Thomas Gleixner [Tue, 25 Feb 2020 22:16:16 +0000 (23:16 +0100)]
x86/entry: Convert INT3 exception to IDTENTRY_RAW
Convert #BP to IDTENTRY_RAW:
- Implement the C entry point with DEFINE_IDTENTRY_RAW
- Invoke idtentry_enter/exit() from the function body
- Emit the ASM stub with DECLARE_IDTENTRY_RAW
- Remove the ASM idtentry in 64bit
- Remove the open coded ASM entry code in 32bit
- Fixup the XEN/PV code
- Remove the old prototypes
No functional change.
This could be a plain IDTENTRY, but as Peter pointed out INT3 is broken
vs. the static key in the context tracking code as this static key might be
in the state of being patched and has an int3 which would recurse forever.
IDTENTRY_RAW is therefore chosen to allow addressing this issue without
lots of code churn.
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/20200505135313.938474960@linutronix.de
Peter Zijlstra [Thu, 20 Feb 2020 12:28:06 +0000 (13:28 +0100)]
x86/int3: Inline bsearch()
Avoid calling out to bsearch() by inlining it, for normal kernel configs
this was the last external call and poke_int3_handler() is now fully self
sufficient -- no calls to external code.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com> Acked-by: Andy Lutomirski <luto@kernel.org> Link: https://lkml.kernel.org/r/20200505135313.731774429@linutronix.de
Peter Zijlstra [Wed, 19 Feb 2020 17:25:09 +0000 (18:25 +0100)]
lib/bsearch: Provide __always_inline variant
For code that needs the ultimate performance (it can inline the @cmp
function too) or simply needs to avoid calling external functions for
whatever reason, provide an __always_inline variant of bsearch().
[ tglx: Renamed to __inline_bsearch() as suggested by Andy ]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com> Acked-by: Andy Lutomirski <luto@kernel.org> Link: https://lkml.kernel.org/r/20200505135313.624443814@linutronix.de
Thomas Gleixner [Tue, 21 Jan 2020 14:53:09 +0000 (15:53 +0100)]
x86/int3: Ensure that poke_int3_handler() is not traced
In order to ensure poke_int3_handler() is completely self contained -- this
is called while modifying other text, imagine the fun of hitting another
INT3 -- ensure that everything it uses is not traced.
The primary means here is to force inlining; bsearch() is notrace because
all of lib/ is.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com> Acked-by: Andy Lutomirski <luto@kernel.org> Link: https://lkml.kernel.org/r/20200505135313.410702173@linutronix.de
Thomas Gleixner [Tue, 25 Feb 2020 22:16:30 +0000 (23:16 +0100)]
x86/entry/32: Convert IRET exception to IDTENTRY_SW
Convert the IRET exception handler to IDTENTRY_SW. This is slightly
different than the conversions of hardware exceptions as the IRET exception
is invoked via an exception table when IRET faults. So it just uses the
IDTENTRY_SW mechanism for consistency. It does not emit ASM code as it does
not fit the other idtentry exceptions.
- Implement the C entry point with DEFINE_IDTENTRY_SW() which maps to
DEFINE_IDTENTRY()
- Fixup the XEN/PV code
- Remove the old prototypes
- Remove the RCU warning as the new entry macro ensures correctness
No functional change.
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/20200505134906.128769226@linutronix.de
Thomas Gleixner [Tue, 25 Feb 2020 22:16:29 +0000 (23:16 +0100)]
x86/entry: Convert SIMD coprocessor error exception to IDTENTRY
Convert #XF to IDTENTRY_ERRORCODE:
- Implement the C entry point with DEFINE_IDTENTRY
- Emit the ASM stub with DECLARE_IDTENTRY
- Handle INVD_BUG in C
- Remove the ASM idtentry in 64bit
- Remove the open coded ASM entry code in 32bit
- Fixup the XEN/PV code
- Remove the old prototypes
- Remove the RCU warning as the new entry macro ensures correctness
No functional change.
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/20200505134906.021552202@linutronix.de
Thomas Gleixner [Tue, 25 Feb 2020 22:16:28 +0000 (23:16 +0100)]
x86/entry: Convert Alignment check exception to IDTENTRY
Convert #AC to IDTENTRY_ERRORCODE:
- Implement the C entry point with DEFINE_IDTENTRY
- Emit the ASM stub with DECLARE_IDTENTRY
- Remove the ASM idtentry in 64bit
- Remove the open coded ASM entry code in 32bit
- Fixup the XEN/PV code
- Remove the old prototypes
- Remove the RCU warning as the new entry macro ensures correctness
No functional change.
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/20200505134905.928967113@linutronix.de
Thomas Gleixner [Tue, 25 Feb 2020 22:16:27 +0000 (23:16 +0100)]
x86/entry: Convert Coprocessor error exception to IDTENTRY
Convert #MF to IDTENTRY_ERRORCODE:
- Implement the C entry point with DEFINE_IDTENTRY
- Emit the ASM stub with DECLARE_IDTENTRY
- Remove the ASM idtentry in 64bit
- Remove the open coded ASM entry code in 32bit
- Fixup the XEN/PV code
- Remove the old prototypes
- Remove the RCU warning as the new entry macro ensures correctness
No functional change.
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/20200505134905.838823510@linutronix.de
Thomas Gleixner [Tue, 25 Feb 2020 22:16:26 +0000 (23:16 +0100)]
x86/entry: Convert Spurious interrupt bug exception to IDTENTRY
Convert #SPURIOUS to IDTENTRY_ERRORCODE:
- Implement the C entry point with DEFINE_IDTENTRY
- Emit the ASM stub with DECLARE_IDTENTRY
- Remove the ASM idtentry in 64bit
- Remove the open coded ASM entry code in 32bit
- Fixup the XEN/PV code
- Remove the old prototypes
No functional change.
