We don't use irq_enable_sysexit on 64-bit kernels any more.
Remove all the paravirt and Xen machinery to support it on
64-bit kernels.
Tested-by: NBoris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: NAndy Lutomirski <luto@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Denys Vlasenko <vda.linux@googlemail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/8a03355698fe5b94194e9e7360f19f91c1b2cf1f.1428100853.git.luto@kernel.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>

For fixed sized copies, copy_to_user() will utilize
__put_user_size() fastpaths. However, it is missing the
translation for 64-bit copies on x86/32.

Testing on a Pinetrail Atom, the 64 bit put_user() fastpath
is substantially faster than the generic copy_to_user()
fallback.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Borislav Petkov <bp@alien8.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: intel-gfx@lists.freedesktop.org
Link: http://lkml.kernel.org/r/1429091486-11443-1-git-send-email-chris@chris-wilson.co.ukSigned-off-by: NIngo Molnar <mingo@kernel.org>

Make it a local symbol so that it doesn't appear in objdump
output.

No functionality change - code remains the same, just the global
label disappears:

	 ffffffff81039dbe:       bf 03 00 00 00          mov    $0x3,%edi
	 ffffffff81039dc3:       31 c0                   xor    %eax,%eax
	 ffffffff81039dc5:       e8 b6 fd ff ff          callq  ffffffff81039b80 <x86_acpi_enter_sleep_state>
	-ffffffff81039dca:       eb 00                   jmp    ffffffff81039dcc <resume_point>
	-
	-ffffffff81039dcc <resume_point>:
	+ffffffff81039dca:       eb 00                   jmp    ffffffff81039dcc <do_suspend_lowlevel+0x9c>
	 ffffffff81039dcc:       48 c7 c0 80 1a ca 82    mov    $0xffffffff82ca1a80,%rax
	 ffffffff81039dd3:       48 8b 98 e2 00 00 00    mov    0xe2(%rax),%rbx
	 ffffffff81039dda:       0f 22 e3                mov    %rbx,%cr4
Signed-off-by: NBorislav Petkov <bp@suse.de>
Cc: <linux-pm@vger.kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
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: Len Brown <len.brown@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1429080614-22610-1-git-send-email-bp@alien8.deSigned-off-by: NIngo Molnar <mingo@kernel.org>

... so that they don't appear in the object file and thus in
objdump output. They're local anyway and have a meaning only
within that file.

No functionality change.
Signed-off-by: NBorislav Petkov <bp@suse.de>
Acked-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: NPavel Machek <pavel@ucw.cz>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-pm@vger.kernel.org
Link: http://lkml.kernel.org/r/1428867906-12016-1-git-send-email-bp@alien8.deSigned-off-by: NIngo Molnar <mingo@kernel.org>

Signed-off-by: NBrian Gerst <brgerst@gmail.com>
Acked-by: NAndy Lutomirski <luto@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Link: http://lkml.kernel.org/r/1428844486-6638-2-git-send-email-brgerst@gmail.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Merge common values for 32-bit native and compat.
Signed-off-by: NBrian Gerst <brgerst@gmail.com>
Acked-by: NAndy Lutomirski <luto@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Link: http://lkml.kernel.org/r/1428844486-6638-1-git-send-email-brgerst@gmail.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

I don't see why we report e.g. orix_ax, which is not always
meaningful, but don't report ax, which is meaningful.
Signed-off-by: NDenys Vlasenko <dvlasenk@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1428671219-29341-4-git-send-email-dvlasenk@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

user_64bit_mode(regs) basically checks regs->cs to point to a
64-bit segment. This check used to be unreliable here because
regs->cs was not always correct in syscalls.

