Commit Graph

4936 Commits

Author SHA1 Message Date
Peter P Waskiewicz Jr
cbc82b1726 x86: Add support for Intel Cache QoS Monitoring (CQM) detection
This patch adds support for the new Cache QoS Monitoring (CQM)
feature found in future Intel Xeon processors.  It includes the
new values to track CQM resources to the cpuinfo_x86 structure,
plus the CPUID detection routines for CQM.

CQM allows a process, or set of processes, to be tracked by the CPU
to determine the cache usage of that task group.  Using this data
from the CPU, software can be written to extract this data and
report cache usage and occupancy for a particular process, or
group of processes.

More information about Cache QoS Monitoring can be found in the
Intel (R) x86 Architecture Software Developer Manual, section 17.14.

Signed-off-by: Peter P Waskiewicz Jr <peter.p.waskiewicz.jr@intel.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Chris Webb <chris@arachsys.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Jacob Shin <jacob.w.shin@gmail.com>
Cc: Jan Beulich <JBeulich@suse.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kanaka Juvva <kanaka.d.juvva@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Steven Honeyman <stevenhoneyman@gmail.com>
Cc: Steven Rostedt <srostedt@redhat.com>
Cc: Vikas Shivappa <vikas.shivappa@linux.intel.com>
Link: http://lkml.kernel.org/r/1422038748-21397-5-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-02-25 13:53:31 +01:00
Andy Lutomirski
a66734297f perf/x86: Add /sys/devices/cpu/rdpmc=2 to allow rdpmc for all tasks
While perfmon2 is a sufficiently evil library (it pokes MSRs
directly) that breaking it is fair game, it's still useful, so we
might as well try to support it.  This allows users to write 2 to
/sys/devices/cpu/rdpmc to disable all rdpmc protection so that hack
like perfmon2 can continue to work.

At some point, if perf_event becomes fast enough to replace
perfmon2, then this can go.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Vince Weaver <vince@deater.net>
Cc: "hillf.zj" <hillf.zj@alibaba-inc.com>
Cc: Valdis Kletnieks <Valdis.Kletnieks@vt.edu>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/caac3c1c707dcca48ecbc35f4def21495856f479.1414190806.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-02-04 12:10:49 +01:00
Andy Lutomirski
7911d3f7af perf/x86: Only allow rdpmc if a perf_event is mapped
We currently allow any process to use rdpmc.  This significantly
weakens the protection offered by PR_TSC_DISABLED, and it could be
helpful to users attempting to exploit timing attacks.

Since we can't enable access to individual counters, use a very
coarse heuristic to limit access to rdpmc: allow access only when
a perf_event is mmapped.  This protects seccomp sandboxes.

There is plenty of room to further tighen these restrictions.  For
example, this allows rdpmc for any x86_pmu event, but it's only
useful for self-monitoring tasks.

As a side effect, cap_user_rdpmc will now be false for AMD uncore
events.  This isn't a real regression, since .event_idx is disabled
for these events anyway for the time being.  Whenever that gets
re-added, the cap_user_rdpmc code can be adjusted or refactored
accordingly.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Vince Weaver <vince@deater.net>
Cc: "hillf.zj" <hillf.zj@alibaba-inc.com>
Cc: Valdis Kletnieks <Valdis.Kletnieks@vt.edu>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/a2bdb3cf3a1d70c26980d7c6dddfbaa69f3182bf.1414190806.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-02-04 12:10:47 +01:00
Andy Lutomirski
22c4bd9fa9 x86: Add a comment clarifying LDT context switching
The code is correct, but only for a rather subtle reason.  This
confused me for quite a while when I read switch_mm, so clarify the
code to avoid confusing other people, too.

TBH, I wouldn't be surprised if this code was only correct by
accident.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Vince Weaver <vince@deater.net>
Cc: "hillf.zj" <hillf.zj@alibaba-inc.com>
Cc: Valdis Kletnieks <Valdis.Kletnieks@vt.edu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/0db86397f968996fb772c443c251415b0b430ddd.1414190806.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-02-04 12:10:43 +01:00
Andy Lutomirski
1e02ce4ccc x86: Store a per-cpu shadow copy of CR4
Context switches and TLB flushes can change individual bits of CR4.
CR4 reads take several cycles, so store a shadow copy of CR4 in a
per-cpu variable.

To avoid wasting a cache line, I added the CR4 shadow to
cpu_tlbstate, which is already touched in switch_mm.  The heaviest
users of the cr4 shadow will be switch_mm and __switch_to_xtra, and
__switch_to_xtra is called shortly after switch_mm during context
switch, so the cacheline is likely to be hot.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Vince Weaver <vince@deater.net>
Cc: "hillf.zj" <hillf.zj@alibaba-inc.com>
Cc: Valdis Kletnieks <Valdis.Kletnieks@vt.edu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/3a54dd3353fffbf84804398e00dfdc5b7c1afd7d.1414190806.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-02-04 12:10:42 +01:00
Andy Lutomirski
375074cc73 x86: Clean up cr4 manipulation
CR4 manipulation was split, seemingly at random, between direct
(write_cr4) and using a helper (set/clear_in_cr4).  Unfortunately,
the set_in_cr4 and clear_in_cr4 helpers also poke at the boot code,
which only a small subset of users actually wanted.

This patch replaces all cr4 access in functions that don't leave cr4
exactly the way they found it with new helpers cr4_set_bits,
cr4_clear_bits, and cr4_set_bits_and_update_boot.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Vince Weaver <vince@deater.net>
Cc: "hillf.zj" <hillf.zj@alibaba-inc.com>
Cc: Valdis Kletnieks <Valdis.Kletnieks@vt.edu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/495a10bdc9e67016b8fd3945700d46cfd5c12c2f.1414190806.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-02-04 12:10:41 +01:00
Ingo Molnar
0967160ad6 Merge branch 'x86/asm' into perf/x86, to avoid conflicts with upcoming patches
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-02-04 09:01:12 +01:00
Ingo Molnar
b3890e4704 Merge branch 'perf/hw_breakpoints' into perf/core
The new hw_breakpoint bits are now ready for v3.20, merge them
into the main branch, to avoid conflicts.

