The Intel Software Developer Manual describes bit 24 in the MCG_CAP
MSR:

   MCG_SER_P (software error recovery support present) flag,
   bit 24 — Indicates (when set) that the processor supports
   software error recovery

But only some models with this capability bit set will actually
generate recoverable machine checks.

Check the model name and set a synthetic capability bit. Provide
a command line option to set this bit anyway in case the kernel
doesn't recognise the model name.
Signed-off-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/2e5bfb23c89800a036fb8a45fa97a74bb16bc362.1455732970.git.tony.luck@intel.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

Signed-off-by: Ingo Molnar <mingo@kernel.org>

A kernel page fault oops with the callstack below was observed
when a read syscall was made to a pmem device after a huge amount
(>512GB) of vmalloc ranges was allocated by ioremap() on a x86_64
system:

     BUG: unable to handle kernel paging request at ffff880840000ff8
     IP: vmalloc_fault+0x1be/0x300
     PGD c7f03a067 PUD 0
     Oops: 0000 [#1] SM
     Call Trace:
        __do_page_fault+0x285/0x3e0
        do_page_fault+0x2f/0x80
        ? put_prev_entity+0x35/0x7a0
        page_fault+0x28/0x30
        ? memcpy_erms+0x6/0x10
        ? schedule+0x35/0x80
        ? pmem_rw_bytes+0x6a/0x190 [nd_pmem]
        ? schedule_timeout+0x183/0x240
        btt_log_read+0x63/0x140 [nd_btt]
         :
        ? __symbol_put+0x60/0x60
        ? kernel_read+0x50/0x80
        SyS_finit_module+0xb9/0xf0
        entry_SYSCALL_64_fastpath+0x1a/0xa4

Since v4.1, ioremap() supports large page (pud/pmd) mappings in
x86_64 and PAE.  vmalloc_fault() however assumes that the vmalloc
range is limited to pte mappings.

vmalloc faults do not normally happen in ioremap'd ranges since
ioremap() sets up the kernel page tables, which are shared by
user processes.  pgd_ctor() sets the kernel's PGD entries to
user's during fork().  When allocation of the vmalloc ranges
crosses a 512GB boundary, ioremap() allocates a new pud table
and updates the kernel PGD entry to point it.  If user process's
PGD entry does not have this update yet, a read/write syscall
to the range will cause a vmalloc fault, which hits the Oops
above as it does not handle a large page properly.

Following changes are made to vmalloc_fault().

64-bit:

 - No change for the PGD sync operation as it handles large
   pages already.
 - Add pud_huge() and pmd_huge() to the validation code to
   handle large pages.
 - Change pud_page_vaddr() to pud_pfn() since an ioremap range
   is not directly mapped (while the if-statement still works
   with a bogus addr).
 - Change pmd_page() to pmd_pfn() since an ioremap range is not
   backed by struct page (while the if-statement still works
   with a bogus addr).

32-bit:
 - No change for the sync operation since the index3 PGD entry
   covers the entire vmalloc range, which is always valid.
   (A separate change to sync PGD entry is necessary if this
    memory layout is changed regardless of the page size.)
 - Add pmd_huge() to the validation code to handle large pages.
   This is for completeness since vmalloc_fault() won't happen
   in ioremap'd ranges as its PGD entry is always valid.
Reported-by: Henning Schild <henning.schild@siemens.com>
Signed-off-by: Toshi Kani <toshi.kani@hpe.com>
Acked-by: Borislav Petkov <bp@alien8.de>
Cc: <stable@vger.kernel.org> # 4.1+
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: linux-mm@kvack.org
Cc: linux-nvdimm@lists.01.org
Link: http://lkml.kernel.org/r/1455758214-24623-1-git-send-email-toshi.kani@hpe.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

Signal delivery needs to know the sign of an interrupted syscall's
return value in order to detect -ERESTART variants.  Normally this
works independently of bitness because syscalls internally return
long.  Under ptrace, however, this can break, and syscall_get_error
is supposed to sign-extend regs->ax if needed.

