objtool reports the following warning for kretprobe_trampoline():

  arch/x86/kernel/kprobes/core.o: warning: objtool: kretprobe_trampoline()+0x20: call without frame pointer save/setup

kretprobes are a special case where the stack is intentionally wrong.
The return address isn't known at the beginning of the trampoline, so
the stack frame can't be set up properly before it calls
trampoline_handler().

Because kretprobe handlers don't sleep, the frame pointer doesn't *have*
to be accurate in the trampoline.  So it's ok to tell objtool to ignore
it.  This results in no actual changes to the generated code.
Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Bernd Petrovitsch <bernd@petrovitsch.priv.at>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Chris J Arges <chris.j.arges@canonical.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Pedro Alves <palves@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/7eaf37de52456ff822ffc86b928edb5d48a40ef1.1456719558.git.jpoimboe@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

objtool reports the following false positive warning:

  arch/x86/xen/enlighten.o: warning: objtool: xen_cpuid()+0x41: can't find jump dest instruction at .text+0x108

The warning is due to xen_cpuid()'s use of XEN_EMULATE_PREFIX to insert
some fake instructions which objtool doesn't know how to decode.
Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Bernd Petrovitsch <bernd@petrovitsch.priv.at>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Chris J Arges <chris.j.arges@canonical.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Pedro Alves <palves@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/bb88399840406629e3417831dc371ecd2842e2a6.1456719558.git.jpoimboe@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Add a new macro, STACK_FRAME_NON_STANDARD(), which is used to denote a
function which does something unusual related to its stack frame.  Use
of the macro prevents objtool from emitting a false positive warning.
Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Bernd Petrovitsch <bernd@petrovitsch.priv.at>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Chris J Arges <chris.j.arges@canonical.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Pedro Alves <palves@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/34487a17b23dba43c50941599d47054a9584b219.1456719558.git.jpoimboe@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Code which runs outside the kernel's normal mode of operation often does
unusual things which can cause a static analysis tool like objtool to
emit false positive warnings:

 - boot image
 - vdso image
 - relocation
 - realmode
 - efi
 - head
 - purgatory
 - modpost

Set OBJECT_FILES_NON_STANDARD for their related files and directories,
which will tell objtool to skip checking them.  It's ok to skip them
because they don't affect runtime stack traces.

Also skip the following code which does the right thing with respect to
frame pointers, but is too "special" to be validated by a tool:

 - entry
 - mcount

Also skip the test_nx module because it modifies its exception handling
table at runtime, which objtool can't understand.  Fortunately it's
just a test module so it doesn't matter much.

Currently objtool is the only user of OBJECT_FILES_NON_STANDARD, but it
might eventually be useful for other tools.
Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Bernd Petrovitsch <bernd@petrovitsch.priv.at>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Chris J Arges <chris.j.arges@canonical.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Pedro Alves <palves@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/366c080e3844e8a5b6a0327dc7e8c2b90ca3baeb.1456719558.git.jpoimboe@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Previous Commit ("ARC: SMP: No need for CONFIG_ARC_IPI_DBG") removed
the Kconfig option ARC_IPI_DBG.  Remove the last reference on this
option.
Signed-off-by: NValentin Rothberg <valentinrothberg@gmail.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

If __preempt_schedule() or __preempt_schedule_notrace() is referenced at
the beginning of a function, gcc can insert the asm inline "call
___preempt_schedule[_notrace]" instruction before setting up a stack
frame, which breaks frame pointer convention if CONFIG_FRAME_POINTER is
enabled and can result in bad stack traces.

Force a stack frame to be created if CONFIG_FRAME_POINTER is enabled by
listing the stack pointer as an output operand for the inline asm
statements.