Conflicts:
	tools/perf/Documentation/perf-record.txt

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-01-28 15:48:59 +01:00
Ingo Molnar
772a9aca12 This is my accumulated x86 entry work, part 1, for 3.20. The meat
of this is an IST rework.  When an IST exception interrupts user
 space, we will handle it on the per-thread kernel stack instead of
 on the IST stack.  This sounds messy, but it actually simplifies the
 IST entry/exit code, because it eliminates some ugly games we used
 to play in order to handle rescheduling, signal delivery, etc on the
 way out of an IST exception.
 
 The IST rework introduces proper context tracking to IST exception
 handlers.  I haven't seen any bug reports, but the old code could
 have incorrectly treated an IST exception handler as an RCU extended
 quiescent state.
 
 The memory failure change (included in this pull request with
 Borislav and Tony's permission) eliminates a bunch of code that
 is no longer needed now that user memory failure handlers are
 called in process context.
 
 Finally, this includes a few on Denys' uncontroversial and Obviously
 Correct (tm) cleanups.
 
 The IST and memory failure changes have been in -next for a while.
 
 LKML references:
 
 IST rework:
 http://lkml.kernel.org/r/cover.1416604491.git.luto@amacapital.net
 
 Memory failure change:
 http://lkml.kernel.org/r/54ab2ffa301102cd6e@agluck-desk.sc.intel.com
 
 Denys' cleanups:
 http://lkml.kernel.org/r/1420927210-19738-1-git-send-email-dvlasenk@redhat.com
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Merge tag 'pr-20150114-x86-entry' of git://git.kernel.org/pub/scm/linux/kernel/git/luto/linux into x86/asm

Pull x86/entry enhancements from Andy Lutomirski:

" This is my accumulated x86 entry work, part 1, for 3.20.  The meat
  of this is an IST rework.  When an IST exception interrupts user
  space, we will handle it on the per-thread kernel stack instead of
  on the IST stack.  This sounds messy, but it actually simplifies the
  IST entry/exit code, because it eliminates some ugly games we used
  to play in order to handle rescheduling, signal delivery, etc on the
  way out of an IST exception.

  The IST rework introduces proper context tracking to IST exception
  handlers.  I haven't seen any bug reports, but the old code could
  have incorrectly treated an IST exception handler as an RCU extended
  quiescent state.

  The memory failure change (included in this pull request with
  Borislav and Tony's permission) eliminates a bunch of code that
  is no longer needed now that user memory failure handlers are
  called in process context.

  Finally, this includes a few on Denys' uncontroversial and Obviously
  Correct (tm) cleanups.

  The IST and memory failure changes have been in -next for a while.

  LKML references:

  IST rework:
  http://lkml.kernel.org/r/cover.1416604491.git.luto@amacapital.net

  Memory failure change:
  http://lkml.kernel.org/r/54ab2ffa301102cd6e@agluck-desk.sc.intel.com

  Denys' cleanups:
  http://lkml.kernel.org/r/1420927210-19738-1-git-send-email-dvlasenk@redhat.com
"

This tree semantically depends on and is based on the following RCU commit:

  734d168013 ("rcu: Make rcu_nmi_enter() handle nesting")

... and for that reason won't be pushed upstream before the RCU bits hit Linus's tree.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-01-28 15:33:26 +01:00
Andy Lutomirski
3669ef9fa7 x86, tls: Interpret an all-zero struct user_desc as "no segment"
The Witcher 2 did something like this to allocate a TLS segment index:

        struct user_desc u_info;
        bzero(&u_info, sizeof(u_info));
        u_info.entry_number = (uint32_t)-1;

        syscall(SYS_set_thread_area, &u_info);

Strictly speaking, this code was never correct.  It should have set
read_exec_only and seg_not_present to 1 to indicate that it wanted
to find a free slot without putting anything there, or it should
have put something sensible in the TLS slot if it wanted to allocate
a TLS entry for real.  The actual effect of this code was to
allocate a bogus segment that could be used to exploit espfix.

The set_thread_area hardening patches changed the behavior, causing
set_thread_area to return -EINVAL and crashing the game.

This changes set_thread_area to interpret this as a request to find
a free slot and to leave it empty, which isn't *quite* what the game
expects but should be close enough to keep it working.  In
particular, using the code above to allocate two segments will
allocate the same segment both times.

According to FrostbittenKing on Github, this fixes The Witcher 2.

If this somehow still causes problems, we could instead allocate
a limit==0 32-bit data segment, but that seems rather ugly to me.

Fixes: 41bdc78544 x86/tls: Validate TLS entries to protect espfix
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: stable@vger.kernel.org
Cc: torvalds@linux-foundation.org
Link: http://lkml.kernel.org/r/0cb251abe1ff0958b8e468a9a9a905b80ae3a746.1421954363.git.luto@amacapital.net
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-01-22 21:45:07 +01:00
Andy Lutomirski
e30ab185c4 x86, tls, ldt: Stop checking lm in LDT_empty
32-bit programs don't have an lm bit in their ABI, so they can't
reliably cause LDT_empty to return true without resorting to memset.
They shouldn't need to do this.

This should fix a longstanding, if minor, issue in all 64-bit kernels
as well as a potential regression in the TLS hardening code.

Fixes: 41bdc78544 x86/tls: Validate TLS entries to protect espfix
Cc: stable@vger.kernel.org
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: torvalds@linux-foundation.org
Link: http://lkml.kernel.org/r/72a059de55e86ad5e2935c80aa91880ddf19d07c.1421954363.git.luto@amacapital.net
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-01-22 21:11:06 +01:00
Dave Hansen
c922228efe x86, mpx: Fix potential performance issue on unmaps
The 3.19 merge window saw some TLB modifications merged which caused a
performance regression. They were fixed in commit 045bbb9fa.

