Commit Graph

7245 Commits

Author SHA1 Message Date
Thomas Gleixner
588787fde7 x86/idt: Move early IDT handler setup to IDT code
The early IDT handler setup is done in C entry code on 64-bit kernels and in
ASM entry code on 32-bit kernels.

Move the 64-bit variant to the IDT code so it can be shared with 32-bit
in the next step.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20170828064958.679561404@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-29 12:07:26 +02:00
Thomas Gleixner
e802a51ede x86/idt: Consolidate IDT invalidation
kexec and reboot have both code to invalidate IDT. Create a common function
and use it.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20170828064958.600953282@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-29 12:07:26 +02:00
Thomas Gleixner
8f55868f9e x86/idt: Remove unused set_trap_gate()
This inline is not used at all.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20170828064958.522053134@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-29 12:07:26 +02:00
Thomas Gleixner
87cc037674 x86/ldttss: Clean up 32-bit descriptors
Like the IDT descriptors, the LDT/TSS descriptors are pointlessly different
on 32 and 64 bit kernels.

Unify them and get rid of the duplicated code.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20170828064958.289634692@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-29 12:07:25 +02:00
Thomas Gleixner
38e9e81f4c x86/gdt: Use bitfields for initialization
The GDT entry related code uses two ways to access entries via
union fields:

 - bitfields

 - macros which initialize the two 16-bit parts of the entry
   by magic shift and mask operations.

Clean it up and only use the bitfields to initialize and access entries.

( The old access patterns were partly done due to GCC optimizing bitfield
  accesses in a horrible way - that's mostly fixed these days and clarity
  of code in such low level accessors is very important. )

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20170828064958.197673367@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-29 12:07:25 +02:00
Thomas Gleixner
9a98e77800 x86/asm: Replace access to desc_struct:a/b fields
The union inside of desc_struct which allows access to the raw u32 parts of
the descriptors. This raw access part is about to go away.

Replace the few code parts which access those fields.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20170828064958.120214366@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-29 12:07:25 +02:00
Thomas Gleixner
64b163fab6 x86/idt: Unify gate_struct handling for 32/64-bit kernels
The first 32 bits of gate struct are the same for 32 and 64 bit kernels.

The 32-bit version uses desc_struct and no designated data structure,
so we need different accessors for 32 and 64 bit kernels.

Aside of that the macros which are necessary to build the 32-bit
gate descriptor are horrible to read.

Unify the gate structs and switch all code fiddling with it over.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20170828064957.861974317@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-29 12:07:24 +02:00
Thomas Gleixner
7328552780 x86/tracing: Build tracepoints only when they are used
The tracepoint macro magic emits code for all tracepoints in a event header
file. That code stays around even if the tracepoint is not used at all. The
linker does not discard it.

Build the various irq_vector tracepoints dependent on the appropriate CONFIG
switches.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20170828064957.770651777@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-29 12:07:24 +02:00
Thomas Gleixner
a45525b5b4 x86/irq_work: Make it depend on APIC
The irq work interrupt vector is only installed when CONFIG_X86_LOCAL_APIC is
enabled, but the interrupt handler is compiled in unconditionally.

Compile the cruft out when the APIC is disabled.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20170828064957.691909010@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-29 11:42:30 +02:00
Thomas Gleixner
0428e01a2f x86/ipi: Make platform IPI depend on APIC
The platform IPI vector is only installed when the local APIC is enabled. All
users of it depend on the local APIC anyway.

Make the related code conditional on CONFIG_X86_LOCAL_APIC=y.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20170828064957.615286163@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-29 11:42:29 +02:00
Thomas Gleixner
809547472e x86/tracing: Disentangle pagefault and resched IPI tracing key
The pagefault and the resched IPI handler are the only ones where it is
worth to optimize the code further in case tracepoints are disabled. But it
makes no sense to have a single static key for both.

