Merge the state of the locking kcsan branch before the read/write_once()
and the atomics modifications got merged.
Squash the fallout of the rebase on top of the read/write once and atomic
fallback work into the merge. The history of the original branch is
preserved in tag locking-kcsan-2020-06-02.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Pull nfsd updates from Bruce Fields:
"Highlights:
- Keep nfsd clients from unnecessarily breaking their own
delegations.
Note this requires a small kthreadd addition. The result is Tejun
Heo's suggestion (see link), and he was OK with this going through
my tree.
- Patch nfsd/clients/ to display filenames, and to fix byte-order
when displaying stateid's.
- fix a module loading/unloading bug, from Neil Brown.
- A big series from Chuck Lever with RPC/RDMA and tracing
improvements, and lay some groundwork for RPC-over-TLS"
Link: https://lore.kernel.org/r/1588348912-24781-1-git-send-email-bfields@redhat.com
* tag 'nfsd-5.8' of git://linux-nfs.org/~bfields/linux: (49 commits)
sunrpc: use kmemdup_nul() in gssp_stringify()
nfsd: safer handling of corrupted c_type
nfsd4: make drc_slab global, not per-net
SUNRPC: Remove unreachable error condition in rpcb_getport_async()
nfsd: Fix svc_xprt refcnt leak when setup callback client failed
sunrpc: clean up properly in gss_mech_unregister()
sunrpc: svcauth_gss_register_pseudoflavor must reject duplicate registrations.
sunrpc: check that domain table is empty at module unload.
NFSD: Fix improperly-formatted Doxygen comments
NFSD: Squash an annoying compiler warning
SUNRPC: Clean up request deferral tracepoints
NFSD: Add tracepoints for monitoring NFSD callbacks
NFSD: Add tracepoints to the NFSD state management code
NFSD: Add tracepoints to NFSD's duplicate reply cache
SUNRPC: svc_show_status() macro should have enum definitions
SUNRPC: Restructure svc_udp_recvfrom()
SUNRPC: Refactor svc_recvfrom()
SUNRPC: Clean up svc_release_skb() functions
SUNRPC: Refactor recvfrom path dealing with incomplete TCP receives
SUNRPC: Replace dprintk() call sites in TCP receive path
...
The typical pattern for trace_hardirqs_off_prepare() is:
ENTRY
lockdep_hardirqs_off(); // because hardware
... do entry magic
instrumentation_begin();
trace_hardirqs_off_prepare();
... do actual work
trace_hardirqs_on_prepare();
lockdep_hardirqs_on_prepare();
instrumentation_end();
... do exit magic
lockdep_hardirqs_on();
which shows that it's named wrong, rename it to
trace_hardirqs_off_finish(), as it concludes the hardirq_off transition.
Also, given that the above is the only correct order, make the traditional
all-in-one trace_hardirqs_off() follow suit.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200529213321.415774872@infradead.org
Because:
irq_enter_rcu() includes lockdep_hardirq_enter()
irq_exit_rcu() does *NOT* include lockdep_hardirq_exit()
Which resulted in two 'stray' lockdep_hardirq_exit() calls in
idtentry.h, and me spending a long time trying to find the matching
enter calls.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200529213321.359433429@infradead.org
Mark the relevant functions noinstr, use the plain non-instrumented MSR
accessors. The only odd part is the instrumentation_begin()/end() pair around the
indirect machine_check_vector() call as objtool can't figure that out. The
possible invoked functions are annotated correctly.
Also use notrace variant of nmi_enter/exit(). If MCEs happen then hardware
latency tracing is the least of the worries.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Andy Lutomirski <luto@kernel.org>
Link: https://lkml.kernel.org/r/20200505135315.476734898@linutronix.de
context tracking lacks a few protection mechanisms against instrumentation:
- While the core functions are marked NOKPROBE they lack protection
against function tracing which is required as the function entry/exit
points can be utilized by BPF.
- static functions invoked from the protected functions need to be marked
as well as they can be instrumented otherwise.
- using plain inline allows the compiler to emit traceable and probable
functions.