We were clearing TS_COMPAT too early, though, and this prevented
sign extension, which subtly broke syscall restart under ptrace.
Reported-by: Robert O'Callahan <robert@ocallahan.org>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
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: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Shuah Khan <shuahkh@osg.samsung.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org # 4.3.x-
Fixes: c5c46f59 ("x86/entry: Add new, comprehensible entry and exit handlers written in C")
Link: http://lkml.kernel.org/r/cbce3cf545522f64eb37f5478cb59746230db3b5.1455142412.git.luto@kernel.orgSigned-off-by: Ingo Molnar <mingo@kernel.org>

This catches a regression from the compat syscall rework.  The
32-bit variant of this test currently fails.  The issue is that, for
a 32-bit tracer and a 32-bit tracee, GETREGS+SETREGS with no changes
should be a no-op.  It currently isn't a no-op if RAX indicates
signal restart, because the high bits get cleared and the kernel
loses track of the restart state.
Reported-by: Robert O'Callahan <robert@ocallahan.org>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
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: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Shuah Khan <shuahkh@osg.samsung.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/c4040b40b5b4a37ed31375a69b683f753ec6788a.1455142412.git.luto@kernel.orgSigned-off-by: Ingo Molnar <mingo@kernel.org>

I had some obvious typos.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
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: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Robert O'Callahan <robert@ocallahan.org>
Cc: Shuah Khan <shuahkh@osg.samsung.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/e5e6772d4802986cf7df702e646fa24ac14f2204.1455142412.git.luto@kernel.orgSigned-off-by: Ingo Molnar <mingo@kernel.org>

Looks like the HPET spec at intel.com got moved.
It isn't hard to find so drop the link, just mention
the revision assumed.
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Clemens Ladisch <clemens@ladisch.de>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linux-doc@vger.kernel.org
Link: http://lkml.kernel.org/r/1455145462-3877-1-git-send-email-mst@redhat.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

Data corruption issues were observed in tests which initiated
a system crash/reset while accessing BTT devices.  This problem
is reproducible.

The BTT driver calls pmem_rw_bytes() to update data in pmem
devices.  This interface calls __copy_user_nocache(), which
uses non-temporal stores so that the stores to pmem are
persistent.

__copy_user_nocache() uses non-temporal stores when a request
size is 8 bytes or larger (and is aligned by 8 bytes).  The
BTT driver updates the BTT map table, which entry size is
4 bytes.  Therefore, updates to the map table entries remain
cached, and are not written to pmem after a crash.

Change __copy_user_nocache() to use non-temporal store when
a request size is 4 bytes.  The change extends the current
byte-copy path for a less-than-8-bytes request, and does not
add any overhead to the regular path.
Reported-and-tested-by: Micah Parrish <micah.parrish@hpe.com>
Reported-and-tested-by: Brian Boylston <brian.boylston@hpe.com>
Signed-off-by: Toshi Kani <toshi.kani@hpe.com>
Cc: <stable@vger.kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: linux-nvdimm@lists.01.org
Link: http://lkml.kernel.org/r/1455225857-12039-3-git-send-email-toshi.kani@hpe.com
[ Small readability edits. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Add comments to __copy_user_nocache() to clarify its procedures
and alignment requirements.

Also change numeric branch target labels to named local labels.

No code changed:

 arch/x86/lib/copy_user_64.o:

    text    data     bss     dec     hex filename
    1239       0       0    1239     4d7 copy_user_64.o.before
    1239       0       0    1239     4d7 copy_user_64.o.after

 md5:
    58bed94c2db98c1ca9a2d46d0680aaae  copy_user_64.o.before.asm
    58bed94c2db98c1ca9a2d46d0680aaae  copy_user_64.o.after.asm
Signed-off-by: Toshi Kani <toshi.kani@hpe.com>
Cc: <stable@vger.kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: brian.boylston@hpe.com
Cc: dan.j.williams@intel.com
Cc: linux-nvdimm@lists.01.org
Cc: micah.parrish@hpe.com
Cc: ross.zwisler@linux.intel.com
Cc: vishal.l.verma@intel.com
Link: http://lkml.kernel.org/r/1455225857-12039-2-git-send-email-toshi.kani@hpe.com
[ Small readability edits and added object file comparison. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>

In order to keep this file's size sensible and not cause too much
unnecessary churn, make the rule explicit - similar to pci_ids.h - that
only MSRs which are used in multiple compilation units, should get added
to it.
Signed-off-by: Borislav Petkov <bp@suse.de>
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: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: alex.williamson@redhat.com
Cc: gleb@kernel.org
Cc: joro@8bytes.org
Cc: kvm@vger.kernel.org
Cc: sherry.hurwitz@amd.com
Cc: wei@redhat.com
Link: http://lkml.kernel.org/r/1455612202-14414-5-git-send-email-bp@alien8.deSigned-off-by: Ingo Molnar <mingo@kernel.org>

One of ftrace_caller_end and ftrace_return is redundant so unify them.
Rename ftrace_return to ftrace_epilogue to mean that everything after
that label represents, like an afterword, work which happens *after* the
ftrace call, e.g., the function graph tracer for one.