Seperate the static keys so the facilities are handled seperately.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20170828064957.536699116@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-29 11:42:29 +02:00
Thomas Gleixner
6f54f3ec6c x86/idt: Clean up the i386 low level entry macros
Some of the entry function defines for i386 were explictely using the
BUILD_INTERRUPT3() macro to prevent that the extra trace entry got added
via BUILD_INTERRUPT(). No that the trace cruft is gone, the file can be
cleaned up and converted to use BUILD_INTERRUPT() which avoids the ugly
line breaks.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20170828064957.456815006@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-29 11:42:28 +02:00
Thomas Gleixner
4b9a8dca0e x86/idt: Remove the tracing IDT completely
No more users of the tracing IDT. All exception tracepoints have been moved
into the regular handlers. Get rid of the mess which shouldn't have been
created in the first place.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20170828064957.378851687@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-29 11:42:28 +02:00
Thomas Gleixner
3cd788c1ee x86/smp: Use static key for reschedule interrupt tracing
It's worth to avoid the extra irq_enter()/irq_exit() pair in the case that
the reschedule interrupt tracepoints are disabled.

Use the static key which indicates that exception tracing is enabled. For
now this key is global. It will be optimized in a later step.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170828064957.299808677@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-29 11:42:27 +02:00
Thomas Gleixner
85b77cdd8f x86/smp: Remove pointless duplicated interrupt code
Two NOP5s are really a good tradeoff vs. the unholy IDT switching mess,
which duplicates code all over the place. The rescheduling interrupt gets
optimized in a later step.

Make the ordering of function call and statistics increment the same as in
other places. Calculate stats first, then do the function call.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20170828064957.222101344@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-29 11:42:27 +02:00
Thomas Gleixner
0f42ae283c x86/mce: Remove duplicated tracing interrupt code
Machine checks are not really high frequency events. The extra two NOP5s for
the disabled tracepoints are noise vs. the heavy lifting which needs to be
done in the MCE handler.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20170828064957.144301907@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-29 11:42:26 +02:00
Thomas Gleixner
daabb8eb9a x86/irqwork: Get rid of duplicated tracing interrupt code
Two NOP5s are a reasonable tradeoff to avoid duplicated code and the
requirement to switch the IDT.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20170828064957.064746737@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-29 11:42:26 +02:00
Thomas Gleixner
61069de7a3 x86/apic: Remove the duplicated tracing versions of interrupts
The error and the spurious interrupt are really rare events and not at all
performance sensitive: two NOP5s can be tolerated when tracing is disabled.

Remove the complication.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170828064956.986009402@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-29 11:42:25 +02:00
Thomas Gleixner
8a17116b1f x86/irq: Get rid of duplicated trace_x86_platform_ipi() code
Two NOP5s are really a good tradeoff vs. the unholy IDT switching mess,
which duplicates code all over the place.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170828064956.907209383@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-29 11:42:25 +02:00
Thomas Gleixner
302a98f896 x86/apic: Remove the duplicated tracing version of local_timer_interrupt()
The two NOP5s are noise in the rest of the work which is done by the timer
interrupt and modern CPUs are pretty good in optimizing NOPs anyway.

Get rid of the interrupt handler duplication and move the tracepoints into
the regular handler.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170828064956.751247330@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-29 11:42:24 +02:00
Thomas Gleixner
11a7ffb017 x86/traps: Simplify pagefault tracing logic
Make use of the new irqvector tracing static key and remove the duplicated
trace_do_pagefault() implementation.

If irq vector tracing is disabled, then the overhead of this is a single
NOP5, which is a reasonable tradeoff to avoid duplicated code and the
unholy macro mess.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20170828064956.672965407@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-29 11:42:23 +02:00
Thomas Gleixner
2feb1b316d x86/tracing: Introduce a static key for exception tracing
Switching the IDT just for avoiding tracepoints creates a completely
impenetrable macro/inline/ifdef mess.

There is no point in avoiding tracepoints for most of the traps/exceptions.
For the more expensive tracepoints, like pagefaults, this can be handled with
an explicit static key.

