Clang resolves __builtin_constant_p() to false even if the expression is
constant in the end.  The only purpose of that expression was to
differentiate a case where the following expression couldn't be checked
at compile-time, so we can just remove the check.

Clang handles the following two correctly.  Turn it into BUG_ON if there
are any more problems with this.

Fixes: d6321d49 ("KVM: x86: generalize guest_cpuid_has_ helpers")
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>

When user space sets kvm_run->immediate_exit, KVM is supposed to
return quickly. However, when a vCPU is in KVM_MP_STATE_UNINITIALIZED,
the value is not considered and the vCPU blocks.

Fix that oversight.

Fixes: 460df4c1 ("KVM: race-free exit from KVM_RUN without POSIX signals")
Signed-off-by: Jan H. Schönherr <jschoenh@amazon.de>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>

KVM API says that KVM_RUN will return with -EINTR when a signal is
pending. However, if a vCPU is in KVM_MP_STATE_UNINITIALIZED, then
the return value is unconditionally -EAGAIN.

Copy over some code from vcpu_run(), so that the case of a pending
signal results in the expected return value.

Signed-off-by: Jan H. Schönherr <jschoenh@amazon.de>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>

Signed-off-by: Jan H. Schönherr <jschoenh@amazon.de>
Fixes: f6511935 ("KVM: SVM: Add checks for IO instructions")
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>

The commit

	9dd21e104bc ('KVM: x86: simplify handling of PKRU')

removed all users and providers of that call-back, but
didn't remove it. Remove it now.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>

While debugging a problem, I thought that using
cr4_set_bits_and_update_boot() to restore CR4.PCIDE would be
helpful.  It turns out to be counterproductive.

Add a comment documenting how this works.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

When Linux brings a CPU down and back up, it switches to init_mm and then
loads swapper_pg_dir into CR3.  With PCID enabled, this has the side effect
of masking off the ASID bits in CR3.

This can result in some confusion in the TLB handling code.  If we
bring a CPU down and back up with any ASID other than 0, we end up
with the wrong ASID active on the CPU after resume.  This could
cause our internal state to become corrupt, although major
corruption is unlikely because init_mm doesn't have any user pages.
More obviously, if CONFIG_DEBUG_VM=y, we'll trip over an assertion
in the next context switch.  The result of *that* is a failure to
resume from suspend with probability 1 - 1/6^(cpus-1).

Fix it by reinitializing cpu_tlbstate on resume and CPU bringup.

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Reported-by: Jiri Kosina <jikos@kernel.org>
Fixes: 10af6235 ("x86/mm: Implement PCID based optimization: try to preserve old TLB entries using PCID")
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Introduce MADV_WIPEONFORK semantics, which result in a VMA being empty
in the child process after fork.  This differs from MADV_DONTFORK in one
important way.

If a child process accesses memory that was MADV_WIPEONFORK, it will get
zeroes.  The address ranges are still valid, they are just empty.

If a child process accesses memory that was MADV_DONTFORK, it will get a
segmentation fault, since those address ranges are no longer valid in
the child after fork.

Since MADV_DONTFORK also seems to be used to allow very large programs
to fork in systems with strict memory overcommit restrictions, changing
the semantics of MADV_DONTFORK might break existing programs.

MADV_WIPEONFORK only works on private, anonymous VMAs.

The use case is libraries that store or cache information, and want to
know that they need to regenerate it in the child process after fork.

Examples of this would be:
 - systemd/pulseaudio API checks (fail after fork) (replacing a getpid
   check, which is too slow without a PID cache)
 - PKCS#11 API reinitialization check (mandated by specification)
 - glibc's upcoming PRNG (reseed after fork)
 - OpenSSL PRNG (reseed after fork)

The security benefits of a forking server having a re-inialized PRNG in
every child process are pretty obvious.  However, due to libraries
having all kinds of internal state, and programs getting compiled with
many different versions of each library, it is unreasonable to expect
calling programs to re-initialize everything manually after fork.

A further complication is the proliferation of clone flags, programs
bypassing glibc's functions to call clone directly, and programs calling
unshare, causing the glibc pthread_atfork hook to not get called.

It would be better to have the kernel take care of this automatically.

The patch also adds MADV_KEEPONFORK, to undo the effects of a prior
MADV_WIPEONFORK.

