tjh.dev
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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git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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Pull x86 fixes from Ingo Molnar:
"Two fixes: a quirk for KVM guests running on certain AMD CPUs, and a
KASAN related build fix"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/CPU/AMD: Don't force the CPB cap when running under a hypervisor
x86/boot: Provide KASAN compatible aliases for string routines
Pull perf fixes from Ingo Molnar:
"On the kernel side there's a bunch of ring-buffer ordering fixes for a
reproducible bug, plus a PEBS constraints regression fix.
Plus tooling fixes"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
tools headers UAPI: Sync kvm.h headers with the kernel sources
perf record: Fix s390 missing module symbol and warning for non-root users
perf machine: Read also the end of the kernel
perf test vmlinux-kallsyms: Ignore aliases to _etext when searching on kallsyms
perf session: Add missing swap ops for namespace events
perf namespace: Protect reading thread's namespace
tools headers UAPI: Sync drm/drm.h with the kernel
tools headers UAPI: Sync drm/i915_drm.h with the kernel
tools headers UAPI: Sync linux/fs.h with the kernel
tools headers UAPI: Sync linux/sched.h with the kernel
tools arch x86: Sync asm/cpufeatures.h with the with the kernel
tools include UAPI: Update copy of files related to new fspick, fsmount, fsconfig, fsopen, move_mount and open_tree syscalls
perf arm64: Fix mksyscalltbl when system kernel headers are ahead of the kernel
perf data: Fix 'strncat may truncate' build failure with recent gcc
perf/ring-buffer: Use regular variables for nesting
perf/ring-buffer: Always use {READ,WRITE}_ONCE() for rb->user_page data
perf/ring_buffer: Add ordering to rb->nest increment
perf/ring_buffer: Fix exposing a temporarily decreased data_head
perf/x86/intel/ds: Fix EVENT vs. UEVENT PEBS constraints
For F17h AMD CPUs, the CPB capability ('Core Performance Boost') is forcibly set,
because some versions of that chip incorrectly report that they do not have it.
However, a hypervisor may filter out the CPB capability, for good
reasons. For example, KVM currently does not emulate setting the CPB
bit in MSR_K7_HWCR, and unchecked MSR access errors will be thrown
when trying to set it as a guest:
unchecked MSR access error: WRMSR to 0xc0010015 (tried to write 0x0000000001000011) at rIP: 0xffffffff890638f4 (native_write_msr+0x4/0x20)
Call Trace:
boost_set_msr+0x50/0x80 [acpi_cpufreq]
cpuhp_invoke_callback+0x86/0x560
sort_range+0x20/0x20
cpuhp_thread_fun+0xb0/0x110
smpboot_thread_fn+0xef/0x160
kthread+0x113/0x130
kthread_create_worker_on_cpu+0x70/0x70
ret_from_fork+0x35/0x40
To avoid this issue, don't forcibly set the CPB capability for a CPU
when running under a hypervisor.
Signed-off-by: Frank van der Linden <fllinden@amazon.com>
Acked-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bp@alien8.de
Cc: jiaxun.yang@flygoat.com
Fixes: 0237199186e7 ("x86/CPU/AMD: Set the CPB bit unconditionally on F17h")
Link: http://lkml.kernel.org/r/20190522221745.GA15789@dev-dsk-fllinden-2c-c1893d73.us-west-2.amazon.com
[ Minor edits to the changelog. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull EFI fixes from Ingo Molnar:
"Two EFI fixes: a quirk for weird systabs, plus add more robust error
handling in the old 1:1 mapping code"
* 'efi-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
efi: Allow the number of EFI configuration tables entries to be zero
efi/x86/Add missing error handling to old_memmap 1:1 mapping code
Pull perf/urgent fixes:
BPF:
Jiri Olsa:
- Fixup determination of end of kernel map, to avoid having BPF programs,
that are after the kernel headers and just before module texts mixed up in
the kernel map.
tools UAPI header copies:
Arnaldo Carvalho de Melo:
- Update copy of files related to new fspick, fsmount, fsconfig, fsopen,
move_mount and open_tree syscalls.
- Sync cpufeatures.h, sched.h, fs.h, drm.h, i915_drm.h and kvm.h headers.
Namespaces:
Namhyung Kim:
- Add missing byte swap ops for namespace events when processing records from
perf.data files that could have been recorded in a arch with a different
endianness.
- Fix access to the thread namespaces list by using the namespaces_lock.
perf data:
Shawn Landden:
- Fix 'strncat may truncate' build failure with recent gcc.
s/390
Thomas Richter:
- Fix s390 missing module symbol and warning for non-root users in 'perf record'.
arm64:
Vitaly Chikunov:
- Fix mksyscalltbl when system kernel headers are ahead of the kernel.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The KASAN subsystem wraps calls to memcpy(), memset() and memmove()
to sanitize the arguments before invoking the actual routines, which
have been renamed to __memcpy(), __memset() and __memmove(),
respectively. When CONFIG_KASAN is enabled for the kernel build but
KASAN code generation is disabled for the compilation unit (which is
needed for things like the EFI stub or the decompressor), the string
routines are just #define'd to their __ prefixed names so that they
are simply invoked directly.