Preparatory patch to remove the tracing IDT.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20170828064956.593094539@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-29 11:42:23 +02:00
Thomas Gleixner
9aec458ff0 x86/irq: Remove duplicated used_vectors definition
Also remove the unparseable comment in the other place while at it.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20170828064956.436711634@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-29 11:42:21 +02:00
Thomas Gleixner
05161b9cbe x86/irq: Get rid of the 'first_system_vector' indirection bogosity
This variable is beyond pointless. Nothing allocates a vector via
alloc_gate() below FIRST_SYSTEM_VECTOR. So nothing can change
first_system_vector.

If there is a need for a gate below FIRST_SYSTEM_VECTOR then it can be
added to the vector defines and FIRST_SYSTEM_VECTOR can be adjusted
accordingly.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20170828064956.357109735@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-29 11:42:21 +02:00
Thomas Gleixner
69de72ec6d x86/irq: Remove vector_used_by_percpu_irq()
Last user (lguest) is gone. Remove it.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20170828064956.201432430@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-29 11:42:20 +02:00
Ingo Molnar
416b0c0faf Merge branch 'linus' into x86/apic, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-29 11:42:07 +02:00
Linus Torvalds
c153e62105 Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Ingo Molnar:
 "Two fixes: one for an ldt_struct handling bug and a cherry-picked
  objtool fix"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm: Fix use-after-free of ldt_struct
  objtool: Fix '-mtune=atom' decoding support in objtool 2.0
2017-08-26 09:06:28 -07:00
Eric Biggers
ccd5b32351 x86/mm: Fix use-after-free of ldt_struct
The following commit:

  39a0526fb3 ("x86/mm: Factor out LDT init from context init")

renamed init_new_context() to init_new_context_ldt() and added a new
init_new_context() which calls init_new_context_ldt().  However, the
error code of init_new_context_ldt() was ignored.  Consequently, if a
memory allocation in alloc_ldt_struct() failed during a fork(), the
->context.ldt of the new task remained the same as that of the old task
(due to the memcpy() in dup_mm()).  ldt_struct's are not intended to be
shared, so a use-after-free occurred after one task exited.

Fix the bug by making init_new_context() pass through the error code of
init_new_context_ldt().

This bug was found by syzkaller, which encountered the following splat:

    BUG: KASAN: use-after-free in free_ldt_struct.part.2+0x10a/0x150 arch/x86/kernel/ldt.c:116
    Read of size 4 at addr ffff88006d2cb7c8 by task kworker/u9:0/3710

    CPU: 1 PID: 3710 Comm: kworker/u9:0 Not tainted 4.13.0-rc4-next-20170811 #2
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
    Call Trace:
     __dump_stack lib/dump_stack.c:16 [inline]
     dump_stack+0x194/0x257 lib/dump_stack.c:52
     print_address_description+0x73/0x250 mm/kasan/report.c:252
     kasan_report_error mm/kasan/report.c:351 [inline]
     kasan_report+0x24e/0x340 mm/kasan/report.c:409
     __asan_report_load4_noabort+0x14/0x20 mm/kasan/report.c:429
     free_ldt_struct.part.2+0x10a/0x150 arch/x86/kernel/ldt.c:116
     free_ldt_struct arch/x86/kernel/ldt.c:173 [inline]
     destroy_context_ldt+0x60/0x80 arch/x86/kernel/ldt.c:171
     destroy_context arch/x86/include/asm/mmu_context.h:157 [inline]
     __mmdrop+0xe9/0x530 kernel/fork.c:889
     mmdrop include/linux/sched/mm.h:42 [inline]
     exec_mmap fs/exec.c:1061 [inline]
     flush_old_exec+0x173c/0x1ff0 fs/exec.c:1291
     load_elf_binary+0x81f/0x4ba0 fs/binfmt_elf.c:855
     search_binary_handler+0x142/0x6b0 fs/exec.c:1652
     exec_binprm fs/exec.c:1694 [inline]
     do_execveat_common.isra.33+0x1746/0x22e0 fs/exec.c:1816
     do_execve+0x31/0x40 fs/exec.c:1860
     call_usermodehelper_exec_async+0x457/0x8f0 kernel/umh.c:100
     ret_from_fork+0x2a/0x40 arch/x86/entry/entry_64.S:431

