<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-dev/arch/x86/boot, branch master</title>
<subtitle>Linux kernel development work - see feature branches</subtitle>
<id>https://git.zx2c4.com/linux-dev/atom/arch/x86/boot?h=master</id>
<link rel='self' href='https://git.zx2c4.com/linux-dev/atom/arch/x86/boot?h=master'/>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/'/>
<updated>2022-10-11T00:53:04Z</updated>
<entry>
<title>Merge tag 'mm-stable-2022-10-08' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm</title>
<updated>2022-10-11T00:53:04Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2022-10-11T00:53:04Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=27bc50fc90647bbf7b734c3fc306a5e61350da53'/>
<id>urn:sha1:27bc50fc90647bbf7b734c3fc306a5e61350da53</id>
<content type='text'>
Pull MM updates from Andrew Morton:

 - Yu Zhao's Multi-Gen LRU patches are here. They've been under test in
   linux-next for a couple of months without, to my knowledge, any
   negative reports (or any positive ones, come to that).

 - Also the Maple Tree from Liam Howlett. An overlapping range-based
   tree for vmas. It it apparently slightly more efficient in its own
   right, but is mainly targeted at enabling work to reduce mmap_lock
   contention.

   Liam has identified a number of other tree users in the kernel which
   could be beneficially onverted to mapletrees.

   Yu Zhao has identified a hard-to-hit but "easy to fix" lockdep splat
   at [1]. This has yet to be addressed due to Liam's unfortunately
   timed vacation. He is now back and we'll get this fixed up.

 - Dmitry Vyukov introduces KMSAN: the Kernel Memory Sanitizer. It uses
   clang-generated instrumentation to detect used-unintialized bugs down
   to the single bit level.

   KMSAN keeps finding bugs. New ones, as well as the legacy ones.

 - Yang Shi adds a userspace mechanism (madvise) to induce a collapse of
   memory into THPs.

 - Zach O'Keefe has expanded Yang Shi's madvise(MADV_COLLAPSE) to
   support file/shmem-backed pages.

 - userfaultfd updates from Axel Rasmussen

 - zsmalloc cleanups from Alexey Romanov

 - cleanups from Miaohe Lin: vmscan, hugetlb_cgroup, hugetlb and
   memory-failure

 - Huang Ying adds enhancements to NUMA balancing memory tiering mode's
   page promotion, with a new way of detecting hot pages.

 - memcg updates from Shakeel Butt: charging optimizations and reduced
   memory consumption.

 - memcg cleanups from Kairui Song.

 - memcg fixes and cleanups from Johannes Weiner.

 - Vishal Moola provides more folio conversions

 - Zhang Yi removed ll_rw_block() :(

 - migration enhancements from Peter Xu

 - migration error-path bugfixes from Huang Ying

 - Aneesh Kumar added ability for a device driver to alter the memory
   tiering promotion paths. For optimizations by PMEM drivers, DRM
   drivers, etc.

 - vma merging improvements from Jakub Matěn.

 - NUMA hinting cleanups from David Hildenbrand.

 - xu xin added aditional userspace visibility into KSM merging
   activity.

 - THP &amp; KSM code consolidation from Qi Zheng.

 - more folio work from Matthew Wilcox.

 - KASAN updates from Andrey Konovalov.

 - DAMON cleanups from Kaixu Xia.

 - DAMON work from SeongJae Park: fixes, cleanups.

 - hugetlb sysfs cleanups from Muchun Song.

 - Mike Kravetz fixes locking issues in hugetlbfs and in hugetlb core.

Link: https://lkml.kernel.org/r/CAOUHufZabH85CeUN-MEMgL8gJGzJEWUrkiM58JkTbBhh-jew0Q@mail.gmail.com [1]

