<feed xmlns='http://www.w3.org/2005/Atom'>
<title>kernel/linux.git/arch/arm64/include/asm/cache.h, branch v5.15.210</title>
<subtitle>Linux kernel stable tree (mirror)</subtitle>
<id>https://git.radix-linux.su/kernel/linux.git/atom?h=v5.15.210</id>
<link rel='self' href='https://git.radix-linux.su/kernel/linux.git/atom?h=v5.15.210'/>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/'/>
<updated>2021-07-12T12:37:34+00:00</updated>
<entry>
<title>Revert "arm64: cache: Lower ARCH_DMA_MINALIGN to 64 (L1_CACHE_BYTES)"</title>
<updated>2021-07-12T12:37:34+00:00</updated>
<author>
<name>Will Deacon</name>
<email>will@kernel.org</email>
</author>
<published>2021-07-12T12:10:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=c1132702c71f4b95db9435bac5fdc912881563e0'/>
<id>urn:sha1:c1132702c71f4b95db9435bac5fdc912881563e0</id>
<content type='text'>
This reverts commit 65688d2a05deb9f0671a7e2301eadbfe7e27c9e9.

Unfortunately, the original Qualcomm Kryo cores integrated into the
MSM8996 SoC feature an L2 cache with 128-byte lines which sits above
the Point of Coherency. Consequently, we must restore ARCH_DMA_MINALIGN
to its former ugly self so that non-coherent DMA can be performed safely
on devices built using this SoC.

Thanks to Jeffrey Hugo for confirming this with a hardware designer.

Link: https://lore.kernel.org/r/CAOCk7NqdpUZFMSXfGjw0_1NaSK5gyTLgpS9kSdZn1jmBy-QkfA@mail.gmail.com/
Reported-by: Yassine Oudjana &lt;y.oudjana@protonmail.com&gt;
Link: https://lore.kernel.org/r/uHgsRacR8hJ7nW-I-pIcehzg-lNIn7NJvaL7bP9tfAftFsBjsgaY2qTjG9zyBgxHkjNL1WPNrD7YVv2JVD2_Wy-a5VTbcq-1xEi8ZnwrXBo=@protonmail.com
Signed-off-by: Will Deacon &lt;will@kernel.org&gt;
</content>
</entry>
<entry>
<title>arm64: cache: Lower ARCH_DMA_MINALIGN to 64 (L1_CACHE_BYTES)</title>
<updated>2021-06-01T17:55:33+00:00</updated>
<author>
<name>Will Deacon</name>
<email>will@kernel.org</email>
</author>
<published>2021-05-27T12:43:56+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=65688d2a05deb9f0671a7e2301eadbfe7e27c9e9'/>
<id>urn:sha1:65688d2a05deb9f0671a7e2301eadbfe7e27c9e9</id>
<content type='text'>
Back in 97303480753e ("arm64: Increase the max granular size"),
ARCH_DMA_MINALIGN was effectively increased to 128 bytes thanks to an
increase in L1_CACHE_BYTES due to an unsubstantiated performance claim
on the now obsolete ThunderX-1. Although this was reverted in
d93277b9839b, ARCH_DMA_MINALIGN was kept at 128 bytes by ebc7e21e0fa2
("arm64: Increase ARCH_DMA_MINALIGN to 128").

During discussion of the original patch, it was reported that the change
also prevented a warning during boot on (again, now obsolete) Qualcomm
server hardware where the cache writeback granule was larger than 64
bytes. The reason for this warning was because non-coherent DMA could
lead to data corruption due to unexpected writeback from the CPU where a
cacheline is shared with other allocations.

Since then, systems have appeared with larger cachelines still, and so
commit 8f5c9037a55b ("arm64/mm: Correct the cache line size warning with
non coherent device") reworked the warning so that it only appears on
systems where non-coherent DMA is actually required and taints the
kernel with TAINT_CPU_OUT_OF_SPEC. We are not aware of any systems, even
including the aforementioned obsolete machines, which have a CWG larger
than 64 bytes and require non-coherent DMA.

