<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-dev/arch/parisc, branch master</title>
<subtitle>Linux kernel development work - see feature branches</subtitle>
<id>https://git.zx2c4.com/linux-dev/atom/arch/parisc?h=master</id>
<link rel='self' href='https://git.zx2c4.com/linux-dev/atom/arch/parisc?h=master'/>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/'/>
<updated>2022-10-31T14:37:14Z</updated>
<entry>
<title>parisc: Avoid printing the hardware path twice</title>
<updated>2022-10-31T14:37:14Z</updated>
<author>
<name>Helge Deller</name>
<email>deller@gmx.de</email>
</author>
<published>2022-10-28T16:12:49Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=2b6ae0962b421103feb41a80406732944b0665b3'/>
<id>urn:sha1:2b6ae0962b421103feb41a80406732944b0665b3</id>
<content type='text'>
Avoid that the hardware path is shown twice in the kernel log, and clean
up the output of the version numbers to show up in the same order as
they are listed in the hardware database in the hardware.c file.
Additionally, optimize the memory footprint of the hardware database
and mark some code as init code.

Fixes: cab56b51ec0e ("parisc: Fix device names in /proc/iomem")
Signed-off-by: Helge Deller &lt;deller@gmx.de&gt;
Cc: &lt;stable@vger.kernel.org&gt; # v4.9+
</content>
</entry>
<entry>
<title>parisc: Use signed char for hardware path in pdc.h</title>
<updated>2022-10-21T07:15:20Z</updated>
<author>
<name>Helge Deller</name>
<email>deller@gmx.de</email>
</author>
<published>2022-10-21T07:15:20Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=50f19697dd768d8b072cf7f12c0c99c7d31b67d8'/>
<id>urn:sha1:50f19697dd768d8b072cf7f12c0c99c7d31b67d8</id>
<content type='text'>
Clean up the struct for hardware_path and drop the struct device_path
with a proper assignment of bc[] and mod members as signed chars.

This patch prepares for the kbuild change from Jason A. Donenfeld to
treat char as always unsigned.

Signed-off-by: Helge Deller &lt;deller@gmx.de&gt;
Cc: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
</content>
</entry>
<entry>
<title>Merge tag 'random-6.1-rc1-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/crng/random</title>
<updated>2022-10-16T22:27:07Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2022-10-16T22:27:07Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=f1947d7c8a61db1cb0ef909a6512ede0b1f2115b'/>
<id>urn:sha1:f1947d7c8a61db1cb0ef909a6512ede0b1f2115b</id>
<content type='text'>
Pull more random number generator updates from Jason Donenfeld:
 "This time with some large scale treewide cleanups.

  The intent of this pull is to clean up the way callers fetch random
  integers. The current rules for doing this right are:

   - If you want a secure or an insecure random u64, use get_random_u64()

   - If you want a secure or an insecure random u32, use get_random_u32()

     The old function prandom_u32() has been deprecated for a while
     now and is just a wrapper around get_random_u32(). Same for
     get_random_int().

   - If you want a secure or an insecure random u16, use get_random_u16()

   - If you want a secure or an insecure random u8, use get_random_u8()

   - If you want secure or insecure random bytes, use get_random_bytes().

     The old function prandom_bytes() has been deprecated for a while
     now and has long been a wrapper around get_random_bytes()

   - If you want a non-uniform random u32, u16, or u8 bounded by a
     certain open interval maximum, use prandom_u32_max()

     I say "non-uniform", because it doesn't do any rejection sampling
     or divisions. Hence, it stays within the prandom_*() namespace, not
     the get_random_*() namespace.

     I'm currently investigating a "uniform" function for 6.2. We'll see
     what comes of that.

  By applying these rules uniformly, we get several benefits:

   - By using prandom_u32_max() with an upper-bound that the compiler
     can prove at compile-time is ≤65536 or ≤256, internally
     get_random_u16() or get_random_u8() is used, which wastes fewer
     batched random bytes, and hence has higher throughput.

   - By using prandom_u32_max() instead of %, when the upper-bound is
     not a constant, division is still avoided, because
     prandom_u32_max() uses a faster multiplication-based trick instead.

   - By using get_random_u16() or get_random_u8() in cases where the
     return value is intended to indeed be a u16 or a u8, we waste fewer
     batched random bytes, and hence have higher throughput.