Steve wants this to rather mean "[a]n event which reflects meaningfully
on a recently ended conflict or struggle." I can imagine that ftrace can
be a struggle sometimes.

Anyway, beef up the comment about the code contents and layout before
ftrace_epilogue label.
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Steven Rostedt <rostedt@goodmis.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: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1455612202-14414-4-git-send-email-bp@alien8.deSigned-off-by: Ingo Molnar <mingo@kernel.org>

This tests the two ABI-preserving cases that DOSEMU cares about, and
it also explicitly tests the new UC_SIGCONTEXT_SS and
UC_STRICT_RESTORE_SS flags.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Borislav Petkov <bp@alien8.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Shuah Khan <shuahkh@osg.samsung.com>
Cc: Stas Sergeev <stsp@list.ru>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/f3d08f98541d0bd3030ceb35e05e21f59e30232c.1455664054.git.luto@kernel.orgSigned-off-by: Ingo Molnar <mingo@kernel.org>

This is a second attempt to make the improvements from c6f20629
("x86/signal/64: Fix SS handling for signals delivered to 64-bit
programs"), which was reverted by 51adbfbba5c6 ("x86/signal/64: Add
support for SS in the 64-bit signal context").

This adds two new uc_flags flags.  UC_SIGCONTEXT_SS will be set for
all 64-bit signals (including x32).  It indicates that the saved SS
field is valid and that the kernel supports the new behavior.

The goal is to fix a problems with signal handling in 64-bit tasks:
SS wasn't saved in the 64-bit signal context, making it awkward to
determine what SS was at the time of signal delivery and making it
impossible to return to a non-flat SS (as calling sigreturn clobbers
SS).

This also made it extremely difficult for 64-bit tasks to return to
fully-defined 16-bit contexts, because only the kernel can easily do
espfix64, but sigreturn was unable to set a non-flag SS:ESP.
(DOSEMU has a monstrous hack to partially work around this
limitation.)

If we could go back in time, the correct fix would be to make 64-bit
signals work just like 32-bit signals with respect to SS: save it
in signal context, reset it when delivering a signal, and restore
it in sigreturn.

Unfortunately, doing that (as I tried originally) breaks DOSEMU:
DOSEMU wouldn't reset the signal context's SS when clearing the LDT
and changing the saved CS to 64-bit mode, since it predates the SS
context field existing in the first place.

This patch is a bit more complicated, and it tries to balance a
bunch of goals.  It makes most cases of changing ucontext->ss during
signal handling work as expected.

I do this by special-casing the interesting case.  On sigreturn,
ucontext->ss will be honored by default, unless the ucontext was
created from scratch by an old program and had a 64-bit CS
(unfortunately, CRIU can do this) or was the result of changing a
32-bit signal context to 64-bit without resetting SS (as DOSEMU
does).

For the benefit of new 64-bit software that uses segmentation (new
versions of DOSEMU might), the new behavior can be detected with a
new ucontext flag UC_SIGCONTEXT_SS.

To avoid compilation issues, __pad0 is left as an alias for ss in
ucontext.

The nitty-gritty details are documented in the header file.

This patch also re-enables the sigreturn_64 and ldt_gdt_64 selftests,
as the kernel change allows both of them to pass.
Tested-by: Stas Sergeev <stsp@list.ru>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Borislav Petkov <bp@alien8.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/749149cbfc3e75cd7fcdad69a854b399d792cc6f.1455664054.git.luto@kernel.org
[ Small readability edit. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Signals are always delivered to 64-bit tasks with CS set to a long
mode segment.  In long mode, SS doesn't matter as long as it's a
present writable segment.

If SS starts out invalid (this can happen if the signal was caused
by an IRET fault or was delivered on the way out of set_thread_area
or modify_ldt), then IRET to the signal handler can fail, eventually
killing the task.

The straightforward fix would be to simply reset SS when delivering
a signal.  That breaks DOSEMU, though: 64-bit builds of DOSEMU rely
on SS being set to the faulting SS when signals are delivered.

As a compromise, this patch leaves SS alone so long as it's valid.