Specifically this fixes the following stacktool warnings:

  stacktool: drivers/scsi/hpsa.o: hpsa_scsi_do_simple_cmd.constprop.106()+0x79: call without frame pointer save/setup
  stacktool: fs/mbcache.o: mb_cache_entry_find_first()+0x70: call without frame pointer save/setup
  stacktool: fs/mbcache.o: mb_cache_entry_find_first()+0x92: call without frame pointer save/setup
  stacktool: fs/mbcache.o: mb_cache_entry_free()+0xff: call without frame pointer save/setup
  stacktool: fs/mbcache.o: mb_cache_entry_free()+0xf5: call without frame pointer save/setup
  stacktool: fs/mbcache.o: mb_cache_entry_free()+0x11a: call without frame pointer save/setup
  stacktool: fs/mbcache.o: mb_cache_entry_get()+0x225: call without frame pointer save/setup
  stacktool: kernel/locking/percpu-rwsem.o: percpu_up_read()+0x27: call without frame pointer save/setup
  stacktool: kernel/profile.o: do_profile_hits.isra.5()+0x139: call without frame pointer save/setup
  stacktool: lib/nmi_backtrace.o: nmi_trigger_all_cpu_backtrace()+0x2b6: call without frame pointer save/setup
  stacktool: net/rds/ib_cm.o: rds_ib_cq_comp_handler_recv()+0x58: call without frame pointer save/setup
  stacktool: net/rds/ib_cm.o: rds_ib_cq_comp_handler_send()+0x58: call without frame pointer save/setup
  stacktool: net/rds/ib_recv.o: rds_ib_attempt_ack()+0xc1: call without frame pointer save/setup
  stacktool: net/rds/iw_recv.o: rds_iw_attempt_ack()+0xc1: call without frame pointer save/setup
  stacktool: net/rds/iw_recv.o: rds_iw_recv_cq_comp_handler()+0x55: call without frame pointer save/setup

So it only adds a stack frame to 15 call sites out of ~5000 calls to
___preempt_schedule[_notrace]().  All the others already had stack frames.

Oddly, this change actually seems to make things faster in a lot of
cases.  For many smaller functions it causes the stack frame creation to
get moved out of the common path and into the unlikely path.

For example, here's the original cyc2ns_read_end():

  ffffffff8101f8c0 <cyc2ns_read_end>:
  ffffffff8101f8c0:	55                   	push   %rbp
  ffffffff8101f8c1:	48 89 e5             	mov    %rsp,%rbp
  ffffffff8101f8c4:	83 6f 10 01          	subl   $0x1,0x10(%rdi)
  ffffffff8101f8c8:	75 08                	jne    ffffffff8101f8d2 <cyc2ns_read_end+0x12>
  ffffffff8101f8ca:	65 48 89 3d e6 5a ff 	mov    %rdi,%gs:0x7eff5ae6(%rip)        # 153b8 <cyc2ns+0x38>
  ffffffff8101f8d1:	7e
  ffffffff8101f8d2:	65 ff 0d 77 c4 fe 7e 	decl   %gs:0x7efec477(%rip)        # bd50 <__preempt_count>
  ffffffff8101f8d9:	74 02                	je     ffffffff8101f8dd <cyc2ns_read_end+0x1d>
  ffffffff8101f8db:	5d                   	pop    %rbp
  ffffffff8101f8dc:	c3                   	retq
  ffffffff8101f8dd:	e8 1e 37 fe ff       	callq  ffffffff81003000 <___preempt_schedule>
  ffffffff8101f8e2:	5d                   	pop    %rbp
  ffffffff8101f8e3:	c3                   	retq
  ffffffff8101f8e4:	66 66 66 2e 0f 1f 84 	data16 data16 nopw %cs:0x0(%rax,%rax,1)
  ffffffff8101f8eb:	00 00 00 00 00

And here's the same function with the patch:

  ffffffff8101f8c0 <cyc2ns_read_end>:
  ffffffff8101f8c0:	83 6f 10 01          	subl   $0x1,0x10(%rdi)
  ffffffff8101f8c4:	75 08                	jne    ffffffff8101f8ce <cyc2ns_read_end+0xe>
  ffffffff8101f8c6:	65 48 89 3d ea 5a ff 	mov    %rdi,%gs:0x7eff5aea(%rip)        # 153b8 <cyc2ns+0x38>
  ffffffff8101f8cd:	7e
  ffffffff8101f8ce:	65 ff 0d 7b c4 fe 7e 	decl   %gs:0x7efec47b(%rip)        # bd50 <__preempt_count>
  ffffffff8101f8d5:	74 01                	je     ffffffff8101f8d8 <cyc2ns_read_end+0x18>
  ffffffff8101f8d7:	c3                   	retq
  ffffffff8101f8d8:	55                   	push   %rbp
  ffffffff8101f8d9:	48 89 e5             	mov    %rsp,%rbp
  ffffffff8101f8dc:	e8 1f 37 fe ff       	callq  ffffffff81003000 <___preempt_schedule>
  ffffffff8101f8e1:	5d                   	pop    %rbp
  ffffffff8101f8e2:	c3                   	retq
  ffffffff8101f8e3:	66 66 66 66 2e 0f 1f 	data16 data16 data16 nopw %cs:0x0(%rax,%rax,1)
  ffffffff8101f8ea:	84 00 00 00 00 00