    Allocated by task 3700:
     save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59
     save_stack+0x43/0xd0 mm/kasan/kasan.c:447
     set_track mm/kasan/kasan.c:459 [inline]
     kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:551
     kmem_cache_alloc_trace+0x136/0x750 mm/slab.c:3627
     kmalloc include/linux/slab.h:493 [inline]
     alloc_ldt_struct+0x52/0x140 arch/x86/kernel/ldt.c:67
     write_ldt+0x7b7/0xab0 arch/x86/kernel/ldt.c:277
     sys_modify_ldt+0x1ef/0x240 arch/x86/kernel/ldt.c:307
     entry_SYSCALL_64_fastpath+0x1f/0xbe

    Freed by task 3700:
     save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59
     save_stack+0x43/0xd0 mm/kasan/kasan.c:447
     set_track mm/kasan/kasan.c:459 [inline]
     kasan_slab_free+0x71/0xc0 mm/kasan/kasan.c:524
     __cache_free mm/slab.c:3503 [inline]
     kfree+0xca/0x250 mm/slab.c:3820
     free_ldt_struct.part.2+0xdd/0x150 arch/x86/kernel/ldt.c:121
     free_ldt_struct arch/x86/kernel/ldt.c:173 [inline]
     destroy_context_ldt+0x60/0x80 arch/x86/kernel/ldt.c:171
     destroy_context arch/x86/include/asm/mmu_context.h:157 [inline]
     __mmdrop+0xe9/0x530 kernel/fork.c:889
     mmdrop include/linux/sched/mm.h:42 [inline]
     __mmput kernel/fork.c:916 [inline]
     mmput+0x541/0x6e0 kernel/fork.c:927
     copy_process.part.36+0x22e1/0x4af0 kernel/fork.c:1931
     copy_process kernel/fork.c:1546 [inline]
     _do_fork+0x1ef/0xfb0 kernel/fork.c:2025
     SYSC_clone kernel/fork.c:2135 [inline]
     SyS_clone+0x37/0x50 kernel/fork.c:2129
     do_syscall_64+0x26c/0x8c0 arch/x86/entry/common.c:287
     return_from_SYSCALL_64+0x0/0x7a

Here is a C reproducer:

    #include <asm/ldt.h>
    #include <pthread.h>
    #include <signal.h>
    #include <stdlib.h>
    #include <sys/syscall.h>
    #include <sys/wait.h>
    #include <unistd.h>

    static void *fork_thread(void *_arg)
    {
        fork();
    }

    int main(void)
    {
        struct user_desc desc = { .entry_number = 8191 };

        syscall(__NR_modify_ldt, 1, &desc, sizeof(desc));

        for (;;) {
            if (fork() == 0) {
                pthread_t t;

                srand(getpid());
                pthread_create(&t, NULL, fork_thread, NULL);
                usleep(rand() % 10000);
                syscall(__NR_exit_group, 0);
            }
            wait(NULL);
        }
    }

Note: the reproducer takes advantage of the fact that alloc_ldt_struct()
may use vmalloc() to allocate a large ->entries array, and after
commit:

  5d17a73a2e ("vmalloc: back off when the current task is killed")

it is possible for userspace to fail a task's vmalloc() by
sending a fatal signal, e.g. via exit_group().  It would be more
difficult to reproduce this bug on kernels without that commit.

This bug only affected kernels with CONFIG_MODIFY_LDT_SYSCALL=y.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: <stable@vger.kernel.org> [v4.6+]
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Fixes: 39a0526fb3 ("x86/mm: Factor out LDT init from context init")
Link: http://lkml.kernel.org/r/20170824175029.76040-1-ebiggers3@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-25 09:55:52 +02:00
Paolo Bonzini
38cfd5e3df KVM, pkeys: do not use PKRU value in vcpu->arch.guest_fpu.state
The host pkru is restored right after vcpu exit (commit 1be0e61), so
KVM_GET_XSAVE will return the host PKRU value instead.  Fix this by
using the guest PKRU explicitly in fill_xsave and load_xsave.  This
part is based on a patch by Junkang Fu.