This does however rely on those __ prefixed names to exist in the
symbol namespace, which is not currently the case for the x86
decompressor, which may lead to errors like
drivers/firmware/efi/libstub/tpm.o: In function `efi_retrieve_tpm2_eventlog':
tpm.c:(.text+0x2a8): undefined reference to `__memcpy'
So let's expose the __ prefixed symbols in the decompressor when
KASAN is enabled.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthew Garrett <matthewgarrett@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull stacktrace fix from Ingo Molnar:
"Fix a stack_trace_save_tsk_reliable() regression"
* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
stacktrace: Unbreak stack_trace_save_tsk_reliable()
Only try and access the EFI configuration tables if there there are any
reported. This allows EFI to be continued to used on systems where there
are no configuration table entries.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Gen Zhang <blackgod016574@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20190525112559.7917-3-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
While the IRQ/NMI will nest, the nest-count will be invariant over the
actual exception, since it will decrement equal to increment.
This means we can -- carefully -- use a regular variable since the
typical LOAD-STORE race doesn't exist (similar to preempt_count).
This optimizes the ring-buffer for all LOAD-STORE architectures, since
they need to use atomic ops to implement local_t.
Suggested-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: acme@kernel.org
Cc: mark.rutland@arm.com
Cc: namhyung@kernel.org
Cc: yabinc@google.com
Link: http://lkml.kernel.org/r/20190517115418.481392777@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
dd53f6102c30 ("Merge tag 'kvmarm-for-v5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD")
59c5c58c5b93 ("Merge tag 'kvm-ppc-next-5.2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc into HEAD")
d7547c55cbe7 ("KVM: Introduce KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2")
6520ca64cde7 ("KVM: PPC: Book3S HV: XIVE: Add a mapping for the source ESB pages")
39e9af3de5ca ("KVM: PPC: Book3S HV: XIVE: Add a TIMA mapping")
e4945b9da52b ("KVM: PPC: Book3S HV: XIVE: Add get/set accessors for the VP XIVE state")
e6714bd1671d ("KVM: PPC: Book3S HV: XIVE: Add a control to dirty the XIVE EQ pages")
7b46b6169ab8 ("KVM: PPC: Book3S HV: XIVE: Add a control to sync the sources")
5ca806474859 ("KVM: PPC: Book3S HV: XIVE: Add a global reset control")
13ce3297c576 ("KVM: PPC: Book3S HV: XIVE: Add controls for the EQ configuration")
e8676ce50e22 ("KVM: PPC: Book3S HV: XIVE: Add a control to configure a source")
4131f83c3d64 ("KVM: PPC: Book3S HV: XIVE: add a control to initialize a source")
eacc56bb9de3 ("KVM: PPC: Book3S HV: XIVE: Introduce a new capability KVM_CAP_PPC_IRQ_XIVE")
90c73795afa2 ("KVM: PPC: Book3S HV: Add a new KVM device for the XIVE native exploitation mode")
4f45b90e1c03 ("KVM: s390: add deflate conversion facilty to cpu model")
a243c16d18be ("KVM: arm64: Add capability to advertise ptrauth for guest")
a22fa321d13b ("KVM: arm64: Add userspace flag to enable pointer authentication")
4bd774e57b29 ("KVM: arm64/sve: Simplify KVM_REG_ARM64_SVE_VLS array sizing")
8ae6efdde451 ("KVM: arm64/sve: Clean up UAPI register ID definitions")
173aec2d5a9f ("KVM: s390: add enhanced sort facilty to cpu model")
555f3d03e7fb ("KVM: arm64: Add a capability to advertise SVE support")
9033bba4b535 ("KVM: arm64/sve: Add pseudo-register for the guest's vector lengths")
7dd32a0d0103 ("KVM: arm/arm64: Add KVM_ARM_VCPU_FINALIZE ioctl")
e1c9c98345b3 ("KVM: arm64/sve: Add SVE support to register access ioctl interface")
2b953ea34812 ("KVM: Allow 2048-bit register access via ioctl interface")
None entails changes in tooling, the closest to that were some new arch
specific ioctls, that are still not handled by the tools/perf/trace/beauty/
library, that needs to create per-arch tables to convert ioctl cmd->string (and
back).
From a quick look the arch specific kvm-stat.c files at:
$ ls -1 tools/perf/arch/*/util/kvm-stat.c
tools/perf/arch/powerpc/util/kvm-stat.c
tools/perf/arch/s390/util/kvm-stat.c
tools/perf/arch/x86/util/kvm-stat.c
$
Are not affected.
