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Linux kernel
============
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In order to build the documentation, use ``make htmldocs`` or
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https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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Pull Kbuild fixes from Masahiro Yamada:
- Reformat nested if-conditionals in Makefiles with 4 spaces
- Fix CONFIG_DEBUG_INFO_BTF builds for big endian
- Fix modpost for module srcversion
- Fix an escape sequence warning in gen_compile_commands.py
- Fix kallsyms to ignore ARMv4 thunk symbols
* tag 'kbuild-fixes-v6.8-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
kallsyms: ignore ARMv4 thunks along with others
modpost: trim leading spaces when processing source files list
gen_compile_commands: fix invalid escape sequence warning
kbuild: Fix changing ELF file type for output of gen_btf for big endian
docs: kconfig: Fix grammar and formatting
kbuild: use 4-space indentation when followed by conditionals
Pull x86 fix from Borislav Petkov:
- Use a GB page for identity mapping only when memory of this size is
requested so that mapping of reserved regions is prevented which
would otherwise lead to system crashes on UV machines
* tag 'x86_urgent_for_v6.8_rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mm/ident_map: Use gbpages only where full GB page should be mapped.
lld is now able to build ARMv4 and ARMv4T kernels, which means it can
generate thunks for those (__ARMv4PILongThunk_*, __ARMv4PILongBXThunk_*)
that can interfere with kallsyms table generation since they do not get
ignore like the corresponding ARMv5+ ones are:
Inconsistent kallsyms data
Try "make KALLSYMS_EXTRA_PASS=1" as a workaround
Replace the hardcoded list of thunk symbols with a more general regex that
covers this one along with future symbols that follow the same pattern.
Fixes: 5eb6e280432d ("ARM: 9289/1: Allow pre-ARMv5 builds with ld.lld 16.0.0 and newer")
Fixes: efe6e3068067 ("kallsyms: fix nonconverging kallsyms table with lld")
Suggested-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Pull irq fixes from Borislav Petkov:
- Fix GICv4.1 affinity update
- Restore a quirk for ACPI-based GICv4 systems
- Handle non-coherent GICv4 redistributors properly
- Prevent spurious interrupts on Broadcom devices using GIC v3
architecture
- Other minor fixes
* tag 'irq_urgent_for_v6.8_rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
irqchip/gic-v3-its: Fix GICv4.1 VPE affinity update
irqchip/gic-v3-its: Restore quirk probing for ACPI-based systems
irqchip/gic-v3-its: Handle non-coherent GICv4 redistributors
irqchip/qcom-mpm: Fix IS_ERR() vs NULL check in qcom_mpm_init()
irqchip/loongson-eiointc: Use correct struct type in eiointc_domain_alloc()
irqchip/irq-brcmstb-l2: Add write memory barrier before exit
When ident_pud_init() uses only gbpages to create identity maps, large
ranges of addresses not actually requested can be included in the
resulting table; a 4K request will map a full GB. On UV systems, this
ends up including regions that will cause hardware to halt the system
if accessed (these are marked "reserved" by BIOS). Even processor
speculation into these regions is enough to trigger the system halt.
Only use gbpages when map creation requests include the full GB page
of space. Fall back to using smaller 2M pages when only portions of a
GB page are included in the request.
No attempt is made to coalesce mapping requests. If a request requires
a map entry at the 2M (pmd) level, subsequent mapping requests within
the same 1G region will also be at the pmd level, even if adjacent or
overlapping such requests could have been combined to map a full
gbpage. Existing usage starts with larger regions and then adds
smaller regions, so this should not have any great consequence.
[ dhansen: fix up comment formatting, simplifty changelog ]
Signed-off-by: Steve Wahl <steve.wahl@hpe.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/all/20240126164841.170866-1-steve.wahl%40hpe.com
get_line() does not trim the leading spaces, but the
parse_source_files() expects to get lines with source files paths where
the first space occurs after the file path.