More recently, it has been reported that a ARCH_DMA_MINALIGN of 128
bytes wastes considerable memory (~6% immediately after boot on one
system).

Reduce ARCH_DMA_MINALIGN to 64 bytes and allow the warning/taint to
indicate if there are machines that unknowingly rely on this.

Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Ard Biesheuvel &lt;ardb@kernel.org&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: Vincent Whitchurch &lt;vincent.whitchurch@axis.com&gt;
Link: https://lore.kernel.org/linux-arm-kernel/1442944788-17254-1-git-send-email-rric@kernel.org/
Link: https://lore.kernel.org/linux-arm-kernel/CAOZdJXUiRMAguDV+HEJqPg57MyBNqEcTyaH+ya=U93NHb-pdJA@mail.gmail.com/
Link: https://lore.kernel.org/linux-arm-kernel/20190614131141.4428-1-msys.mizuma@gmail.com/
Link: https://lore.kernel.org/r/20210517074332.28280-1-vincent.whitchurch@axis.com
Acked-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Acked-by: Mark Rutland &lt;mark.rutland@arm.com&gt;
Acked-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Acked-by: Mark Rutland &lt;mark.rutland@arm.com&gt;
Acked-by: Ard Biesheuvel &lt;ardb@kernel.org&gt;
Link: https://lore.kernel.org/r/20210527124356.22367-1-will@kernel.org
Signed-off-by: Will Deacon &lt;will@kernel.org&gt;
</content>
</entry>
<entry>
<title>arm64: kasan: simplify and inline MTE functions</title>
<updated>2021-02-26T17:41:03+00:00</updated>
<author>
<name>Andrey Konovalov</name>
<email>andreyknvl@google.com</email>
</author>
<published>2021-02-26T01:20:31+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=2cb34276427a093e2d7cc6ea63ac447bad1ff4c1'/>
<id>urn:sha1:2cb34276427a093e2d7cc6ea63ac447bad1ff4c1</id>
<content type='text'>
This change provides a simpler implementation of mte_get_mem_tag(),
mte_get_random_tag(), and mte_set_mem_tag_range().

Simplifications include removing system_supports_mte() checks as these
functions are onlye called from KASAN runtime that had already checked
system_supports_mte().  Besides that, size and address alignment checks
are removed from mte_set_mem_tag_range(), as KASAN now does those.

This change also moves these functions into the asm/mte-kasan.h header and
implements mte_set_mem_tag_range() via inline assembly to avoid
unnecessary functions calls.

[vincenzo.frascino@arm.com: fix warning in mte_get_random_tag()]
  Link: https://lkml.kernel.org/r/20210211152208.23811-1-vincenzo.frascino@arm.com

Link: https://lkml.kernel.org/r/a26121b294fdf76e369cb7a74351d1c03a908930.1612546384.git.andreyknvl@google.com
Co-developed-by: Vincenzo Frascino &lt;vincenzo.frascino@arm.com&gt;
Signed-off-by: Vincenzo Frascino &lt;vincenzo.frascino@arm.com&gt;
Signed-off-by: Andrey Konovalov &lt;andreyknvl@google.com&gt;
Reviewed-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Alexander Potapenko &lt;glider@google.com&gt;
Cc: Andrey Ryabinin &lt;aryabinin@virtuozzo.com&gt;
Cc: Branislav Rankov &lt;Branislav.Rankov@arm.com&gt;
Cc: Dmitry Vyukov &lt;dvyukov@google.com&gt;
Cc: Evgenii Stepanov &lt;eugenis@google.com&gt;
Cc: Kevin Brodsky &lt;kevin.brodsky@arm.com&gt;
Cc: Marco Elver &lt;elver@google.com&gt;
Cc: Peter Collingbourne &lt;pcc@google.com&gt;
Cc: Will Deacon &lt;will.deacon@arm.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>
<entry>
<title>arm64: kasan: align allocations for HW_TAGS</title>
<updated>2020-12-22T20:55:08+00:00</updated>
<author>
<name>Andrey Konovalov</name>
<email>andreyknvl@google.com</email>
</author>
<published>2020-12-22T20:01:52+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=dc09b29fd0718300fad79d327d275b6ffb6d3315'/>
<id>urn:sha1:dc09b29fd0718300fad79d327d275b6ffb6d3315</id>
<content type='text'>
Hardware tag-based KASAN uses the memory tagging approach, which requires
all allocations to be aligned to the memory granule size.  Align the
allocations to MTE_GRANULE_SIZE via ARCH_SLAB_MINALIGN when
CONFIG_KASAN_HW_TAGS is enabled.