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/20200505134905.728077036@linutronix.de
Thomas Gleixner [Tue, 25 Feb 2020 22:16:25 +0000 (23:16 +0100)]
x86/entry: Convert General protection exception to IDTENTRY
Convert #GP to IDTENTRY_ERRORCODE:
- Implement the C entry point with DEFINE_IDTENTRY
- Emit the ASM stub with DECLARE_IDTENTRY
- Remove the ASM idtentry in 64bit
- Remove the open coded ASM entry code in 32bit
- Fixup the XEN/PV code
- Remove the old prototypes
- Remove the RCU warning as the new entry macro ensures correctness
No functional change.
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/20200505134905.637269946@linutronix.de
Thomas Gleixner [Tue, 25 Feb 2020 22:16:24 +0000 (23:16 +0100)]
x86/entry: Convert Stack segment exception to IDTENTRY
Convert #SS to IDTENTRY_ERRORCODE:
- Implement the C entry point with DEFINE_IDTENTRY
- Emit the ASM stub with DECLARE_IDTENTRY
- Remove the ASM idtentry in 64bit
- Remove the open coded ASM entry code in 32bit
- Fixup the XEN/PV code
- Remove the old prototypes
No functional change.
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/20200505134905.539867572@linutronix.de
Thomas Gleixner [Tue, 25 Feb 2020 22:16:23 +0000 (23:16 +0100)]
x86/entry: Convert Segment not present exception to IDTENTRY
Convert #NP to IDTENTRY_ERRORCODE:
- Implement the C entry point with DEFINE_IDTENTRY
- Emit the ASM stub with DECLARE_IDTENTRY
- Remove the ASM idtentry in 64bit
- Remove the open coded ASM entry code in 32bit
- Fixup the XEN/PV code
- Remove the old prototypes
No functional change.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com> Acked-by: Andy Lutomirski <luto@kernel.org> Acked-by: Peter Zijlstra <peterz@infradead.org> Link: https://lkml.kernel.org/r/20200505134905.443591450@linutronix.de
Thomas Gleixner [Tue, 25 Feb 2020 22:16:22 +0000 (23:16 +0100)]
x86/entry: Convert Invalid TSS exception to IDTENTRY
Convert #TS to IDTENTRY_ERRORCODE:
- Implement the C entry point with DEFINE_IDTENTRY
- Emit the ASM stub with DECLARE_IDTENTRY
- Remove the ASM idtentry in 64bit
- Remove the open coded ASM entry code in 32bit
- Fixup the XEN/PV code
- Remove the old prototypes
No functional change.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com> Acked-by: Andy Lutomirski <luto@kernel.org> Acked-by: Peter Zijlstra <peterz@infradead.org> Link: https://lkml.kernel.org/r/20200505134905.350676449@linutronix.de
Thomas Gleixner [Tue, 25 Feb 2020 22:16:20 +0000 (23:16 +0100)]
x86/entry: Convert Coprocessor segment overrun exception to IDTENTRY
Convert #OLD_MF to IDTENTRY:
- Implement the C entry point with DEFINE_IDTENTRY
- Emit the ASM stub with DECLARE_IDTENTRY
- Remove the ASM idtentry in 64bit
- Remove the open coded ASM entry code in 32bit
- Fixup the XEN/PV code
- Remove the old prototypes
No functional change.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com> Acked-by: Andy Lutomirski <luto@kernel.org> Acked-by: Peter Zijlstra <peterz@infradead.org> Link: https://lkml.kernel.org/r/20200505134905.838823510@linutronix.de
Thomas Gleixner [Tue, 25 Feb 2020 22:16:19 +0000 (23:16 +0100)]
x86/entry: Convert Device not available exception to IDTENTRY
Convert #NM to IDTENTRY:
- Implement the C entry point with DEFINE_IDTENTRY
- Emit the ASM stub with DECLARE_IDTENTRY
- Remove the ASM idtentry in 64bit
- Remove the open coded ASM entry code in 32bit
- Fixup the XEN/PV code
- Remove the old prototypes
- Remove the RCU warning as the new entry macro ensures correctness
No functional change.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com> Acked-by: Andy Lutomirski <luto@kernel.org> Acked-by: Peter Zijlstra <peterz@infradead.org> Link: https://lkml.kernel.org/r/20200505134905.056243863@linutronix.de
Thomas Gleixner [Tue, 25 Feb 2020 22:16:18 +0000 (23:16 +0100)]
x86/entry: Convert Invalid Opcode exception to IDTENTRY
Convert #UD to IDTENTRY:
- Implement the C entry point with DEFINE_IDTENTRY
- Emit the ASM stub with DECLARE_IDTENTRY
- Remove the ASM idtentry in 64bit
- Remove the open coded ASM entry code in 32bit
- Fixup the XEN/PV code
- Fixup the FOOF bug call in fault.c
- Remove the old prototypes
No functional change.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com> Acked-by: Andy Lutomirski <luto@kernel.org> Acked-by: Peter Zijlstra <peterz@infradead.org> Link: https://lkml.kernel.org/r/20200505134904.955511913@linutronix.de
Thomas Gleixner [Tue, 25 Feb 2020 22:16:17 +0000 (23:16 +0100)]
x86/entry: Convert Bounds exception to IDTENTRY
Convert #BR to IDTENTRY:
- Implement the C entry point with DEFINE_IDTENTRY
- Emit the ASM stub with DECLARE_IDTENTRY
- Remove the ASM idtentry in 64bit
- Remove the open coded ASM entry code in 32bit
- Fixup the XEN/PV code
- Remove the old prototypes
- Remove the RCU warning as the new entry macro ensures correctness
No functional change.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com> Acked-by: Andy Lutomirski <luto@kernel.org> Acked-by: Peter Zijlstra <peterz@infradead.org> Link: https://lkml.kernel.org/r/20200505134904.863001309@linutronix.de
Thomas Gleixner [Tue, 25 Feb 2020 22:16:15 +0000 (23:16 +0100)]
x86/entry: Convert Overflow exception to IDTENTRY
Convert #OF to IDTENTRY:
- Implement the C entry point with DEFINE_IDTENTRY
- Emit the ASM stub with DECLARE_IDTENTRY
- Remove the ASM idtentry in 64bit
- Remove the open coded ASM entry code in 32bit
- Fixup the XEN/PV code
- Remove the old prototypes
No functional change.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com> Acked-by: Andy Lutomirski <luto@kernel.org> Acked-by: Peter Zijlstra <peterz@infradead.org> Link: https://lkml.kernel.org/r/20200505134904.771457898@linutronix.de
Thomas Gleixner [Tue, 25 Feb 2020 22:16:14 +0000 (23:16 +0100)]
x86/entry: Convert Divide Error to IDTENTRY
Convert #DE to IDTENTRY:
- Implement the C entry point with DEFINE_IDTENTRY
- Emit the ASM stub with DECLARE_IDTENTRY
- Remove the ASM idtentry in 64bit
- Remove the open coded ASM entry code in 32bit
- Fixup the XEN/PV code
No functional change.