Fix this by marking the functions noinstr and converting the plain inlines
to __always_inline.
The NOKPROBE_SYMBOL() annotations are removed as the .noinstr.text section
is already excluded from being probed.
Cures the following objtool warnings:
vmlinux.o: warning: objtool: enter_from_user_mode()+0x34: call to __context_tracking_exit() leaves .noinstr.text section
vmlinux.o: warning: objtool: prepare_exit_to_usermode()+0x29: call to __context_tracking_enter() leaves .noinstr.text section
vmlinux.o: warning: objtool: syscall_return_slowpath()+0x29: call to __context_tracking_enter() leaves .noinstr.text section
vmlinux.o: warning: objtool: do_syscall_64()+0x7f: call to __context_tracking_enter() leaves .noinstr.text section
vmlinux.o: warning: objtool: do_int80_syscall_32()+0x3d: call to __context_tracking_enter() leaves .noinstr.text section
vmlinux.o: warning: objtool: do_fast_syscall_32()+0x9c: call to __context_tracking_enter() leaves .noinstr.text section
and generates new ones...
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200505134340.811520478@linutronix.de
kdb has to get messages on consoles even when the system is stopped.
It uses kdb_printf() internally and calls console drivers on its own.
It uses a hack to reuse an existing code. It sets "kdb_trap_printk"
global variable to redirect even the normal printk() into the
kdb_printf() variant.
The variable "kdb_trap_printk" is checked in printk_default() and
it is ignored when printk is redirected to printk_safe in NMI context.
Solve this by moving the check into printk_func().
It is obvious that it is not fully safe. But it does not make things
worse. The console drivers are already called in this context by
db_printf() direct calls.
Reported-by: Sumit Garg <sumit.garg@linaro.org>
Tested-by: Sumit Garg <sumit.garg@linaro.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Acked-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20200520102233.GC3464@linux-b0ei
kcov_remote_stop() should check that the corresponding kcov_remote_start()
actually found the specified remote handle and started collecting
coverage. This is done by checking the per thread kcov_softirq flag.
A particular failure scenario where this was observed involved a softirq
with a remote coverage collection section coming between check_kcov_mode()
and the access to t->kcov_area in __sanitizer_cov_trace_pc(). In that
softirq kcov_remote_start() bailed out after kcov_remote_find() check, but
the matching kcov_remote_stop() didn't check if kcov_remote_start()
succeeded, and overwrote per thread kcov parameters with invalid (zero)
values.
Fixes: 5ff3b30ab5 ("kcov: collect coverage from interrupts")
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Marco Elver <elver@google.com>
Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Link: http://lkml.kernel.org/r/fcd1cd16eac1d2c01a66befd8ea4afc6f8d09833.1591576806.git.andreyknvl@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull sysctl fixes from Al Viro:
"Fixups to regressions in sysctl series"
* 'work.sysctl' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
sysctl: reject gigantic reads/write to sysctl files
cdrom: fix an incorrect __user annotation on cdrom_sysctl_info
trace: fix an incorrect __user annotation on stack_trace_sysctl
random: fix an incorrect __user annotation on proc_do_entropy
net/sysctl: remove leftover __user annotations on neigh_proc_dointvec*
net/sysctl: use cpumask_parse in flow_limit_cpu_sysctl
Pull misc uaccess updates from Al Viro:
"Assorted uaccess patches for this cycle - the stuff that didn't fit
into thematic series"
* 'uaccess.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
bpf: make bpf_check_uarg_tail_zero() use check_zeroed_user()
x86: kvm_hv_set_msr(): use __put_user() instead of 32bit __clear_user()
user_regset_copyout_zero(): use clear_user()
TEST_ACCESS_OK _never_ had been checked anywhere
x86: switch cp_stat64() to unsafe_put_user()
binfmt_flat: don't use __put_user()
binfmt_elf_fdpic: don't use __... uaccess primitives
binfmt_elf: don't bother with __{put,copy_to}_user()
pselect6() and friends: take handling the combined 6th/7th args into helper
Pull READ/WRITE_ONCE rework from Will Deacon:
"This the READ_ONCE rework I've been working on for a while, which
bumps the minimum GCC version and improves code-gen on arm64 when
stack protector is enabled"
[ Side note: I'm _really_ tempted to raise the minimum gcc version to
4.9, so that we can just say that we require _Generic() support.