* tag 'mm-stable-2022-10-08' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (555 commits)
  hugetlb: allocate vma lock for all sharable vmas
  hugetlb: take hugetlb vma_lock when clearing vma_lock-&gt;vma pointer
  hugetlb: fix vma lock handling during split vma and range unmapping
  mglru: mm/vmscan.c: fix imprecise comments
  mm/mglru: don't sync disk for each aging cycle
  mm: memcontrol: drop dead CONFIG_MEMCG_SWAP config symbol
  mm: memcontrol: use do_memsw_account() in a few more places
  mm: memcontrol: deprecate swapaccounting=0 mode
  mm: memcontrol: don't allocate cgroup swap arrays when memcg is disabled
  mm/secretmem: remove reduntant return value
  mm/hugetlb: add available_huge_pages() func
  mm: remove unused inline functions from include/linux/mm_inline.h
  selftests/vm: add selftest for MADV_COLLAPSE of uffd-minor memory
  selftests/vm: add file/shmem MADV_COLLAPSE selftest for cleared pmd
  selftests/vm: add thp collapse shmem testing
  selftests/vm: add thp collapse file and tmpfs testing
  selftests/vm: modularize thp collapse memory operations
  selftests/vm: dedup THP helpers
  mm/khugepaged: add tracepoint to hpage_collapse_scan_file()
  mm/madvise: add file and shmem support to MADV_COLLAPSE
  ...
</content>
</entry>
<entry>
<title>Merge tag 'kbuild-v6.1' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild</title>
<updated>2022-10-10T19:00:45Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2022-10-10T19:00:45Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=8afc66e8d43be8edcf442165b70d50dd33091e68'/>
<id>urn:sha1:8afc66e8d43be8edcf442165b70d50dd33091e68</id>
<content type='text'>
Pull Kbuild updates from Masahiro Yamada:

 - Remove potentially incomplete targets when Kbuid is interrupted by
   SIGINT etc in case GNU Make may miss to do that when stderr is piped
   to another program.

 - Rewrite the single target build so it works more correctly.

 - Fix rpm-pkg builds with V=1.

 - List top-level subdirectories in ./Kbuild.

 - Ignore auto-generated __kstrtab_* and __kstrtabns_* symbols in
   kallsyms.

 - Avoid two different modules in lib/zstd/ having shared code, which
   potentially causes building the common code as build-in and modular
   back-and-forth.

 - Unify two modpost invocations to optimize the build process.

 - Remove head-y syntax in favor of linker scripts for placing
   particular sections in the head of vmlinux.

 - Bump the minimal GNU Make version to 3.82.

 - Clean up misc Makefiles and scripts.

* tag 'kbuild-v6.1' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (41 commits)
  docs: bump minimal GNU Make version to 3.82
  ia64: simplify esi object addition in Makefile
  Revert "kbuild: Check if linker supports the -X option"
  kbuild: rebuild .vmlinux.export.o when its prerequisite is updated
  kbuild: move modules.builtin(.modinfo) rules to Makefile.vmlinux_o
  zstd: Fixing mixed module-builtin objects
  kallsyms: ignore __kstrtab_* and __kstrtabns_* symbols
  kallsyms: take the input file instead of reading stdin
  kallsyms: drop duplicated ignore patterns from kallsyms.c
  kbuild: reuse mksysmap output for kallsyms
  mksysmap: update comment about __crc_*
  kbuild: remove head-y syntax
  kbuild: use obj-y instead extra-y for objects placed at the head
  kbuild: hide error checker logs for V=1 builds
  kbuild: re-run modpost when it is updated
  kbuild: unify two modpost invocations
  kbuild: move vmlinux.o rule to the top Makefile
  kbuild: move .vmlinux.objs rule to Makefile.modpost
  kbuild: list sub-directories in ./Kbuild
  Makefile.compiler: replace cc-ifversion with compiler-specific macros
  ...
</content>
</entry>
<entry>
<title>Merge tag 'x86_cleanups_for_v6.1_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2022-10-04T17:24:11Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2022-10-04T17:24:11Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=3eba620e7bd772a0c7dc91966cb107872b54a910'/>
<id>urn:sha1:3eba620e7bd772a0c7dc91966cb107872b54a910</id>
<content type='text'>
Pull x86 cleanups from Borislav Petkov:

 - The usual round of smaller fixes and cleanups all over the tree

* tag 'x86_cleanups_for_v6.1_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/cpu: Include the header of init_ia32_feat_ctl()'s prototype
  x86/uaccess: Improve __try_cmpxchg64_user_asm() for x86_32
  x86: Fix various duplicate-word comment typos
  x86/boot: Remove superfluous type casting from arch/x86/boot/bitops.h
</content>
</entry>
<entry>
<title>x86: kmsan: disable instrumentation of unsupported code</title>
<updated>2022-10-03T21:03:24Z</updated>
<author>
<name>Alexander Potapenko</name>
<email>glider@google.com</email>
</author>
<published>2022-09-15T15:04:06Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=93324e6842148cfdb44d1437fb586b957ace1f8c'/>
<id>urn:sha1:93324e6842148cfdb44d1437fb586b957ace1f8c</id>
<content type='text'>
Instrumenting some files with KMSAN will result in kernel being unable to
link, boot or crashing at runtime for various reasons (e.g.  infinite
recursion caused by instrumentation hooks calling instrumented code
again).