Now regs->cs is always correct: in syscalls, in interrupts, in
exceptions. No need to emply heuristics here.
Signed-off-by: NDenys Vlasenko <dvlasenk@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1428671219-29341-3-git-send-email-dvlasenk@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Yes, it is true that cx contains return address.
It's not clear why we trash it.
Stop doing that.
Signed-off-by: NDenys Vlasenko <dvlasenk@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1428671219-29341-2-git-send-email-dvlasenk@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

After recent changes to syscall entry points,
user_regs->{cs,ss,sp} are always correct. (They used to be
undefined while in syscalls).

We can report them reliably, without guessing.
Signed-off-by: NDenys Vlasenko <dvlasenk@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1428671219-29341-1-git-send-email-dvlasenk@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

After TESTs, use logically correct JNZ mnemonic instead of JNE.

This doesn't change code:

  md5:
   c3005b39a11fe582b7df7908561ad4ee  entry_32.o.before.asm
   c3005b39a11fe582b7df7908561ad4ee  entry_32.o.after.asm
Signed-off-by: NDenys Vlasenko <dvlasenk@redhat.com>
Acked-by: NAndy Lutomirski <luto@kernel.org>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1428689620-21881-1-git-send-email-dvlasenk@redhat.com
[ Added object file comparison. ]
Signed-off-by: NIngo Molnar <mingo@kernel.org>

Update the check for UV2000/3000.  Note when the HUB is not recognized.
Signed-off-by: NMike Travis <travis@sgi.com>
Acked-by: NHedi Berriche <hedi@sgi.com>
Acked-by: NDimitri Sivanich <sivanich@sgi.com>
Link: http://lkml.kernel.org/r/20150409182629.267239403@asylum.americas.sgi.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Fix a bug in the OEM check function that determines if the
system is a UV system and the BIOS is compatible with the
kernel's UV apic driver.  This prevents some possibly obscure
panics and guards the system against being started on SGI
hardware that does not have the required kernel support.
Signed-off-by: NMike Travis <travis@sgi.com>
Acked-by: NHedi Berriche <hedi@sgi.com>
Acked-by: NDimitri Sivanich <sivanich@sgi.com>
Link: http://lkml.kernel.org/r/20150409182629.112998930@asylum.americas.sgi.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Optimize the first "SGI" OEM check to return faster if the
system is not an SGI or UV system.
Signed-off-by: NMike Travis <travis@sgi.com>
Acked-by: NHedi Berriche <hedi@sgi.com>
Acked-by: NDimitri Sivanich <sivanich@sgi.com>
Link: http://lkml.kernel.org/r/20150409182628.952357922@asylum.americas.sgi.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Remove the end address checking for flushda function. We need to flush
each address line for flushda instruction, from start to end address.
This is because flushda instruction only flush the cache if tag and line
fields are matched.

Change to use ldwio instruction (bypass cache) to load the instruction
that causing trap. Our interest is the actual instruction that executed
by the processor, this should be uncached.
Note, EA address might be an userspace cached address.
Signed-off-by: NLey Foon Tan <lftan@altera.com>

These are all register available in nios2.
Signed-off-by: NLey Foon Tan <lftan@altera.com>

The comment line regarding IOMMU_INIT and IOMMU_INIT_FINISH
macros is incorrect:

  "The standard vs the _FINISH differs in that the _FINISH variant
  will continue detecting other IOMMUs in the call list..."

It should be "..the *standard* variant will continue
detecting..."

Fix that. Also, make it readable while at it.
Signed-off-by: NAravind Gopalakrishnan <Aravind.Gopalakrishnan@amd.com>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: konrad.wilk@oracle.com
Fixes: 6e963669 ("x86, iommu: Update header comments with appropriate naming")
Link: http://lkml.kernel.org/r/1428508017-5316-1-git-send-email-Aravind.Gopalakrishnan@amd.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

execve stubs are 7 bytes only. Padding them to 16 bytes is a
waste.

   text	   data	    bss	    dec	    hex	filename
  12594	      0	      0	  12594	   3132	entry_64.o.before
  12530	      0	      0	  12530	   30f2	entry_64.o

Run-tested.
Signed-off-by: NDenys Vlasenko <dvlasenk@redhat.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1428439424-7258-8-git-send-email-dvlasenk@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

It used to be used to check for _TIF_IA32, but the check has
been removed.