Notice that it moved the frame pointer setup code to the unlikely
___preempt_schedule() call path.  Going through a sampling of the
differences in the asm, that's the most common change I see.

Otherwise it has no real effect on callers which already have stack
frames (though it does result in the reordering of some 'mov's).
Reported-by: NJiri Slaby <jslaby@suse.cz>
Tested-by: NJiri Slaby <jslaby@suse.cz>
Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/20160218174158.GA28230@treble.redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Stacktool generates the following warning:
  stacktool: arch/x86/kvm/vmx.o: vmx_handle_external_intr()+0x67: call without frame pointer save/setup

By adding the stackpointer as an output operand, this patch ensures that a
stack frame is created when CONFIG_FRAME_POINTER is enabled for the inline
assmebly statement.
Signed-off-by: NChris J Arges <chris.j.arges@canonical.com>
Reviewed-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: gleb@kernel.org
Cc: kvm@vger.kernel.org
Cc: live-patching@vger.kernel.org
Cc: pbonzini@redhat.com
Link: http://lkml.kernel.org/r/1453499078-9330-3-git-send-email-chris.j.arges@canonical.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

The assembly PV_UNLOCK function is a callable non-leaf function which
doesn't honor CONFIG_FRAME_POINTER, which can result in bad stack
traces.

Create a stack frame when CONFIG_FRAME_POINTER is enabled.
Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Bernd Petrovitsch <bernd@petrovitsch.priv.at>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Chris J Arges <chris.j.arges@canonical.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: Michal Marek <mmarek@suse.cz>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Pedro Alves <palves@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman Long <Waiman.Long@hpe.com>
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/6685a72ddbbd0ad3694337cca0af4b4ea09f5f40.1453405861.git.jpoimboe@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

With some configs (including allyesconfig), gcc doesn't inline
test_cc().  When that happens, test_cc() doesn't create a stack frame
before inserting the inline asm call instruction.  This breaks frame
pointer convention if CONFIG_FRAME_POINTER is enabled and can result in
a bad stack trace.

Force it to always be inlined so that its containing function's stack
frame can be used.
Suggested-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Acked-by: NPaolo Bonzini <pbonzini@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Bernd Petrovitsch <bernd@petrovitsch.priv.at>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Chris J Arges <chris.j.arges@canonical.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Gleb Natapov <gleb@kernel.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Pedro Alves <palves@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kvm@vger.kernel.org
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/20160122161612.GE20502@treble.redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

The callable functions created with the FOP* and FASTOP* macros are
missing ELF function annotations, which confuses tools like stacktool.
Properly annotate them.

This adds some additional labels to the assembly, but the generated
binary code is unchanged (with the exception of instructions which have
embedded references to __LINE__).
Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Acked-by: NPaolo Bonzini <pbonzini@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Bernd Petrovitsch <bernd@petrovitsch.priv.at>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Chris J Arges <chris.j.arges@canonical.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Gleb Natapov <gleb@kernel.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Pedro Alves <palves@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kvm@vger.kernel.org
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/e399651c89ace54906c203c0557f66ed6ea3ce8d.1453405861.git.jpoimboe@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

The kretprobe_trampoline_holder() wrapper around kretprobe_trampoline()
isn't used anywhere and adds some unnecessary frame pointer instructions
which never execute.  Instead, just make kretprobe_trampoline() a proper
ELF function.
Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Acked-by: NMasami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Bernd Petrovitsch <bernd@petrovitsch.priv.at>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Chris J Arges <chris.j.arges@canonical.com>
Cc: David S. Miller <davem@davemloft.net>
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: Michal Marek <mmarek@suse.cz>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Pedro Alves <palves@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/92d921b102fb865a7c254cfde9e4a0a72b9a781e.1453405861.git.jpoimboe@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

bpf_jit.S has several callable non-leaf functions which don't honor
CONFIG_FRAME_POINTER, which can result in bad stack traces.