Fixes: 70f30cfe5b89 ("modpost: use read_text_file() and get_line() for reading text files")
Signed-off-by: Radek Krejci <radek.krejci@oracle.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Pull i2c fixes from Wolfram Sang:
"Two fixes for i801 and qcom-geni devices. Meanwhile, a fix from Arnd
addresses a compilation error encountered during compile test on
powerpc"
* tag 'i2c-for-6.8-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
i2c: i801: Fix block process call transactions
i2c: pasemi: split driver into two separate modules
i2c: qcom-geni: Correct I2C TRE sequence
When updating the affinity of a VPE, the VMOVP command is currently skipped
if the two CPUs are part of the same VPE affinity.
But this is wrong, as the doorbell corresponding to this VPE is still
delivered on the 'old' CPU, which screws up the balancing. Furthermore,
offlining that 'old' CPU results in doorbell interrupts generated for this
VPE being discarded.
The harsh reality is that VMOVP cannot be elided when a set_affinity()
request occurs. It needs to be obeyed, and if an optimisation is to be
made, it is at the point where the affinity change request is made (such as
in KVM).
Drop the VMOVP elision altogether, and only use the vpe_table_mask
to try and stay within the same ITS affinity group if at all possible.
Fixes: dd3f050a216e (irqchip/gic-v4.1: Implement the v4.1 flavour of VMOVP)
Reported-by: Kunkun Jiang <jiangkunkun@huawei.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20240213101206.2137483-4-maz@kernel.org
The kernel built with MCRUSOE is unbootable on Transmeta Crusoe. It shows
the following error message:
This kernel requires an i686 CPU, but only detected an i586 CPU.
Unable to boot - please use a kernel appropriate for your CPU.
Remove MCRUSOE from the condition introduced in commit in Fixes, effectively
changing X86_MINIMUM_CPU_FAMILY back to 5 on that machine, which matches the
CPU family given by CPUID.
[ bp: Massage commit message. ]
Fixes: 25d76ac88821 ("x86/Kconfig: Explicitly enumerate i686-class CPUs in Kconfig")
Signed-off-by: Aleksander Mazur <deweloper@wp.pl>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Cc: <stable@kernel.org>
Link: https://lore.kernel.org/r/20240123134309.1117782-1-deweloper@wp.pl
With python 3.12, '\#' results in this warning
SyntaxWarning: invalid escape sequence '\#'
Signed-off-by: Andrew Ballance <andrewjballance@gmail.com>
Reviewed-by: Justin Stitt <justinstitt@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Pull powerpc fixes from Michael Ellerman:
"This is a bit of a big batch for rc4, but just due to holiday hangover
and because I didn't send any fixes last week due to a late revert
request. I think next week should be back to normal.
- Fix ftrace bug on boot caused by exit text sections with
'-fpatchable-function-entry'
- Fix accuracy of stolen time on pseries since the switch to
VIRT_CPU_ACCOUNTING_GEN
- Fix a crash in the IOMMU code when doing DLPAR remove
- Set pt_regs->link on scv entry to fix BPF stack unwinding
- Add missing PPC_FEATURE_BOOKE on 64-bit e5500/e6500, which broke
gdb
- Fix boot on some 6xx platforms with STRICT_KERNEL_RWX enabled
- Fix build failures with KASAN enabled and 32KB stack size
- Some other minor fixes
Thanks to Arnd Bergmann, Benjamin Gray, Christophe Leroy, David
Engraf, Gaurav Batra, Jason Gunthorpe, Jiangfeng Xiao, Matthias
Schiffer, Nathan Lynch, Naveen N Rao, Nicholas Piggin, Nysal Jan K.A,
R Nageswara Sastry, Shivaprasad G Bhat, Shrikanth Hegde, Spoorthy,
Srikar Dronamraju, and Venkat Rao Bagalkote"
* tag 'powerpc-6.8-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/iommu: Fix the missing iommu_group_put() during platform domain attach
powerpc/pseries: fix accuracy of stolen time
powerpc/ftrace: Ignore ftrace locations in exit text sections
powerpc/cputable: Add missing PPC_FEATURE_BOOKE on PPC64 Book-E
powerpc/kasan: Limit KASAN thread size increase to 32KB
Revert "powerpc/pseries/iommu: Fix iommu initialisation during DLPAR add"
powerpc: 85xx: mark local functions static
powerpc: udbg_memcons: mark functions static
powerpc/kasan: Fix addr error caused by page alignment
powerpc/6xx: set High BAT Enable flag on G2_LE cores
selftests/powerpc/papr_vpd: Check devfd before get_system_loc_code()
powerpc/64: Set task pt_regs->link to the LR value on scv entry
powerpc/pseries/iommu: Fix iommu initialisation during DLPAR add
powerpc/pseries/papr-sysparm: use u8 arrays for payloads
Three fixes are included here. Two are strictly hardware-related
for the i801 and qcom-geni devices. Meanwhile, a fix from Arnd
addresses a compilation error encountered during compile test on
powerpc.