Remove GET_THREAD_INFO() too.

Run-tested.
Signed-off-by: NDenys Vlasenko <dvlasenk@redhat.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1428439424-7258-7-git-send-email-dvlasenk@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Replace
        test
        jz  1f
        jmp label
    1:

with
        test
        jnz label

Run-tested.
Signed-off-by: NDenys Vlasenko <dvlasenk@redhat.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1428439424-7258-6-git-send-email-dvlasenk@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Jumping to the very next instruction is not very useful:

        jmp label
    label:

Removing the jump.
Signed-off-by: NDenys Vlasenko <dvlasenk@redhat.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1428439424-7258-5-git-send-email-dvlasenk@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Replace "call func; ret" with "jmp func".

Run-tested.
Signed-off-by: NDenys Vlasenko <dvlasenk@redhat.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1428439424-7258-4-git-send-email-dvlasenk@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

The change which affected how execve clears EXTRA_REGS missed
32-bit execve syscalls.

Fix this by using 64-bit execve stub epilogue for them too.

Run-tested.
Signed-off-by: NDenys Vlasenko <dvlasenk@redhat.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1428439424-7258-3-git-send-email-dvlasenk@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

This is a preparatory patch for moving stub32_execve[at]() to this
file. It makes sense to have all execve stubs in one place, so
that they can reuse code.
Signed-off-by: NDenys Vlasenko <dvlasenk@redhat.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1428439424-7258-2-git-send-email-dvlasenk@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Similarly to stub_execve, we can reuse the epilogue in
stub_rt_sigreturn() and stub_x32_rt_sigreturn().

Add a comment explaining why we can't eliminage SAVE_EXTRA_REGS
here.
Signed-off-by: NDenys Vlasenko <dvlasenk@redhat.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1428439424-7258-1-git-send-email-dvlasenk@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Commit 1bc9e47a ("powerpc/jump_label: Use HAVE_JUMP_LABEL")
converted uses of CONFIG_JUMP_LABEL to HAVE_JUMP_LABEL in
some assembly files.

HAVE_JUMP_LABEL is defined in linux/jump_label.h, so we need to
include this or we always get the non jump label fallback code.
Signed-off-by: NAnton Blanchard <anton@samba.org>
Acked-by: NMichael Ellerman <mpe@ellerman.id.au>
Acked-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: benh@kernel.crashing.org
Cc: catalin.marinas@arm.com
Cc: davem@davemloft.net
Cc: heiko.carstens@de.ibm.com
Cc: jbaron@akamai.com
Cc: linux@arm.linux.org.uk
Cc: linuxppc-dev@lists.ozlabs.org
Cc: liuj97@gmail.com
Cc: mgorman@suse.de
Cc: mmarek@suse.cz
Cc: paulus@samba.org
Cc: ralf@linux-mips.org
Cc: rostedt@goodmis.org
Cc: schwidefsky@de.ibm.com
Cc: will.deacon@arm.com
Fixes: 1bc9e47a ("powerpc/jump_label: Use HAVE_JUMP_LABEL")
Link: http://lkml.kernel.org/r/1428551492-21977-3-git-send-email-anton@samba.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>

Wrap asm/jump_label.h for all archs with #ifndef __ASSEMBLY__.
Since these are kernel only headers, we don't need #ifdef
__KERNEL__ so can simplify things a bit.