This is similar to the OpenBSD minherit syscall with MAP_INHERIT_ZERO:

    https://man.openbsd.org/minherit.2

[akpm@linux-foundation.org: numerically order arch/parisc/include/uapi/asm/mman.h #defines]
Link: http://lkml.kernel.org/r/20170811212829.29186-3-riel@redhat.com


Signed-off-by: Rik van Riel <riel@redhat.com>
Reported-by: Florian Weimer <fweimer@redhat.com>
Reported-by: Colm MacCártaigh <colm@allcosts.net>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Kees Cook <keescook@chromium.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Drewry <wad@chromium.org>
Cc: <linux-api@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Patch series "mm,fork,security: introduce MADV_WIPEONFORK", v4.

If a child process accesses memory that was MADV_WIPEONFORK, it will get
zeroes.  The address ranges are still valid, they are just empty.

If a child process accesses memory that was MADV_DONTFORK, it will get a
segmentation fault, since those address ranges are no longer valid in
the child after fork.

Since MADV_DONTFORK also seems to be used to allow very large programs
to fork in systems with strict memory overcommit restrictions, changing
the semantics of MADV_DONTFORK might break existing programs.

The use case is libraries that store or cache information, and want to
know that they need to regenerate it in the child process after fork.

Examples of this would be:
 - systemd/pulseaudio API checks (fail after fork) (replacing a getpid
   check, which is too slow without a PID cache)
 - PKCS#11 API reinitialization check (mandated by specification)
 - glibc's upcoming PRNG (reseed after fork)
 - OpenSSL PRNG (reseed after fork)

The security benefits of a forking server having a re-inialized PRNG in
every child process are pretty obvious.  However, due to libraries
having all kinds of internal state, and programs getting compiled with
many different versions of each library, it is unreasonable to expect
calling programs to re-initialize everything manually after fork.

A further complication is the proliferation of clone flags, programs
bypassing glibc's functions to call clone directly, and programs calling
unshare, causing the glibc pthread_atfork hook to not get called.

It would be better to have the kernel take care of this automatically.

The patchset also adds MADV_KEEPONFORK, to undo the effects of a prior
MADV_WIPEONFORK.

This is similar to the OpenBSD minherit syscall with MAP_INHERIT_ZERO:

    https://man.openbsd.org/minherit.2

This patch (of 2):

MPX only seems to be available on 64 bit CPUs, starting with Skylake and
Goldmont.  Move VM_MPX into the 64 bit only portion of vma->vm_flags, in
order to free up a VMA flag.

Link: http://lkml.kernel.org/r/20170811212829.29186-2-riel@redhat.com


Signed-off-by: Rik van Riel <riel@redhat.com>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Will Drewry <wad@chromium.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Colm MacCártaigh <colm@allcosts.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

A non-default huge page size can be encoded in the flags argument of the
mmap system call.  The definitions for these encodings are in arch
specific header files.  However, all architectures use the same values.

Consolidate all the definitions in the primary user header file
(uapi/linux/mman.h).  Include definitions for all known huge page sizes.
Use the generic encoding definitions in hugetlb_encode.h as the basis
for these definitions.

Link: http://lkml.kernel.org/r/1501527386-10736-3-git-send-email-mike.kravetz@oracle.com


Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Commit a7be6e5a ("mm: drop useless local parameters of
__register_one_node()") removes the last user of parent_node().

The parent_node() macro in METAG architecture is unnecessary.

Remove it for cleanup.

Link: http://lkml.kernel.org/r/1501076076-1974-4-git-send-email-douly.fnst@cn.fujitsu.com


Signed-off-by: Dou Liyang <douly.fnst@cn.fujitsu.com>
Reported-by: Michael Ellerman <mpe@ellerman.id.au>
Cc: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

As we are about to access the APRs from the GICv2 uaccess interface,
make this logic generally available.

Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <cdall@linaro.org>

The ARM-ARM has two bits in the ESR/HSR relevant to external aborts.
A range of {I,D}FSC values (of which bit 5 is always set) and bit 9 'EA'
which provides:
> an IMPLEMENTATION DEFINED classification of External Aborts.

This bit is in addition to the {I,D}FSC range, and has an implementation
defined meaning. KVM should always ignore this bit when handling external
aborts from a guest.

Remove the ESR_ELx_EA definition and rewrite its helper
kvm_vcpu_dabt_isextabt() to check the {I,D}FSC range. This merges
kvm_vcpu_dabt_isextabt() and the recently added is_abort_sea() helper.

