<feed xmlns='http://www.w3.org/2005/Atom'>
<title>user/sven/linux.git/drivers/firmware/efi, branch v4.18.2</title>
<subtitle>Linux Kernel
</subtitle>
<id>https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v4.18.2</id>
<link rel='self' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v4.18.2'/>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/'/>
<updated>2018-06-22T08:58:27Z</updated>
<entry>
<title>efi/libstub/tpm: Initialize efi_physical_addr_t vars to zero for mixed mode</title>
<updated>2018-06-22T08:58:27Z</updated>
<author>
<name>Hans de Goede</name>
<email>hdegoede@redhat.com</email>
</author>
<published>2018-06-22T06:42:22Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=52e1cf2d19c2e62e6a81b8de3f7320d033917dd5'/>
<id>urn:sha1:52e1cf2d19c2e62e6a81b8de3f7320d033917dd5</id>
<content type='text'>
Commit:

  79832f0b5f71 ("efi/libstub/tpm: Initialize pointer variables to zero for mixed mode")

fixes a problem with the tpm code on mixed mode (64-bit kernel on 32-bit UEFI),
where 64-bit pointer variables are not fully initialized by the 32-bit EFI code.

A similar problem applies to the efi_physical_addr_t variables which
are written by the -&gt;get_event_log() EFI call. Even though efi_physical_addr_t
is 64-bit everywhere, it seems that some 32-bit UEFI implementations only
fill in the lower 32 bits when passed a pointer to an efi_physical_addr_t
to fill.

This commit initializes these to 0 to, to ensure the upper 32 bits are
0 in mixed mode. This fixes recent kernels sometimes hanging during
early boot on mixed mode UEFI systems.

Signed-off-by: Hans de Goede &lt;hdegoede@redhat.com&gt;
Signed-off-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Cc: &lt;stable@vger.kernel.org&gt; # v4.16+
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20180622064222.11633-2-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</content>
</entry>
<entry>
<title>Merge branch 'akpm' (patches from Andrew)</title>
<updated>2018-06-14T23:51:42Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2018-06-14T23:51:42Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=b5d903c2d656e9bc54bc76554a477d796a63120d'/>
<id>urn:sha1:b5d903c2d656e9bc54bc76554a477d796a63120d</id>
<content type='text'>
Merge more updates from Andrew Morton:

 - MM remainders

 - various misc things

 - kcov updates

* emailed patches from Andrew Morton &lt;akpm@linux-foundation.org&gt;: (27 commits)
  lib/test_printf.c: call wait_for_random_bytes() before plain %p tests
  hexagon: drop the unused variable zero_page_mask
  hexagon: fix printk format warning in setup.c
  mm: fix oom_kill event handling
  treewide: use PHYS_ADDR_MAX to avoid type casting ULLONG_MAX
  mm: use octal not symbolic permissions
  ipc: use new return type vm_fault_t
  sysvipc/sem: mitigate semnum index against spectre v1
  fault-injection: reorder config entries
  arm: port KCOV to arm
  sched/core / kcov: avoid kcov_area during task switch
  kcov: prefault the kcov_area
  kcov: ensure irq code sees a valid area
  kernel/relay.c: change return type to vm_fault_t
  exofs: avoid VLA in structures
  coredump: fix spam with zero VMA process
  fat: use fat_fs_error() instead of BUG_ON() in __fat_get_block()
  proc: skip branch in /proc/*/* lookup
  mremap: remove LATENCY_LIMIT from mremap to reduce the number of TLB shootdowns
  mm/memblock: add missing include &lt;linux/bootmem.h&gt;
  ...
</content>
</entry>
<entry>
<title>treewide: use PHYS_ADDR_MAX to avoid type casting ULLONG_MAX</title>
<updated>2018-06-14T22:55:25Z</updated>
<author>
<name>Stefan Agner</name>
<email>stefan@agner.ch</email>
</author>
<published>2018-06-14T22:28:02Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=d7dc899abefb4412388a5d3ec690070197d07d20'/>
<id>urn:sha1:d7dc899abefb4412388a5d3ec690070197d07d20</id>
<content type='text'>
With PHYS_ADDR_MAX there is now a type safe variant for all bits set.
Make use of it.

Patch created using a semantic patch as follows:

// &lt;smpl&gt;
@@
typedef phys_addr_t;
@@
-(phys_addr_t)ULLONG_MAX
+PHYS_ADDR_MAX
// &lt;/smpl&gt;

Link: http://lkml.kernel.org/r/20180419214204.19322-1-stefan@agner.ch
Signed-off-by: Stefan Agner &lt;stefan@agner.ch&gt;
Reviewed-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Acked-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Acked-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;	[arm64]
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 tag 'vfs-timespec64' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground</title>
<updated>2018-06-14T22:31:07Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2018-06-14T22:31:07Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=7a932516f55cdf430c7cce78df2010ff7db6b874'/>
<id>urn:sha1:7a932516f55cdf430c7cce78df2010ff7db6b874</id>
<content type='text'>
Pull inode timestamps conversion to timespec64 from Arnd Bergmann:
 "This is a late set of changes from Deepa Dinamani doing an automated
  treewide conversion of the inode and iattr structures from 'timespec'
  to 'timespec64', to push the conversion from the VFS layer into the
  individual file systems.