Once that fix was applied, I also noticed that there was a small
but intermittent regression still present.  It was not present
consistently enough to bisect reliably, but I'm fairly confident
that it came from (my own) MPX patches.  The source was reading
a relatively unused field in the mm_struct via arch_unmap.

I also noted that this code was in the main instruction flow of
do_munmap() and probably had more icache impact than we want.

This patch does two things:
1. Adds a static (via Kconfig) and dynamic (via cpuid) check
   for MPX with cpu_feature_enabled().  This keeps us from
   reading that cacheline in the mm and trades it for a check
   of the global CPUID variables at least on CPUs without MPX.
2. Adds an unlikely() to ensure that the MPX call ends up out
   of the main instruction flow in do_munmap().  I've added
   a detailed comment about why this was done and why we want
   it even on systems where MPX is present.

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: luto@amacapital.net
Cc: Dave Hansen <dave@sr71.net>
Link: http://lkml.kernel.org/r/20150108223021.AEEAB987@viggo.jf.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-01-22 21:11:06 +01:00
Jiang Liu
8abb850a03 x86/xen: Override ACPI IRQ management callback __acpi_unregister_gsi
Xen overrides __acpi_register_gsi and leaves __acpi_unregister_gsi as is.
That means, an IRQ allocated by acpi_register_gsi_xen_hvm() or
acpi_register_gsi_xen() will be freed by acpi_unregister_gsi_ioapic(),
which may cause undesired effects. So override __acpi_unregister_gsi to
NULL for safety.

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Tested-by: Sander Eikelenboom <linux@eikelenboom.it>
Cc: Tony Luck <tony.luck@intel.com>
Cc: xen-devel@lists.xenproject.org
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Graeme Gregory <graeme.gregory@linaro.org>
Cc: Lv Zheng <lv.zheng@intel.com>
Link: http://lkml.kernel.org/r/1421720467-7709-4-git-send-email-jiang.liu@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-01-20 11:44:41 +01:00
Denys Vlasenko
af9cfe270d x86: entry_64.S: delete unused code
A define, two macros and an unreferenced bit of assembly are gone.

Acked-by: Borislav Petkov <bp@suse.de>
CC: Linus Torvalds <torvalds@linux-foundation.org>
CC: Oleg Nesterov <oleg@redhat.com>
CC: "H. Peter Anvin" <hpa@zytor.com>
CC: Andy Lutomirski <luto@amacapital.net>
CC: Frederic Weisbecker <fweisbec@gmail.com>
CC: X86 ML <x86@kernel.org>
CC: Alexei Starovoitov <ast@plumgrid.com>
CC: Will Drewry <wad@chromium.org>
CC: Kees Cook <keescook@chromium.org>
CC: linux-kernel@vger.kernel.org
Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
2015-01-13 14:00:33 -08:00
Luck, Tony
d4812e169d x86, mce: Get rid of TIF_MCE_NOTIFY and associated mce tricks
We now switch to the kernel stack when a machine check interrupts
during user mode.  This means that we can perform recovery actions
in the tail of do_machine_check()

Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
2015-01-07 07:47:42 -08:00
Andy Lutomirski
bced35b65a x86, traps: Add ist_begin_non_atomic and ist_end_non_atomic
In some IST handlers, if the interrupt came from user mode,
we can safely enable preemption.  Add helpers to do it safely.

This is intended to be used my the memory failure code in
do_machine_check.

Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
2015-01-02 10:22:46 -08:00
Andy Lutomirski
83653c16da x86: Clean up current_stack_pointer
There's no good reason for it to be a macro, and x86_64 will want to
use it, so it should be in a header.

Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
2015-01-02 10:22:46 -08:00
Andy Lutomirski
9592747538 x86, traps: Track entry into and exit from IST context
We currently pretend that IST context is like standard exception
context, but this is incorrect.  IST entries from userspace are like
standard exceptions except that they use per-cpu stacks, so they are
atomic.  IST entries from kernel space are like NMIs from RCU's
perspective -- they are not quiescent states even if they
interrupted the kernel during a quiescent state.

Add and use ist_enter and ist_exit to track IST context.  Even
though x86_32 has no IST stacks, we track these interrupts the same
way.

This fixes two issues:

 - Scheduling from an IST interrupt handler will now warn.  It would
   previously appear to work as long as we got lucky and nothing
   overwrote the stack frame.  (I don't know of any bugs in this
   that would trigger the warning, but it's good to be on the safe
   side.)

 - RCU handling in IST context was dangerous.  As far as I know,
   only machine checks were likely to trigger this, but it's good to
   be on the safe side.

Note that the machine check handlers appears to have been missing
any context tracking at all before this patch.

Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
2015-01-02 10:22:46 -08:00
Ingo Molnar
2aba73a614 This is hopefully the last vdso fix for 3.19. It should be very
safe (it just adds a volatile).
 
 I don't think it fixes an actual bug (the __getcpu calls in the
 pvclock code may not have been needed in the first place), but
 discussion on that point is ongoing.
 
 It also fixes a big performance issue in 3.18 and earlier in which
 the lsl instructions in vclock_gettime got hoisted so far up the
 function that they happened even when the function they were in was
 never called.  n 3.19, the performance issue seems to be gone due to
 the whims of my compiler and some interaction with a branch that's
 now gone.
 
 I'll hopefully have a much bigger overhaul of the pvclock code
 for 3.20, but it needs careful review.
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Merge tag 'pr-20141223-x86-vdso' of git://git.kernel.org/pub/scm/linux/kernel/git/luto/linux into x86/urgent

Pull VDSO fix from Andy Lutomirski:

 "This is hopefully the last vdso fix for 3.19.  It should be very
  safe (it just adds a volatile).

  I don't think it fixes an actual bug (the __getcpu calls in the
  pvclock code may not have been needed in the first place), but
  discussion on that point is ongoing.