CC: Tyler Baicar <tbaicar@codeaurora.org>
Reported-by: gengdongjiu <gengdj.1984@gmail.com>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <cdall@linaro.org>

Commit 00fc0e0d ("alpha: move exports to actual definitions") also
removed the exports of the math emulator hooks, which are defined in C
code.  In case anyone cares about the option of CONFIG_MATHEMU=m, add
exports next to those definitions.  Also add a MODULE_LICENSE.

Fixes: 00fc0e0d ("alpha: move exports to actual definitions")
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Matt Turner <mattst88@gmail.com>

Add <asm/asm-prototypes.h> so that genksyms knows the types of
these symbols and can generate CRCs for them.

Fixes: 00fc0e0d ("alpha: move exports to actual definitions")
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Matt Turner <mattst88@gmail.com>

Remove old, dead Kconfig options (in order appearing in this commit):
 - IP_NF_QUEUE: commit 3dd6664f ("netfilter: remove unused "config
   IP_NF_QUEUE"");
 - AUTOFS_FS: commit 561c5cf9 ("staging: Remove autofs3");

Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Matt Turner <mattst88@gmail.com>

Use kobj_to_dev() instead of open-coding it.

Signed-off-by: Geliang Tang <geliangtang@163.com>
Signed-off-by: Matt Turner <mattst88@gmail.com>

Remove unneeded variables and assignments.

While we are here, fix the coding style of SMC37c669_read_config():
  - replace whitespaces at the start of lines with tabs
  - remove unneeded whitespaces around parentheses

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Matt Turner <mattst88@gmail.com>

Replace explicit computation of vma page count by a call to
vma_pages()

Signed-off-by: Shyam Saini <mayhs11saini@gmail.com>
Signed-off-by: Matt Turner <mattst88@gmail.com>

We check that "member" is in bounds for the first line, but we also use
it on the next line without checking which is a mistake.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Matt Turner <mattst88@gmail.com>

The alpha/marvel code currently implements an irq_chip for handling
interrupts; due to how irq_chip handling is done, it's necessary for the
irq_chip methods to be invoked from hardirq context, even on a a
real-time kernel.  Because the spinlock_t type becomes a "sleeping"
spinlock w/ RT kernels, it is not suitable to be used with irq_chips.

A quick audit of the operations under the lock reveal that they do only
minimal, bounded work, and are therefore safe to do under a raw spinlock.

Signed-off-by: Julia Cartwright <julia@ni.com>
Signed-off-by: Matt Turner <mattst88@gmail.com>

__NR_sys_epoll_create and friends are alpha-specific
while __NR_epoll_create is a generic name for other
arches.

Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: linux-alpha@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Sergei Trofimovich <slyfox@gentoo.org>
Signed-off-by: Matt Turner <mattst88@gmail.com>

The arch uses a verbatim copy of the asm-generic version and does not
add any own implemntations to the header, so use asm-generic/fb.h
instead of duplicating code.

Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Matt Turner <mattst88@gmail.com>

include/linux/i2c is not for client devices. Move the header file to a
more appropriate location.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Mark Brown <broonie@kernel.org>
Acked-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Acked-by: Kishon Vijay Abraham I <kishon@ti.com>
Acked-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Acked-by: Thierry Reding <thierry.reding@gmail.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

This patch removes CONFIG_NETFILTER_DEBUG and _ASSERT() macros as they
are no longer required. Replace _ASSERT() macros with WARN_ON().

Signed-off-by: Varsha Rao <rvarsha016@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

xive_spapr_init() is called from a __init routine and calls __init
routines.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Commit 350779a2 ("powerpc: Handle most loads and stores in
instruction emulation code", 2017-08-30) changed the register usage
in get_vr and put_vr with the aim of leaving the register number in
r3 untouched on return.  Unfortunately, r6 was not a good choice, as
the callers as of 350779a2 store a MSR value in r6.  Then, in
commit c22435a5 ("powerpc: Emulate FP/vector/VSX loads/stores
correctly when regs not live", 2017-08-30), the saving and restoring
of the MSR got moved into get_vr and put_vr.  Either way, the effect
is that we put a value in MSR that only has the 0x3f8 bits non-zero,
meaning that we are switching to 32-bit mode.  That leads to a crash
like this:

Unable to handle kernel paging request for instruction fetch
Faulting instruction address: 0x0007bea0
Oops: Kernel access of bad area, sig: 11 [#12]
LE SMP NR_CPUS=2048 NUMA PowerNV
Modules linked in: vmx_crypto binfmt_misc ip_tables x_tables autofs4 crc32c_vpmsum
CPU: 6 PID: 32659 Comm: trashy_testcase Tainted: G      D         4.13.0-rc2-00313-gf3026f57e6ed-dirty #23
task: c000000f1bb9e780 task.stack: c000000f1ba98000
NIP:  000000000007bea0 LR: c00000000007b054 CTR: c00000000007be70
REGS: c000000f1ba9b960 TRAP: 0400   Tainted: G      D          (4.13.0-rc2-00313-gf3026f57e6ed-dirty)
MSR:  10000000400010a1 <HV,ME,IR,LE>  CR: 48000228  XER: 00000000
CFAR: c00000000007be74 SOFTE: 1
GPR00: c00000000007b054 c000000f1ba9bbe0 c000000000e6e000 000000000000001d
GPR04: c000000f1ba9bc00 c00000000007be70 00000000000000e8 9000000002009033
GPR08: 0000000002000000 100000000282f033 000000000b0a0900 0000000000001009
GPR12: 0000000000000000 c00000000fd42100 0706050303020100 a5a5a5a5a5a5a5a5
GPR16: 2e2e2e2e2e2de70c 2e2e2e2e2e2e2e2d 0000000000ff00ff 0606040202020000
GPR20: 000000000000005b ffffffffffffffff 0000000003020100 0000000000000000
GPR24: c000000f1ab90020 c000000f1ba9bc00 0000000000000001 0000000000000001
GPR28: c000000f1ba9bc90 c000000f1ba9bea0 000000000b0a0908 0000000000000001
NIP [000000000007bea0] 0x7bea0
LR [c00000000007b054] emulate_loadstore+0x1044/0x1280
Call Trace:
[c000000f1ba9bbe0] [c000000000076b80] analyse_instr+0x60/0x34f0 (unreliable)
[c000000f1ba9bc70] [c00000000007b7ec] emulate_step+0x23c/0x544
[c000000f1ba9bce0] [c000000000053424] arch_uprobe_skip_sstep+0x24/0x40
[c000000f1ba9bd00] [c00000000024b2f8] uprobe_notify_resume+0x598/0xba0
[c000000f1ba9be00] [c00000000001c284] do_notify_resume+0xd4/0xf0
[c000000f1ba9be30] [c00000000000bd44] ret_from_except_lite+0x70/0x74
Instruction dump:
XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX
XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX
---[ end trace a7ae7a7f3e0256b5 ]---

To fix this, we just revert to using r3 as before, since the callers
don't rely on r3 being left unmodified.

Fortunately, this can't be triggered by a misaligned load or store,
because vector loads and stores truncate misaligned addresses rather
than taking an alignment interrupt.  It can be triggered using
uprobes.

Fixes: 350779a2 ("powerpc: Handle most loads and stores in instruction emulation code")
Reported-by: Anton Blanchard <anton@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Tested-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Having the CPU identifier in the debug logs is helpful when tracking
issues. Also add some more logging and fix a compile issue in
xive_do_source_eoi().

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

On POWER9, the Client Architecture Support (CAS) negotiation process
determines whether the guest operates in XIVE Legacy compatibility or
in XIVE exploitation mode. Now that we have initial guest support for
the XIVE interrupt controller, let's inform the hypervisor what we can
do.

The platform advertises the XIVE Exploitation Mode support using the
property "ibm,arch-vec-5-platform-support-vec-5", byte 23 bits 0-1 :

 - 0b00 XIVE legacy mode Only
 - 0b01 XIVE exploitation mode Only
 - 0b10 XIVE legacy or exploitation mode

The OS asks for XIVE Exploitation Mode support using the property
"ibm,architecture-vec-5", byte 23 bits 0-1:

 - 0b00 XIVE legacy mode Only
 - 0b01 XIVE exploitation mode Only

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

The H_INT_ESB hcall() is used to issue a load or store to the ESB page
instead of using the MMIO pages. This can be used as a workaround on
some HW issues. The OS knows that this hcall should be used on an
interrupt source when the ESB hcall flag is set to 1 in the hcall
H_INT_GET_SOURCE_INFO.

To maintain the frontier between the xive frontend and backend, we
introduce a new xive operation 'esb_rw' to be used in the routines
doing memory accesses on the ESBs.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

It will be required later by the H_INT_ESB hcall.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Some source support MMIO stores on the ESB page to perform EOI. Let's
introduce a specific routine for this case even if this should be the
only use of it.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

xive_poke_esb() is performing a load/read so it is better named as
xive_esb_read() as we will need to introduce a xive_esb_write()
routine. Also use the XIVE_ESB_LOAD_EOI offset when EOI'ing LSI
interrupts.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

This is the framework for using XIVE in a PowerVM guest. The support
is very similar to the native one in a much simpler form.