Completely omit KMSAN instrumentation in the following places:
 - arch/x86/boot and arch/x86/realmode/rm, as KMSAN doesn't work for i386;
 - arch/x86/entry/vdso, which isn't linked with KMSAN runtime;
 - three files in arch/x86/kernel - boot problems;
 - arch/x86/mm/cpu_entry_area.c - recursion.

Link: https://lkml.kernel.org/r/20220915150417.722975-33-glider@google.com
Signed-off-by: Alexander Potapenko &lt;glider@google.com&gt;
Cc: Alexander Viro &lt;viro@zeniv.linux.org.uk&gt;
Cc: Alexei Starovoitov &lt;ast@kernel.org&gt;
Cc: Andrey Konovalov &lt;andreyknvl@gmail.com&gt;
Cc: Andrey Konovalov &lt;andreyknvl@google.com&gt;
Cc: Andy Lutomirski &lt;luto@kernel.org&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: Christoph Hellwig &lt;hch@lst.de&gt;
Cc: Christoph Lameter &lt;cl@linux.com&gt;
Cc: David Rientjes &lt;rientjes@google.com&gt;
Cc: Dmitry Vyukov &lt;dvyukov@google.com&gt;
Cc: Eric Biggers &lt;ebiggers@google.com&gt;
Cc: Eric Biggers &lt;ebiggers@kernel.org&gt;
Cc: Eric Dumazet &lt;edumazet@google.com&gt;
Cc: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Cc: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
Cc: Ilya Leoshkevich &lt;iii@linux.ibm.com&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: Jens Axboe &lt;axboe@kernel.dk&gt;
Cc: Joonsoo Kim &lt;iamjoonsoo.kim@lge.com&gt;
Cc: Kees Cook &lt;keescook@chromium.org&gt;
Cc: Marco Elver &lt;elver@google.com&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Matthew Wilcox &lt;willy@infradead.org&gt;
Cc: Michael S. Tsirkin &lt;mst@redhat.com&gt;
Cc: Pekka Enberg &lt;penberg@kernel.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Petr Mladek &lt;pmladek@suse.com&gt;
Cc: Stephen Rothwell &lt;sfr@canb.auug.org.au&gt;
Cc: Steven Rostedt &lt;rostedt@goodmis.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Vasily Gorbik &lt;gor@linux.ibm.com&gt;
Cc: Vegard Nossum &lt;vegard.nossum@oracle.com&gt;
Cc: Vlastimil Babka &lt;vbabka@suse.cz&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>kbuild: build init/built-in.a just once</title>
<updated>2022-09-28T19:40:15Z</updated>
<author>
<name>Masahiro Yamada</name>
<email>masahiroy@kernel.org</email>
</author>
<published>2022-08-28T02:39:53Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=2df8220cc511326508ec4da2f43ef69311bdd7b9'/>
<id>urn:sha1:2df8220cc511326508ec4da2f43ef69311bdd7b9</id>
<content type='text'>
Kbuild builds init/built-in.a twice; first during the ordinary
directory descending, second from scripts/link-vmlinux.sh.

We do this because UTS_VERSION contains the build version and the
timestamp. We cannot update it during the normal directory traversal
since we do not yet know if we need to update vmlinux. UTS_VERSION is
temporarily calculated, but omitted from the update check. Otherwise,
vmlinux would be rebuilt every time.

When Kbuild results in running link-vmlinux.sh, it increments the
version number in the .version file and takes the timestamp at that
time to really fix UTS_VERSION.

However, updating the same file twice is a footgun. To avoid nasty
timestamp issues, all build artifacts that depend on init/built-in.a
are atomically generated in link-vmlinux.sh, where some of them do not
need rebuilding.