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/20200505134904.663914713@linutronix.de
Thomas Gleixner [Tue, 25 Feb 2020 22:16:13 +0000 (23:16 +0100)]
x86/traps: Prepare for using DEFINE_IDTENTRY
Prepare for using IDTENTRY to define the C exception/trap entry points. It
would be possible to glue this into the existing macro maze, but it's
simpler and better to read at the end to just make them distinct.
Provide a trivial inline helper to read the trap address and add a comment
explaining the logic behind it.
The existing macros will be removed once all instances are converted.
Thomas Gleixner [Tue, 25 Feb 2020 22:16:12 +0000 (23:16 +0100)]
x86/idtentry: Provide macros to define/declare IDT entry points
Provide DECLARE/DEFINE_IDTENTRY() macros.
DEFINE_IDTENTRY() provides a wrapper which acts as the function
definition. The exception handler body is just appended to it with curly
brackets. The entry point is marked noinstr so that irq tracing and the
enter_from_user_mode() can be moved into the C-entry point. As all
C-entries use the same macro (or a later variant) the necessary entry
handling can be implemented at one central place.
DECLARE_IDTENTRY() provides the function prototypes:
- The C entry point cfunc
- The ASM entry point asm_cfunc
- The XEN/PV entry point xen_asm_cfunc
They all follow the same naming convention.
When included from ASM code DECLARE_IDTENTRY() is a macro which emits the
low level entry point in assembly by instantiating idtentry.
IDTENTRY is the simplest variant which just has a pt_regs argument. It's
going to be used for all exceptions which have no error code.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com> Acked-by: Andy Lutomirski <luto@kernel.org> Acked-by: Peter Zijlstra <peterz@infradead.org> Link: https://lkml.kernel.org/r/20200505134904.273363275@linutronix.de
Thomas Gleixner [Wed, 23 Oct 2019 12:27:10 +0000 (14:27 +0200)]
x86/traps: Make interrupt enable/disable symmetric in C code
Traps enable interrupts conditionally but rely on the ASM return code to
disable them again. That results in redundant interrupt disable and trace
calls.
Make the trap handlers disable interrupts before returning to avoid that,
which allows simplification of the ASM entry code in follow up changes.
Originally-by: Peter Zijlstra <peterz@infradead.org> 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/20200505134903.622702796@linutronix.de
Thomas Gleixner [Wed, 4 Mar 2020 11:49:18 +0000 (12:49 +0100)]
x86/speculation/mds: Mark mds_user_clear_cpu_buffers() __always_inline
Prevent the compiler from uninlining and creating traceable/probable
functions as this is invoked _after_ context tracking switched to
CONTEXT_USER and rcu idle.
Thomas Gleixner [Wed, 4 Mar 2020 11:51:59 +0000 (12:51 +0100)]
x86/entry: Move irq flags tracing to prepare_exit_to_usermode()
This is another step towards more C-code and less convoluted ASM.
Similar to the entry path, invoke the tracer before context tracking which
might turn off RCU and invoke lockdep as the last step before going back to
user space. Annotate the code sections in exit_to_user_mode() accordingly
so objtool won't complain about the tracer invocation.
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/20200505134340.703783926@linutronix.de
Thomas Gleixner [Tue, 25 Feb 2020 22:08:05 +0000 (23:08 +0100)]
x86/entry: Move irq tracing on syscall entry to C-code
Now that the C entry points are safe, move the irq flags tracing code into
the entry helper:
- Invoke lockdep before calling into context tracking
- Use the safe trace_hardirqs_on_prepare() trace function after context
tracking established state and RCU is watching.
enter_from_user_mode() is also still invoked from the exception/interrupt
entry code which still contains the ASM irq flags tracing. So this is just
a redundant and harmless invocation of tracing / lockdep until these are
removed as well.
Thomas Gleixner [Tue, 10 Mar 2020 13:46:27 +0000 (14:46 +0100)]
x86/entry/common: Protect against instrumentation
Mark the various syscall entries with noinstr to protect them against
instrumentation and add the noinstrumentation_begin()/end() annotations to mark the
parts of the functions which are safe to call out into instrumentable code.
Thomas Gleixner [Sat, 29 Feb 2020 14:12:33 +0000 (15:12 +0100)]
x86/entry: Mark enter_from_user_mode() noinstr
Both the callers in the low level ASM code and __context_tracking_exit()
which is invoked from enter_from_user_mode() via user_exit_irqoff() are
marked NOKPROBE. Allowing enter_from_user_mode() to be probed is
inconsistent at best.
Aside of that while function tracing per se is safe the function trace
entry/exit points can be used via BPF as well which is not safe to use
before context tracking has reached CONTEXT_KERNEL and adjusted RCU.
Mark it noinstr which moves it into the instrumentation protected text
section and includes notrace.
Note, this needs further fixups in context tracking to ensure that the
full call chain is protected. Will be addressed in follow up changes.
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/20200505134340.429059405@linutronix.de
Thomas Gleixner [Wed, 25 Mar 2020 18:47:40 +0000 (19:47 +0100)]
x86/entry/32: Move non entry code into .text section
All ASM code which is not part of the entry functionality can move out into
the .text section. No reason to keep it in the non-instrumentable entry
section.