Create a stack frame before the call instructions when
CONFIG_FRAME_POINTER is enabled.
Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Bernd Petrovitsch <bernd@petrovitsch.priv.at>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Chris J Arges <chris.j.arges@canonical.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: Michal Marek <mmarek@suse.cz>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Pedro Alves <palves@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: live-patching@vger.kernel.org
Cc: netdev@vger.kernel.org
Link: http://lkml.kernel.org/r/fa4c41976b438b51954cb8021f06bceb1d1d66cc.1453405861.git.jpoimboe@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

bpf_jit.S has several functions which can be called from C code.  Give
them proper ELF annotations.
Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Bernd Petrovitsch <bernd@petrovitsch.priv.at>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Chris J Arges <chris.j.arges@canonical.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: Michal Marek <mmarek@suse.cz>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Pedro Alves <palves@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: live-patching@vger.kernel.org
Cc: netdev@vger.kernel.org
Link: http://lkml.kernel.org/r/bbe1de0c299fecd4fc9a1766bae8be2647bedb01.1453405861.git.jpoimboe@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Numerous 'call without frame pointer save/setup' warnings are introduced
by stacktool because of functions using the get_user() macro. Bad stack
traces could occur due to lack of or misplacement of stack frame setup
code.

This patch forces a stack frame to be created before the inline asm code
if CONFIG_FRAME_POINTER is enabled by listing the stack pointer as an
output operand for the get_user() inline assembly statement.
Signed-off-by: NChris J Arges <chris.j.arges@canonical.com>
Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: NBorislav Petkov <bp@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Bernd Petrovitsch <bernd@petrovitsch.priv.at>
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: Michal Marek <mmarek@suse.cz>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Pedro Alves <palves@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/bc85501f221ee512670797c7f110022e64b12c81.1453405861.git.jpoimboe@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

swsusp_arch_suspend() and restore_registers() are callable non-leaf
functions which don't honor CONFIG_FRAME_POINTER, which can result in
bad stack traces.  Also they aren't annotated as ELF callable functions
which can confuse tooling.

Create a stack frame for them when CONFIG_FRAME_POINTER is enabled and
give them proper ELF function annotations.
Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: NBorislav Petkov <bp@suse.de>
Acked-by: NPavel Machek <pavel@ucw.cz>
Acked-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Bernd Petrovitsch <bernd@petrovitsch.priv.at>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Chris J Arges <chris.j.arges@canonical.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: Michal Marek <mmarek@suse.cz>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Pedro Alves <palves@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/bdad00205897dc707aebe9e9e39757085e2bf999.1453405861.git.jpoimboe@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

efi_call() is a callable non-leaf function which doesn't honor
CONFIG_FRAME_POINTER, which can result in bad stack traces.

Create a stack frame for it when CONFIG_FRAME_POINTER is enabled.
Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: NMatt Fleming <matt@codeblueprint.co.uk>
Reviewed-by: NBorislav Petkov <bp@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Bernd Petrovitsch <bernd@petrovitsch.priv.at>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Chris J Arges <chris.j.arges@canonical.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: Michal Marek <mmarek@suse.cz>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Pedro Alves <palves@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/2294b6fad60eea4cc862eddc8e98a1324e6eeeca.1453405861.git.jpoimboe@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

rwsem.S has several callable non-leaf functions which don't honor
CONFIG_FRAME_POINTER, which can result in bad stack traces.

Create stack frames for them when CONFIG_FRAME_POINTER is enabled.
Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: NBorislav Petkov <bp@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Bernd Petrovitsch <bernd@petrovitsch.priv.at>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Chris J Arges <chris.j.arges@canonical.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: Michal Marek <mmarek@suse.cz>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Pedro Alves <palves@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/ad0932bbead975b15f9578e4f2cf2ee5961eb840.1453405861.git.jpoimboe@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

do_suspend_lowlevel() is a callable non-leaf function which doesn't
honor CONFIG_FRAME_POINTER, which can result in bad stack traces.