The host PKRU data may also not match the value in vcpu->arch.guest_fpu.state,
because it could have been changed by userspace since the last time
it was saved, so skip loading it in kvm_load_guest_fpu.

Reported-by: Junkang Fu <junkang.fjk@alibaba-inc.com>
Cc: Yang Zhang <zy107165@alibaba-inc.com>
Fixes: 1be0e61c1f
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-08-25 09:28:37 +02:00
Paolo Bonzini
b9dd21e104 KVM: x86: simplify handling of PKRU
Move it to struct kvm_arch_vcpu, replacing guest_pkru_valid with a
simple comparison against the host value of the register.  The write of
PKRU in addition can be skipped if the guest has not enabled the feature.
Once we do this, we need not test OSPKE in the host anymore, because
guest_CR4.PKE=1 implies host_CR4.PKE=1.

The static PKU test is kept to elide the code on older CPUs.

Suggested-by: Yang Zhang <zy107165@alibaba-inc.com>
Fixes: 1be0e61c1f
Cc: stable@vger.kernel.org
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-08-25 09:28:28 +02:00
Thomas Gleixner
c0bb80cfa3 Merge branch 'x86/asm' into x86/apic
Pick up dependent changes to avoid merge conflicts
2017-08-25 08:56:22 +02:00
Juergen Gross
ecda85e702 x86/lguest: Remove lguest support
Lguest seems to be rather unused these days. It has seen only patches
ensuring it still builds the last two years and its official state is
"Odd Fixes".

Remove it in order to be able to clean up the paravirt code.

Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: boris.ostrovsky@oracle.com
Cc: lguest@lists.ozlabs.org
Cc: rusty@rustcorp.com.au
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/20170816173157.8633-3-jgross@suse.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-24 09:57:28 +02:00
Linus Torvalds
7f680d7ec3 Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Thomas Gleixner:
 "Another pile of small fixes and updates for x86:

   - Plug a hole in the SMAP implementation which misses to clear AC on
     NMI entry

   - Fix the norandmaps/ADDR_NO_RANDOMIZE logic so the command line
     parameter works correctly again

   - Use the proper accessor in the startup64 code for next_early_pgt to
     prevent accessing of invalid addresses and faulting in the early
     boot code.

   - Prevent CPU hotplug lock recursion in the MTRR code

   - Unbreak CPU0 hotplugging

   - Rename overly long CPUID bits which got introduced in this cycle

   - Two commits which mark data 'const' and restrict the scope of data
     and functions to file scope by making them 'static'"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86: Constify attribute_group structures
  x86/boot/64/clang: Use fixup_pointer() to access 'next_early_pgt'
  x86/elf: Remove the unnecessary ADDR_NO_RANDOMIZE checks
  x86: Fix norandmaps/ADDR_NO_RANDOMIZE
  x86/mtrr: Prevent CPU hotplug lock recursion
  x86: Mark various structures and functions as 'static'
  x86/cpufeature, kvm/svm: Rename (shorten) the new "virtualized VMSAVE/VMLOAD" CPUID flag
  x86/smpboot: Unbreak CPU0 hotplug
  x86/asm/64: Clear AC on NMI entries
2017-08-20 09:36:52 -07:00
Kees Cook
c715b72c1b mm: revert x86_64 and arm64 ELF_ET_DYN_BASE base changes
Moving the x86_64 and arm64 PIE base from 0x555555554000 to 0x000100000000
broke AddressSanitizer.  This is a partial revert of:

  eab09532d4 ("binfmt_elf: use ELF_ET_DYN_BASE only for PIE")
  02445990a9 ("arm64: move ELF_ET_DYN_BASE to 4GB / 4MB")

The AddressSanitizer tool has hard-coded expectations about where
executable mappings are loaded.