  This series was originally done by hand while I was on an airplane
  without Internet. Later, Kees and I worked on retroactively figuring
  out what could be done with Coccinelle and what had to be done
  manually, and then we split things up based on that.

  So while this touches a lot of files, the actual amount of code that's
  hand fiddled is comfortably small"

* tag 'random-6.1-rc1-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/crng/random:
  prandom: remove unused functions
  treewide: use get_random_bytes() when possible
  treewide: use get_random_u32() when possible
  treewide: use get_random_{u8,u16}() when possible, part 2
  treewide: use get_random_{u8,u16}() when possible, part 1
  treewide: use prandom_u32_max() when possible, part 2
  treewide: use prandom_u32_max() when possible, part 1
</content>
</entry>
<entry>
<title>Merge tag 'parisc-for-6.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux</title>
<updated>2022-10-14T19:10:01Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2022-10-14T19:10:01Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=f2e44139f3e0edb8be8821fe4dc93afd7b034182'/>
<id>urn:sha1:f2e44139f3e0edb8be8821fe4dc93afd7b034182</id>
<content type='text'>
Pull parisc updates from Helge Deller:
 "Fixes:

   - When we added basic vDSO support in kernel 5.18 we introduced a bug
     which prevented a mmap() of graphic card memory. This is because we
     used the DMB (data memory break trap bit) page flag as special-bit,
     but missed to clear that bit when loading the TLB.

   - Graphics card memory size was not correctly aligned

   - Spelling fixes (from Colin Ian King)

  Enhancements:

   - PDC console (which uses firmware calls) now rewritten as early
     console

   - Reduced size of alternative tables"

* tag 'parisc-for-6.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  parisc: Fix spelling mistake "mis-match" -&gt; "mismatch" in eisa driver
  parisc: Fix userspace graphics card breakage due to pgtable special bit
  parisc: fbdev/stifb: Align graphics memory size to 4MB
  parisc: Convert PDC console to an early console
  parisc: Reduce kernel size by packing alternative tables
</content>
</entry>
<entry>
<title>parisc: Fix userspace graphics card breakage due to pgtable special bit</title>
<updated>2022-10-14T08:45:12Z</updated>
<author>
<name>Helge Deller</name>
<email>deller@gmx.de</email>
</author>
<published>2022-10-14T08:18:53Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=70be49f2f6223ddd2fcddb0089a40864c37e1494'/>
<id>urn:sha1:70be49f2f6223ddd2fcddb0089a40864c37e1494</id>
<content type='text'>
Commit df24e1783e6e ("parisc: Add vDSO support") introduced the vDSO
support, for which a _PAGE_SPECIAL page table flag was needed.  Since we
wanted to keep every page table entry in 32-bits, this patch re-used the
existing - but yet unused - _PAGE_DMB flag (which triggers a hardware break
if a page is accessed) to store the special bit.

But when graphics card memory is mmapped into userspace, the kernel uses
vm_iomap_memory() which sets the the special flag. So, with the DMB bit
set, every access to the graphics memory now triggered a hardware
exception and segfaulted the userspace program.

Fix this breakage by dropping the DMB bit when writing the page
protection bits to the CPU TLB.

In addition this patch adds a small optimization: if huge pages aren't
configured (which is at least the case for 32-bit kernels), then the
special bit is stored in the hpage (HUGE PAGE) bit instead. That way we
can skip to reset the DMB bit.

Fixes: df24e1783e6e ("parisc: Add vDSO support")
Cc: &lt;stable@vger.kernel.org&gt; # 5.18+
Signed-off-by: Helge Deller &lt;deller@gmx.de&gt;
</content>
</entry>
<entry>
<title>Merge tag 'mm-nonmm-stable-2022-10-11' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm</title>
<updated>2022-10-12T18:00:22Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2022-10-12T18:00:22Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=676cb4957396411fdb7aba906d5f950fc3de7cc9'/>
<id>urn:sha1:676cb4957396411fdb7aba906d5f950fc3de7cc9</id>
<content type='text'>
Pull non-MM updates from Andrew Morton:

 - hfs and hfsplus kmap API modernization (Fabio Francesco)

 - make crash-kexec work properly when invoked from an NMI-time panic
   (Valentin Schneider)

 - ntfs bugfixes (Hawkins Jiawei)

 - improve IPC msg scalability by replacing atomic_t's with percpu
   counters (Jiebin Sun)

 - nilfs2 cleanups (Minghao Chi)

 - lots of other single patches all over the tree!