That would allow us to more cleanly handle a lot of the cases where we
depend on very complex macros with 'sizeof' or __builtin_choose_expr()
with __builtin_types_compatible_p() etc.
This branch has a workaround for sparse not handling _Generic(),
either, but that was already fixed in the sparse development branch,
so it's really just gcc-4.9 that we'd require. - Linus ]
* 'rwonce/rework' of git://git.kernel.org/pub/scm/linux/kernel/git/will/linux:
compiler_types.h: Use unoptimized __unqual_scalar_typeof for sparse
compiler_types.h: Optimize __unqual_scalar_typeof compilation time
compiler.h: Enforce that READ_ONCE_NOCHECK() access size is sizeof(long)
compiler-types.h: Include naked type in __pick_integer_type() match
READ_ONCE: Fix comment describing 2x32-bit atomicity
gcov: Remove old GCC 3.4 support
arm64: barrier: Use '__unqual_scalar_typeof' for acquire/release macros
locking/barriers: Use '__unqual_scalar_typeof' for load-acquire macros
READ_ONCE: Drop pointer qualifiers when reading from scalar types
READ_ONCE: Enforce atomicity for {READ,WRITE}_ONCE() memory accesses
READ_ONCE: Simplify implementations of {READ,WRITE}_ONCE()
arm64: csum: Disable KASAN for do_csum()
fault_inject: Don't rely on "return value" from WRITE_ONCE()
net: tls: Avoid assigning 'const' pointer to non-const pointer
netfilter: Avoid assigning 'const' pointer to non-const pointer
compiler/gcc: Raise minimum GCC version for kernel builds to 4.8
Pull more power management updates from Rafael Wysocki:
"These are operating performance points (OPP) framework updates mostly,
including support for interconnect bandwidth in the OPP core, plus a
few cpufreq changes, including boost support in the CPPC cpufreq
driver, an ACPI device power management fix and a hibernation code
cleanup.
Specifics:
- Add support for interconnect bandwidth to the OPP core (Georgi
Djakov, Saravana Kannan, Sibi Sankar, Viresh Kumar).
- Add support for regulator enable/disable to the OPP core (Kamil
Konieczny).
- Add boost support to the CPPC cpufreq driver (Xiongfeng Wang).
- Make the tegra186 cpufreq driver set the
CPUFREQ_NEED_INITIAL_FREQ_CHECK flag (Mian Yousaf Kaukab).
- Prevent the ACPI power management from using power resources with
devices where the list of power resources for power state D0 (full
power) is missing (Rafael Wysocki).
- Annotate a hibernation-related function with __init (Christophe
JAILLET)"
* tag 'pm-5.8-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
ACPI: PM: Avoid using power resources if there are none for D0
cpufreq: CPPC: add SW BOOST support
cpufreq: change '.set_boost' to act on one policy
PM: hibernate: Add __init annotation to swsusp_header_init()
opp: Don't parse icc paths unnecessarily
opp: Remove bandwidth votes when target_freq is zero
opp: core: add regulators enable and disable
opp: Reorder the code for !target_freq case
opp: Expose bandwidth information via debugfs
cpufreq: dt: Add support for interconnect bandwidth scaling
opp: Update the bandwidth on OPP frequency changes
opp: Add sanity checks in _read_opp_key()
opp: Add support for parsing interconnect bandwidth
cpufreq: tegra186: add CPUFREQ_NEED_INITIAL_FREQ_CHECK flag
OPP: Add helpers for reading the binding properties
dt-bindings: opp: Introduce opp-peak-kBps and opp-avg-kBps bindings
V2:
- Defer changing BPF-syscall to start at file-descriptor 1
- Use {} to zero initialise struct.