  As Deepa writes:

   'The series aims to switch vfs timestamps to use struct timespec64.
    Currently vfs uses struct timespec, which is not y2038 safe.

    The series involves the following:
    1. Add vfs helper functions for supporting struct timepec64
       timestamps.
    2. Cast prints of vfs timestamps to avoid warnings after the switch.
    3. Simplify code using vfs timestamps so that the actual replacement
       becomes easy.
    4. Convert vfs timestamps to use struct timespec64 using a script.
       This is a flag day patch.

    Next steps:
    1. Convert APIs that can handle timespec64, instead of converting
       timestamps at the boundaries.
    2. Update internal data structures to avoid timestamp conversions'

  Thomas Gleixner adds:

   'I think there is no point to drag that out for the next merge
    window. The whole thing needs to be done in one go for the core
    changes which means that you're going to play that catchup game
    forever. Let's get over with it towards the end of the merge window'"

* tag 'vfs-timespec64' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground:
  pstore: Remove bogus format string definition
  vfs: change inode times to use struct timespec64
  pstore: Convert internal records to timespec64
  udf: Simplify calls to udf_disk_stamp_to_time
  fs: nfs: get rid of memcpys for inode times
  ceph: make inode time prints to be long long
  lustre: Use long long type to print inode time
  fs: add timespec64_truncate()
</content>
</entry>
<entry>
<title>treewide: kzalloc() -&gt; kcalloc()</title>
<updated>2018-06-12T23:19:22Z</updated>
<author>
<name>Kees Cook</name>
<email>keescook@chromium.org</email>
</author>
<published>2018-06-12T21:03:40Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=6396bb221514d2876fd6dc0aa2a1f240d99b37bb'/>
<id>urn:sha1:6396bb221514d2876fd6dc0aa2a1f240d99b37bb</id>
<content type='text'>
The kzalloc() function has a 2-factor argument form, kcalloc(). This
patch replaces cases of:

        kzalloc(a * b, gfp)

with:
        kcalloc(a * b, gfp)

as well as handling cases of:

        kzalloc(a * b * c, gfp)

with:

        kzalloc(array3_size(a, b, c), gfp)

as it's slightly less ugly than:

        kzalloc_array(array_size(a, b), c, gfp)

This does, however, attempt to ignore constant size factors like:

        kzalloc(4 * 1024, gfp)

though any constants defined via macros get caught up in the conversion.

Any factors with a sizeof() of "unsigned char", "char", and "u8" were
dropped, since they're redundant.

The Coccinelle script used for this was:

// Fix redundant parens around sizeof().
@@
type TYPE;
expression THING, E;
@@

(
  kzalloc(
-	(sizeof(TYPE)) * E
+	sizeof(TYPE) * E
  , ...)
|
  kzalloc(
-	(sizeof(THING)) * E
+	sizeof(THING) * E
  , ...)
)

// Drop single-byte sizes and redundant parens.
@@
expression COUNT;
typedef u8;
typedef __u8;
@@

(
  kzalloc(
-	sizeof(u8) * (COUNT)
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(__u8) * (COUNT)
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(char) * (COUNT)
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(unsigned char) * (COUNT)
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(u8) * COUNT
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(__u8) * COUNT
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(char) * COUNT
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(unsigned char) * COUNT
+	COUNT
  , ...)
)

// 2-factor product with sizeof(type/expression) and identifier or constant.
@@
type TYPE;
expression THING;
identifier COUNT_ID;
constant COUNT_CONST;
@@

(
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * (COUNT_ID)
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * COUNT_ID
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * (COUNT_CONST)
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * COUNT_CONST
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * (COUNT_ID)
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * COUNT_ID
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * (COUNT_CONST)
+	COUNT_CONST, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * COUNT_CONST
+	COUNT_CONST, sizeof(THING)
  , ...)
)

// 2-factor product, only identifiers.
@@
identifier SIZE, COUNT;
@@

- kzalloc
+ kcalloc
  (
-	SIZE * COUNT
+	COUNT, SIZE
  , ...)

