tjh.dev
Linux kernel
============
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There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.
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 perf fixes from Thomas Gleixner:
"A pile of perf updates:
Kernel side:
- Remove an incorrect warning in uprobe_init_insn() when
insn_get_length() fails. The error return code is handled at the
call site.
- Move the inline keyword to the right place in the perf ringbuffer
code to address a W=1 build warning.
Tooling:
perf stat:
- Fix metric column header display alignment
- Improve error messages for default attributes, providing better
output for error in command line.
- Add --interval-clear option, to provide a 'watch' like printing
perf script:
- Show hw-cache events too
perf c2c:
- Fix data dependency problem in layout of 'struct c2c_hist_entry'
Core:
- Do not blindly assume that 'struct perf_evsel' can be obtained via
a straight forward container_of() as there are call sites which
hand in a plain 'struct hist' which is not part of a container.
- Fix error index in the PMU event parser, so that error messages can
point to the problematic token"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/core: Move the inline keyword at the beginning of the function declaration
uprobes/x86: Remove incorrect WARN_ON() in uprobe_init_insn()
perf script: Show hw-cache events
perf c2c: Keep struct hist_entry at the end of struct c2c_hist_entry
perf stat: Add event parsing error handling to add_default_attributes
perf stat: Allow to specify specific metric column len
perf stat: Fix metric column header display alignment
perf stat: Use only color_fprintf call in print_metric_only
perf stat: Add --interval-clear option
perf tools: Fix error index for pmu event parser
perf hists: Reimplement hists__has_callchains()
perf hists browser gtk: Use hist_entry__has_callchains()
perf hists: Make hist_entry__has_callchains() work with 'perf c2c'
perf hists: Save the callchain_size in struct hist_entry
Pull rseq fixes from Thomas Gleixer:
"A pile of rseq related fixups:
- Prevent infinite recursion when delivering SIGSEGV
- Remove the abort of rseq critical section on fork() as syscalls
inside rseq critical sections are explicitely forbidden. So no
point in doing the abort on the child.
- Align the rseq structure on 32 bytes in the ARM selftest code.
- Fix file permissions of the test script"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
rseq: Avoid infinite recursion when delivering SIGSEGV
rseq/cleanup: Do not abort rseq c.s. in child on fork()
rseq/selftests/arm: Align 'struct rseq_cs' on 32 bytes
rseq/selftests: Make run_param_test.sh executable
When building perf with W=1 the following warning triggers:
CC kernel/events/ring_buffer.o
kernel/events/ring_buffer.c:105:1: warning: ‘inline’ is not at beginning of declaration [-Wold-style-declaration]
static bool __always_inline
^~~~~~
...
Move the inline keyword to the beginning of the function declaration.
Signed-off-by: Mathieu Malaterre <malat@debian.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: trival@kernel.org
Link: http://lkml.kernel.org/r/20180308202856.9378-1-malat@debian.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull EFI fixes from Thomas Gleixner:
"Two fixlets for the EFI maze:
- Properly zero variables to prevent an early boot hang on EFI mixed
mode systems
- Fix the fallout of merging the 32bit and 64bit variants of EFI PCI
related code which ended up chosing the 32bit variant of the actual
EFi call invocation which leads to failures on 64bit"
* 'efi-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
efi/x86: Fix incorrect invocation of PciIo->Attributes()
efi/libstub/tpm: Initialize efi_physical_addr_t vars to zero for mixed mode
When delivering a signal to a task that is using rseq, we call into
__rseq_handle_notify_resume() so that the registers pushed in the
sigframe are updated to reflect the state of the restartable sequence
(for example, ensuring that the signal returns to the abort handler if
necessary).
However, if the rseq management fails due to an unrecoverable fault when
accessing userspace or certain combinations of RSEQ_CS_* flags, then we
will attempt to deliver a SIGSEGV. This has the potential for infinite
recursion if the rseq code continuously fails on signal delivery.