To fix this issue, this commit changes as follows:

[1] Split UTS_VERSION out to include/generated/utsversion.h from
    include/generated/compile.h

    include/generated/utsversion.h is generated just before the
    vmlinux link. It is generated under include/generated/ because
    some decompressors (s390, x86) use UTS_VERSION.

[2] Split init_uts_ns and linux_banner out to init/version-timestamp.c
    from init/version.c

    init_uts_ns and linux_banner contain UTS_VERSION. During the ordinary
    directory descending, they are compiled with __weak and used to
    determine if vmlinux needs relinking. Just before the vmlinux link,
    they are compiled without __weak to embed the real version and
    timestamp.

Signed-off-by: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
</content>
</entry>
<entry>
<title>x86/boot: Don't propagate uninitialized boot_params-&gt;cc_blob_address</title>
<updated>2022-08-24T07:03:04Z</updated>
<author>
<name>Michael Roth</name>
<email>michael.roth@amd.com</email>
</author>
<published>2022-08-23T16:07:34Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=4b1c742407571eff58b6de9881889f7ca7c4b4dc'/>
<id>urn:sha1:4b1c742407571eff58b6de9881889f7ca7c4b4dc</id>
<content type='text'>
In some cases, bootloaders will leave boot_params-&gt;cc_blob_address
uninitialized rather than zeroing it out. This field is only meant to be
set by the boot/compressed kernel in order to pass information to the
uncompressed kernel when SEV-SNP support is enabled.

Therefore, there are no cases where the bootloader-provided values
should be treated as anything other than garbage. Otherwise, the
uncompressed kernel may attempt to access this bogus address, leading to
a crash during early boot.

Normally, sanitize_boot_params() would be used to clear out such fields
but that happens too late: sev_enable() may have already initialized
it to a valid value that should not be zeroed out. Instead, have
sev_enable() zero it out unconditionally beforehand.

Also ensure this happens for !CONFIG_AMD_MEM_ENCRYPT as well by also
including this handling in the sev_enable() stub function.

  [ bp: Massage commit message and comments. ]

Fixes: b190a043c49a ("x86/sev: Add SEV-SNP feature detection/setup")
Reported-by: Jeremi Piotrowski &lt;jpiotrowski@linux.microsoft.com&gt;
Reported-by: watnuss@gmx.de
Signed-off-by: Michael Roth &lt;michael.roth@amd.com&gt;
Signed-off-by: Borislav Petkov &lt;bp@suse.de&gt;
Cc: stable@vger.kernel.org
Link: https://bugzilla.kernel.org/show_bug.cgi?id=216387
Link: https://lore.kernel.org/r/20220823160734.89036-1-michael.roth@amd.com
</content>
</entry>
<entry>
<title>x86/boot: Remove superfluous type casting from arch/x86/boot/bitops.h</title>
<updated>2022-08-15T17:17:43Z</updated>
<author>
<name>Li kunyu</name>
<email>kunyu@nfschina.com</email>
</author>
<published>2022-07-25T04:23:58Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=039f0e054a29d06970892240d70143150d2aaec2'/>
<id>urn:sha1:039f0e054a29d06970892240d70143150d2aaec2</id>
<content type='text'>
'const void *' will auto-type-convert to just about any other const
pointer type, no need to force it.

  [ mingo: Rewrote the changelog. ]

Signed-off-by: Li kunyu &lt;kunyu@nfschina.com&gt;
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Signed-off-by: Borislav Petkov &lt;bp@suse.de&gt;
Link: https://lore.kernel.org/r/20220725042358.3377-1-kunyu@nfschina.com
</content>
</entry>
<entry>
<title>x86: link vdso and boot with -z noexecstack --no-warn-rwx-segments</title>
<updated>2022-08-11T01:30:09Z</updated>
<author>
<name>Nick Desaulniers</name>
<email>ndesaulniers@google.com</email>
</author>
<published>2022-08-10T22:24:41Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=ffcf9c5700e49c0aee42dcba9a12ba21338e8136'/>
<id>urn:sha1:ffcf9c5700e49c0aee42dcba9a12ba21338e8136</id>
<content type='text'>
Users of GNU ld (BFD) from binutils 2.39+ will observe multiple
instances of a new warning when linking kernels in the form:

  ld: warning: arch/x86/boot/pmjump.o: missing .note.GNU-stack section implies executable stack
  ld: NOTE: This behaviour is deprecated and will be removed in a future version of the linker
  ld: warning: arch/x86/boot/compressed/vmlinux has a LOAD segment with RWX permissions

Generally, we would like to avoid the stack being executable.  Because
there could be a need for the stack to be executable, assembler sources
have to opt-in to this security feature via explicit creation of the
.note.GNU-stack feature (which compilers create by default) or command
line flag --noexecstack.  Or we can simply tell the linker the
production of such sections is irrelevant and to link the stack as
--noexecstack.