* tag 'mm-nonmm-stable-2022-10-11' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (71 commits)
  include/linux/entry-common.h: remove has_signal comment of arch_do_signal_or_restart() prototype
  proc: test how it holds up with mapping'less process
  mailmap: update Frank Rowand email address
  ia64: mca: use strscpy() is more robust and safer
  init/Kconfig: fix unmet direct dependencies
  ia64: update config files
  nilfs2: replace WARN_ONs by nilfs_error for checkpoint acquisition failure
  fork: remove duplicate included header files
  init/main.c: remove unnecessary (void*) conversions
  proc: mark more files as permanent
  nilfs2: remove the unneeded result variable
  nilfs2: delete unnecessary checks before brelse()
  checkpatch: warn for non-standard fixes tag style
  usr/gen_init_cpio.c: remove unnecessary -1 values from int file
  ipc/msg: mitigate the lock contention with percpu counter
  percpu: add percpu_counter_add_local and percpu_counter_sub_local
  fs/ocfs2: fix repeated words in comments
  relay: use kvcalloc to alloc page array in relay_alloc_page_array
  proc: make config PROC_CHILDREN depend on PROC_FS
  fs: uninline inode_maybe_inc_iversion()
  ...
</content>
</entry>
<entry>
<title>treewide: use get_random_u32() when possible</title>
<updated>2022-10-11T23:42:58Z</updated>
<author>
<name>Jason A. Donenfeld</name>
<email>Jason@zx2c4.com</email>
</author>
<published>2022-10-05T15:43:22Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=a251c17aa558d8e3128a528af5cf8b9d7caae4fd'/>
<id>urn:sha1:a251c17aa558d8e3128a528af5cf8b9d7caae4fd</id>
<content type='text'>
The prandom_u32() function has been a deprecated inline wrapper around
get_random_u32() for several releases now, and compiles down to the
exact same code. Replace the deprecated wrapper with a direct call to
the real function. The same also applies to get_random_int(), which is
just a wrapper around get_random_u32(). This was done as a basic find
and replace.

Reviewed-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Reviewed-by: Kees Cook &lt;keescook@chromium.org&gt;
Reviewed-by: Yury Norov &lt;yury.norov@gmail.com&gt;
Reviewed-by: Jan Kara &lt;jack@suse.cz&gt; # for ext4
Acked-by: Toke Høiland-Jørgensen &lt;toke@toke.dk&gt; # for sch_cake
Acked-by: Chuck Lever &lt;chuck.lever@oracle.com&gt; # for nfsd
Acked-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Acked-by: Mika Westerberg &lt;mika.westerberg@linux.intel.com&gt; # for thunderbolt
Acked-by: Darrick J. Wong &lt;djwong@kernel.org&gt; # for xfs
Acked-by: Helge Deller &lt;deller@gmx.de&gt; # for parisc
Acked-by: Heiko Carstens &lt;hca@linux.ibm.com&gt; # for s390
Signed-off-by: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
</content>
</entry>
<entry>
<title>treewide: use prandom_u32_max() when possible, part 1</title>
<updated>2022-10-11T23:42:55Z</updated>
<author>
<name>Jason A. Donenfeld</name>
<email>Jason@zx2c4.com</email>
</author>
<published>2022-10-05T14:43:38Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=81895a65ec63ee1daec3255dc1a06675d2fbe915'/>
<id>urn:sha1:81895a65ec63ee1daec3255dc1a06675d2fbe915</id>
<content type='text'>
Rather than incurring a division or requesting too many random bytes for
the given range, use the prandom_u32_max() function, which only takes
the minimum required bytes from the RNG and avoids divisions. This was
done mechanically with this coccinelle script:

@basic@
expression E;
type T;
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
typedef u64;
@@
(
- ((T)get_random_u32() % (E))
+ prandom_u32_max(E)
|
- ((T)get_random_u32() &amp; ((E) - 1))
+ prandom_u32_max(E * XXX_MAKE_SURE_E_IS_POW2)
|
- ((u64)(E) * get_random_u32() &gt;&gt; 32)
+ prandom_u32_max(E)
|
- ((T)get_random_u32() &amp; ~PAGE_MASK)
+ prandom_u32_max(PAGE_SIZE)
)

@multi_line@
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
identifier RAND;
expression E;
@@

-       RAND = get_random_u32();
        ... when != RAND
-       RAND %= (E);
+       RAND = prandom_u32_max(E);

