20240503075619.394467-2-mpe@ellerman.id.au
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 be140f1732b523947425aaafbe2e37b41b622d96 ]

There is code that builds with calls to IO accessors even when
CONFIG_PCI=n, but the actual calls are guarded by runtime checks.

If not those calls would be faulting, because the page at virtual
address zero is (usually) not mapped into the kernel. As Arnd pointed
out, it is possible a large port value could cause the address to be
above mmap_min_addr which would then access userspace, which would be
a bug.

To avoid any such issues, set _IO_BASE to POISON_POINTER_DELTA. That
is a value chosen to point into unmapped space between the kernel and
userspace, so any access will always fault.

Note that on 32-bit POISON_POINTER_DELTA is 0, so the patch only has an
effect on 64-bit.

Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://msgid.link/20240503075619.394467-2-mpe@ellerman.id.au
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc/io: Avoid clang null pointer arithmetic warnings</title>
<updated>2024-07-05T07:08:21+00:00</updated>
<author>
<name>Michael Ellerman</name>
<email>mpe@ellerman.id.au</email>
</author>
<published>2024-05-03T07:56:18+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=be601edecff8f0906e340e73fd85b319f76d39cc'/>
<id>be601edecff8f0906e340e73fd85b319f76d39cc</id>
<content type='text'>
[ Upstream commit 03c0f2c2b2220fc9cf8785cd7b61d3e71e24a366 ]

With -Wextra clang warns about pointer arithmetic using a null pointer.
When building with CONFIG_PCI=n, that triggers a warning in the IO
accessors, eg:

  In file included from linux/arch/powerpc/include/asm/io.h:672:
  linux/arch/powerpc/include/asm/io-defs.h:23:1: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
     23 | DEF_PCI_AC_RET(inb, u8, (unsigned long port), (port), pio, port)
        | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  ...
  linux/arch/powerpc/include/asm/io.h:591:53: note: expanded from macro '__do_inb'
    591 | #define __do_inb(port)          readb((PCI_IO_ADDR)_IO_BASE + port);
        |                                       ~~~~~~~~~~~~~~~~~~~~~ ^

That is because when CONFIG_PCI=n, _IO_BASE is defined as 0.

Although _IO_BASE is defined as plain 0, the cast (PCI_IO_ADDR) converts
it to void * before the addition with port happens.

Instead the addition can be done first, and then the cast. The resulting
value will be the same, but avoids the warning, and also avoids void
pointer arithmetic which is apparently non-standard.

Reported-by: Naresh Kamboju &lt;naresh.kamboju@linaro.org&gt;
Closes: https://lore.kernel.org/all/CA+G9fYtEh8zmq8k8wE-8RZwW-Qr927RLTn+KqGnq1F=ptaaNsA@mail.gmail.com
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://msgid.link/20240503075619.394467-1-mpe@ellerman.id.au
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
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<pre>
[ Upstream commit 03c0f2c2b2220fc9cf8785cd7b61d3e71e24a366 ]

With -Wextra clang warns about pointer arithmetic using a null pointer.
When building with CONFIG_PCI=n, that triggers a warning in the IO
accessors, eg:

  In file included from linux/arch/powerpc/include/asm/io.h:672:
  linux/arch/powerpc/include/asm/io-defs.h:23:1: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
     23 | DEF_PCI_AC_RET(inb, u8, (unsigned long port), (port), pio, port)
        | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  ...
  linux/arch/powerpc/include/asm/io.h:591:53: note: expanded from macro '__do_inb'
    591 | #define __do_inb(port)          readb((PCI_IO_ADDR)_IO_BASE + port);
        |                                       ~~~~~~~~~~~~~~~~~~~~~ ^

That is because when CONFIG_PCI=n, _IO_BASE is defined as 0.

Although _IO_BASE is defined as plain 0, the cast (PCI_IO_ADDR) converts
it to void * before the addition with port happens.

Instead the addition can be done first, and then the cast. The resulting
value will be the same, but avoids the warning, and also avoids void
pointer arithmetic which is apparently non-standard.