Each source is associated with an Event State Buffer (ESB). This is a
two bit state machine which is used to trigger events. The bits are
named "P" (pending) and "Q" (queued) and can be controlled by MMIO.
The Guest OS registers event (or notifications) queues on which the HW
will post event data for a target to notify.

Instead of OPAL calls, a set of Hypervisors call are used to configure
the interrupt sources and the event/notification queues of the guest:

 - H_INT_GET_SOURCE_INFO

   used to obtain the address of the MMIO page of the Event State
   Buffer (PQ bits) entry associated with the source.

 - H_INT_SET_SOURCE_CONFIG

   assigns a source to a "target".

 - H_INT_GET_SOURCE_CONFIG

   determines to which "target" and "priority" is assigned to a source

 - H_INT_GET_QUEUE_INFO

   returns the address of the notification management page associated
   with the specified "target" and "priority".

 - H_INT_SET_QUEUE_CONFIG

   sets or resets the event queue for a given "target" and "priority".
   It is also used to set the notification config associated with the
   queue, only unconditional notification for the moment.  Reset is
   performed with a queue size of 0 and queueing is disabled in that
   case.

 - H_INT_GET_QUEUE_CONFIG

   returns the queue settings for a given "target" and "priority".

 - H_INT_RESET

   resets all of the partition's interrupt exploitation structures to
   their initial state, losing all configuration set via the hcalls
   H_INT_SET_SOURCE_CONFIG and H_INT_SET_QUEUE_CONFIG.

 - H_INT_SYNC

   issue a synchronisation on a source to make sure sure all
   notifications have reached their queue.

As for XICS, the XIVE interface for the guest is described in the
device tree under the "interrupt-controller" node. A couple of new
properties are specific to XIVE :

 - "reg"

   contains the base address and size of the thread interrupt
   managnement areas (TIMA), also called rings, for the User level and
   for the Guest OS level. Only the Guest OS level is taken into
   account today.

 - "ibm,xive-eq-sizes"

   the size of the event queues. One cell per size supported, contains
   log2 of size, in ascending order.

 - "ibm,xive-lisn-ranges"

   the interrupt numbers ranges assigned to the guest. These are
   allocated using a simple bitmap.

and also :

 - "/ibm,plat-res-int-priorities"

   contains a list of priorities that the hypervisor has reserved for
   its own use.

Tested with a QEMU XIVE model for pseries and with the Power hypervisor.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

This routine will be used in the spapr backend. Also introduce a short
xive_alloc_order() helper.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Older compilers think val may be used uninitialized:

  arch/powerpc/lib/sstep.c: In function 'emulate_loadstore':
  arch/powerpc/lib/sstep.c:2758:23: error: 'val' may be used uninitialized in this function

We know better, but initialise val to 0 to avoid breaking the build.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Andrei Vagin reported a CRIU regression and bisected it back to:

  90f6225f ("x86/idt: Move IST stack based traps to table init")

This table init conversion loses the system-gate property of X86_TRAP_BP
and erroneously moves it from DPL3 to DPL0.

Fix it.

Reported-by: Andrei Vagin <avagin@virtuozzo.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: dvlasenk@redhat.com
Cc: linux-tip-commits@vger.kernel.org
Cc: peterz@infradead.org
Cc: brgerst@gmail.com
Cc: rostedt@goodmis.org
Cc: bp@alien8.de
Cc: luto@kernel.org
Cc: jpoimboe@redhat.com
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: torvalds@linux-foundation.org
Cc: tip-bot for Jacob Shin <tipbot@zytor.com>
Link: http://lkml.kernel.org/r/20170901082630.xvyi5bwk6etmppqc@gmail.com

* Return directly after a call of the function "kzalloc" failed
  at the beginning.

* Delete a repeated check for the local variable "bank"
  which became unnecessary with this refactoring.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Replace the specification of a data structure by a pointer dereference
as the parameter for the operator "sizeof" to make the corresponding size
determination a bit safer according to the Linux coding style convention.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Omit an extra message for a memory allocation failure in this function.

This issue was detected by using the Coccinelle software.

Link: http://events.linuxfoundation.org/sites/events/files/slides/LCJ16-Refactor_Strings-WSang_0.pdf


Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>