This silences these perf building warnings:
Warning: Kernel ABI header at 'tools/include/uapi/linux/kvm.h' differs from latest version at 'include/uapi/linux/kvm.h'
diff -u tools/include/uapi/linux/kvm.h include/uapi/linux/kvm.h
Warning: Kernel ABI header at 'tools/arch/powerpc/include/uapi/asm/kvm.h' differs from latest version at 'arch/powerpc/include/uapi/asm/kvm.h'
diff -u tools/arch/powerpc/include/uapi/asm/kvm.h arch/powerpc/include/uapi/asm/kvm.h
Warning: Kernel ABI header at 'tools/arch/s390/include/uapi/asm/kvm.h' differs from latest version at 'arch/s390/include/uapi/asm/kvm.h'
diff -u tools/arch/s390/include/uapi/asm/kvm.h arch/s390/include/uapi/asm/kvm.h
Warning: Kernel ABI header at 'tools/arch/arm64/include/uapi/asm/kvm.h' differs from latest version at 'arch/arm64/include/uapi/asm/kvm.h'
diff -u tools/arch/arm64/include/uapi/asm/kvm.h arch/arm64/include/uapi/asm/kvm.h
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Amit Daniel Kachhap <amit.kachhap@arm.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Cédric Le Goater <clg@kaod.org>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Dave Martin <Dave.Martin@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Luis Cláudio Gonçalves <lclaudio@redhat.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Paul Mackerras <paulus@ozlabs.org>
Cc: Peter Xu <peterx@redhat.com>
Link: https://lkml.kernel.org/n/tip-3msmqjenlmb7eygcdnmlqaq1@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Pull arm64 fixes from Will Deacon:
- Fix SPE probe failure when backing auxbuf with high-order pages
- Fix handling of DMA allocations from outside of the vmalloc area
- Fix generation of build-id ELF section for vDSO object
- Disable huge I/O mappings if kernel page table dumping is enabled
- A few other minor fixes (comments, kconfig etc)
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64: vdso: Explicitly add build-id option
arm64/mm: Inhibit huge-vmap with ptdump
arm64: Print physical address of page table base in show_pte()
arm64: don't trash config with compat symbol if COMPAT is disabled
arm64: assembler: Update comment above cond_yield_neon() macro
drivers/perf: arm_spe: Don't error on high-order pages for aux buf
arm64/iommu: handle non-remapped addresses in ->mmap and ->get_sgtable
Pull SPDX fixes from Greg KH:
"Here are just two small patches, that fix up some found SPDX
identifier issues.
The first patch fixes an error in a previous SPDX fixup patch, that
causes build errors when doing 'make clean' on the tree (the fact that
almost no one noticed it reflects the fact that kernel developers
don't like doing that option very often...)
The second patch fixes up a number of places in the tree where people
mistyped the string "SPDX-License-Identifier". Given that people can
not even type their own name all the time without mistakes, this was
bound to happen, and odds are, we will have to add some type of check
for this to checkpatch.pl to catch this happening in the future.
Both of these have passed testing by 0-day"
* tag 'spdx-5.2-rc3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
treewide: fix typos of SPDX-License-Identifier
crypto: ux500 - fix license comment syntax error
Miroslav reported that the livepatch self-tests were failing, specifically
a case in which the consistency model ensures that a current executing
function is not allowed to be patched, "TEST: busy target module".
Recent renovations of stack_trace_save_tsk_reliable() left it returning
only an -ERRNO success indication in some configuration combinations:
klp_check_stack()
ret = stack_trace_save_tsk_reliable()
#ifdef CONFIG_ARCH_STACKWALK && CONFIG_HAVE_RELIABLE_STACKTRACE
stack_trace_save_tsk_reliable()
ret = arch_stack_walk_reliable()
return 0
return -EINVAL
...
return ret;
...
if (ret < 0)
/* stack_trace_save_tsk_reliable error */
nr_entries = ret; << 0
Previously (and currently for !CONFIG_ARCH_STACKWALK &&
CONFIG_HAVE_RELIABLE_STACKTRACE) stack_trace_save_tsk_reliable() returned
the number of entries that it consumed in the passed storage array.
In the case of the above config and trace, be sure to return the
stacktrace_cookie.len on stack_trace_save_tsk_reliable() success.
Fixes: 25e39e32b0a3f ("livepatch: Simplify stack trace retrieval")
Reported-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Joe Lawrence <joe.lawrence@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: live-patching@vger.kernel.org
Cc: jikos@kernel.org
Cc: pmladek@suse.com
Link: https://lkml.kernel.org/r/20190517185117.24642-1-joe.lawrence@redhat.com
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