The net effect should be that the behavior of successfully delivered
signals is unchanged.  Some signals that would previously have
failed to be delivered will now be delivered successfully.

This has no effect for x32 or 32-bit tasks: their signal handlers
were already called with SS == __USER_DS.

(On Xen, there's a slight hole: if a task sets SS to a writable
 *kernel* data segment, then we will fail to identify it as invalid
 and we'll still kill the task.  If anyone cares, this could be fixed
 with a new paravirt hook.)
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Borislav Petkov <bp@alien8.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stas Sergeev <stsp@list.ru>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/163c6e1eacde41388f3ff4d2fe6769be651d7b6e.1455664054.git.luto@kernel.orgSigned-off-by: Ingo Molnar <mingo@kernel.org>

These fields have a strange history.  This tries to document it.

This borrows from 9a036b93 ("x86/signal/64: Remove 'fs' and 'gs'
from sigcontext"), which was reverted by ed596cde ("Revert x86
sigcontext cleanups").
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Borislav Petkov <bp@alien8.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stas Sergeev <stsp@list.ru>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/baa78f3c84106fa5acbc319377b1850602f5deec.1455664054.git.luto@kernel.orgSigned-off-by: Ingo Molnar <mingo@kernel.org>

Merge tag 'efi-urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/mfleming/efi into x86/urgent

Pull EFI bug fixes from Matt Fleming:

 * Fix bugs in our code that converts ucs2 strings to utf8 where we
   unintentionally drop bits from the original string (Jason Andryuk)

 * Add the efi-pstore variables to the variable whitelist so that
   users can continue to delete them via efivarfs without needing to
   manipulate the immutable flag (Matt Fleming)
Signed-off-by: Ingo Molnar <mingo@kernel.org>

The comparisons should be >= since 0x800 and 0x80 require an additional bit
to store.

For the 3 byte case, the existing shift would drop off 2 more bits than
intended.

For the 2 byte case, there should be 5 bits bits in byte 1, and 6 bits in
byte 2.
Signed-off-by: Jason Andryuk <jandryuk@gmail.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Cc: Peter Jones <pjones@redhat.com>
Cc: Matthew Garrett <mjg59@coreos.com>
Cc: "Lee, Chun-Yi" <jlee@suse.com>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>

Laszlo explains why this is a good idea,

 'This is because the pstore filesystem can be backed by UEFI variables,
  and (for example) a crash might dump the last kilobytes of the dmesg
  into a number of pstore entries, each entry backed by a separate UEFI
  variable in the above GUID namespace, and with a variable name
  according to the above pattern.

  Please see "drivers/firmware/efi/efi-pstore.c".

  While this patch series will not prevent the user from deleting those
  UEFI variables via the pstore filesystem (i.e., deleting a pstore fs
  entry will continue to delete the backing UEFI variable), I think it
  would be nice to preserve the possibility for the sysadmin to delete
  Linux-created UEFI variables that carry portions of the crash log,
  *without* having to mount the pstore filesystem.'

There's also no chance of causing machines to become bricked by
deleting these variables, which is the whole purpose of excluding
things from the whitelist.

Use the LINUX_EFI_CRASH_GUID guid and a wildcard '*' for the match so
that we don't have to update the string in the future if new variable
name formats are created for crash dump variables.
Reported-by: Laszlo Ersek <lersek@redhat.com>
Acked-by: Peter Jones <pjones@redhat.com>
Tested-by: Peter Jones <pjones@redhat.com>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: "Lee, Chun-Yi" <jlee@suse.com>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>

Merge tag 'efi-urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/mfleming/efi into x86/urgent

Pull EFI fixes from Matt Fleming:

 * Prevent accidental deletion of EFI variables through efivarfs that
   may brick machines. We use a whitelist of known-safe variables to
   allow things like installing distributions to work out of the box, and
   instead restrict vendor-specific variable deletion by making
   non-whitelist variables immutable (Peter Jones)
Signed-off-by: Ingo Molnar <mingo@kernel.org>

When GCC cannot do constant folding for this macro, it falls back to
cpu_has(). But static_cpu_has() is optimal and it works at all times
now. So use it and speedup the fallback case.