// 3-factor product with 1 sizeof(type) or sizeof(expression), with
// redundant parens removed.
@@
expression THING;
identifier STRIDE, COUNT;
type TYPE;
@@

(
  kzalloc(
-	sizeof(TYPE) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kzalloc(
-	sizeof(TYPE) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kzalloc(
-	sizeof(TYPE) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kzalloc(
-	sizeof(TYPE) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kzalloc(
-	sizeof(THING) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kzalloc(
-	sizeof(THING) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kzalloc(
-	sizeof(THING) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kzalloc(
-	sizeof(THING) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
)

// 3-factor product with 2 sizeof(variable), with redundant parens removed.
@@
expression THING1, THING2;
identifier COUNT;
type TYPE1, TYPE2;
@@

(
  kzalloc(
-	sizeof(TYPE1) * sizeof(TYPE2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kzalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kzalloc(
-	sizeof(THING1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kzalloc(
-	sizeof(THING1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kzalloc(
-	sizeof(TYPE1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
|
  kzalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
)

// 3-factor product, only identifiers, with redundant parens removed.
@@
identifier STRIDE, SIZE, COUNT;
@@

(
  kzalloc(
-	(COUNT) * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	COUNT * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	COUNT * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	(COUNT) * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	COUNT * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	(COUNT) * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	(COUNT) * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	COUNT * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
)

// Any remaining multi-factor products, first at least 3-factor products,
// when they're not all constants...
@@
expression E1, E2, E3;
constant C1, C2, C3;
@@

(
  kzalloc(C1 * C2 * C3, ...)
|
  kzalloc(
-	(E1) * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kzalloc(
-	(E1) * (E2) * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kzalloc(
-	(E1) * (E2) * (E3)
+	array3_size(E1, E2, E3)
  , ...)
|
  kzalloc(
-	E1 * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
)

// And then all remaining 2 factors products when they're not all constants,
// keeping sizeof() as the second factor argument.
@@
expression THING, E1, E2;
type TYPE;
constant C1, C2, C3;
@@

(
  kzalloc(sizeof(THING) * C2, ...)
|
  kzalloc(sizeof(TYPE) * C2, ...)
|
  kzalloc(C1 * C2 * C3, ...)
|
  kzalloc(C1 * C2, ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * (E2)
+	E2, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * E2
+	E2, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * (E2)
+	E2, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * E2
+	E2, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	(E1) * E2
+	E1, E2
  , ...)
|
- kzalloc
+ kcalloc
  (
-	(E1) * (E2)
+	E1, E2
  , ...)
|
- kzalloc
+ kcalloc
  (
-	E1 * E2
+	E1, E2
  , ...)
)

Signed-off-by: Kees Cook &lt;keescook@chromium.org&gt;
</content>
</entry>
<entry>
<title>pstore: Convert internal records to timespec64</title>
<updated>2018-06-05T23:57:31Z</updated>
<author>
<name>Kees Cook</name>
<email>keescook@chromium.org</email>
</author>
<published>2018-05-14T22:50:52Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=7aaa822ed060719bd4ea012609883b6bc6950508'/>
<id>urn:sha1:7aaa822ed060719bd4ea012609883b6bc6950508</id>
<content type='text'>
This prepares pstore for converting the VFS layer to timespec64.

Signed-off-by: Kees Cook &lt;keescook@chromium.org&gt;
Signed-off-by: Deepa Dinamani &lt;deepa.kernel@gmail.com&gt;
</content>
</entry>
<entry>
<title>Merge tag 'dp-4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm</title>
<updated>2018-06-05T17:13:13Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2018-06-05T17:13:13Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=a74e0c4c9cb02d44bc5ec1a70a6ba599366fb130'/>
<id>urn:sha1:a74e0c4c9cb02d44bc5ec1a70a6ba599366fb130</id>
<content type='text'>
Pull device properties framework update from Rafael Wysocki:
 "Modify the device properties framework to remove union aliasing from
  it (Andy Shevchenko)"

* tag 'dp-4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  device property: Get rid of union aliasing
</content>
</entry>
<entry>
<title>Merge branch 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2018-06-04T23:31:06Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2018-06-04T23:31:06Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=31a85cb35c82d686a95f903fdf9a346aba818290'/>
<id>urn:sha1:31a85cb35c82d686a95f903fdf9a346aba818290</id>
<content type='text'>
Pull EFI updates from Ingo Molnar:

 - decode x86 CPER data (Yazen Ghannam)

 - ignore unrealistically large option ROMs (Hans de Goede)

 - initialize UEFI secure boot state during Xen dom0 boot (Daniel Kiper)

 - additional minor tweaks and fixes.