The motivation for changing the PIE base in the above commits was to
avoid the Stack-Clash CVEs that allowed executable mappings to get too
close to heap and stack.  This was mainly a problem on 32-bit, but the
64-bit bases were moved too, in an effort to proactively protect those
systems (proofs of concept do exist that show 64-bit collisions, but
other recent changes to fix stack accounting and setuid behaviors will
minimize the impact).

The new 32-bit PIE base is fine for ASan (since it matches the ET_EXEC
base), so only the 64-bit PIE base needs to be reverted to let x86 and
arm64 ASan binaries run again.  Future changes to the 64-bit PIE base on
these architectures can be made optional once a more dynamic method for
dealing with AddressSanitizer is found.  (e.g.  always loading PIE into
the mmap region for marked binaries.)

Link: http://lkml.kernel.org/r/20170807201542.GA21271@beast
Fixes: eab09532d4 ("binfmt_elf: use ELF_ET_DYN_BASE only for PIE")
Fixes: 02445990a9 ("arm64: move ELF_ET_DYN_BASE to 4GB / 4MB")
Signed-off-by: Kees Cook <keescook@chromium.org>
Reported-by: Kostya Serebryany <kcc@google.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-08-18 15:32:02 -07:00
Linus Torvalds
043cd07c55 xen: Fixes for 4.13-rc5
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Merge tag 'for-linus-4.13b-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen fixes from Juergen Gross:
 "Some fixes for Xen:

   - a fix for a regression introduced in 4.13 for a Xen HVM-guest
     configured with KASLR

   - a fix for a possible deadlock in the xenbus driver when booting the
     system

   - a fix for lost interrupts in Xen guests"

* tag 'for-linus-4.13b-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen/events: Fix interrupt lost during irq_disable and irq_enable
  xen: avoid deadlock in xenbus
  xen: fix hvm guest with kaslr enabled
  xen: split up xen_hvm_init_shared_info()
  x86: provide an init_mem_mapping hypervisor hook
2017-08-12 09:01:36 -07:00
Juergen Gross
c138d81163 x86: provide an init_mem_mapping hypervisor hook
Provide a hook in hypervisor_x86 called after setting up initial
memory mapping.

This is needed e.g. by Xen HVM guests to map the hypervisor shared
info page.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Juergen Gross <jgross@suse.com>
2017-08-11 15:50:21 +02:00
Borislav Petkov
5442c26995 x86/cpufeature, kvm/svm: Rename (shorten) the new "virtualized VMSAVE/VMLOAD" CPUID flag
"virtual_vmload_vmsave" is what is going to land in /proc/cpuinfo now
as per v4.13-rc4, for a single feature bit which is clearly too long.

So rename it to what it is called in the processor manual.
"v_vmsave_vmload" is a bit shorter, after all.

We could go more aggressively here but having it the same as in the
processor manual is advantageous.

Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Radim Krčmář <rkrcmar@redhat.com>
Cc: Janakarajan Natarajan <Janakarajan.Natarajan@amd.com>
Cc: Jörg Rödel <joro@8bytes.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kvm-ML <kvm@vger.kernel.org>
Link: http://lkml.kernel.org/r/20170801185552.GA3743@nazgul.tnic
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-11 13:42:28 +02:00
Andy Lutomirski
9584d98bed x86/fsgsbase/64: Report FSBASE and GSBASE correctly in core dumps
In ELF_COPY_CORE_REGS, we're copying from the current task, so
accessing thread.fsbase and thread.gsbase makes no sense.  Just read
the values from the CPU registers.

In practice, the old code would have been correct most of the time
simply because thread.fsbase and thread.gsbase usually matched the
CPU registers.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Chang Seok <chang.seok.bae@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-10 17:15:13 +02:00
Josh Poimboeuf
af79ded44b x86/asm: Fix UNWIND_HINT_REGS macro for older binutils
Apparently the binutils 2.20 assembler can't handle the '&&' operator in
the UNWIND_HINT_REGS macro.  Rearrange the macro to do without it.