Before we had this:

  mov    0x99d674(%rip),%rdx        # ffffffff81b0d9f4 <boot_cpu_data+0x34>
  shr    $0x2e,%rdx
  and    $0x1,%edx
  jne    ffffffff811704e9 <do_munmap+0x3f9>

After alternatives patching, it turns into:

		  jmp    0xffffffff81170390
		  nopl   (%rax)
		  ...
		  callq  ffffffff81056e00 <mpx_notify_unmap>
ffffffff81170390: mov    0x170(%r12),%rdi
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1455578358-28347-1-git-send-email-bp@alien8.deSigned-off-by: Ingo Molnar <mingo@kernel.org>

Update the mailing list used for development of support for ARM64
Renesas SoCs.

This is a follow-up for a similar change for other Renesas SoCs and
drivers uses by Renesas SoCs.  The ARM64 SoC entry was not updated in
that patch as it was not yet present in mainline.

The motivation for the mailing list update is that Renesas SoCs are now
much wider than the SH architecture and there is some desire from some
for the linux-sh list to refocus on discussion of the work on the SH
architecture.
Acked-by: Magnus Damm <damm@opensource.se>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull i915 drm fixes from Dave Airlie:
 "Jani sent a bunch of i915 display fixes as my weekend started, but
  hopefully you can fit them in"

* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
  drm/i915: fix error path in intel_setup_gmbus()
  drm/i915/skl: Fix typo in DPLL_CFGCR1 definition
  drm/i915/skl: Don't skip mst encoders in skl_ddi_pll_select()
  drm/i915: Pretend cursor is always on for ILK-style WM calculations (v2)
  drm/i915/dp: reduce missing TPS3 support errors to debug logging
  drm/i915/dp: abstract training pattern selection
  drm/i915/dsi: skip gpio element execution when not supported
  drm/i915/dsi: don't pass arbitrary data to sideband
  drm/i915/dsi: defend gpio table against out of bounds access
  drm/i915/bxt: Don't save/restore eDP panel power during suspend (v3)
  drm/i915: Allow i915_gem_object_get_page() on userptr as well

i915 display fixes mostly.

* tag 'drm-intel-fixes-2016-02-12' of git://anongit.freedesktop.org/drm-intel:
  drm/i915: fix error path in intel_setup_gmbus()
  drm/i915/skl: Fix typo in DPLL_CFGCR1 definition
  drm/i915/skl: Don't skip mst encoders in skl_ddi_pll_select()
  drm/i915: Pretend cursor is always on for ILK-style WM calculations (v2)
  drm/i915/dp: reduce missing TPS3 support errors to debug logging
  drm/i915/dp: abstract training pattern selection
  drm/i915/dsi: skip gpio element execution when not supported
  drm/i915/dsi: don't pass arbitrary data to sideband
  drm/i915/dsi: defend gpio table against out of bounds access
  drm/i915/bxt: Don't save/restore eDP panel power during suspend (v3)
  drm/i915: Allow i915_gem_object_get_page() on userptr as well

Pull char/misc driver fixes from Greg KH:
 "Here are 3 fixes for some reported issues.  Two nvmem driver fixes,
  and one mei fix.  All have been in linux-next just fine"

* tag 'char-misc-4.5-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
  nvmem: qfprom: Specify LE device endianness
  nvmem: core: return error for non word aligned access
  mei: validate request value in client notify request ioctl

Pull driver core fix from Greg KH:
 "Here is one driver core, well klist, fix for 4.5-rc4.

  It fixes a problem found in the scsi device list traversal that
  probably also could be triggered by other subsystems.

  The fix has been in linux-next for a while with no reported problems"

* tag 'driver-core-4.5-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  klist: fix starting point removed bug in klist iterators

Pull tty/serial fixes from Greg KH:
 "Here are a number of small tty and serial driver fixes for 4.5-rc4
  that resolve some reported issues.

  One of them got reverted as it wasn't correct based on testing, and
  all have been in linux-next for a while"

* tag 'tty-4.5-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  Revert "8250: uniphier: allow modular build with 8250 console"
  pty: make sure super_block is still valid in final /dev/tty close
  pty: fix possible use after free of tty->driver_data
  tty: Add support for PCIe WCH382 2S multi-IO card
  serial/omap: mark wait_for_xmitr as __maybe_unused
  serial: omap: Prevent DoS using unprivileged ioctl(TIOCSRS485)
  8250: uniphier: allow modular build with 8250 console
  tty: Drop krefs for interrupted tty lock

Pull PHY fixes from Greg KH:
 "Here are a couple of PHY driver fixes for 4.5-rc4.