  It also fixes a big performance issue in 3.18 and earlier in which
  the lsl instructions in vclock_gettime got hoisted so far up the
  function that they happened even when the function they were in was
  never called.  n 3.19, the performance issue seems to be gone due to
  the whims of my compiler and some interaction with a branch that's
  now gone.

  I'll hopefully have a much bigger overhaul of the pvclock code
  for 3.20, but it needs careful review."

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-01-01 22:21:22 +01:00
Andy Lutomirski
1ddf0b1b11 x86, vdso: Use asm volatile in __getcpu
In Linux 3.18 and below, GCC hoists the lsl instructions in the
pvclock code all the way to the beginning of __vdso_clock_gettime,
slowing the non-paravirt case significantly.  For unknown reasons,
presumably related to the removal of a branch, the performance issue
is gone as of

e76b027e64 x86,vdso: Use LSL unconditionally for vgetcpu

but I don't trust GCC enough to expect the problem to stay fixed.

There should be no correctness issue, because the __getcpu calls in
__vdso_vlock_gettime were never necessary in the first place.

Note to stable maintainers: In 3.18 and below, depending on
configuration, gcc 4.9.2 generates code like this:

     9c3:       44 0f 03 e8             lsl    %ax,%r13d
     9c7:       45 89 eb                mov    %r13d,%r11d
     9ca:       0f 03 d8                lsl    %ax,%ebx

This patch won't apply as is to any released kernel, but I'll send a
trivial backported version if needed.

Fixes: 51c19b4f59 x86: vdso: pvclock gettime support
Cc: stable@vger.kernel.org # 3.8+
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
2014-12-23 13:05:30 -08:00
Linus Torvalds
60815cf2e0 kernel: Provide READ_ONCE and ASSIGN_ONCE
As discussed on LKML http://marc.info/?i=54611D86.4040306%40de.ibm.com
 ACCESS_ONCE might fail with specific compilers for non-scalar accesses.
 
 Here is a set of patches to tackle that problem.
 
 The first patch introduce READ_ONCE and ASSIGN_ONCE. If the data structure
 is larger than the machine word size memcpy is used and a warning is emitted.
 The next patches fix up several in-tree users of ACCESS_ONCE on non-scalar
 types.
 
 This merge does not yet contain a patch that forces ACCESS_ONCE to work only
 on scalar types. This is targetted for the next merge window as Linux next
 already contains new offenders regarding ACCESS_ONCE vs. non-scalar types.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/borntraeger/linux

Pull ACCESS_ONCE cleanup preparation from Christian Borntraeger:
 "kernel: Provide READ_ONCE and ASSIGN_ONCE

  As discussed on LKML http://marc.info/?i=54611D86.4040306%40de.ibm.com
  ACCESS_ONCE might fail with specific compilers for non-scalar
  accesses.

  Here is a set of patches to tackle that problem.

  The first patch introduce READ_ONCE and ASSIGN_ONCE.  If the data
  structure is larger than the machine word size memcpy is used and a
  warning is emitted.  The next patches fix up several in-tree users of
  ACCESS_ONCE on non-scalar types.

  This does not yet contain a patch that forces ACCESS_ONCE to work only
  on scalar types.  This is targetted for the next merge window as Linux
  next already contains new offenders regarding ACCESS_ONCE vs.
  non-scalar types"

* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/borntraeger/linux:
  s390/kvm: REPLACE barrier fixup with READ_ONCE
  arm/spinlock: Replace ACCESS_ONCE with READ_ONCE
  arm64/spinlock: Replace ACCESS_ONCE READ_ONCE
  mips/gup: Replace ACCESS_ONCE with READ_ONCE
  x86/gup: Replace ACCESS_ONCE with READ_ONCE
  x86/spinlock: Replace ACCESS_ONCE with READ_ONCE
  mm: replace ACCESS_ONCE with READ_ONCE or barriers
  kernel: Provide READ_ONCE and ASSIGN_ONCE
2014-12-20 16:48:59 -08:00
Linus Torvalds
e589c9e13a Merge branch 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 apic updates from Thomas Gleixner:
 "After stopping the full x86/apic branch, I took some time to go
  through the first block of patches again, which are mostly cleanups
  and preparatory work for the irqdomain conversion and ioapic hotplug
  support.

  Unfortunaly one of the real problematic commits was right at the
  beginning, so I rebased this portion of the pending patches without
  the offenders.

  It would be great to get this into 3.19.  That makes reworking the
  problematic parts simpler.  The usual tip testing did not unearth any
  issues and it is fully bisectible now.

  I'm pretty confident that this wont affect the calmness of the xmas
  season.

  Changes:
   - Split the convoluted io_apic.c code into domain specific parts
     (vector, ioapic, msi, htirq)
   - Introduce proper helper functions to retrieve irq specific data
     instead of open coded dereferencing of pointers
   - Preparatory work for ioapic hotplug and irqdomain conversion
   - Removal of the non functional pci-ioapic driver
   - Removal of unused irq entry stubs
   - Make native_smp_prepare_cpus() preemtible to avoid GFP_ATOMIC
     allocations for everything which is called from there.
   - Small cleanups and fixes"