If an architecture wants to use jump labels in assembly, it
will still need to define a macro to create the __jump_table
entries (see ARCH_STATIC_BRANCH in the powerpc asm/jump_label.h
for an example).
Signed-off-by: NAnton Blanchard <anton@samba.org>
Acked-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: benh@kernel.crashing.org
Cc: catalin.marinas@arm.com
Cc: davem@davemloft.net
Cc: heiko.carstens@de.ibm.com
Cc: jbaron@akamai.com
Cc: linux@arm.linux.org.uk
Cc: linuxppc-dev@lists.ozlabs.org
Cc: liuj97@gmail.com
Cc: mgorman@suse.de
Cc: mmarek@suse.cz
Cc: mpe@ellerman.id.au
Cc: paulus@samba.org
Cc: ralf@linux-mips.org
Cc: rostedt@goodmis.org
Cc: schwidefsky@de.ibm.com
Cc: will.deacon@arm.com
Link: http://lkml.kernel.org/r/1428551492-21977-1-git-send-email-anton@samba.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>

The rule for 'copy_from_user()' is that it zeroes the remaining kernel
buffer even when the copy fails halfway, just to make sure that we don't
leave uninitialized kernel memory around.  Because even if we check for
errors, some kernel buffers stay around after thge copy (think page
cache).

However, the x86-64 logic for user copies uses a copy_user_generic()
function for all the cases, that set the "zerorest" flag for any fault
on the source buffer.  Which meant that it didn't just try to clear the
kernel buffer after a failure in copy_from_user(), it also tried to
clear the destination user buffer for the "copy_in_user()" case.

Not only is that pointless, it also means that the clearing code has to
worry about the tail clearing taking page faults for the user buffer
case.  Which is just stupid, since that case shouldn't happen in the
first place.

Get rid of the whole "zerorest" thing entirely, and instead just check
if the destination is in kernel space or not.  And then just use
memset() to clear the tail of the kernel buffer if necessary.
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This reverts commit d63e2e1f.

David Ahern reported that d63e2e1f breaks booting on an 8-socket T5
sparc system.  He also verified that the system boots with d63e2e1f
reverted.  Yinghai has some fixes, but they need a little more polishing
than we can do before v4.0.

Link: http://lkml.kernel.org/r/5514391F.2030300@oracle.com	# report
Link: http://lkml.kernel.org/r/1427857069-6789-1-git-send-email-yinghai@kernel.org # patches
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
CC: stable@vger.kernel.org	# v3.19+

Dirty logging tracks sptes in 4k granularity, meaning that large sptes
have to be split.  If live migration is successful, the guest in the
source machine will be destroyed and large sptes will be created in the
destination. However, the guest continues to run in the source machine
(for example if live migration fails), small sptes will remain around
and cause bad performance.

This patch introduce lazy collapsing of small sptes into large sptes.
The rmap will be scanned in ioctl context when dirty logging is stopped,
dropping those sptes which can be collapsed into a single large-page spte.
Later page faults will create the large-page sptes.
Reviewed-by: NXiao Guangrong <guangrong.xiao@linux.intel.com>
Signed-off-by: NWanpeng Li <wanpeng.li@linux.intel.com>
Message-Id: <1428046825-6905-1-git-send-email-wanpeng.li@linux.intel.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

CR2 is not cleared as it should after reset.  See Intel SDM table named "IA-32
Processor States Following Power-up, Reset, or INIT".
Signed-off-by: NNadav Amit <namit@cs.technion.ac.il>
Message-Id: <1427933438-12782-5-git-send-email-namit@cs.technion.ac.il>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

DR0-DR3 are not cleared as they should during reset and when they are set from
userspace.  It appears to be caused by c77fb5fe ("KVM: x86: Allow the guest
to run with dirty debug registers").

Force their reload on these situations.
Signed-off-by: NNadav Amit <namit@cs.technion.ac.il>
Message-Id: <1427933438-12782-4-git-send-email-namit@cs.technion.ac.il>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

After reset, the CPU can change the BSP, which will be used upon INIT.  Reset
should return the BSP which QEMU asked for, and therefore handled accordingly.