Thomas Gleixner [Wed, 25 Mar 2020 18:45:26 +0000 (19:45 +0100)]
x86/entry/64: Move non entry code into .text section
All ASM code which is not part of the entry functionality can move out into
the .text section. No reason to keep it in the non-instrumentable entry
section.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com> Acked-by: Peter Zijlstra <peterz@infradead.org> Link: https://lkml.kernel.org/r/20200505134340.227579223@linutronix.de
Thomas Gleixner [Tue, 10 Mar 2020 22:47:39 +0000 (23:47 +0100)]
lib/smp_processor_id: Move it into noinstr section
That code is already not traceable. Move it into the noinstr section so the
objtool section validation does not trigger.
Annotate the warning code as "safe". While it might be not under all
circumstances, getting the information out is important enough.
Should this ever trigger from the sensitive code which is shielded against
instrumentation, e.g. low level entry, then the printk is the least of the
worries.
Addresses the objtool warnings:
vmlinux.o: warning: objtool: context_tracking_recursion_enter()+0x7: call to __this_cpu_preempt_check() leaves .noinstr.text section
vmlinux.o: warning: objtool: __context_tracking_exit()+0x17: call to __this_cpu_preempt_check() leaves .noinstr.text section
vmlinux.o: warning: objtool: __context_tracking_enter()+0x2a: call to __this_cpu_preempt_check() leaves .noinstr.text section
Thomas Gleixner [Wed, 4 Mar 2020 10:05:22 +0000 (11:05 +0100)]
context_tracking: Ensure that the critical path cannot be instrumented
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
Peter Zijlstra [Thu, 20 Feb 2020 12:17:27 +0000 (13:17 +0100)]
x86/doublefault: Remove memmove() call
Use of memmove() in #DF is problematic considered tracing and other
instrumentation.
Remove the memmove() call and simply write out what needs doing; this
even clarifies the code, win-win! The code copies from the espfix64
stack to the normal task stack, there is no possible way for that to
overlap.
Andy Lutomirski [Mon, 24 Feb 2020 12:24:58 +0000 (13:24 +0100)]
x86/hw_breakpoint: Prevent data breakpoints on cpu_entry_area
A data breakpoint near the top of an IST stack will cause unrecoverable
recursion. A data breakpoint on the GDT, IDT, or TSS is terrifying.
Prevent either of these from happening.
Co-developed-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Borislav Petkov <bp@suse.de> Reviewed-by: Lai Jiangshan <jiangshanlai@gmail.com> Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com> Link: https://lkml.kernel.org/r/20200505134058.272448010@linutronix.de
x86/idt: Keep spurious entries unset in system_vectors
With commit dc20b2d52653 ("x86/idt: Move interrupt gate initialization to
IDT code") non assigned system vectors are also marked as used in
'used_vectors' (now 'system_vectors') bitmap. This makes checks in
arch_show_interrupts() whether a particular system vector is allocated to
always pass and e.g. 'Hyper-V reenlightenment interrupts' entry always
shows up in /proc/interrupts.
Another side effect of having all unassigned system vectors marked as used
is that irq_matrix_debug_show() will wrongly count them among 'System'
vectors.
As it is now ensured that alloc_intr_gate() is not called after init, it is
possible to leave unused entries in 'system_vectors' unset to fix these
issues.
There seems to be no reason to allocate interrupt gates after init. Mark
alloc_intr_gate() as __init and add WARN_ON() checks making sure it is
only used before idt_setup_apic_and_irq_gates() finalizes IDT setup and
maps all un-allocated entries to spurious entries.
x86/xen: Split HVM vector callback setup and interrupt gate allocation
As a preparatory change for making alloc_intr_gate() __init split
xen_callback_vector() into callback vector setup via hypercall
(xen_setup_callback_vector()) and interrupt gate allocation
(xen_alloc_callback_vector()).
xen_setup_callback_vector() is being called twice: on init and upon
system resume from xen_hvm_post_suspend(). alloc_intr_gate() only
needs to be called once.
Lai Jiangshan [Sun, 19 Apr 2020 14:40:49 +0000 (14:40 +0000)]
x86/entry/64: Remove an unused label
The label .Lcommon_\sym was introduced by 39e9543344fa.
(x86-64: Reduce amount of redundant code generated for invalidate_interruptNN)
And all the other relevant information was removed by 52aec3308db8
(x86/tlb: replace INVALIDATE_TLB_VECTOR by CALL_FUNCTION_VECTOR)
Ard Biesheuvel [Thu, 11 Jun 2020 12:43:30 +0000 (14:43 +0200)]
arm64: warn on incorrect placement of the kernel by the bootloader
Commit cfa7ede20f133c ("arm64: set TEXT_OFFSET to 0x0 in preparation for
removing it entirely") results in boot failures when booting kernels that
are built without KASLR support on broken bootloaders that ignore the
TEXT_OFFSET value passed via the header, and use the default of 0x80000
instead.
To work around this, turn CONFIG_RELOCATABLE on by default, even if KASLR
itself (CONFIG_RANDOMIZE_BASE) is turned off, and require CONFIG_EXPERT
to be enabled to deviate from this. Then, emit a warning into the kernel
log if we are not booting via the EFI stub (which is permitted to deviate
from the placement restrictions) and the kernel base address is not placed
according to the rules as laid out in Documentation/arm64/booting.rst.
Denis Efremov [Mon, 8 Jun 2020 09:59:44 +0000 (12:59 +0300)]
kbuild: fix broken builds because of GZIP,BZIP2,LZOP variables
Redefine GZIP, BZIP2, LZOP variables as KGZIP, KBZIP2, KLZOP resp.
GZIP, BZIP2, LZOP env variables are reserved by the tools. The original
attempt to redefine them internally doesn't work in makefiles/scripts
intercall scenarios, e.g., "make GZIP=gzip bindeb-pkg" and results in
broken builds. There can be other broken build commands because of this,
so the universal solution is to use non-reserved env variables for the
compression tools.
Masahiro Yamada [Sun, 7 Jun 2020 03:20:53 +0000 (12:20 +0900)]
samples: binderfs: really compile this sample and fix build issues
Even after commit c624adc9cb6e ("samples: fix binderfs sample"), this
sample is never compiled.
'hostprogs' teaches Kbuild that this is a host program, but not enough
to order to compile it. You must add it to 'always-y' to really compile
it.