* 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (36 commits)
  iommu/amd: Use helpers to access irq_cfg data structure associated with IRQ
  iommu/vt-d: Use helpers to access irq_cfg data structure associated with IRQ
  x86: irq_remapping: Use helpers to access irq_cfg data structure associated with IRQ
  x86, irq: Use helpers to access irq_cfg data structure associated with IRQ
  x86, irq: Make MSI and HT_IRQ indepenent of X86_IO_APIC
  x86, irq: Move IRQ initialization routines from io_apic.c into vector.c
  x86, irq: Move IOAPIC related declarations from hw_irq.h into io_apic.h
  x86, irq: Move HT IRQ related code from io_apic.c into htirq.c
  x86, irq: Move PCI MSI related code from io_apic.c into msi.c
  x86, irq: Replace printk(KERN_LVL) with pr_lvl() utilities
  x86, irq: Make UP version of irq_complete_move() an inline stub
  x86, irq: Move local APIC related code from io_apic.c into vector.c
  x86, irq: Introduce helpers to access struct irq_cfg
  x86, irq: Protect __clear_irq_vector() with vector_lock
  x86, irq: Rename local APIC related functions in io_apic.c as apic_xxx()
  x86, irq: Refine hw_irq.h to prepare for irqdomain support
  x86, irq: Convert irq_2_pin list to generic list
  x86, irq: Kill useless parameter 'irq_attr' of IO_APIC_get_PCI_irq_vector()
  x86, irq, acpi: Get rid of special handling of GSI for ACPI SCI
  x86, irq: Introduce helper to check whether an IOAPIC has been registered
  ...
2014-12-19 14:02:02 -08:00
Linus Torvalds
1092b596a5 Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fix from Ingo Molnar:
 "This contains a single TLS ABI validation fix from Andy Lutomirski"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/tls: Don't validate lm in set_thread_area() after all
2014-12-19 13:18:31 -08:00
Linus Torvalds
66dcff86ba 3.19 changes for KVM:
- spring cleaning: removed support for IA64, and for hardware-assisted
 virtualization on the PPC970
 - ARM, PPC, s390 all had only small fixes
 
 For x86:
 - small performance improvements (though only on weird guests)
 - usual round of hardware-compliancy fixes from Nadav
 - APICv fixes
 - XSAVES support for hosts and guests.  XSAVES hosts were broken because
 the (non-KVM) XSAVES patches inadvertently changed the KVM userspace
 ABI whenever XSAVES was enabled; hence, this part is going to stable.
 Guest support is just a matter of exposing the feature and CPUID leaves
 support.
 
 Right now KVM is broken for PPC BookE in your tree (doesn't compile).
 I'll reply to the pull request with a patch, please apply it either
 before the pull request or in the merge commit, in order to preserve
 bisectability somewhat.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM update from Paolo Bonzini:
 "3.19 changes for KVM:

   - spring cleaning: removed support for IA64, and for hardware-
     assisted virtualization on the PPC970

   - ARM, PPC, s390 all had only small fixes

  For x86:
   - small performance improvements (though only on weird guests)
   - usual round of hardware-compliancy fixes from Nadav
   - APICv fixes
   - XSAVES support for hosts and guests.  XSAVES hosts were broken
     because the (non-KVM) XSAVES patches inadvertently changed the KVM
     userspace ABI whenever XSAVES was enabled; hence, this part is
     going to stable.  Guest support is just a matter of exposing the
     feature and CPUID leaves support"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (179 commits)
  KVM: move APIC types to arch/x86/
  KVM: PPC: Book3S: Enable in-kernel XICS emulation by default
  KVM: PPC: Book3S HV: Improve H_CONFER implementation
  KVM: PPC: Book3S HV: Fix endianness of instruction obtained from HEIR register
  KVM: PPC: Book3S HV: Remove code for PPC970 processors
  KVM: PPC: Book3S HV: Tracepoints for KVM HV guest interactions
  KVM: PPC: Book3S HV: Simplify locking around stolen time calculations
  arch: powerpc: kvm: book3s_paired_singles.c: Remove unused function
  arch: powerpc: kvm: book3s_pr.c: Remove unused function
  arch: powerpc: kvm: book3s.c: Remove some unused functions
  arch: powerpc: kvm: book3s_32_mmu.c: Remove unused function
  KVM: PPC: Book3S HV: Check wait conditions before sleeping in kvmppc_vcore_blocked
  KVM: PPC: Book3S HV: ptes are big endian
  KVM: PPC: Book3S HV: Fix inaccuracies in ICP emulation for H_IPI
  KVM: PPC: Book3S HV: Fix KSM memory corruption
  KVM: PPC: Book3S HV: Fix an issue where guest is paused on receiving HMI
  KVM: PPC: Book3S HV: Fix computation of tlbie operand
  KVM: PPC: Book3S HV: Add missing HPTE unlock
  KVM: PPC: BookE: Improve irq inject tracepoint
  arm/arm64: KVM: Require in-kernel vgic for the arch timers
  ...
2014-12-18 16:05:28 -08:00
Andy Lutomirski
3fb2f4237b x86/tls: Don't validate lm in set_thread_area() after all
It turns out that there's a lurking ABI issue.  GCC, when
compiling this in a 32-bit program:

struct user_desc desc = {
	.entry_number    = idx,
	.base_addr       = base,
	.limit           = 0xfffff,
	.seg_32bit       = 1,
	.contents        = 0, /* Data, grow-up */
	.read_exec_only  = 0,
	.limit_in_pages  = 1,
	.seg_not_present = 0,
	.useable         = 0,
};

will leave .lm uninitialized.  This means that anything in the
kernel that reads user_desc.lm for 32-bit tasks is unreliable.

Revert the .lm check in set_thread_area().  The value never did
anything in the first place.

Fixes: 0e58af4e1d ("x86/tls: Disallow unusual TLS segments")
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org # Only if 0e58af4e1d is backported
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/d7875b60e28c512f6a6fc0baf5714d58e7eaadbb.1418856405.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-12-18 12:12:26 +01:00
Christian Borntraeger
4f9d1382e6 x86/spinlock: Replace ACCESS_ONCE with READ_ONCE
ACCESS_ONCE does not work reliably on non-scalar types. For
example gcc 4.6 and 4.7 might remove the volatile tag for such
accesses during the SRA (scalar replacement of aggregates) step
(https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58145)

Change the spinlock code to replace ACCESS_ONCE with READ_ONCE.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2014-12-18 09:54:38 +01:00
Paolo Bonzini
cb5281a572 KVM: move APIC types to arch/x86/
They are not used anymore by IA64, move them away.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-12-18 09:39:51 +01:00
Linus Torvalds
eb64c3c6cd xen: additional features for 3.19-rc0
- Linear p2m for x86 PV guests which simplifies the p2m code, improves
   performance and will allow for > 512 GB PV guests in the future.
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Merge tag 'stable/for-linus-3.19-rc0b-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull additional xen update from David Vrabel:
 "Xen: additional features for 3.19-rc0

   - Linear p2m for x86 PV guests which simplifies the p2m code,
     improves performance and will allow for > 512 GB PV guests in the
     future.