Reported-by: Naresh Kamboju &lt;naresh.kamboju@linaro.org&gt;
Closes: https://lore.kernel.org/all/CA+G9fYtEh8zmq8k8wE-8RZwW-Qr927RLTn+KqGnq1F=ptaaNsA@mail.gmail.com
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://msgid.link/20240503075619.394467-1-mpe@ellerman.id.au
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc/pseries: Enforce hcall result buffer validity and size</title>
<updated>2024-07-05T07:08:21+00:00</updated>
<author>
<name>Nathan Lynch</name>
<email>nathanl@linux.ibm.com</email>
</author>
<published>2024-04-08T14:08:31+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=19c166ee42cf16d8b156a6cb4544122d9a65d3ca'/>
<id>19c166ee42cf16d8b156a6cb4544122d9a65d3ca</id>
<content type='text'>
[ Upstream commit ff2e185cf73df480ec69675936c4ee75a445c3e4 ]

plpar_hcall(), plpar_hcall9(), and related functions expect callers to
provide valid result buffers of certain minimum size. Currently this
is communicated only through comments in the code and the compiler has
no idea.

For example, if I write a bug like this:

  long retbuf[PLPAR_HCALL_BUFSIZE]; // should be PLPAR_HCALL9_BUFSIZE
  plpar_hcall9(H_ALLOCATE_VAS_WINDOW, retbuf, ...);

This compiles with no diagnostics emitted, but likely results in stack
corruption at runtime when plpar_hcall9() stores results past the end
of the array. (To be clear this is a contrived example and I have not
found a real instance yet.)

To make this class of error less likely, we can use explicitly-sized
array parameters instead of pointers in the declarations for the hcall
APIs. When compiled with -Warray-bounds[1], the code above now
provokes a diagnostic like this:

error: array argument is too small;
is of size 32, callee requires at least 72 [-Werror,-Warray-bounds]
   60 |                 plpar_hcall9(H_ALLOCATE_VAS_WINDOW, retbuf,
      |                 ^                                   ~~~~~~

[1] Enabled for LLVM builds but not GCC for now. See commit
    0da6e5fd6c37 ("gcc: disable '-Warray-bounds' for gcc-13 too") and
    related changes.

Signed-off-by: Nathan Lynch &lt;nathanl@linux.ibm.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://msgid.link/20240408-pseries-hvcall-retbuf-v1-1-ebc73d7253cf@linux.ibm.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
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<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit ff2e185cf73df480ec69675936c4ee75a445c3e4 ]

plpar_hcall(), plpar_hcall9(), and related functions expect callers to
provide valid result buffers of certain minimum size. Currently this
is communicated only through comments in the code and the compiler has
no idea.

For example, if I write a bug like this:

  long retbuf[PLPAR_HCALL_BUFSIZE]; // should be PLPAR_HCALL9_BUFSIZE
  plpar_hcall9(H_ALLOCATE_VAS_WINDOW, retbuf, ...);

This compiles with no diagnostics emitted, but likely results in stack
corruption at runtime when plpar_hcall9() stores results past the end
of the array. (To be clear this is a contrived example and I have not
found a real instance yet.)

To make this class of error less likely, we can use explicitly-sized
array parameters instead of pointers in the declarations for the hcall
APIs. When compiled with -Warray-bounds[1], the code above now
provokes a diagnostic like this:

error: array argument is too small;
is of size 32, callee requires at least 72 [-Werror,-Warray-bounds]
   60 |                 plpar_hcall9(H_ALLOCATE_VAS_WINDOW, retbuf,
      |                 ^                                   ~~~~~~

[1] Enabled for LLVM builds but not GCC for now. See commit
    0da6e5fd6c37 ("gcc: disable '-Warray-bounds' for gcc-13 too") and
    related changes.