The recent commit fbee97feed ("bpf: Add support to attach bpf program to a
devmap entry"), introduced ability to attach (and run) a separate XDP
bpf_prog for each devmap entry. A bpf_prog is added via a file-descriptor.
As zero were a valid FD, not using the feature requires using value minus-1.
The UAPI is extended via tail-extending struct bpf_devmap_val and using
map->value_size to determine the feature set.
This will break older userspace applications not using the bpf_prog feature.
Consider an old userspace app that is compiled against newer kernel
uapi/bpf.h, it will not know that it need to initialise the member
bpf_prog.fd to minus-1. Thus, users will be forced to update source code to
get program running on newer kernels.
This patch remove the minus-1 checks, and have zero mean feature isn't used.
Followup patches either for kernel or libbpf should handle and avoid
returning file-descriptor zero in the first place.
Fixes: fbee97feed ("bpf: Add support to attach bpf program to a devmap entry")
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/159170950687.2102545.7235914718298050113.stgit@firesoul
When using BPF_PROG_ATTACH to attach a program to a cgroup in
BPF_F_ALLOW_MULTI mode, it is not possible to replace a program
with itself. This is because the check for duplicate programs
doesn't take the replacement program into account.
Replacing a program with itself might seem weird, but it has
some uses: first, it allows resetting the associated cgroup storage.
Second, it makes the API consistent with the non-ALLOW_MULTI usage,
where it is possible to replace a program with itself. Third, it
aligns BPF_PROG_ATTACH with bpf_link, where replacing itself is
also supported.
Sice this code has been refactored a few times this change will
only apply to v5.7 and later. Adjustments could be made to
commit 1020c1f24a ("bpf: Simplify __cgroup_bpf_attach") and
commit d7bf2c10af ("bpf: allocate cgroup storage entries on attaching bpf programs")
as well as commit 324bda9e6c ("bpf: multi program support for cgroup+bpf")
Fixes: af6eea5743 ("bpf: Implement bpf_link-based cgroup BPF program attachment")
Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200608162202.94002-1-lmb@cloudflare.com
Commit 60d53e2c3b ("tracing/probe: Split trace_event related data from
trace_probe") removed the trace_[ku]probe structure from the
trace_event_call->data pointer. As bpf_get_[ku]probe_info() were
forgotten in that change, fix them now. These functions are currently
only used by the bpf_task_fd_query() syscall handler to collect
information about a perf event.
Fixes: 60d53e2c3b ("tracing/probe: Split trace_event related data from trace_probe")
Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Link: https://lore.kernel.org/bpf/20200608124531.819838-1-jean-philippe@linaro.org
Pull tracing updates from Steven Rostedt:
"No new features this release. Mostly clean ups, restructuring and
documentation.
- Have ftrace_bug() show ftrace errors before the WARN, as the WARN
will reboot the box before the error messages are printed if
panic_on_warn is set.
- Have traceoff_on_warn disable tracing sooner (before prints)
- Write a message to the trace buffer that its being disabled when
disable_trace_on_warning() is set.
- Separate out synthetic events from histogram code to let it be used
by other parts of the kernel.
- More documentation on histogram design.
- Other small fixes and clean ups"
* tag 'trace-v5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Remove obsolete PREEMPTIRQ_EVENTS kconfig option
tracing/doc: Fix ascii-art in histogram-design.rst
tracing: Add a trace print when traceoff_on_warning is triggered
ftrace,bug: Improve traceoff_on_warn
selftests/ftrace: Distinguish between hist and synthetic event checks
tracing: Move synthetic events to a separate file
tracing: Fix events.rst section numbering
tracing/doc: Fix typos in histogram-design.rst
tracing: Add hist_debug trace event files for histogram debugging
tracing: Add histogram-design document
tracing: Check state.disabled in synth event trace functions
tracing/probe: reverse arguments to list_add
tools/bootconfig: Add a summary of test cases and return error
ftrace: show debugging information when panic_on_warn set
Merge even more updates from Andrew Morton:
- a kernel-wide sweep of show_stack()
- pagetable cleanups
- abstract out accesses to mmap_sem - prep for mmap_sem scalability work
- hch's user acess work
Subsystems affected by this patch series: debug, mm/pagemap, mm/maccess,
mm/documentation.