  A last-minute, configuration specific issue was discovered with this
  change which is why it was not included in my previous pull request.
  This is now been fixed and tested"

* tag 'stable/for-linus-3.19-rc0b-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen: switch to post-init routines in xen mmu.c earlier
  Revert "swiotlb-xen: pass dev_addr to swiotlb_tbl_unmap_single"
  xen: annotate xen_set_identity_and_remap_chunk() with __init
  xen: introduce helper functions to do safe read and write accesses
  xen: Speed up set_phys_to_machine() by using read-only mappings
  xen: switch to linear virtual mapped sparse p2m list
  xen: Hide get_phys_to_machine() to be able to tune common path
  x86: Introduce function to get pmd entry pointer
  xen: Delay invalidating extra memory
  xen: Delay m2p_override initialization
  xen: Delay remapping memory of pv-domain
  xen: use common page allocation function in p2m.c
  xen: Make functions static
  xen: fix some style issues in p2m.c
2014-12-16 13:23:03 -08:00
Jiang Liu
11d686e956 x86, irq: Move IRQ initialization routines from io_apic.c into vector.c
Move IRQ initialization routines from io_apic.c into vector.c,
preparing for enabling hierarchy irqdomain.

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Prarit Bhargava <prarit@redhat.com>
Link: http://lkml.kernel.org/r/1414397531-28254-15-git-send-email-jiang.liu@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-12-16 14:08:17 +01:00
Jiang Liu
8643e28da2 x86, irq: Move IOAPIC related declarations from hw_irq.h into io_apic.h
Clean up code by moving IOAPIC related declarations from hw_irq.h into
io_apic.h.

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@linux.intel.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Matt Fleming <matt.fleming@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Christian Gmeiner <christian.gmeiner@gmail.com>
Cc: Aubrey <aubrey.li@linux.intel.com>
Cc: Ryan Desfosses <ryan@desfo.org>
Cc: Quentin Lambert <lambert.quentin@gmail.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: http://lkml.kernel.org/r/1414397531-28254-14-git-send-email-jiang.liu@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-12-16 14:08:17 +01:00
Jiang Liu
443809828c x86, irq: Move PCI MSI related code from io_apic.c into msi.c
Create arch/x86/kernel/apic/msi.c to host MSI related code,
preparing for enabling hierarchy irqdomain.

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Prarit Bhargava <prarit@redhat.com>
Link: http://lkml.kernel.org/r/1414397531-28254-12-git-send-email-jiang.liu@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-12-16 14:08:17 +01:00
Thomas Gleixner
f0e5bf7583 x86, irq: Make UP version of irq_complete_move() an inline stub
No point for having an empty real function.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-12-16 14:08:16 +01:00
Jiang Liu
74afab7af7 x86, irq: Move local APIC related code from io_apic.c into vector.c
Create arch/x86/kernel/apic/vector.c to host local APIC related code,
prepare for making MSI/HT_IRQ independent of IOAPIC.

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Grant Likely <grant.likely@linaro.org>
Link: http://lkml.kernel.org/r/1414397531-28254-10-git-send-email-jiang.liu@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-12-16 14:08:16 +01:00
Jiang Liu
55a0e2b122 x86, irq: Introduce helpers to access struct irq_cfg
Change irq_cfg() from static to extern, also introduce helper function
irqd_cfg(). Later we can rewrite these two helpers when enabling
hierarchy irqdomain.

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Grant Likely <grant.likely@linaro.org>
Link: http://lkml.kernel.org/r/1414397531-28254-9-git-send-email-jiang.liu@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-12-16 14:08:16 +01:00
Jiang Liu
cb39288cd6 x86, irq: Rename local APIC related functions in io_apic.c as apic_xxx()
Rename local APIC related functions in io_apic.c as apic_xxx() instead
of ioapic_xxx(), later they will be moved into separate file.

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Grant Likely <grant.likely@linaro.org>
Link: http://lkml.kernel.org/r/1414397531-28254-7-git-send-email-jiang.liu@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-12-16 14:08:16 +01:00
Jiang Liu
26011eee04 x86, irq: Refine hw_irq.h to prepare for irqdomain support
Refine hw_irq.h to prepare for irqdomain support by:

1) guarding common APIC related interfaces with CONFIG_X86_LOCAL_APIC
2) guarding interrupt remapping related interfaces with CONFIG_IRQ_REMAP
3) guarding IOAPIC related interfaces with CONFIG_X86_IO_APIC

No functional changes.

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Prarit Bhargava <prarit@redhat.com>
Link: http://lkml.kernel.org/r/1414397531-28254-6-git-send-email-jiang.liu@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-12-16 14:08:16 +01:00
Yinghai Lu
a178b87b20 x86, irq: Convert irq_2_pin list to generic list
Use generic list to replace private list implementation so we can use
the existing helper functions.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Grant Likely <grant.likely@linaro.org>
Link: http://lkml.kernel.org/r/1414397531-28254-5-git-send-email-jiang.liu@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
Cc: Joerg Roedel <joro@8bytes.org>
2014-12-16 14:08:16 +01:00
Jiang Liu
25d0d35ed7 x86, irq: Kill useless parameter 'irq_attr' of IO_APIC_get_PCI_irq_vector()
None of the callers requires irq_attr to be filled
in. IO_APIC_get_PCI_irq_vector() does not do anything useful with it
either.

Remove the parameter and fixup the call sites.