Link: https://lkml.kernel.org/r/fe64131606b1c2aabfd34ae99554c0d9df18eb19.1606161801.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov &lt;andreyknvl@google.com&gt;
Signed-off-by: Vincenzo Frascino &lt;vincenzo.frascino@arm.com&gt;
Reviewed-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Reviewed-by: Alexander Potapenko &lt;glider@google.com&gt;
Tested-by: Vincenzo Frascino &lt;vincenzo.frascino@arm.com&gt;
Cc: Andrey Ryabinin &lt;aryabinin@virtuozzo.com&gt;
Cc: Branislav Rankov &lt;Branislav.Rankov@arm.com&gt;
Cc: Dmitry Vyukov &lt;dvyukov@google.com&gt;
Cc: Evgenii Stepanov &lt;eugenis@google.com&gt;
Cc: Kevin Brodsky &lt;kevin.brodsky@arm.com&gt;
Cc: Marco Elver &lt;elver@google.com&gt;
Cc: Vasily Gorbik &lt;gor@linux.ibm.com&gt;
Cc: Will Deacon &lt;will.deacon@arm.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>
<entry>
<title>arm64: avoid -Woverride-init warning</title>
<updated>2020-10-28T13:38:36+00:00</updated>
<author>
<name>Arnd Bergmann</name>
<email>arnd@arndb.de</email>
</author>
<published>2020-10-26T19:37:46+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=332576e69a046b9b33f49bd0c3c071cc98215b60'/>
<id>urn:sha1:332576e69a046b9b33f49bd0c3c071cc98215b60</id>
<content type='text'>
The icache_policy_str[] definition causes a warning when extra
warning flags are enabled:

arch/arm64/kernel/cpuinfo.c:38:26: warning: initialized field overwritten [-Woverride-init]
   38 |  [ICACHE_POLICY_VIPT]  = "VIPT",
      |                          ^~~~~~
arch/arm64/kernel/cpuinfo.c:38:26: note: (near initialization for 'icache_policy_str[2]')
arch/arm64/kernel/cpuinfo.c:39:26: warning: initialized field overwritten [-Woverride-init]
   39 |  [ICACHE_POLICY_PIPT]  = "PIPT",
      |                          ^~~~~~
arch/arm64/kernel/cpuinfo.c:39:26: note: (near initialization for 'icache_policy_str[3]')
arch/arm64/kernel/cpuinfo.c:40:27: warning: initialized field overwritten [-Woverride-init]
   40 |  [ICACHE_POLICY_VPIPT]  = "VPIPT",
      |                           ^~~~~~~
arch/arm64/kernel/cpuinfo.c:40:27: note: (near initialization for 'icache_policy_str[0]')

There is no real need for the default initializer here, as printing a
NULL string is harmless. Rewrite the logic to have an explicit
reserved value for the only one that uses the default value.

This partially reverts the commit that removed ICACHE_POLICY_AIVIVT.

Fixes: 155433cb365e ("arm64: cache: Remove support for ASID-tagged VIVT I-caches")
Signed-off-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Link: https://lore.kernel.org/r/20201026193807.3816388-1-arnd@kernel.org
Signed-off-by: Will Deacon &lt;will@kernel.org&gt;
</content>
</entry>
<entry>
<title>treewide: Convert macro and uses of __section(foo) to __section("foo")</title>
<updated>2020-10-25T21:51:49+00:00</updated>
<author>
<name>Joe Perches</name>
<email>joe@perches.com</email>
</author>
<published>2020-10-22T02:36:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=33def8498fdde180023444b08e12b72a9efed41d'/>
<id>urn:sha1:33def8498fdde180023444b08e12b72a9efed41d</id>
<content type='text'>
Use a more generic form for __section that requires quotes to avoid
complications with clang and gcc differences.