* 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  efi/capsule-loader: Don't output reset log when reset flags are not set
  efi/x86: Ignore unrealistically large option ROMs
  efi/x86: Fold __setup_efi_pci32() and __setup_efi_pci64() into one function
  efi: Align efi_pci_io_protocol typedefs to type naming convention
  efi/libstub/tpm: Make function efi_retrieve_tpm2_eventlog_1_2() static
  efi: Decode IA32/X64 Context Info structure
  efi: Decode IA32/X64 MS Check structure
  efi: Decode additional IA32/X64 Bus Check fields
  efi: Decode IA32/X64 Cache, TLB, and Bus Check structures
  efi: Decode UEFI-defined IA32/X64 Error Structure GUIDs
  efi: Decode IA32/X64 Processor Error Info Structure
  efi: Decode IA32/X64 Processor Error Section
  efi: Fix IA32/X64 Processor Error Record definition
  efi/cper: Remove the INDENT_SP silliness
  x86/xen/efi: Initialize UEFI secure boot state during dom0 boot
</content>
</entry>
<entry>
<title>efi/libstub/arm64: Handle randomized TEXT_OFFSET</title>
<updated>2018-05-19T06:07:56Z</updated>
<author>
<name>Mark Rutland</name>
<email>mark.rutland@arm.com</email>
</author>
<published>2018-05-18T14:08:41Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=4f74d72aa7067e75af92fbab077e6d7d0210be66'/>
<id>urn:sha1:4f74d72aa7067e75af92fbab077e6d7d0210be66</id>
<content type='text'>
When CONFIG_RANDOMIZE_TEXT_OFFSET=y, TEXT_OFFSET is an arbitrary
multiple of PAGE_SIZE in the interval [0, 2MB).

The EFI stub does not account for the potential misalignment of
TEXT_OFFSET relative to EFI_KIMG_ALIGN, and produces a randomized
physical offset which is always a round multiple of EFI_KIMG_ALIGN.
This may result in statically allocated objects whose alignment exceeds
PAGE_SIZE to appear misaligned in memory. This has been observed to
result in spurious stack overflow reports and failure to make use of
the IRQ stacks, and theoretically could result in a number of other
issues.

We can OR in the low bits of TEXT_OFFSET to ensure that we have the
necessary offset (and hence preserve the misalignment of TEXT_OFFSET
relative to EFI_KIMG_ALIGN), so let's do that.

Reported-by: Kim Phillips &lt;kim.phillips@arm.com&gt;
Tested-by: Kim Phillips &lt;kim.phillips@arm.com&gt;
[ardb: clarify comment and commit log, drop unneeded parens]
Signed-off-by: Mark Rutland &lt;mark.rutland@arm.com&gt;
Signed-off-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: linux-efi@vger.kernel.org
Fixes: 6f26b3671184c36d ("arm64: kaslr: increase randomization granularity")
Link: http://lkml.kernel.org/r/20180518140841.9731-2-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</content>
</entry>
<entry>
<title>device property: Get rid of union aliasing</title>
<updated>2018-05-17T10:47:21Z</updated>
<author>
<name>Andy Shevchenko</name>
<email>andriy.shevchenko@linux.intel.com</email>
</author>
<published>2018-05-15T17:32:02Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=63dcc7090137a893322432e156d66be3ce104615'/>
<id>urn:sha1:63dcc7090137a893322432e156d66be3ce104615</id>
<content type='text'>
Commit 318a19718261 (device property: refactor built-in properties
support) went way too far and brought a union aliasing. Partially
revert it here to get rid of union aliasing.

Note, all Apple properties are considered as u8 arrays. To get a value
of any of them the caller must use device_property_read_u8_array().

What's union aliasing?
~~~~~~~~~~~~~~~~~~~~~~

The C99 standard in section 6.2.5 paragraph 20 defines union type as
"an overlapping nonempty set of member objects". It also states in
section 6.7.2.1 paragraph 14 that "the value of at most one of the
members can be stored in a union object at any time'.

Union aliasing is a type punning mechanism using union members to store
as one type and read back as another.

Why it's not good?
~~~~~~~~~~~~~~~~~~

Section 6.2.6.1 paragraph 6 says that a union object may not be a trap
representation, although its member objects may be.

Meanwhile annex J.1 says that "the value of a union member other than
the last one stored into" is unspecified [removed in C11].

In TC3, a footnote is added which specifies that accessing a member of a
union other than the last one stored causes "the object representation"
to be re-interpreted in the new type and specifically refers to this as
"type punning". This conflicts to some degree with Annex J.1.

While it's working in Linux with GCC, the use of union members to do
type punning is not clear area in the C standard and might lead to
unspecified behaviour.

More information is available in this [1] blog post.

[1]: https://davmac.wordpress.com/2010/02/26/c99-revisited/

Signed-off-by: Andy Shevchenko &lt;andriy.shevchenko@linux.intel.com&gt;
Acked-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Reviewed-by: Mika Westerberg &lt;mika.westerberg@linux.intel.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</content>
</entry>
</feed>