  A few small phy issues.  All have been in linux-next with no reported
  issues"

* tag 'usb-4.5-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
  phy: twl4030-usb: Fix unbalanced pm_runtime_enable on module reload
  phy: twl4030-usb: Relase usb phy on unload
  phy: core: fix wrong err handle for phy_power_on
  phy: Restrict phy-hi6220-usb to HiSilicon arm64

Pull perf tooling fixes from Thomas Gleixner:
 "Another round of fixes for the perf tooling side:

   - Prevent a NULL pointer dereference in tracepoint error handling

   - Fix a thread handling bug in the intel_pt error handling code

   - Search both .eh_frame and .debug_frame sections as toolchains seem
     to have random choices of storing the CFI information

   - Fix the perf state interval output values, which got broken when
     fixing the overall output"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf stat: Fix interval output values
  perf probe: Search both .eh_frame and .debug_frame sections for probe location
  perf tools: Fix thread lifetime related segfaut in intel_pt
  perf tools: tracepoint_error() can receive e=NULL, robustify it

Pull lockdep fix from Thomas Gleixner:
 "A single fix for the stack trace caching logic in lockdep, where the
  duplicate avoidance managed to store no back trace at all"

* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  locking/lockdep: Fix stack trace caching logic

Pull timer fix from Thomas Gleixner:
 "A single fix preventing a 32bit overflow in timespec/val to cputime
  conversions on 32bit machines"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  cputime: Prevent 32bit overflow in time[val|spec]_to_cputime()

Pull irqchip fixes from Thomas Gleixner:
 "Another set of ARM SoC related irqchip fixes:
   - Plug a memory leak in gicv3-its
   - Limit features to the root gic interrupt controller
   - Add a missing barrier in the gic-v3 IAR access
   - Another compile test fix for sun4i"

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqchip/gic-v3: Make sure read from ICC_IAR1_EL1 is visible on redestributor
  irqchip/gic: Only set the EOImodeNS bit for the root controller
  irqchip/gic: Only populate set_affinity for the root controller
  irqchip/gicv3-its: Fix memory leak in its_free_tables()
  irqchip/sun4i: Fix compilation outside of arch/arm

Pull x86 fixes from Thomas Gleixner:
 "Two small fixlets for x86:

   - Prevent a KASAN false positive in thread_saved_pc()

   - Fix a 32-bit truncation problem in the x86 numa code"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm/numa: Fix 32-bit memblock range truncation bug on 32-bit NUMA kernels
  x86: Fix KASAN false positives in thread_saved_pc()

Pull MIPS fixes from Ralf Baechle:
 "Here's the first round of MIPS fixes after the merge window:

   - Detect Octeon III's PCI correctly.
   - Fix return value of the MT7620 probing function.
   - Wire up the copy_file_range syscall.
   - Fix 64k page support on 32 bit kernels.
   - Fix the early Coherency Manager probe.
   - Allow only hardware-supported page sizes to be selected for R6000.
   - Fix corner cases for the RDHWR nstruction emulation on old hardware.
   - Fix FPU handling corner cases.
   - Remove stale entry for BCM33xx from the MAINTAINERS file.
   - 32 and 64 bit ELF headers are different, handle them correctly"

* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus:
  mips: Differentiate between 32 and 64 bit ELF header
  MIPS: Octeon: Update OCTEON_FEATURE_PCIE for Octeon III
  MIPS: pci-mt7620: Fix return value check in mt7620_pci_probe()
  MIPS: Fix early CM probing
  MIPS: Wire up copy_file_range syscall.
  MIPS: Fix 64k page support for 32 bit kernels.
  MIPS: R6000: Don't allow 64k pages for R6000.
  MIPS: traps.c: Correct microMIPS RDHWR emulation
  MIPS: traps.c: Don't emulate RDHWR in the CpU #0 exception handler
  MAINTAINERS: Remove stale entry for BCM33xx chips
  MIPS: Fix FPU disable with preemption
  MIPS: Properly disable FPU in start_thread()
  MIPS: Fix buffer overflow in syscall_get_arguments()

Pull ARM fixes from Russell King:
 "A couple of ARM fixes from Linus for the ICST clock generator code"

[ "Linus" here is Linus Walleij.  Name-stealer.