// Find a potential literal
@literal_mask@
expression LITERAL;
type T;
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
position p;
@@

        ((T)get_random_u32()@p &amp; (LITERAL))

// Add one to the literal.
@script:python add_one@
literal &lt;&lt; literal_mask.LITERAL;
RESULT;
@@

value = None
if literal.startswith('0x'):
        value = int(literal, 16)
elif literal[0] in '123456789':
        value = int(literal, 10)
if value is None:
        print("I don't know how to handle %s" % (literal))
        cocci.include_match(False)
elif value == 2**32 - 1 or value == 2**31 - 1 or value == 2**24 - 1 or value == 2**16 - 1 or value == 2**8 - 1:
        print("Skipping 0x%x for cleanup elsewhere" % (value))
        cocci.include_match(False)
elif value &amp; (value + 1) != 0:
        print("Skipping 0x%x because it's not a power of two minus one" % (value))
        cocci.include_match(False)
elif literal.startswith('0x'):
        coccinelle.RESULT = cocci.make_expr("0x%x" % (value + 1))
else:
        coccinelle.RESULT = cocci.make_expr("%d" % (value + 1))

// Replace the literal mask with the calculated result.
@plus_one@
expression literal_mask.LITERAL;
position literal_mask.p;
expression add_one.RESULT;
identifier FUNC;
@@

-       (FUNC()@p &amp; (LITERAL))
+       prandom_u32_max(RESULT)

@collapse_ret@
type T;
identifier VAR;
expression E;
@@

 {
-       T VAR;
-       VAR = (E);
-       return VAR;
+       return E;
 }

@drop_var@
type T;
identifier VAR;
@@

 {
-       T VAR;
        ... when != VAR
 }

Reviewed-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Reviewed-by: Kees Cook &lt;keescook@chromium.org&gt;
Reviewed-by: Yury Norov &lt;yury.norov@gmail.com&gt;
Reviewed-by: KP Singh &lt;kpsingh@kernel.org&gt;
Reviewed-by: Jan Kara &lt;jack@suse.cz&gt; # for ext4 and sbitmap
Reviewed-by: Christoph Böhmwalder &lt;christoph.boehmwalder@linbit.com&gt; # for drbd
Acked-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Acked-by: Heiko Carstens &lt;hca@linux.ibm.com&gt; # for s390
Acked-by: Ulf Hansson &lt;ulf.hansson@linaro.org&gt; # for mmc
Acked-by: Darrick J. Wong &lt;djwong@kernel.org&gt; # for xfs
Signed-off-by: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
</content>
</entry>
<entry>
<title>parisc: Convert PDC console to an early console</title>
<updated>2022-10-11T10:01:24Z</updated>
<author>
<name>Helge Deller</name>
<email>deller@gmx.de</email>
</author>
<published>2022-09-30T22:32:07Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=027c3d345e2a1ea61d6e4506a250eb392e6e7b18'/>
<id>urn:sha1:027c3d345e2a1ea61d6e4506a250eb392e6e7b18</id>
<content type='text'>
Rewrite the PDC console to become an early console.
Beside the fact that now boot information is visible until another
(text- or graphics) console takes over, this benefits as well machines
with a yet-unsupported STI console and kgdb.

Signed-off-by: Helge Deller &lt;deller@gmx.de&gt;
</content>
</entry>
<entry>
<title>parisc: Reduce kernel size by packing alternative tables</title>
<updated>2022-10-11T10:01:24Z</updated>
<author>
<name>Helge Deller</name>
<email>deller@gmx.de</email>
</author>
<published>2022-09-28T21:31:20Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=b148766e2b8b7b61c9aef53aefedae33f637a1e7'/>
<id>urn:sha1:b148766e2b8b7b61c9aef53aefedae33f637a1e7</id>
<content type='text'>
The values stored in the length and condition fields of the alternative
tables fit into 16 bits, so we can save 4 bytes per alternative table
entry.
Since a typical 32-bit kernel has more than 3000 entries this
saves &gt; 12k of storage on disc.

bloat-o-meter shows a reduction of -0.01% by this change:
Total: Before=10196505, After=10195529, chg -0.01%

$ ls -la vmlinux vmlinux.before
-rwxr-xr-x  14437324 vmlinux
-rwxr-xr-x  14449512 vmlinux.before

Signed-off-by: Helge Deller &lt;deller@gmx.de&gt;
</content>
</entry>
</feed>