Create a stack frame for it when CONFIG_FRAME_POINTER is enabled.
Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: NBorislav Petkov <bp@suse.de>
Acked-by: NPavel Machek <pavel@ucw.cz>
Acked-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Bernd Petrovitsch <bernd@petrovitsch.priv.at>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Chris J Arges <chris.j.arges@canonical.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Len Brown <len.brown@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Pedro Alves <palves@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/7383d87dd40a460e0d757a0793498b9d06a7ee0d.1453405861.git.jpoimboe@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Thunk functions are callable non-leaf functions that don't honor
CONFIG_FRAME_POINTER, which can result in bad stack traces.  Also they
aren't annotated as ELF callable functions which can confuse tooling.

Create stack frames for them when CONFIG_FRAME_POINTER is enabled and
add the ELF function type.
Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: NBorislav Petkov <bp@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Bernd Petrovitsch <bernd@petrovitsch.priv.at>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Chris J Arges <chris.j.arges@canonical.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: Michal Marek <mmarek@suse.cz>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Pedro Alves <palves@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/4373e5bff459b9fd66ce5d45bfcc881a5c202643.1453405861.git.jpoimboe@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

The crypto code has several callable non-leaf functions which don't
honor CONFIG_FRAME_POINTER, which can result in bad stack traces.

Create stack frames for them when CONFIG_FRAME_POINTER is enabled.
Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Bernd Petrovitsch <bernd@petrovitsch.priv.at>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Chris J Arges <chris.j.arges@canonical.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Pedro Alves <palves@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/6c20192bcf1102ae18ae5a242cabf30ce9b29895.1453405861.git.jpoimboe@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

The frame pointer (RBP) is getting clobbered in
sha1_mb_mgr_submit_avx2() before a function call, which can mess up
stack traces.  Use R12 instead.
Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Bernd Petrovitsch <bernd@petrovitsch.priv.at>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Chris J Arges <chris.j.arges@canonical.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: Michal Marek <mmarek@suse.cz>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Pedro Alves <palves@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/15a3eb7ebe68e37755927915f45e4f0bde4d18c5.1453405861.git.jpoimboe@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

sha1_mb_mgr_flush_avx2() and sha1_mb_mgr_submit_avx2() both allocate a
lot of stack space which is never used.  Also, many of the registers
being saved aren't being clobbered so there's no need to save them.
Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Bernd Petrovitsch <bernd@petrovitsch.priv.at>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Chris J Arges <chris.j.arges@canonical.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: Michal Marek <mmarek@suse.cz>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Pedro Alves <palves@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/9402e4d87580d6b2376ed95f67b84bdcce3c830e.1453405861.git.jpoimboe@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

stacktool reports the following warning:

  stacktool: arch/x86/crypto/crc32c-pcl-intel-asm_64.o: crc_pcl()+0x11dd: can't decode instruction

It gets confused when trying to decode jump_table data.  Move jump_table
to the .rodata section which is a more appropriate home for read-only
data.
Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: NBorislav Petkov <bp@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Bernd Petrovitsch <bernd@petrovitsch.priv.at>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Chris J Arges <chris.j.arges@canonical.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Pedro Alves <palves@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/1dbf80c097bb9d89c0cbddc01a815ada690e3b32.1453405861.git.jpoimboe@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

stacktool reports the following warning:

  stacktool: arch/x86/crypto/aesni-intel_asm.o: _aesni_inc_init(): can't find starting instruction

stacktool gets confused when it tries to disassemble the following data
in the .text section:

  .Lbswap_mask:
          .byte 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0

Move it to .rodata which is a more appropriate section for read-only
data.
Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: NBorislav Petkov <bp@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Bernd Petrovitsch <bernd@petrovitsch.priv.at>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Chris J Arges <chris.j.arges@canonical.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Pedro Alves <palves@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/b6a2f3f8bda705143e127c025edb2b53c86e6eb4.1453405861.git.jpoimboe@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

vide() is a callable function, but is missing the ELF function type,
which confuses tools like stacktool.

Properly annotate it to be a callable function.  The generated code is
unchanged.
Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: NBorislav Petkov <bp@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Bernd Petrovitsch <bernd@petrovitsch.priv.at>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Chris J Arges <chris.j.arges@canonical.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: Michal Marek <mmarek@suse.cz>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Pedro Alves <palves@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/a324095f5c9390ff39b15b4562ea1bbeda1a8282.1453405861.git.jpoimboe@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

A function created with the PV_CALLEE_SAVE_REGS_THUNK macro doesn't set
up a new stack frame before the call instruction, which breaks frame
pointer convention if CONFIG_FRAME_POINTER is enabled and can result in
a bad stack trace.  Also, the thunk functions aren't annotated as ELF
callable functions.