Avoid this problem by using force_sigsegv() instead of force_sig(), which
is explicitly designed to reset the SEGV handler to SIG_DFL in the case
of a recursive fault. In doing so, remove rseq_signal_deliver() from the
internal rseq API and have an optional struct ksignal * parameter to
rseq_handle_notify_resume() instead.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: peterz@infradead.org
Cc: paulmck@linux.vnet.ibm.com
Cc: boqun.feng@gmail.com
Link: https://lkml.kernel.org/r/1529664307-983-1-git-send-email-will.deacon@arm.com
insn_get_length() has the side-effect of processing the entire instruction
but only if it was decoded successfully, otherwise insn_complete() can fail
and in this case we need to just return an error without warning.
Reported-by: syzbot+30d675e3ca03c1c351e7@syzkaller.appspotmail.com
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: syzkaller-bugs@googlegroups.com
Link: https://lkml.kernel.org/lkml/20180518162739.GA5559@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull core fixes from Thomas Gleixner:
"Two tiny fixes:
- Add the missing machine_real_restart() to objtools noreturn list so
it stops complaining
- Fix a trivial comment typo"
* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
kernel.h: Fix a typo in comment
objtool: Add machine_real_restart() to the noreturn list
The following commit:
2c3625cb9fa2 ("efi/x86: Fold __setup_efi_pci32() and __setup_efi_pci64() into one function")
... merged the two versions of __setup_efi_pciXX(), without taking into
account that the 32-bit version used a rather dodgy trick to pass an
immediate 0 constant as argument for a uint64_t parameter.
The issue is caused by the fact that on x86, UEFI protocol method calls
are redirected via struct efi_config::call(), which is a variadic function,
and so the compiler has to infer the types of the parameters from the
arguments rather than from the prototype.
As the 32-bit x86 calling convention passes arguments via the stack,
passing the unqualified constant 0 twice is the same as passing 0ULL,
which is why the 32-bit code in __setup_efi_pci32() contained the
following call:
status = efi_early->call(pci->attributes, pci,
EfiPciIoAttributeOperationGet, 0, 0,
&attributes);
to invoke this UEFI protocol method:
typedef
EFI_STATUS
(EFIAPI *EFI_PCI_IO_PROTOCOL_ATTRIBUTES) (
IN EFI_PCI_IO_PROTOCOL *This,
IN EFI_PCI_IO_PROTOCOL_ATTRIBUTE_OPERATION Operation,
IN UINT64 Attributes,
OUT UINT64 *Result OPTIONAL
);
After the merge, we inadvertently ended up with this version for both
32-bit and 64-bit builds, breaking the latter.
So replace the two zeroes with the explicitly typed constant 0ULL,
which works as expected on both 32-bit and 64-bit builds.
Wilfried tested the 64-bit build, and I checked the generated assembly
of a 32-bit build with and without this patch, and they are identical.
Reported-by: Wilfried Klaebe <linux-kernel@lebenslange-mailadresse.de>
Tested-by: Wilfried Klaebe <linux-kernel@lebenslange-mailadresse.de>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: hdegoede@redhat.com
Cc: linux-efi@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Considering that we explicitly forbid system calls in rseq critical
sections, it is not valid to issue a fork or clone system call within a
rseq critical section, so rseq_fork() is not required to restart an
active rseq c.s. in the child process.
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Ben Maurer <bmaurer@fb.com>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Lameter <cl@linux.com>
Cc: Dave Watson <davejwatson@fb.com>
Cc: Joel Fernandes <joelaf@google.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Paul E . McKenney <paulmck@linux.vnet.ibm.com>
Cc: Paul Turner <pjt@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Shuah Khan <shuahkh@osg.samsung.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-api@vger.kernel.org
Cc: linux-kselftest@vger.kernel.org
Link: https://lore.kernel.org/lkml/20180619133230.4087-4-mathieu.desnoyers@efficios.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull perf/urgent fixes and improvements from Arnaldo Carvalho de Melo:
perf stat:
- Fix metric column header display alignment (Jiri Olsa)
- Improve error messages for default attributes, providing better output
for error in command lines such as:
$ perf stat -T
Cannot set up transaction events
event syntax error: '..cycles,cpu/cycles-t/,cpu/tx-start/,cpu/el-start/,cpu/cycles-ct/}'
\___ unknown term
Where the "event syntax error" line now appears (Jiri Olsa)
- Add --interval-clear option, to provide a 'watch' like printing (Jiri Olsa)
perf script:
- Show hw-cache events too (Seeteena Thoufeek)
perf c2c:
- Fix data dependency problem in layout of 'struct c2c_hist_entry', where
its member 'struct hist_entry' must be at the end because it has a ZLA
as its last member, that gets space when handling callchains (Jiri Olsa)
Core:
- We cannot assume that a 'struct perf_evsel' is to be obtained from a
container_of operation on a 'struct hists' as there are tools, such as
'perf c2c' that uses 'struct hist' instances without having them in
container structs that also have 'struct perf_evsel' in a particular
layout, so provide a different way of figuring out if a 'struct hists'
and 'struct hist_entry' have callchains (Arnaldo Carvalho de Melo)
- Fix error index in the PMU event parser, so that error messages can
point to the problematic token (Jiri Olsa)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Pull x86 fixes from Thomas Gleixner:
"A set of fixes for x86:
- Make Xen PV guest deal with speculative store bypass correctly
- Address more fallout from the 5-Level pagetable handling. Undo an
__initdata annotation to avoid section mismatch and malfunction
when post init code would touch the freed variable.