[ tglx: Massaged changelog ]

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Ryan Desfosses <ryan@desfo.org>
Cc: Quentin Lambert <lambert.quentin@gmail.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: http://lkml.kernel.org/r/1414397531-28254-4-git-send-email-jiang.liu@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-12-16 14:08:16 +01:00
Jiang Liu
e89900c9ad x86, irq: Introduce helper to check whether an IOAPIC has been registered
Introduce acpi_ioapic_registered() to check whether an IOAPIC has already
been registered, it will be used when enabling IOAPIC hotplug.

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Len Brown <len.brown@intel.com>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Prarit Bhargava <prarit@redhat.com>
Link: http://lkml.kernel.org/r/1414387308-27148-18-git-send-email-jiang.liu@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-12-16 14:08:15 +01:00
Jiang Liu
15516a3b86 x86, irq, ACPI: Implement interfaces to support ACPI based IOAPIC hot-removal
Implement acpi_unregister_ioapic() to support ACPI based IOAPIC hot-removal.
An IOAPIC could only be removed when all its pins are unused.

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Len Brown <len.brown@intel.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Prarit Bhargava <prarit@redhat.com>
Link: http://lkml.kernel.org/r/1414387308-27148-17-git-send-email-jiang.liu@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-12-16 14:08:15 +01:00
Jiang Liu
35ef9c941c x86, irq: Refine mp_register_ioapic() to prepare for IOAPIC hotplug
Refine mp_register_ioapic() to prepare for IOAPIC hotplug by:
1) change return value from void to int.
2) check for gsi range conflicts
3) check for IOAPIC physical address conflicts
4) enhance the way to allocate IOAPIC index

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Prarit Bhargava <prarit@redhat.com>
Link: http://lkml.kernel.org/r/1414387308-27148-14-git-send-email-jiang.liu@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-12-16 14:08:15 +01:00
Jiang Liu
67dc5e701f x86, irq: Remove __init marker for functions will be used by IOAPIC hotplug
Remove __init marker for functions which will be used by IOAPIC hotplug
at runtime.

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Prarit Bhargava <prarit@redhat.com>
Link: http://lkml.kernel.org/r/1414387308-27148-12-git-send-email-jiang.liu@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-12-16 14:08:15 +01:00
Jan Beulich
2414e021ac x86: Avoid building unused IRQ entry stubs
When X86_LOCAL_APIC (i.e. unconditionally on x86-64),
first_system_vector will never end up being higher than
LOCAL_TIMER_VECTOR (0xef), and hence building stubs for vectors
0xef...0xff is pointlessly reducing code density. Deal with this at
build time already.

Taking into consideration that X86_64 implies X86_LOCAL_APIC, also
simplify (and hence make easier to read and more consistent with the
change done here) some #if-s in arch/x86/kernel/irqinit.c.

While we could further improve the packing of the IRQ entry stubs (the
four ones now left in the last set could be fit into the four padding
bytes each of the final four sets have) this doesn't seem to provide
any real benefit: Both irq_entries_start and common_interrupt getting
cache line aligned, eliminating the 30th set would just produce 32
bytes of padding between the 29th and common_interrupt.

[ tglx: Folded lguest fix from Dan Carpenter ]

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: lguest@lists.ozlabs.org
Cc: Rusty Russell <rusty@rustcorp.com.au>
Link: http://lkml.kernel.org/r/54574D5F0200007800044389@mail.emea.novell.com
Link: http://lkml.kernel.org/r/20141115185718.GB6530@mwanda
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-12-16 14:08:14 +01:00
Jan Beulich
e106798259 x86: irq: Fix placement of mp_should_keep_irq()
While f3761db164 ("x86, irq: Fix build error caused by
9eabc99a635a77cbf09") addressed the original build problem,
declaration, inline stub, and definition still seem misplaced: It isn't
really IO-APIC related, and it's being used solely in arch/x86/pci/.
This also means stubbing it out when !CONFIG_X86_IO_APIC was at least
questionable.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Link: http://lkml.kernel.org/r/545747BE020000780004436E@mail.emea.novell.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-12-16 14:08:14 +01:00
Jiang Liu
e32c67e0cb x86, irq: Provide empty send_cleanup_vector() stub for UP builds
Define an empty send_cleanup_vector() for UP kernel to fix link error
of undefined reference, which is used by uv_irq and irq_remapping.

[ tglx: Made it an inline stub and moved it ahead of the file split
  	changes ]

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Link: http://lkml.kernel.org/r/1414397531-28254-21-git-send-email-jiang.liu@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-12-16 14:08:14 +01:00
Linus Torvalds
536e89ee53 Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Ingo Molnar:
 "Misc fixes (mainly Andy's TLS fixes), plus a cleanup"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/tls: Disallow unusual TLS segments
  x86/tls: Validate TLS entries to protect espfix
  MAINTAINERS: Add me as x86 VDSO submaintainer
  x86/asm: Unify segment selector defines
  x86/asm: Guard against building the 32/64-bit versions of the asm-offsets*.c file directly
  x86_64, switch_to(): Load TLS descriptors before switching DS and ES
  x86/mm: Use min() instead of min_t() in the e820 printout code
  x86/mm: Fix zone ranges boot printout
  x86/doc: Update documentation after file shuffling
2014-12-14 11:51:50 -08:00
Linus Torvalds
f96fe22567 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull another networking update from David Miller:
 "Small follow-up to the main merge pull from the other day:

  1) Alexander Duyck's DMA memory barrier patch set.

  2) cxgb4 driver fixes from Karen Xie.

  3) Add missing export of fixed_phy_register() to modules, from Mark
     Salter.