Remove the quote operator # from compiler_attributes.h __section macro.

Convert all unquoted __section(foo) uses to quoted __section("foo").
Also convert __attribute__((section("foo"))) uses to __section("foo")
even if the __attribute__ has multiple list entry forms.

Conversion done using the script at:

    https://lore.kernel.org/lkml/75393e5ddc272dc7403de74d645e6c6e0f4e70eb.camel@perches.com/2-convert_section.pl

Signed-off-by: Joe Perches &lt;joe@perches.com&gt;
Reviewed-by: Nick Desaulniers &lt;ndesaulniers@gooogle.com&gt;
Reviewed-by: Miguel Ojeda &lt;ojeda@kernel.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>arm64: Ask the compiler to __always_inline functions used by KVM at HYP</title>
<updated>2020-02-22T11:01:47+00:00</updated>
<author>
<name>James Morse</name>
<email>james.morse@arm.com</email>
</author>
<published>2020-02-20T16:58:39+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=e43f1331e2ef913b8c566920c9af75e0ccdd1d3f'/>
<id>urn:sha1:e43f1331e2ef913b8c566920c9af75e0ccdd1d3f</id>
<content type='text'>
KVM uses some of the static-inline helpers like icache_is_vipt() from
its HYP code. This assumes the function is inlined so that the code is
mapped to EL2. The compiler may decide not to inline these, and the
out-of-line version may not be in the __hyp_text section.

Add the additional __always_ hint to these static-inlines that are used
by KVM.

Signed-off-by: James Morse &lt;james.morse@arm.com&gt;
Signed-off-by: Marc Zyngier &lt;maz@kernel.org&gt;
Acked-by: Will Deacon &lt;will@kernel.org&gt;
Link: https://lore.kernel.org/r/20200220165839.256881-4-james.morse@arm.com
</content>
</entry>
<entry>
<title>arm64: Fake the IminLine size on systems affected by Neoverse-N1 #1542419</title>
<updated>2019-10-25T16:48:44+00:00</updated>
<author>
<name>James Morse</name>
<email>james.morse@arm.com</email>
</author>
<published>2019-10-17T17:42:59+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=ee9d90be9ddace01b7fb126567e4b539fbe1f82f'/>
<id>urn:sha1:ee9d90be9ddace01b7fb126567e4b539fbe1f82f</id>
<content type='text'>
Systems affected by Neoverse-N1 #1542419 support DIC so do not need to
perform icache maintenance once new instructions are cleaned to the PoU.
For the errata workaround, the kernel hides DIC from user-space, so that
the unnecessary cache maintenance can be trapped by firmware.

To reduce the number of traps, produce a fake IminLine value based on
PAGE_SIZE.

Signed-off-by: James Morse &lt;james.morse@arm.com&gt;
Reviewed-by: Suzuki K Poulose &lt;suzuki.poulose@arm.com&gt;
Signed-off-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
</content>
</entry>
<entry>
<title>arm64: prefer __section from compiler_attributes.h</title>
<updated>2019-08-13T17:32:15+00:00</updated>
<author>
<name>Nick Desaulniers</name>
<email>ndesaulniers@google.com</email>
</author>
<published>2019-08-12T21:50:45+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=80d838122643a09a9f99824adea4b4261e4451e6'/>
<id>urn:sha1:80d838122643a09a9f99824adea4b4261e4451e6</id>
<content type='text'>
GCC unescapes escaped string section names while Clang does not. Because
__section uses the `#` stringification operator for the section name, it
doesn't need to be escaped.

