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Linux kernel
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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.
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On 32-bit kernels, 64-bit syscall arguments are split into two
registers. For that to work with syscall wrappers, the prototype of the
syscall must have the argument split so that the wrapper macro properly
unpacks the arguments from pt_regs.
The fanotify_mark() syscall is one such syscall, which already has a
split prototype, guarded behind ARCH_SPLIT_ARG64.
So select ARCH_SPLIT_ARG64 to get that prototype and fix fanotify_mark()
on 32-bit kernels with syscall wrappers.
Note also that fanotify_mark() is the only usage of ARCH_SPLIT_ARG64.
Fixes: 7e92e01b7245 ("powerpc: Provide syscall wrapper")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20221101034852.2340319-1-mpe@ellerman.id.au
With the introduction of syscall wrappers all wrappers for syscalls with
64-bit arguments must be handled specially, not only those that have
unaligned 64-bit arguments. This left out the fallocate() and
sync_file_range2() syscalls.
Fixes: 7e92e01b7245 ("powerpc: Provide syscall wrapper")
Fixes: e23750623835 ("powerpc/32: fix syscall wrappers with 64-bit arguments of unaligned register-pairs")
Signed-off-by: Andreas Schwab <schwab@linux-m68k.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/87mt9cxd6g.fsf_-_@igel.home
The macros are defined backwards.
This affects the following compat syscalls:
- compat_sys_truncate64()
- compat_sys_ftruncate64()
- compat_sys_fallocate()
- compat_sys_sync_file_range()
- compat_sys_fadvise64_64()
- compat_sys_readahead()
- compat_sys_pread64()
- compat_sys_pwrite64()
Fixes: 43d5de2b67d7 ("asm-generic: compat: Support BE for long long args in 32-bit ABIs")
Signed-off-by: Andreas Schwab <schwab@linux-m68k.org>
[mpe: Add list of affected syscalls]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/871qqoyvni.fsf_-_@igel.home
There's a build failure for Book3E without AltiVec:
Error: cc1: error: AltiVec not supported in this target
make[6]: *** [/linux/scripts/Makefile.build:250:
drivers/gpu/drm/amd/amdgpu/../display/dc/dml/display_mode_lib.o] Error 1
This happens because the amdgpu build is only gated by
PPC_LONG_DOUBLE_128, but that symbol can be enabled even though AltiVec
is disabled.
The only user of PPC_LONG_DOUBLE_128 is amdgpu, so just add a dependency
on AltiVec to that symbol to fix the build.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20221027125626.1383092-1-mpe@ellerman.id.au
Merge rc2 into our fixes branch, which was based on rc1 but wasn't
merged until rc3, so that for the remainder of the release our fixes
branch will be based on rc2 for the purposes of resolving conflicts with
other trees (if necessary).
Commit a4cb3651a1743 ("powerpc/64s/interrupt: Fix lost interrupts when
returning to soft-masked context") fixed the problem of pending irqs
being cleared when clearing the HARD_DIS bit, but then it didn't clear
the bit at all. This change clears HARD_DIS without affecting other bits
in the mask.
When an interrupt hits in a soft-masked section that has MSR[EE]=1, it
can hard disable and set PACA_IRQS_HARD_DIS, which must be cleared when
returning to the EE=1 caller (unless it was set due to a MUST_HARD_MASK
interrupt becoming pending). Failure to clear this leaves the
returned-to context running with MSR[EE]=1 and PACA_IRQS_HARD_DIS, which
confuses irq assertions and could be dangerous for code that might test
the flag.
This was observed in a hash MMU kernel where a kernel hash fault hits in
a local_irqs_disabled region that has EE=1. The hash fault also runs
with EE=1, then as it returns, a decrementer hits in the restart section
and the irq restart code hard-masks which sets the PACA_IRQ_HARD_DIS
flag, which is not clear when the original context is returned to.
Reported-by: Sachin Sant <sachinp@linux.ibm.com>
Fixes: a4cb3651a1743 ("powerpc/64s/interrupt: Fix lost interrupts when returning to soft-masked context")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Tested-by: Sachin Sant <sachinp@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20221022052207.471328-1-npiggin@gmail.com
NMI interrupts should exit with EXCEPTION_RESTORE_REGS not with
interrupt_return_srr, which is what the perf NMI handler currently does.
This breaks if a PMI hits after interrupt_exit_user_prepare_main() has
switched the context tracking to user mode, then the CT_WARN_ON() in
interrupt_exit_kernel_prepare() fires because it returns to kernel with
context set to user.
This could possibly be solved by soft-disabling PMIs in the exit path,
but that reduces our ability to profile that code. The warning could be
removed, but it's potentially useful.