       Linus "there can be only one" Torvalds ]

* 'fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-arm:
  ARM: 8519/1: ICST: try other dividends than 1
  ARM: 8517/1: ICST: avoid arithmetic overflow in icst_hz()

Pull component helper fixes from Russell King:
 "A few fixes for problems people have encountered with the recent
  update to the component helpers"

* 'component' of git://ftp.arm.linux.org.uk/~rmk/linux-arm:
  component: remove device from master match list on failed add
  component: Detach components when deleting master struct
  component: fix crash on x86_64 with hda audio drivers

Pull more rdma fixes from Doug Ledford:
 "I think we are getting pretty close to done now.  There are four
  one-off fixes in this update:

   - fix ipoib multicast joins
   - fix mlx4 error handling
   - fix mlx5 size computation
   - fix a thinko in core code"

* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dledford/rdma:
  IB/mlx5: Fix RC transport send queue overhead computation
  IB/ipoib: fix for rare multicast join race condition
  IB/core: Fix reading capability mask of the port info class
  net/mlx4: fix some error handling in mlx4_multi_func_init()

Pull SCSI target fixes from Nicholas Bellinger:
 "This includes the long awaited series to address a set of bugs around
  active I/O remote-port LUN_RESET, as well as properly handling this
  same case with concurrent fabric driver session disconnect ->
  reconnect.

  Note this set of LUN_RESET bug-fixes has been surviving extended
  testing on both v4.5-rc1 and v3.14.y code over the last weeks, and is
  CC'ed for stable as it's something folks using multiple ESX connected
  hosts with slow backends can certainly trigger.

  The highlights also include:

   - Fix WRITE_SAME/DISCARD emulation 4k sector conversion in
     target/iblock (Mike Christie)

   - Fix TMR abort interaction and AIO type TMR response in qla2xxx
     target (Quinn Tran + Swapnil Nagle)

   - Fix >= v3.17 stale descriptor pointer regression in qla2xxx target
     (Quinn Tran)

   - Fix >= v4.5-rc1 return regression with unmap_zeros_data_store new
     configfs store handler (nab)

   - Add CPU affinity flag + convert qla2xxx to use bit (Quinn + HCH +
     Bart)"

* git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending:
  qla2xxx: use TARGET_SCF_USE_CPUID flag to indiate CPU Affinity
  target/transport: add flag to indicate CPU Affinity is observed
  target: Fix incorrect unmap_zeroes_data_store return
  qla2xxx: Use ATIO type to send correct tmr response
  qla2xxx: Fix stale pointer access.
  target/user: Fix cast from pointer to phys_addr_t
  target: Drop legacy se_cmd->task_stop_comp + REQUEST_STOP usage
  target: Fix race with SCF_SEND_DELAYED_TAS handling
  target: Fix remote-port TMR ABORT + se_cmd fabric stop
  target: Fix TAS handling for multi-session se_node_acls
  target: Fix LUN_RESET active TMR descriptor handling
  target: Fix LUN_RESET active I/O handling for ACK_KREF
  qla2xxx: Fix TMR ABORT interaction issue between qla2xxx and TCM
  qla2xxx: Fix warning reported by static checker
  target: Fix WRITE_SAME/DISCARD conversion to linux 512b sectors

Pull thermal management fixes from Eduardo Valentin:
 "Specifics in this pull request:

   - Compilation fixes on SPEAR, and U8500 thermal drivers.
   - RCAR thermal driver now recognizes OF-thermal based thermal zones.
   - Small code rework on OF-thermal.
   - These change have been CI tested using KernelCI bot [1,2].  \o/

  I am taking over on Rui's behalf while he is out.  Happy New Chinese
  Year!

  [1] - https://kernelci.org/build/evalenti/kernel/v4.5-rc3-16-ga53b8394ec3c/
  [2] - https://kernelci.org/boot/all/job/evalenti/kernel/v4.5-rc3-16-ga53b8394ec3c/"

* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/evalenti/linux-soc-thermal:
  thermal: cpu_cooling: fix out of bounds access in time_in_idle
  thermal: allow u8500-thermal driver to be a module
  thermal: allow spear-thermal driver to be a module
  thermal: spear: use __maybe_unused for PM functions
  thermal: rcar: enable to use thermal-zone on DT
  thermal: of: use for_each_available_child_of_node for child iterator

Pull another sound fix from Takashi Iwai:
 "This contains a fix for the double-free of usb-audio MIDI device at
  probe failure"

* tag 'sound-fix-4.5-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
  ALSA: usb-audio: avoid freeing umidi object twice