This fixes the following error:

  arch/x86/entry/entry_64.S: Assembler messages:
  arch/x86/entry/entry_64.S:521: Error: non-constant expression in ".if" statement
  arch/x86/entry/entry_64.S:521: Error: non-constant expression in ".if" statement
  arch/x86/entry/entry_64.S:521: Error: non-constant expression in ".if" statement
  arch/x86/entry/entry_64.S:521: Error: non-constant expression in ".if" statement
  arch/x86/entry/entry_64.S:521: Error: non-constant expression in ".if" statement
  arch/x86/entry/entry_64.S:521: Error: non-constant expression in ".if" statement
  arch/x86/entry/entry_64.S:521: Error: non-constant expression in ".if" statement
  arch/x86/entry/entry_64.S:521: Error: non-constant expression in ".if" statement
  arch/x86/entry/entry_64.S:521: Error: non-constant expression in ".if" statement

Reported-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 39358a033b ("objtool, x86: Add facility for asm code to provide unwind hints")
Link: http://lkml.kernel.org/r/e2ad97c1ae49a484644b4aaa4dd3faa4d6d969b2.1502116651.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-10 14:16:19 +02:00
Andy Lutomirski
603e492e86 x86/asm/32: Fix regs_get_register() on segment registers
The segment register high words on x86_32 may contain garbage.
Teach regs_get_register() to read them as u16 instead of unsigned
long.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/0b76f6dbe477b7b1a81938fddcc3c483d48f0ff2.1502314765.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-10 13:14:58 +02:00
Ingo Molnar
1d0f49e140 Merge branch 'x86/urgent' into x86/asm, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-10 13:14:15 +02:00
Andy Lutomirski
99504819fc x86/asm/32: Remove a bunch of '& 0xffff' from pt_regs segment reads
Now that pt_regs properly defines segment fields as 16-bit on 32-bit
CPUs, there's no need to mask off the high word.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-07-30 12:04:41 +02:00
Andy Lutomirski
385eca8f27 x86/asm/32: Make pt_regs's segment registers be 16 bits
Many 32-bit x86 CPUs do 16-bit writes when storing segment registers to
memory.  This can cause the high word of regs->[cdefgs]s to
occasionally contain garbage.

Rather than making the entry code more complicated to fix up the
garbage, just change pt_regs to reflect reality.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-07-30 12:04:40 +02:00
Wincy Van
210f84b0ca x86: irq: Define a global vector for nested posted interrupts
We are using the same vector for nested/non-nested posted
interrupts delivery, this may cause interrupts latency in
L1 since we can't kick the L2 vcpu out of vmx-nonroot mode.

This patch introduces a new vector which is only for nested
posted interrupts to solve the problems above.

Signed-off-by: Wincy Van <fanwenyi0529@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-07-26 18:57:45 +02:00
Josh Poimboeuf
81d3871900 x86/kconfig: Consolidate unwinders into multiple choice selection
There are three mutually exclusive unwinders.  Make that more obvious by
combining them into a multiple-choice selection:

  CONFIG_FRAME_POINTER_UNWINDER
  CONFIG_ORC_UNWINDER
  CONFIG_GUESS_UNWINDER (if CONFIG_EXPERT=y)

Frame pointers are still the default (for now).

The old CONFIG_FRAME_POINTER option is still used in some
arch-independent places, so keep it around, but make it
invisible to the user on x86 - it's now selected by
CONFIG_FRAME_POINTER_UNWINDER=y.

Suggested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/20170725135424.zukjmgpz3plf5pmt@treble
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-07-26 14:05:36 +02:00
Josh Poimboeuf
ee9f8fce99 x86/unwind: Add the ORC unwinder
Add the new ORC unwinder which is enabled by CONFIG_ORC_UNWINDER=y.
It plugs into the existing x86 unwinder framework.

It relies on objtool to generate the needed .orc_unwind and
.orc_unwind_ip sections.