This antipattern was found with:
$ grep -e __section\(\" -e __section__\(\" -r

Reported-by: Sedat Dilek &lt;sedat.dilek@gmail.com&gt;
Suggested-by: Josh Poimboeuf &lt;jpoimboe@redhat.com&gt;
Signed-off-by: Nick Desaulniers &lt;ndesaulniers@google.com&gt;
Signed-off-by: Will Deacon &lt;will@kernel.org&gt;
</content>
</entry>
<entry>
<title>Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux</title>
<updated>2019-07-08T16:54:55+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2019-07-08T16:54:55+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=dfd437a257924484b144ee750e60affc95562c6d'/>
<id>urn:sha1:dfd437a257924484b144ee750e60affc95562c6d</id>
<content type='text'>
Pull arm64 updates from Catalin Marinas:

 - arm64 support for syscall emulation via PTRACE_SYSEMU{,_SINGLESTEP}

 - Wire up VM_FLUSH_RESET_PERMS for arm64, allowing the core code to
   manage the permissions of executable vmalloc regions more strictly

 - Slight performance improvement by keeping softirqs enabled while
   touching the FPSIMD/SVE state (kernel_neon_begin/end)

 - Expose a couple of ARMv8.5 features to user (HWCAP): CondM (new
   XAFLAG and AXFLAG instructions for floating point comparison flags
   manipulation) and FRINT (rounding floating point numbers to integers)

 - Re-instate ARM64_PSEUDO_NMI support which was previously marked as
   BROKEN due to some bugs (now fixed)

 - Improve parking of stopped CPUs and implement an arm64-specific
   panic_smp_self_stop() to avoid warning on not being able to stop
   secondary CPUs during panic

 - perf: enable the ARM Statistical Profiling Extensions (SPE) on ACPI
   platforms

 - perf: DDR performance monitor support for iMX8QXP

 - cache_line_size() can now be set from DT or ACPI/PPTT if provided to
   cope with a system cache info not exposed via the CPUID registers

 - Avoid warning on hardware cache line size greater than
   ARCH_DMA_MINALIGN if the system is fully coherent

 - arm64 do_page_fault() and hugetlb cleanups

 - Refactor set_pte_at() to avoid redundant READ_ONCE(*ptep)

 - Ignore ACPI 5.1 FADTs reported as 5.0 (infer from the
   'arm_boot_flags' introduced in 5.1)

 - CONFIG_RANDOMIZE_BASE now enabled in defconfig

 - Allow the selection of ARM64_MODULE_PLTS, currently only done via
   RANDOMIZE_BASE (and an erratum workaround), allowing modules to spill
   over into the vmalloc area

 - Make ZONE_DMA32 configurable

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (54 commits)
  perf: arm_spe: Enable ACPI/Platform automatic module loading
  arm_pmu: acpi: spe: Add initial MADT/SPE probing
  ACPI/PPTT: Add function to return ACPI 6.3 Identical tokens
  ACPI/PPTT: Modify node flag detection to find last IDENTICAL
  x86/entry: Simplify _TIF_SYSCALL_EMU handling
  arm64: rename dump_instr as dump_kernel_instr
  arm64/mm: Drop [PTE|PMD]_TYPE_FAULT
  arm64: Implement panic_smp_self_stop()
  arm64: Improve parking of stopped CPUs
  arm64: Expose FRINT capabilities to userspace
  arm64: Expose ARMv8.5 CondM capability to userspace
  arm64: defconfig: enable CONFIG_RANDOMIZE_BASE
  arm64: ARM64_MODULES_PLTS must depend on MODULES
  arm64: bpf: do not allocate executable memory
  arm64/kprobes: set VM_FLUSH_RESET_PERMS on kprobe instruction pages
  arm64/mm: wire up CONFIG_ARCH_HAS_SET_DIRECT_MAP
  arm64: module: create module allocations without exec permissions
  arm64: Allow user selection of ARM64_MODULE_PLTS
  acpi/arm64: ignore 5.1 FADTs that are reported as 5.0
  arm64: Allow selecting Pseudo-NMI again
  ...
</content>
</entry>
</feed>