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (93 commits)
include/linux/cache.h: expand documentation over __read_mostly
maccess: return -ERANGE when probe_kernel_read() fails
x86: use non-set_fs based maccess routines
maccess: allow architectures to provide kernel probing directly
maccess: move user access routines together
maccess: always use strict semantics for probe_kernel_read
maccess: remove strncpy_from_unsafe
tracing/kprobes: handle mixed kernel/userspace probes better
bpf: rework the compat kernel probe handling
bpf:bpf_seq_printf(): handle potentially unsafe format string better
bpf: handle the compat string in bpf_trace_copy_string better
bpf: factor out a bpf_trace_copy_string helper
maccess: unify the probe kernel arch hooks
maccess: remove probe_read_common and probe_write_common
maccess: rename strnlen_unsafe_user to strnlen_user_nofault
maccess: rename strncpy_from_unsafe_strict to strncpy_from_kernel_nofault
maccess: rename strncpy_from_unsafe_user to strncpy_from_user_nofault
maccess: update the top of file comment
maccess: clarify kerneldoc comments
maccess: remove duplicate kerneldoc comments
...
uprobe_write_opcode() must not cross page boundary; prepare_uprobe()
relies on arch_uprobe_analyze_insn() which should validate "vaddr" but
some architectures (csky, s390, and sparc) don't do this.
We can remove the BUG_ON() check in prepare_uprobe() and validate the
offset early in __uprobe_register(). The new IS_ALIGNED() check matches
the alignment check in arch_prepare_kprobe() on supported architectures,
so I think that all insns must be aligned to UPROBE_SWBP_INSN_SIZE.
Another problem is __update_ref_ctr() which was wrong from the very
beginning, it can read/write outside of kmap'ed page unless "vaddr" is
aligned to sizeof(short), __uprobe_register() should check this too.
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Tested-by: Sven Schnelle <svens@linux.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Except for historical confusion in the kprobes/uprobes and bpf tracers,
which has been fixed now, there is no good reason to ever allow user
memory accesses from probe_kernel_read. Switch probe_kernel_read to only
read from kernel memory.
[akpm@linux-foundation.org: update it for "mm, dump_page(): do not crash with invalid mapping pointer"]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20200521152301.2587579-17-hch@lst.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Print the stack trace with KERN_EMERG - it should be always visible.
Playing with console_loglevel is a bad idea as there may be more messages
printed than wanted. Also the stack trace might be not printed at all if
printk() was deferred and console_loglevel was raised back before the
trace got flushed.
Unfortunately, after rebasing on commit 2277b49258 ("kdb: Fix stack
crawling on 'running' CPUs that aren't the master"), kdb_show_stack() uses
now kdb_dump_stack_on_cpu(), which for now won't be converted as it uses
dump_stack() instead of show_stack().
Convert for now the branch that uses show_stack() and remove
console_loglevel exercise from that case.
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Cc: Jason Wessel <jason.wessel@windriver.com>
Link: http://lkml.kernel.org/r/20200418201944.482088-48-dima@arista.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
CONFIG_GENERIC_VDSO_CLOCK_MODE was a transitional config switch which got
removed after all architectures got converted to the new storage model.
But the removal forgot to remove the #ifdef which guards the
vdso_clock_mode sanity check, which effectively disables the sanity check.
Remove it now.
Fixes: f86fd32db7 ("lib/vdso: Cleanup clock mode storage leftovers")
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Miklos Szeredi <mszeredi@redhat.com>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20200606221531.845475036@linutronix.de
On systems with at least 32 MiB, but less than 32 GiB of RAM, the DMA
memory pools are much larger than intended (e.g. 2 MiB instead of 128
KiB on a 256 MiB system).
Fix this by correcting the calculation of the number of GiBs of RAM in
the system. Invert the order of the min/max operations, to keep on
calculating in pages until the last step, which aids readability.
Fixes: 1d659236fb ("dma-pool: scale the default DMA coherent pool size with memory capacity")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