- Handle exception fixup in math_error() before calling notify_die().
The reverse call order incorrectly triggers notify_die() listeners
for soemthing which is handled correctly at the site which issues
the floating point instruction.
- Fix an off by one in the LLC topology calculation on AMD
- Handle non standard memory block sizes gracefully un UV platforms
- Plug a memory leak in the microcode loader
- Sanitize the purgatory build magic
- Add the x86 specific device tree bindings directory to the x86
MAINTAINER file patterns"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mm: Fix 'no5lvl' handling
Revert "x86/mm: Mark __pgtable_l5_enabled __initdata"
x86/CPU/AMD: Fix LLC ID bit-shift calculation
MAINTAINERS: Add file patterns for x86 device tree bindings
x86/microcode/intel: Fix memleak in save_microcode_patch()
x86/platform/UV: Add kernel parameter to set memory block size
x86/platform/UV: Use new set memory block size function
x86/platform/UV: Add adjustable set memory block size function
x86/build: Remove unnecessary preparation for purgatory
Revert "kexec/purgatory: Add clean-up for purgatory directory"
x86/xen: Add call of speculative_store_bypass_ht_init() to PV paths
x86: Call fixup_exception() before notify_die() in math_error()
Signed-off-by: Wei Wang <wvw@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Crt Mori <cmo@melexis.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: gregkh@linuxfoundation.org
Cc: wei.vince.wang@gmail.com
Link: https://lkml.kernel.org/lkml/20180424212241.16013-1-wvw@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Commit:
79832f0b5f71 ("efi/libstub/tpm: Initialize pointer variables to zero for mixed mode")
fixes a problem with the tpm code on mixed mode (64-bit kernel on 32-bit UEFI),
where 64-bit pointer variables are not fully initialized by the 32-bit EFI code.
A similar problem applies to the efi_physical_addr_t variables which
are written by the ->get_event_log() EFI call. Even though efi_physical_addr_t
is 64-bit everywhere, it seems that some 32-bit UEFI implementations only
fill in the lower 32 bits when passed a pointer to an efi_physical_addr_t
to fill.
This commit initializes these to 0 to, to ensure the upper 32 bits are
0 in mixed mode. This fixes recent kernels sometimes hanging during
early boot on mixed mode UEFI systems.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: <stable@vger.kernel.org> # v4.16+
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/20180622064222.11633-2-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
uapi/linux/rseq.h aligns 'struct rseq_cs' on 32 bytes. Satisfy this
alignment requirement in its definition within the rseq-arm.h
inline assembly as well.
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Hunter <ahh@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Ben Maurer <bmaurer@fb.com>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Lameter <cl@linux.com>
Cc: Dave Watson <davejwatson@fb.com>
Cc: Joel Fernandes <joelaf@google.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Paul E . McKenney <paulmck@linux.vnet.ibm.com>
Cc: Paul Turner <pjt@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Shuah Khan <shuahkh@osg.samsung.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-api@vger.kernel.org
Cc: linux-kselftest@vger.kernel.org
Link: https://lore.kernel.org/lkml/20180619133230.4087-3-mathieu.desnoyers@efficios.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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