Create a stack frame when CONFIG_FRAME_POINTER is enabled and add the
ELF function type.
Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: NBorislav Petkov <bp@suse.de>
Cc: Alok Kataria <akataria@vmware.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Bernd Petrovitsch <bernd@petrovitsch.priv.at>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Chris J Arges <chris.j.arges@canonical.com>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Pedro Alves <palves@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/a2cad74e87c4aba7fd0f54a1af312e66a824a575.1453405861.git.jpoimboe@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

If a PVOP call macro is inlined at the beginning of a function, gcc can
insert the call instruction before setting up a stack frame, which
breaks frame pointer convention if CONFIG_FRAME_POINTER is enabled and
can result in a bad stack trace.

Force a stack frame to be created if CONFIG_FRAME_POINTER is enabled by
listing the stack pointer as an output operand for the PVOP inline asm
statements.
Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: NBorislav Petkov <bp@suse.de>
Cc: Alok Kataria <akataria@vmware.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Bernd Petrovitsch <bernd@petrovitsch.priv.at>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Chris J Arges <chris.j.arges@canonical.com>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Pedro Alves <palves@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/6a13e48c5a8cf2de1aa112ae2d4c0ac194096282.1453405861.git.jpoimboe@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

xen_irq_enable_direct(), xen_restore_fl_direct(), and check_events() are
callable non-leaf functions which don't honor CONFIG_FRAME_POINTER,
which can result in bad stack traces.

Create stack frames for them when CONFIG_FRAME_POINTER is enabled.
Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Bernd Petrovitsch <bernd@petrovitsch.priv.at>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Chris J Arges <chris.j.arges@canonical.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Pedro Alves <palves@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/a8340ad3fc72ba9ed34da9b3af9cdd6f1a896e17.1453405861.git.jpoimboe@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

xen_adjust_exception_frame() is a callable function, but is missing the
ELF function type, which confuses tools like stacktool.

Properly annotate it to be a callable function.  The generated code is
unchanged.
Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Bernd Petrovitsch <bernd@petrovitsch.priv.at>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Chris J Arges <chris.j.arges@canonical.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Pedro Alves <palves@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/b1851bd17a0986472692a7e3a05290d891382cdd.1453405861.git.jpoimboe@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

If a hypercall is inlined at the beginning of a function, gcc can insert
the call instruction before setting up a stack frame, which breaks frame
pointer convention if CONFIG_FRAME_POINTER is enabled and can result in
a bad stack trace.

Force a stack frame to be created if CONFIG_FRAME_POINTER is enabled by
listing the stack pointer as an output operand for the hypercall inline
asm statements.
Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: NDavid Vrabel <david.vrabel@citrix.com>
Reviewed-by: NBorislav Petkov <bp@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Bernd Petrovitsch <bernd@petrovitsch.priv.at>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Chris J Arges <chris.j.arges@canonical.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Pedro Alves <palves@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/c6face5a46713108bded9c4c103637222abc4528.1453405861.git.jpoimboe@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

This was more relevant during SMP bringup.

The warning for bogus msg better be visible always.
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

ARConnect/MCIP IPI sending has a retry-wait loop in case caller had
not seen a previous such interrupt. Turns out that it is not needed at
all. Linux cross core calling allows coalescing multiple IPIs to same
receiver - it is fine as long as there is one.

This logic is built into upper layer already, at a higher level of
abstraction. ipi_send_msg_one() sets the actual msg payload, but it only
calls MCIP IPI sending if msg holder was empty (using
atomic-set-new-and-get-old construct). Thus it is unlikely that the
retry-wait looping was ever getting exercised at all.

Cc: Chuck Jordan <cjordan@synopsys.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

There is no real ARC700 based SMP SoC so remove IPI definition.
EZChip's SMP ARC700 is going to use a different intc and IPI provider
anyways.
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

ARConnect/MCIP Inter-Core-Interrupt module can't send interrupt to
local core. So use core intc capability to trigger software
interrupt to self, using an unsued IRQ #21.