Since this sample has never been compiled in upstream, various issues
are left unnoticed.
[1] compilers without <linux/android/binderfs.h> are still widely used
<linux/android/binderfs.h> is only available since commit c13295ad219d
("binderfs: rename header to binderfs.h"), i.e., Linux 5.0
If your compiler is based on UAPI headers older than Linux 5.0, you
will see the following error:
samples/binderfs/binderfs_example.c:16:10: fatal error: linux/android/binderfs.h: No such file or directory
#include <linux/android/binderfs.h>
^~~~~~~~~~~~~~~~~~~~~~~~~~
compilation terminated.
You cannot rely on compilers having such a new header.
The common approach is to install UAPI headers of this kernel into
usr/include, and then add it to the header search path.
I added 'depends on HEADERS_INSTALL' in Kconfig, and '-I usr/include'
compiler flag in Makefile.
[2] compile the sample for target architecture
Because headers_install works for the target architecture, only the
native compiler was able to build sample code that requires
'-I usr/include'.
Commit 7f3a59db274c ("kbuild: add infrastructure to build userspace
programs") added the new syntax 'userprogs' to compile user-space
programs for the target architecture.
Use it, and then 'ifndef CROSS_COMPILE' will go away.
I added 'depends on CC_CAN_LINK' because $(CC) is not necessarily
capable of linking user-space programs.
[3] use subdir-y to descend into samples/binderfs
Since this directory does not contain any kernel-space code, it has no
point in generating built-in.a or modules.order.
Replace obj-$(CONFIG_...) with subdir-$(CONFIG_...).
[4] -Wunused-variable warning
If I compile this, I see the following warning.
samples/binderfs/binderfs_example.c: In function 'main':
samples/binderfs/binderfs_example.c:21:9: warning: unused variable 'len' [-Wunused-variable]
21 | size_t len;
| ^~~
I removed the unused 'len'.
[5] CONFIG_ANDROID_BINDERFS is not required
Since this is a user-space standalone program, it is independent of
the kernel configuration.
Jean Delvare [Thu, 11 Jun 2020 10:03:47 +0000 (12:03 +0200)]
i2c: Drop stray comma in MODULE_AUTHOR statements
It is not the common usage to have a comma between the name and the
email address, so remove it.
Signed-off-by: Jean Delvare <jdelvare@suse.de> Cc: Kukjin Kim <kgene@kernel.org> Cc: Krzysztof Kozlowski <krzk@kernel.org> Reviewed-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
kernel test robot [Thu, 11 Jun 2020 02:50:35 +0000 (10:50 +0800)]
i2c: npcm7xx: npcm_i2caddr[] can be static
Fixes: f54736925a4f ("i2c: npcm7xx: Add support for slave mode for Nuvoton") Signed-off-by: kernel test robot <lkp@intel.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
Dave Airlie [Thu, 11 Jun 2020 07:51:06 +0000 (17:51 +1000)]
Merge tag 'drm-misc-next-fixes-2020-06-11' of git://anongit.freedesktop.org/drm/drm-misc into drm-next
In core, DRM connectors now notify userspace of hotplug events via
sysfs. In drivers, sun4i now uses 4 bits to store the clock's m divider;
ast sets up 24/32-bit color mode correctly.
Colin Ian King [Wed, 10 Jun 2020 11:58:04 +0000 (12:58 +0100)]
drm/ast: fix missing break in switch statement for format->cpp[0] case 4
Currently the switch statement for format->cpp[0] value 4 assigns
color_index which is never read again and then falls through to the
default case and returns. This looks like a missing break statement
bug. Fix this by adding a break statement.
Addresses-Coverity: ("Unused value") Fixes: 259d14a76a27 ("drm/ast: Split ast_set_vbios_mode_info()") Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> Tested-by: Thomas Zimmermann <tzimmermann@suse.de> Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de> Link: https://patchwork.freedesktop.org/patch/msgid/20200610115804.1132338-1-colin.king@canonical.com
Petr Mladek [Wed, 20 May 2020 10:22:33 +0000 (12:22 +0200)]
printk/kdb: Redirect printk messages into kdb in any context
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.
Peter Zijlstra [Fri, 24 Jan 2020 21:13:03 +0000 (22:13 +0100)]
locking/atomics: Flip fallbacks and instrumentation
Currently instrumentation of atomic primitives is done at the architecture
level, while composites or fallbacks are provided at the generic level.
The result is that there are no uninstrumented variants of the
fallbacks. Since there is now need of such variants to isolate text poke
from any form of instrumentation invert this ordering.
Doing this means moving the instrumentation into the generic code as
well as having (for now) two variants of the fallbacks.
Notes:
- the various *cond_read* primitives are not proper fallbacks
and got moved into linux/atomic.c. No arch_ variants are
generated because the base primitives smp_cond_load*()
are instrumented.
- once all architectures are moved over to arch_atomic_ one of the
fallback variants can be removed and some 2300 lines reclaimed.
- atomic_{read,set}*() are no longer double-instrumented
Reported-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Mark Rutland <mark.rutland@arm.com> Link: https://lkml.kernel.org/r/20200505134058.769149955@linutronix.de
Marco Elver [Tue, 26 Nov 2019 14:04:05 +0000 (15:04 +0100)]
asm-generic/atomic: Use __always_inline for fallback wrappers
Use __always_inline for atomic fallback wrappers. When building for size
(CC_OPTIMIZE_FOR_SIZE), some compilers appear to be less inclined to
inline even relatively small static inline functions that are assumed to
be inlinable such as atomic ops. This can cause problems, for example in
UACCESS regions.
While the fallback wrappers aren't pure wrappers, they are trivial
nonetheless, and the function they wrap should determine the final
inlining policy.
For x86 tinyconfig we observe:
- vmlinux baseline: 1315988
- vmlinux with patch: 1315928 (-60 bytes)
[ tglx: Cherry-picked from KCSAN ]
Suggested-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Marco Elver <elver@google.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Sivaprakash Murugesan [Mon, 8 Jun 2020 09:37:27 +0000 (15:07 +0530)]
mailbox: qcom: Add ipq6018 apcs compatible
The Qualcomm ipq6018 has apcs block, add compatible for the same. Also,
the ipq6018 apcs provides a clock functionality similar to msm8916 but
the clock driver is different.