All other NMIs and soft-NMIs return using EXCEPTION_RESTORE_REGS, so
this makes perf interrupts consistent with that and seems like the best
fix.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Squash in fixups from Nick]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20221006140413.126443-3-npiggin@gmail.com
Pull kvm fixes from Paolo Bonzini:
"RISC-V:
- Fix compilation without RISCV_ISA_ZICBOM
- Fix kvm_riscv_vcpu_timer_pending() for Sstc
ARM:
- Fix a bug preventing restoring an ITS containing mappings for very
large and very sparse device topology
- Work around a relocation handling error when compiling the nVHE
object with profile optimisation
- Fix for stage-2 invalidation holding the VM MMU lock for too long
by limiting the walk to the largest block mapping size
- Enable stack protection and branch profiling for VHE
- Two selftest fixes
x86:
- add compat implementation for KVM_X86_SET_MSR_FILTER ioctl
selftests:
- synchronize includes between include/uapi and tools/include/uapi"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
tools: include: sync include/api/linux/kvm.h
KVM: x86: Add compat handler for KVM_X86_SET_MSR_FILTER
KVM: x86: Copy filter arg outside kvm_vm_ioctl_set_msr_filter()
kvm: Add support for arch compat vm ioctls
RISC-V: KVM: Fix kvm_riscv_vcpu_timer_pending() for Sstc
RISC-V: Fix compilation without RISCV_ISA_ZICBOM
KVM: arm64: vgic: Fix exit condition in scan_its_table()
KVM: arm64: nvhe: Fix build with profile optimization
KVM: selftests: Fix number of pages for memory slot in memslot_modification_stress_test
KVM: arm64: selftests: Fix multiple versions of GIC creation
KVM: arm64: Enable stack protection and branch profiling for VHE
KVM: arm64: Limit stage2_apply_range() batch size to largest block
KVM: arm64: Work out supported block level at compile time
NMI PMIs really should not return using the normal interrupt_return
function. If such a PMI hits in code returning to user with the context
switched to user mode, this warning can fire. This was enough to cause
crashes when reproducing on 64s, because another perf interrupt would
hit while reporting bug, and that would cause another bug, and so on
until smashing the stack.
Work around that particular crash for now by just disabling that context
warning for PMIs. This is a hack and not a complete fix, there could be
other such problems lurking in corners. But it does fix the known crash.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20221014030729.2077151-3-npiggin@gmail.com
This reverts commit 72a95859728a7866522e6633818bebc1c2519b17.
It broke reboots on big-endian MIPS and MIPS64 malta QEMU instances,
which use the syscon driver. Little-endian is not effected, which means
likely it's important to handle regmap_get_val_endian() in this function
after all.
Fixes: 72a95859728a ("mfd: syscon: Remove repetition of the regmap_get_val_endian()")
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Lee Jones <lee@kernel.org>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Provide a definition of KVM_CAP_DIRTY_LOG_RING_ACQ_REL.
Fixes: 17601bfed909 ("KVM: Add KVM_CAP_DIRTY_LOG_RING_ACQ_REL capability and config option")
Cc: Marc Zyngier <maz@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The context tracking code in PR-KVM and BookE implementations is not
complete, and can cause host crashes if context tracking is enabled.
Make these implementations depend on !CONTEXT_TRACKING_USER.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20221014030729.2077151-2-npiggin@gmail.com
Commit bfca3dd3d068 ("kernel/utsname_sysctl.c: print kernel arch") added
a new entry to the uts_kern_table[] array, but didn't update the
UTS_PROC_xyz enumerators of older entries, breaking anything that used
them.
Which is admittedly not many cases: it's really just the two uses of
uts_proc_notify() in kernel/sys.c. But apparently journald-systemd
actually uses this to detect hostname changes.
Reported-by: Torsten Hilbrich <torsten.hilbrich@secunet.com>
Fixes: bfca3dd3d068 ("kernel/utsname_sysctl.c: print kernel arch")
Link: https://lore.kernel.org/lkml/0c2b92a6-0f25-9538-178f-eee3b06da23f@secunet.com/
Link: https://linux-regtracking.leemhuis.info/regzbot/regression/0c2b92a6-0f25-9538-178f-eee3b06da23f@secunet.com/
Cc: Petr Vorel <pvorel@suse.cz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The KVM_X86_SET_MSR_FILTER ioctls contains a pointer in the passed in
struct which means it has a different struct size depending on whether
it gets called from 32bit or 64bit code.
This patch introduces compat code that converts from the 32bit struct to
its 64bit counterpart which then gets used going forward internally.
With this applied, 32bit QEMU can successfully set MSR bitmaps when
running on 64bit kernels.
Reported-by: Andrew Randrianasulu <randrianasulu@gmail.com>
Fixes: 1a155254ff937 ("KVM: x86: Introduce MSR filtering")
Signed-off-by: Alexander Graf <graf@amazon.com>
Message-Id: <20221017184541.2658-4-graf@amazon.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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