This showed up as csd deadlock with LTP trace_sched on a dual core
system. This test acts as scheduler fuzzer, triggering all sorts of
schedulting activity. Trouble starts with IPI to self, which doesn't get
delivered (effectively lost due to H/w capability), but the msg intended
to be sent remain enqueued in per-cpu @ipi_data.

All subsequent IPIs to this core from other cores get elided due to the
IPI coalescing optimization in ipi_send_msg_one() where a pending msg
implies an IPI already sent and assumes other core is yet to ack it.
After the elided IPI, other core simply goes into csd_lock_wait()
but never comes out as this core never sees the interrupt.

Fixes STAR 9001008624

Cc: Peter Zijlstra <peterz@infradead.org>
Cc: <stable@vger.kernel.org>        [4.2]
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

In commit 11f1a4b9 ("x86: reorganize SMAP handling in user space
accesses") I changed how the stac/clac instructions were generated
around the user space accesses, which then made it possible to do
batched accesses efficiently for user string copies etc.

However, in doing so, I completely spaced out, and didn't even think
about the 32-bit case.  And nobody really even seemed to notice, because
SMAP doesn't even exist until modern Skylake processors, and you'd have
to be crazy to run 32-bit kernels on a modern CPU.

Which brings us to Andy Lutomirski.

He actually tested the 32-bit kernel on new hardware, and noticed that
it doesn't work.  My bad.  The trivial fix is to add the required
uaccess begin/end markers around the raw accesses in <asm/uaccess_32.h>.

I feel a bit bad about this patch, just because that header file really
should be cleaned up to avoid all the duplicated code in it, and this
commit just expands on the problem.  But this just fixes the bug without
any bigger cleanup surgery.
Reported-and-tested-by: NAndy Lutomirski <luto@kernel.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Even though DEVTMPFS is required when our pre-built initramfs
is used it is not the case in general. It is perfectly possible
to use initramfs with device nodes already populated or there
could be other usages, see discussion below for more detials:
http://thread.gmane.org/gmane.comp.embedded.openwrt.devel/37819/focus=37821

This change removes mentioned dependency from arch/arc/Kconfig
updating instead those defconfigs that are usually used with this
kind of pre-build initramfs.

And while at it all touched defconfigs were regenerated via
savedefconfig and some options were removed:
 * USB is selected by other options implicitly
 * VGA_CONSOLE is disableb for ARC since
   031e29b5
 * EXT3_FS automatically selects EXT4_FS
 * MTDxxx and JFFS2_FS make no sense for AXS because
   AXS NAND controller is not upstreamed
 * NET_OSCI_LAN is not in upstream as well
 * ARCPGU_xxx options make no sense because ARC PGU is not yet
   in upstream and when it gets there all config options would
   be taken from devicetree
Signed-off-by: NAlexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

Although we don't expect to take alignment faults on access to normal
memory, misbehaving (i.e. buggy) user code can pass MMIO pointers into
system calls, leading to things like get_user accessing device memory.

Rather than OOPS the kernel, allow any exception fixups to run and
return something like -EFAULT back to userspace. This makes the
behaviour more consistent with userspace, even though applications with
access to device mappings can easily cause other issues if they try
hard enough.
Acked-by: NCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: NEun Taik Lee <eun.taik.lee@samsung.com>
[will: dropped __kprobes annotation and rewrote commit mesage]
Signed-off-by: NWill Deacon <will.deacon@arm.com>

For the same reason as commit 19514fc6 ("arm, kbuild: make "make
install" not depend on vmlinux"), the install targets should never
trigger the rebuild of the kernel.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

Commit 3565fce3 ("mm, x86: get_user_pages() for dax mappings") has
moved up the pte_page(pte) in x86's fast gup_pte_range(), for no
discernible reason: put it back where it belongs, after the pte_flags
check and the pfn_valid cross-check.

That may be the cause of the NULL pointer dereference in
gup_pte_range(), seen when vfio called vaddr_get_pfn() when starting a
qemu-kvm based VM.
Signed-off-by: NHugh Dickins <hughd@google.com>
Reported-by: NMichael Long <Harn-Solo@gmx.de>
Tested-by: NMichael Long <Harn-Solo@gmx.de>
Acked-by: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>