Create a child device based on the apcs compatible for the clock
controller functionality.
Sivaprakash Murugesan [Mon, 8 Jun 2020 09:37:26 +0000 (15:07 +0530)]
mailbox: qcom: Add clock driver name in apcs mailbox driver data
Some apcs mailbox devices supports a clock driver, the compatible
strings of devices supporting clock driver along with the clock driver
name are maintained in a separate structure within the mailbox driver.
And the clock driver is added based on device match.
With increase in number of devices supporting the clock feature move the
clock driver name inside the driver data. so that we can use a single
API to get the register offset of mailbox driver and clock driver name
together, and the clock driver will be added based on the driver data.
Vincent Chen [Tue, 9 Jun 2020 14:14:49 +0000 (22:14 +0800)]
riscv: set the permission of vdso_data to read-only
The original vdso_data page is empty, so the permission of the vdso_data
page can be the same with the vdso text page. After introducing the vDSO
common flow, the vdso_data is not empty and the permission should be
changed to read-only.
Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Vincent Chen [Tue, 9 Jun 2020 14:14:48 +0000 (22:14 +0800)]
riscv: use vDSO common flow to reduce the latency of the time-related functions
Even if RISC-V has supported the vDSO feature, the latency of the functions
for obtaining the system time is still expensive. It is because these
functions still trigger a corresponding system call in the process, which
slows down the response time. If we want to remove the system call to
reduce the latency, the kernel should have the ability to output the system
clock information to userspace. This patch introduces the vDSO common flow
to enable the kernel to achieve the above feature and uses "rdtime"
instruction to obtain the current time in the user space. Under this
condition, the latency cost by the ecall from U-mode to S-mode can be
eliminated. After applying this patch, the latency of gettimeofday()
measured on the HiFive unleashed board can be reduced by %61.
Christoph Hellwig [Thu, 11 Jun 2020 01:42:10 +0000 (18:42 -0700)]
kernel: set USER_DS in kthread_use_mm
Some architectures like arm64 and s390 require USER_DS to be set for
kernel threads to access user address space, which is the whole purpose of
kthread_use_mm, but other like x86 don't. That has lead to a huge mess
where some callers are fixed up once they are tested on said
architectures, while others linger around and yet other like io_uring try
to do "clever" optimizations for what usually is just a trivial asignment
to a member in the thread_struct for most architectures.
Make kthread_use_mm set USER_DS, and kthread_unuse_mm restore to the
previous value instead.
Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Tested-by: Jens Axboe <axboe@kernel.dk> Reviewed-by: Jens Axboe <axboe@kernel.dk> Acked-by: Michael S. Tsirkin <mst@redhat.com> Cc: Alex Deucher <alexander.deucher@amd.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Felipe Balbi <balbi@kernel.org> Cc: Felix Kuehling <Felix.Kuehling@amd.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Zhenyu Wang <zhenyuw@linux.intel.com> Cc: Zhi Wang <zhi.a.wang@intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: http://lkml.kernel.org/r/20200404094101.672954-7-hch@lst.de Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Christoph Hellwig [Thu, 11 Jun 2020 01:42:06 +0000 (18:42 -0700)]
kernel: better document the use_mm/unuse_mm API contract
Switch the function documentation to kerneldoc comments, and add
WARN_ON_ONCE asserts that the calling thread is a kernel thread and does
not have ->mm set (or has ->mm set in the case of unuse_mm).
Also give the functions a kthread_ prefix to better document the use case.
[hch@lst.de: fix a comment typo, cover the newly merged use_mm/unuse_mm caller in vfio] Link: http://lkml.kernel.org/r/20200416053158.586887-3-hch@lst.de
[sfr@canb.auug.org.au: powerpc/vas: fix up for {un}use_mm() rename] Link: http://lkml.kernel.org/r/20200422163935.5aa93ba5@canb.auug.org.au Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Tested-by: Jens Axboe <axboe@kernel.dk> Reviewed-by: Jens Axboe <axboe@kernel.dk> Acked-by: Felix Kuehling <Felix.Kuehling@amd.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> [usb] Acked-by: Haren Myneni <haren@linux.ibm.com> Cc: Alex Deucher <alexander.deucher@amd.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Felipe Balbi <balbi@kernel.org> Cc: Jason Wang <jasowang@redhat.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Zhenyu Wang <zhenyuw@linux.intel.com> Cc: Zhi Wang <zhi.a.wang@intel.com> Link: http://lkml.kernel.org/r/20200404094101.672954-6-hch@lst.de Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Christoph Hellwig [Thu, 11 Jun 2020 01:42:03 +0000 (18:42 -0700)]
kernel: move use_mm/unuse_mm to kthread.c
cover the newly merged use_mm/unuse_mm caller in vfio
Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Felix Kuehling <Felix.Kuehling@amd.com> Cc: Alex Deucher <alexander.deucher@amd.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Felipe Balbi <balbi@kernel.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jason Wang <jasowang@redhat.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Zhenyu Wang <zhenyuw@linux.intel.com> Cc: Zhi Wang <zhi.a.wang@intel.com> Link: http://lkml.kernel.org/r/20200416053158.586887-2-hch@lst.de Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Christoph Hellwig [Thu, 11 Jun 2020 01:41:59 +0000 (18:41 -0700)]
kernel: move use_mm/unuse_mm to kthread.c
Patch series "improve use_mm / unuse_mm", v2.
This series improves the use_mm / unuse_mm interface by better documenting
the assumptions, and my taking the set_fs manipulations spread over the
callers into the core API.
This patch (of 3):
Use the proper API instead.
Link: http://lkml.kernel.org/r/20200404094101.672954-1-hch@lst.de
These helpers are only for use with kernel threads, and I will tie them
more into the kthread infrastructure going forward. Also move the
prototypes to kthread.h - mmu_context.h was a little weird to start with
as it otherwise contains very low-level MM bits.
Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Tested-by: Jens Axboe <axboe@kernel.dk> Reviewed-by: Jens Axboe <axboe@kernel.dk> Acked-by: Felix Kuehling <Felix.Kuehling@amd.com> Cc: Alex Deucher <alexander.deucher@amd.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Felipe Balbi <balbi@kernel.org> Cc: Jason Wang <jasowang@redhat.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Zhenyu Wang <zhenyuw@linux.intel.com> Cc: Zhi Wang <zhi.a.wang@intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: http://lkml.kernel.org/r/20200404094101.672954-1-hch@lst.de Link: http://lkml.kernel.org/r/20200416053158.586887-1-hch@lst.de Link: http://lkml.kernel.org/r/20200404094101.672954-5-hch@lst.de Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Walter Wu [Thu, 11 Jun 2020 01:41:56 +0000 (18:41 -0700)]
stacktrace: cleanup inconsistent variable type
Modify the variable type of 'skip' member of struct stack_trace.
In theory, the 'skip' variable type should be unsigned int.
There are two reasons:
- The 'skip' only has two situation, 1)Positive value, 2)Zero
- The 'skip' of struct stack_trace has inconsistent type with struct
stack_trace_data, it makes a bit confusion in the relationship between
struct stack_trace and stack_trace_data.
Signed-off-by: Walter Wu <walter-zh.wu@mediatek.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Cc: Matthias Brugger <matthias.bgg@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Link: http://lkml.kernel.org/r/20200421013511.5960-1-walter-zh.wu@mediatek.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ben Widawsky [Thu, 11 Jun 2020 01:41:50 +0000 (18:41 -0700)]
mm: add comments on pglist_data zones
While making other modifications it was easy to confuse the two struct
members node_zones and node_zonelists. For those already familiar with
the code, this might seem to be a silly patch, but it's quite helpful to
disambiguate the similar-sounding fields
While here, add a small comment on why nr_zones isn't simply MAX_NR_ZONES
Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Link: http://lkml.kernel.org/r/20200520205443.2757414-1-ben.widawsky@intel.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Keyur Patel [Thu, 11 Jun 2020 01:41:47 +0000 (18:41 -0700)]
ocfs2: fix spelling mistake and grammar
./ocfs2/mmap.c:65: bebongs ==> belonging
Signed-off-by: Keyur Patel <iamkeyur96@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com> Cc: Mark Fasheh <mark@fasheh.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Changwei Ge <gechangwei@live.cn> Cc: Gang He <ghe@suse.com> Cc: Jun Piao <piaojun@huawei.com> Link: http://lkml.kernel.org/r/20200608014818.102358-1-iamkeyur96@gmail.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mm/debug_vm_pgtable: fix kernel crash by checking for THP support
Architectures can have CONFIG_TRANSPARENT_HUGEPAGE enabled but no THP
support enabled based on platforms. For ex: with 4K PAGE_SIZE ppc64
supports THP only with radix translation.
This results in below crash when running with hash translation and 4K
PAGE_SIZE.
kernel BUG at arch/powerpc/include/asm/book3s/64/hash-4k.h:140!
cpu 0x61: Vector: 700 (Program Check) at [c000000ff948f860]
pc: debug_vm_pgtable+0x480/0x8b0
lr: debug_vm_pgtable+0x474/0x8b0
...
debug_vm_pgtable+0x374/0x8b0 (unreliable)
do_one_initcall+0x98/0x4f0
kernel_init_freeable+0x330/0x3fc
kernel_init+0x24/0x148
Alexander Gordeev [Thu, 11 Jun 2020 01:41:41 +0000 (18:41 -0700)]
lib: fix bitmap_parse() on 64-bit big endian archs
Commit 2d6261583be0 ("lib: rework bitmap_parse()") does not take into
account order of halfwords on 64-bit big endian architectures. As
result (at least) Receive Packet Steering, IRQ affinity masks and
runtime kernel test "test_bitmap" get broken on s390.
[andriy.shevchenko@linux.intel.com: convert infinite while loop to a for loop] Link: http://lkml.kernel.org/r/20200609140535.87160-1-andriy.shevchenko@linux.intel.com Fixes: 2d6261583be0 ("lib: rework bitmap_parse()") Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Cc: Yury Norov <yury.norov@gmail.com> Cc: Amritha Nambiar <amritha.nambiar@intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Kees Cook <keescook@chromium.org> Cc: Matthew Wilcox <willy@infradead.org> Cc: Miklos Szeredi <mszeredi@redhat.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Steffen Klassert <steffen.klassert@secunet.com> Cc: "Tobin C . Harding" <tobin@kernel.org> Cc: Vineet Gupta <vineet.gupta1@synopsys.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Willem de Bruijn <willemb@google.com> Cc: <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/1591634471-17647-1-git-send-email-agordeev@linux.ibm.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The list of kernel parameters has moved to a separate txt file, but
checkpatch has not been updated for this.
Make checkpatch.pl look for the documentation for new kernel parameters
in kernel-parameters.txt instead of kernel-parameters.rst.
Fixes: e52347bd66f6 ("Documentation/admin-guide: split the kernel parameter list to a separate file") Signed-off-by: Tim Froidcoeur <tim.froidcoeur@tessares.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Joe Perches <joe@perches.com> Cc: Mauro Carvalho Chehab <mchehab@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ryusuke Konishi [Thu, 11 Jun 2020 01:41:35 +0000 (18:41 -0700)]
nilfs2: fix null pointer dereference at nilfs_segctor_do_construct()
After commit c3aab9a0bd91 ("mm/filemap.c: don't initiate writeback if
mapping has no dirty pages"), the following null pointer dereference has
been reported on nilfs2:
This crash turned out to be caused by set_page_writeback() call for
segment summary buffers at nilfs_segctor_prepare_write().
set_page_writeback() can call inc_wb_stat(inode_to_wb(inode),
WB_WRITEBACK) where inode_to_wb(inode) is NULL if the inode of
underlying block device does not have an associated wb.
This fixes the issue by calling inode_attach_wb() in advance to ensure
to associate the bdev inode with its wb.