Signed-off-by: Nathan Lynch &lt;nathanl@linux.ibm.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://msgid.link/20240408-pseries-hvcall-retbuf-v1-1-ebc73d7253cf@linux.ibm.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc/pseries: Add failure related checks for h_get_mpp and h_get_ppp</title>
<updated>2024-06-16T11:28:44+00:00</updated>
<author>
<name>Shrikanth Hegde</name>
<email>sshegde@linux.ibm.com</email>
</author>
<published>2024-04-12T09:20:47+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=5b1796345d459077fec61e09ccd7175e9742c1f6'/>
<id>5b1796345d459077fec61e09ccd7175e9742c1f6</id>
<content type='text'>
[ Upstream commit 6d4341638516bf97b9a34947e0bd95035a8230a5 ]

Couple of Minor fixes:

- hcall return values are long. Fix that for h_get_mpp, h_get_ppp and
parse_ppp_data

- If hcall fails, values set should be at-least zero. It shouldn't be
uninitialized values. Fix that for h_get_mpp and h_get_ppp

Signed-off-by: Shrikanth Hegde &lt;sshegde@linux.ibm.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://msgid.link/20240412092047.455483-3-sshegde@linux.ibm.com
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 6d4341638516bf97b9a34947e0bd95035a8230a5 ]

Couple of Minor fixes:

- hcall return values are long. Fix that for h_get_mpp, h_get_ppp and
parse_ppp_data

- If hcall fails, values set should be at-least zero. It shouldn't be
uninitialized values. Fix that for h_get_mpp and h_get_ppp

Signed-off-by: Shrikanth Hegde &lt;sshegde@linux.ibm.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://msgid.link/20240412092047.455483-3-sshegde@linux.ibm.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc/fsl: Fix mfpmr build errors with newer binutils</title>
<updated>2024-04-13T10:51:24+00:00</updated>
<author>
<name>Michael Ellerman</name>
<email>mpe@ellerman.id.au</email>
</author>
<published>2024-02-29T12:25:19+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=4fc30a31e1b7a7fa32085f8bef62a02844f45b2c'/>
<id>4fc30a31e1b7a7fa32085f8bef62a02844f45b2c</id>
<content type='text'>
[ Upstream commit 5f491356b7149564ab22323ccce79c8d595bfd0c ]

Binutils 2.38 complains about the use of mfpmr when building
ppc6xx_defconfig:

    CC      arch/powerpc/kernel/pmc.o
  {standard input}: Assembler messages:
  {standard input}:45: Error: unrecognized opcode: `mfpmr'
  {standard input}:56: Error: unrecognized opcode: `mtpmr'

This is because by default the kernel is built with -mcpu=powerpc, and
the mt/mfpmr instructions are not defined.

It can be avoided by enabling CONFIG_E300C3_CPU, but just adding that to
the defconfig will leave open the possibility of randconfig failures.

So add machine directives around the mt/mfpmr instructions to tell
binutils how to assemble them.

Cc: stable@vger.kernel.org
Reported-by: Jan-Benedict Glaw &lt;jbglaw@lug-owl.de&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://msgid.link/20240229122521.762431-3-mpe@ellerman.id.au
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 5f491356b7149564ab22323ccce79c8d595bfd0c ]

Binutils 2.38 complains about the use of mfpmr when building
ppc6xx_defconfig:

    CC      arch/powerpc/kernel/pmc.o
  {standard input}: Assembler messages:
  {standard input}:45: Error: unrecognized opcode: `mfpmr'
  {standard input}:56: Error: unrecognized opcode: `mtpmr'

This is because by default the kernel is built with -mcpu=powerpc, and
the mt/mfpmr instructions are not defined.

It can be avoided by enabling CONFIG_E300C3_CPU, but just adding that to
the defconfig will leave open the possibility of randconfig failures.

So add machine directives around the mt/mfpmr instructions to tell
binutils how to assemble them.

Cc: stable@vger.kernel.org
Reported-by: Jan-Benedict Glaw &lt;jbglaw@lug-owl.de&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://msgid.link/20240229122521.762431-3-mpe@ellerman.id.au
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