While refactoring the way the ITSs are probed, the handling of quirks
applicable to ACPI-based platforms was lost. As a result, systems such as
HIP07 lose their GICv4 functionnality, and some other may even fail to
boot, unless they are configured to boot with DT.
Move the enabling of quirks into its_probe_one(), making it common to all
firmware implementations.
Fixes: 9585a495ac93 ("irqchip/gic-v3-its: Split allocation from initialisation of its_node")
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Reviewed-by: Zenghui Yu <yuzenghui@huawei.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20240213101206.2137483-3-maz@kernel.org
Before this change, the expected size of the user space buffer was
taken from fx_sw->xstate_size. fx_sw->xstate_size can be changed
from user-space, so it is possible construct a sigreturn frame where:
* fx_sw->xstate_size is smaller than the size required by valid bits in
fx_sw->xfeatures.
* user-space unmaps parts of the sigrame fpu buffer so that not all of
the buffer required by xrstor is accessible.
In this case, xrstor tries to restore and accesses the unmapped area
which results in a fault. But fault_in_readable succeeds because buf +
fx_sw->xstate_size is within the still mapped area, so it goes back and
tries xrstor again. It will spin in this loop forever.
Instead, fault in the maximum size which can be touched by XRSTOR (taken
from fpstate->user_size).
[ dhansen: tweak subject / changelog ]
Fixes: fcb3635f5018 ("x86/fpu/signal: Handle #PF in the direct restore path")
Reported-by: Konstantin Bogomolov <bogomolov@google.com>
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrei Vagin <avagin@google.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc:stable@vger.kernel.org
Link: https://lore.kernel.org/all/20240130063603.3392627-1-avagin%40google.com
Commit 90ceddcb4950 ("bpf: Support llvm-objcopy for vmlinux BTF")
changed the ELF type of .btf.vmlinux.bin.o to ET_REL via dd, which works
fine for little endian platforms:
00000000 7f 45 4c 46 02 01 01 00 00 00 00 00 00 00 00 00 |.ELF............|
-00000010 03 00 b7 00 01 00 00 00 00 00 00 80 00 80 ff ff |................|
+00000010 01 00 b7 00 01 00 00 00 00 00 00 80 00 80 ff ff |................|
However, for big endian platforms, it changes the wrong byte, resulting
in an invalid ELF file type, which ld.lld rejects:
00000000 7f 45 4c 46 02 02 01 00 00 00 00 00 00 00 00 00 |.ELF............|
-00000010 00 03 00 16 00 00 00 01 00 00 00 00 00 10 00 00 |................|
+00000010 01 03 00 16 00 00 00 01 00 00 00 00 00 10 00 00 |................|
Type: <unknown>: 103
ld.lld: error: .btf.vmlinux.bin.o: unknown file type
Fix this by updating the entire 16-bit e_type field rather than just a
single byte, so that everything works correctly for all platforms and
linkers.
00000000 7f 45 4c 46 02 02 01 00 00 00 00 00 00 00 00 00 |.ELF............|
-00000010 00 03 00 16 00 00 00 01 00 00 00 00 00 10 00 00 |................|
+00000010 00 01 00 16 00 00 00 01 00 00 00 00 00 10 00 00 |................|
Type: REL (Relocatable file)
While in the area, update the comment to mention that binutils 2.35+
matches LLD's behavior of rejecting an ET_EXEC input, which occurred
after the comment was added.
Cc: stable@vger.kernel.org
Fixes: 90ceddcb4950 ("bpf: Support llvm-objcopy for vmlinux BTF")
Link: https://github.com/llvm/llvm-project/pull/75643
Suggested-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Fangrui Song <maskray@google.com>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Justin Stitt <justinstitt@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
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