Fixes: c3aab9a0bd91 ("mm/filemap.c: don't initiate writeback if mapping has no dirty pages") Reported-by: Walton Hoops <me@waltonhoops.com> Reported-by: Tomas Hlavaty <tom@logand.com> Reported-by: ARAI Shun-ichi <hermes@ceres.dti.ne.jp> Reported-by: Hideki EIRAKU <hdk1983@gmail.com> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Cc: <stable@vger.kernel.org> [5.4+] Link: http://lkml.kernel.org/r/20200608.011819.1399059588922299158.konishi.ryusuke@gmail.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Andrey Konovalov [Thu, 11 Jun 2020 01:41:28 +0000 (18:41 -0700)]
kcov: check kcov_softirq in kcov_remote_stop()
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: 5ff3b30ab57d ("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>
Dan Carpenter [Thu, 11 Jun 2020 01:41:22 +0000 (18:41 -0700)]
khugepaged: selftests: fix timeout condition in wait_for_scan()
The loop exits with "timeout" set to -1 and not to 0 so the test needs to
be fixed.
Fixes: e7b592f6caca ("khugepaged: add self test") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Shuah Khan <shuah@kernel.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Zi Yan <ziy@nvidia.com> Cc: William Kucharski <william.kucharski@oracle.com> Cc: Yang Shi <yang.shi@linux.alibaba.com> Cc: John Hubbard <jhubbard@nvidia.com> Link: http://lkml.kernel.org/r/20200605110736.GH978434@mwanda Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Tom Rix [Wed, 10 Jun 2020 21:57:13 +0000 (14:57 -0700)]
selinux: fix double free
Clang's static analysis tool reports these double free memory errors.
security/selinux/ss/services.c:2987:4: warning: Attempt to free released memory [unix.Malloc]
kfree(bnames[i]);
^~~~~~~~~~~~~~~~
security/selinux/ss/services.c:2990:2: warning: Attempt to free released memory [unix.Malloc]
kfree(bvalues);
^~~~~~~~~~~~~~
So improve the security_get_bools error handling by freeing these variables
and setting their return pointers to NULL and the return len to 0
Cc: stable@vger.kernel.org Signed-off-by: Tom Rix <trix@redhat.com> Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
Linus Torvalds [Thu, 11 Jun 2020 01:09:13 +0000 (18:09 -0700)]
Merge branch 'work.epoll' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull epoll update from Al Viro:
"epoll conversion to read_iter from Jens; I thought there might be more
epoll stuff this cycle, but uaccess took too much time"
* 'work.epoll' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
eventfd: convert to f_op->read_iter()
Jakub Kicinski [Wed, 10 Jun 2020 23:59:11 +0000 (16:59 -0700)]
docs: networkng: convert sja1105's devlink info to RTS
A new file snuck into the tree after all existing documentation
was converted to RST. Convert sja1105's devlink info and move
it where the rest of the drivers are documented.
Signed-off-by: Jakub Kicinski <kuba@kernel.org> Acked-by: Vladimir Oltean <vladimir.oltean@nxp.com> Tested-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Xiaoguang Wang [Wed, 10 Jun 2020 11:41:20 +0000 (19:41 +0800)]
io_uring: avoid unnecessary io_wq_work copy for fast poll feature
Basically IORING_OP_POLL_ADD command and async armed poll handlers
for regular commands don't touch io_wq_work, so only REQ_F_WORK_INITIALIZED
is set, can we do io_wq_work copy and restore.
Signed-off-by: Xiaoguang Wang <xiaoguang.wang@linux.alibaba.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
Xiaoguang Wang [Wed, 10 Jun 2020 11:41:19 +0000 (19:41 +0800)]
io_uring: avoid whole io_wq_work copy for requests completed inline
If requests can be submitted and completed inline, we don't need to
initialize whole io_wq_work in io_init_req(), which is an expensive
operation, add a new 'REQ_F_WORK_INITIALIZED' to determine whether
io_wq_work is initialized and add a helper io_req_init_async(), users
must call io_req_init_async() for the first time touching any members
of io_wq_work.
I use /dev/nullb0 to evaluate performance improvement in my physical
machine:
modprobe null_blk nr_devices=1 completion_nsec=0
sudo taskset -c 60 fio -name=fiotest -filename=/dev/nullb0 -iodepth=128
-thread -rw=read -ioengine=io_uring -direct=1 -bs=4k -size=100G -numjobs=1
-time_based -runtime=120
before this patch:
Run status group 0 (all jobs):
READ: bw=724MiB/s (759MB/s), 724MiB/s-724MiB/s (759MB/s-759MB/s),
io=84.8GiB (91.1GB), run=120001-120001msec
With this patch:
Run status group 0 (all jobs):
READ: bw=761MiB/s (798MB/s), 761MiB/s-761MiB/s (798MB/s-798MB/s),
io=89.2GiB (95.8GB), run=120001-120001msec
About 5% improvement.
Signed-off-by: Xiaoguang Wang <xiaoguang.wang@linux.alibaba.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
Jakub Kicinski [Wed, 10 Jun 2020 23:09:06 +0000 (16:09 -0700)]
docs: networkng: fix lists and table in sja1105
We need an empty line before list stats, otherwise first point
will be smooshed into the paragraph. Inside tables text must
start at the same offset in the cell, otherwise sphinx thinks
it's a new indented block.
Documentation/networking/dsa/sja1105.rst:108: WARNING: Block quote ends without a blank line; unexpected unindent.
Documentation/networking/dsa/sja1105.rst:112: WARNING: Definition list ends without a blank line; unexpected unindent.
Documentation/networking/dsa/sja1105.rst:245: WARNING: Unexpected indentation.
Documentation/networking/dsa/sja1105.rst:246: WARNING: Block quote ends without a blank line; unexpected unindent.
Documentation/networking/dsa/sja1105.rst:253: WARNING: Unexpected indentation.
Documentation/networking/dsa/sja1105.rst:254: WARNING: Block quote ends without a blank line; unexpected unindent.
Fixes: a20bc43bfb2e ("docs: net: dsa: sja1105: document the best_effort_vlan_filtering option") Signed-off-by: Jakub Kicinski <kuba@kernel.org> Acked-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>