For more details on why ORC is used instead of DWARF, see
Documentation/x86/orc-unwinder.txt - but the short version is
that it's a simplified, fundamentally more robust debugninfo
data structure, which also allows up to two orders of magnitude
faster lookups than the DWARF unwinder - which matters to
profiling workloads like perf.

Thanks to Andy Lutomirski for the performance improvement ideas:
splitting the ORC unwind table into two parallel arrays and creating a
fast lookup table to search a subset of the unwind table.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/0a6cbfb40f8da99b7a45a1a8302dc6aef16ec812.1500938583.git.jpoimboe@redhat.com
[ Extended the changelog. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-07-26 13:18:20 +02:00
Kees Cook
df3405245a x86/asm: Add suffix macro for GEN_*_RMWcc()
The coming x86 refcount protection needs to be able to add trailing
instructions to the GEN_*_RMWcc() operations. This extracts the
difference between the goto/non-goto cases so the helper macros
can be defined outside the #ifdef cases. Additionally adds argument
naming to the resulting asm for referencing from suffixed
instructions, and adds clobbers for "cc", and "cx" to let suffixes
use _ASM_CX, and retain any set flags.

Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Elena Reshetova <elena.reshetova@intel.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Hans Liljestrand <ishkamiel@gmail.com>
Cc: James Bottomley <James.Bottomley@hansenpartnership.com>
Cc: Jann Horn <jannh@google.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Serge E. Hallyn <serge@hallyn.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: arozansk@redhat.com
Cc: axboe@kernel.dk
Cc: kernel-hardening@lists.openwall.com
Cc: linux-arch <linux-arch@vger.kernel.org>
Link: http://lkml.kernel.org/r/1500921349-10803-2-git-send-email-keescook@chromium.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-07-25 11:18:09 +02:00
Andy Shevchenko
9683a64fc3 x86/io: Make readq() / writeq() API consistent
Despite the following commit:

  93093d099e ("x86: provide readq()/writeq() on 32-bit too, complete")

which says:

  ...Also, map all the APIs to the strongest ordering variant. It's way
  too easy to mess such details up in drivers and the difference between
  "memory" and "" constrained asm() constructs is in the noise range.

... we have for now only one user of this API (i.e. writeq_relaxed() in
drivers/hwtracing/intel_th/sth.c) on x86 and it does care about
"relaxed" part of it.

Moreover 32-bit support has been removed from that header, though appeared
later in specific headers that emphasizes its non-atomic context.

The rest should keep in mind a consistent picture of the __raw_IO() vs. IO()
vs. IO_relaxed() API.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Baolin Wang <baolin.wang@spreadtrum.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: intel-gfx@lists.freedesktop.org
Cc: linux-i2c@vger.kernel.org
Cc: wsa@the-dreams.de
Link: http://lkml.kernel.org/r/20170630170934.83028-6-andriy.shevchenko@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-07-24 11:18:21 +02:00
Andy Shevchenko
eabc2a7c49 x86/io: Remove xlate_dev_kmem_ptr() duplication
Generic header defines xlate_dev_kmem_ptr().

Reuse it from generic header and remove in x86 code.
Move a description to the generic header as well.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Baolin Wang <baolin.wang@spreadtrum.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: intel-gfx@lists.freedesktop.org
Cc: linux-i2c@vger.kernel.org
Cc: wsa@the-dreams.de
Link: http://lkml.kernel.org/r/20170630170934.83028-5-andriy.shevchenko@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-07-24 11:18:21 +02:00
Andy Shevchenko
c2327da06b x86/io: Remove mem*io() duplications
Generic header defines memset_io, memcpy_fromio(). and memcpy_toio().

Reuse them from generic header and remove in x86 code.
Move the descriptions to the generic header as well.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Baolin Wang <baolin.wang@spreadtrum.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: intel-gfx@lists.freedesktop.org
Cc: linux-i2c@vger.kernel.org
Cc: wsa@the-dreams.de
Link: http://lkml.kernel.org/r/20170630170934.83028-4-andriy.shevchenko@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-07-24 11:18:21 +02:00