LLVM's LLD linker defaults to -z noexecstack, so this flag isn't
strictly necessary when linking with LLD, only BFD, but it doesn't hurt
to be explicit here for all linkers IMO.  --no-warn-rwx-segments is
currently BFD specific and only available in the current latest release,
so it's wrapped in an ld-option check.

While the kernel makes extensive usage of ELF sections, it doesn't use
permissions from ELF segments.

Link: https://lore.kernel.org/linux-block/3af4127a-f453-4cf7-f133-a181cce06f73@kernel.dk/
Link: https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=ba951afb99912da01a6e8434126b8fac7aa75107
Link: https://github.com/llvm/llvm-project/issues/57009
Reported-and-tested-by: Jens Axboe &lt;axboe@kernel.dk&gt;
Suggested-by: Fangrui Song &lt;maskray@google.com&gt;
Signed-off-by: Nick Desaulniers &lt;ndesaulniers@google.com&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>x86/compressed/64: Add identity mappings for setup_data entries</title>
<updated>2022-07-06T09:23:39Z</updated>
<author>
<name>Michael Roth</name>
<email>michael.roth@amd.com</email>
</author>
<published>2022-07-06T02:53:15Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=b57feed2cc2622ae14b2fa62f19e973e5e0a60cf'/>
<id>urn:sha1:b57feed2cc2622ae14b2fa62f19e973e5e0a60cf</id>
<content type='text'>
The decompressed kernel initially relies on the identity map set up by
the boot/compressed kernel for accessing things like boot_params. With
the recent introduction of SEV-SNP support, the decompressed kernel
also needs to access the setup_data entries pointed to by
boot_params-&gt;hdr.setup_data.

This can lead to a crash in the kexec kernel during early boot due to
these entries not currently being included in the initial identity map,
see thread at Link below.

Include mappings for the setup_data entries in the initial identity map.

  [ bp: Massage commit message and use a helper var for better readability. ]

Fixes: b190a043c49a ("x86/sev: Add SEV-SNP feature detection/setup")
Reported-by: Jun'ichi Nomura &lt;junichi.nomura@nec.com&gt;
Signed-off-by: Michael Roth &lt;michael.roth@amd.com&gt;
Signed-off-by: Borislav Petkov &lt;bp@suse.de&gt;
Link: https://lore.kernel.org/r/TYCPR01MB694815CD815E98945F63C99183B49@TYCPR01MB6948.jpnprd01.prod.outlook.com
</content>
</entry>
<entry>
<title>Merge tag 'efi-next-for-v5.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi</title>
<updated>2022-06-03T20:39:30Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2022-06-03T20:39:30Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=93ce7948e38ffe6f9b4fd403c94c098bd892a5ff'/>
<id>urn:sha1:93ce7948e38ffe6f9b4fd403c94c098bd892a5ff</id>
<content type='text'>
Pull more EFI updates from Ard Biesheuvel:
 "Follow-up tweaks for EFI changes - they mostly address issues
  introduced this merge window, except for Heinrich's patch:

   - fix new DXE service invocations for mixed mode

   - use correct Kconfig symbol when setting PE header flag

   - clean up the drivers/firmware/efi Kconfig dependencies so that
     features that depend on CONFIG_EFI are hidden from the UI when the
     symbol is not enabled.

  Also included is a RISC-V bugfix from Heinrich to avoid read-write
  mappings of read-only firmware regions in the EFI page tables"

* tag 'efi-next-for-v5.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi:
  efi: clean up Kconfig dependencies on CONFIG_EFI
  efi/x86: libstub: Make DXE calls mixed mode safe
  efi: x86: Fix config name for setting the NX-compatibility flag in the PE header
  riscv: read-only pages should not be writable
</content>
</entry>
</feed>