  4) DSA bug fixes from Florian Fainelli"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (24 commits)
  net/macb: add TX multiqueue support for gem
  linux/interrupt.h: remove the definition of unused tasklet_hi_enable
  jme: replace calls to redundant function
  net: ethernet: davicom: Allow to select DM9000 for nios2
  net: ethernet: smsc: Allow to select SMC91X for nios2
  cxgb4: Add support for QSA modules
  libcxgbi: fix freeing skb prematurely
  cxgb4i: use set_wr_txq() to set tx queues
  cxgb4i: handle non-pdu-aligned rx data
  cxgb4i: additional types of negative advice
  cxgb4/cxgb4i: set the max. pdu length in firmware
  cxgb4i: fix credit check for tx_data_wr
  cxgb4i: fix tx immediate data credit check
  net: phy: export fixed_phy_register()
  fib_trie: Fix trie balancing issue if new node pushes down existing node
  vlan: Add ability to always enable TSO/UFO
  r8169:update rtl8168g pcie ephy parameter
  net: dsa: bcm_sf2: force link for all fixed PHY devices
  fm10k/igb/ixgbe: Use dma_rmb on Rx descriptor reads
  r8169: Use dma_rmb() and dma_wmb() for DescOwn checks
  ...
2014-12-12 16:11:12 -08:00
Linus Torvalds
9d050966e2 xen: features and fixes for 3.19-rc0
- Fully support non-coherent devices on ARM by introducing the
   mechanisms to request the hypervisor to perform the required cache
   maintainance operations.
 
 - A number of pciback bug fixes and cleanups.  Notably a deadlock fix
   if a PCI device was manually uunbound and a fix for incorrectly
   restoring state after a function reset.
 
 - In x86 PVHVM guests, use the APIC for interrupts if this has been
   virtualized by the hardware.  This reduces the number of interrupt-
   related VM exits on such hardware.
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Merge tag 'stable/for-linus-3.19-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen features and fixes from David Vrabel:

 - Fully support non-coherent devices on ARM by introducing the
   mechanisms to request the hypervisor to perform the required cache
   maintainance operations.

 - A number of pciback bug fixes and cleanups.  Notably a deadlock fix
   if a PCI device was manually uunbound and a fix for incorrectly
   restoring state after a function reset.

 - In x86 PVHVM guests, use the APIC for interrupts if this has been
   virtualized by the hardware.  This reduces the number of interrupt-
   related VM exits on such hardware.

* tag 'stable/for-linus-3.19-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: (26 commits)
  Revert "swiotlb-xen: pass dev_addr to swiotlb_tbl_unmap_single"
  xen/pci: Use APIC directly when APIC virtualization hardware is available
  xen/pci: Defer initialization of MSI ops on HVM guests
  xen-pciback: drop SR-IOV VFs when PF driver unloads
  xen/pciback: Restore configuration space when detaching from a guest.
  PCI: Expose pci_load_saved_state for public consumption.
  xen/pciback: Remove tons of dereferences
  xen/pciback: Print out the domain owning the device.
  xen/pciback: Include the domain id if removing the device whilst still in use
  driver core: Provide an wrapper around the mutex to do lockdep warnings
  xen/pciback: Don't deadlock when unbinding.
  swiotlb-xen: pass dev_addr to swiotlb_tbl_unmap_single
  swiotlb-xen: call xen_dma_sync_single_for_device when appropriate
  swiotlb-xen: remove BUG_ON in xen_bus_to_phys
  swiotlb-xen: pass dev_addr to xen_dma_unmap_page and xen_dma_sync_single_for_cpu
  xen/arm: introduce GNTTABOP_cache_flush
  xen/arm/arm64: introduce xen_arch_need_swiotlb
  xen/arm/arm64: merge xen/mm32.c into xen/mm.c
  xen/arm: use hypercall to flush caches in map_page
  xen: add a dma_addr_t dev_addr argument to xen_dma_map_page
  ...
2014-12-11 18:15:33 -08:00
Alexander Duyck
1077fa36f2 arch: Add lightweight memory barriers dma_rmb() and dma_wmb()
There are a number of situations where the mandatory barriers rmb() and
wmb() are used to order memory/memory operations in the device drivers
and those barriers are much heavier than they actually need to be.  For
example in the case of PowerPC wmb() calls the heavy-weight sync
instruction when for coherent memory operations all that is really needed
is an lsync or eieio instruction.

This commit adds a coherent only version of the mandatory memory barriers
rmb() and wmb().  In most cases this should result in the barrier being the
same as the SMP barriers for the SMP case, however in some cases we use a
barrier that is somewhere in between rmb() and smp_rmb().  For example on
ARM the rmb barriers break down as follows:

  Barrier   Call     Explanation
  --------- -------- ----------------------------------
  rmb()     dsb()    Data synchronization barrier - system
  dma_rmb() dmb(osh) data memory barrier - outer sharable
  smp_rmb() dmb(ish) data memory barrier - inner sharable

These new barriers are not as safe as the standard rmb() and wmb().
Specifically they do not guarantee ordering between coherent and incoherent
memories.  The primary use case for these would be to enforce ordering of
reads and writes when accessing coherent memory that is shared between the
CPU and a device.

It may also be noted that there is no dma_mb().  Most architectures don't
provide a good mechanism for performing a coherent only full barrier without
resorting to the same mechanism used in mb().  As such there isn't much to
be gained in trying to define such a function.

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Michael Ellerman <michael@ellerman.id.au>
Cc: Michael Neuling <mikey@neuling.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: David Miller <davem@davemloft.net>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-11 21:15:06 -05:00
Alexander Duyck
8a44971841 arch: Cleanup read_barrier_depends() and comments
This patch is meant to cleanup the handling of read_barrier_depends and
smp_read_barrier_depends.  In multiple spots in the kernel headers
read_barrier_depends is defined as "do {} while (0)", however we then go
into the SMP vs non-SMP sections and have the SMP version reference
read_barrier_depends, and the non-SMP define it as yet another empty
do/while.

With this commit I went through and cleaned out the duplicate definitions
and reduced the number of definitions down to 2 per header.  In addition I
moved the 50 line comments for the macro from the x86 and mips headers that
defined it as an empty do/while to those that were actually defining the
macro, alpha and blackfin.

Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-11 21:15:05 -05:00