To quote: "If the MP protocol has completed and a BSP is chosen, subsequent
INITs (either to a specific processor or system wide) do not cause the MP
protocol to be repeated."
[Intel SDM 8.4.2: MP Initialization Protocol Requirements and Restrictions]
Signed-off-by: NNadav Amit <namit@cs.technion.ac.il>
Message-Id: <1427933438-12782-3-git-send-email-namit@cs.technion.ac.il>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

recalculate_apic_map() uses two passes over all VCPUs.  This is a relic
from time when we selected a global mode in the first pass and set up
the optimized table in the second pass (to have a consistent mode).

Recent changes made mixed mode unoptimized and we can do it in one pass.
Format of logical MDA is a function of the mode, so we encode it in
apic_logical_id() and drop obsoleted variables from the struct.
Signed-off-by: NRadim Krčmář <rkrcmar@redhat.com>
Message-Id: <1423766494-26150-5-git-send-email-rkrcmar@redhat.com>
[Add lid_bits temporary in apic_logical_id. - Paolo]
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

We want to support mixed modes and the easiest solution is to avoid
optimizing those weird and unlikely scenarios.
Signed-off-by: NRadim Krčmář <rkrcmar@redhat.com>
Message-Id: <1423766494-26150-4-git-send-email-rkrcmar@redhat.com>
[Add comment above KVM_APIC_MODE_* defines. - Paolo]
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Broadcast allowed only one global APIC mode, but mixed modes are
theoretically possible.  x2APIC IPI doesn't mean 0xff as broadcast,
the rest does.

x2APIC broadcasts are accepted by xAPIC.  If we take SDM to be logical,
even addreses beginning with 0xff should be accepted, but real hardware
disagrees.  This patch aims for simple code by considering most of real
behavior as undefined.
Signed-off-by: NRadim Krčmář <rkrcmar@redhat.com>
Message-Id: <1423766494-26150-3-git-send-email-rkrcmar@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

In mixed modes, we musn't deliver xAPIC IPIs like x2APIC and vice versa.
Instead of preserving the information in apic_send_ipi(), we regain it
by converting all destinations into correct MDA in the slow path.
This allows easier reasoning about subsequent matching.

Our kvm_apic_broadcast() had an interesting design decision: it didn't
consider IOxAPIC 0xff as broadcast in x2APIC mode ...
everything worked because IOxAPIC can't set that in physical mode and
logical mode considered it as a message for first 8 VCPUs.
This patch interprets IOxAPIC 0xff as x2APIC broadcast.
Signed-off-by: NRadim Krčmář <rkrcmar@redhat.com>
Message-Id: <1423766494-26150-2-git-send-email-rkrcmar@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Drop unused static procedure which doesn't have callers within its
translation unit. It had been already removed independently in QEMU[1]
from the OpenPIC implementation borrowed from the kernel.

[1] https://lists.gnu.org/archive/html/qemu-devel/2014-06/msg01812.htmlSigned-off-by: NArseny Solokha <asolokha@kb.kras.ru>
Cc: Alexander Graf <agraf@suse.de>
Cc: Gleb Natapov <gleb@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <1424768706-23150-3-git-send-email-asolokha@kb.kras.ru>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

After speed-up of cpuid_maxphyaddr() it can be called frequently:
instead of heavyweight enumeration of CPUID entries it returns a cached
pre-computed value. It is also inlined now. So caching its result became
unnecessary and can be removed.
Signed-off-by: NEugene Korenevsky <ekorenevsky@gmail.com>
Message-Id: <20150329205644.GA1258@gnote>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

On each VM-entry CPU should check the following VMCS fields for zero bits
beyond physical address width:
-  APIC-access address
-  virtual-APIC address
-  posted-interrupt descriptor address
This patch adds these checks required by Intel SDM.
Signed-off-by: NEugene Korenevsky <ekorenevsky@gmail.com>
Message-Id: <20150329205627.GA1244@gnote>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>