x86/fpu: Fix i486 + no387 boot crash by only saving FPU registers on context switch if there is an FPU

Booting an i486 with "no387 nofxsr" ends with with the following crash:

   math_emulate: 0060:c101987d
   Kernel panic - not syncing: Math emulation needed in kernel

on the first context switch in user land.

The reason is that copy_fpregs_to_fpstate() tries FNSAVE which does not work
as the FPU is turned off.

This bug was introduced in:

  f1c8cd01 ("x86/fpu: Change fpu->fpregs_active users to fpu->fpstate_active")

Add a check for X86_FEATURE_FPU before trying to save FPU registers (we
have such a check in switch_fpu_finish() already).
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Fixes: f1c8cd01 ("x86/fpu: Change fpu->fpregs_active users to fpu->fpstate_active")
Link: http://lkml.kernel.org/r/20181016202525.29437-4-bigeasy@linutronix.deSigned-off-by: Ingo Molnar <mingo@kernel.org>

Commit:

  c5bedc68 ("x86/fpu: Get rid of PF_USED_MATH usage, convert it to fpu->fpstate_active")

introduced the 'fpu' variable at top of __restore_xstate_sig(),
which now shadows the other definition:

  arch/x86/kernel/fpu/signal.c:318:28: warning: symbol 'fpu' shadows an earlier one
  arch/x86/kernel/fpu/signal.c:271:20: originally declared here

Remove the shadowed definition of 'fpu', as the two definitions are the same.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: c5bedc68 ("x86/fpu: Get rid of PF_USED_MATH usage, convert it to fpu->fpstate_active")
Link: http://lkml.kernel.org/r/20181016202525.29437-3-bigeasy@linutronix.deSigned-off-by: Ingo Molnar <mingo@kernel.org>

Commit:

  16561f27 ("x86/entry: Add some paranoid entry/exit CR3 handling comments")

... added some comments.  This improves them a bit:

 - When I first read the new comments, it was unclear to me whether
   they were referring to the case where paranoid_entry interrupted
   other entry code or where paranoid_entry was itself interrupted.
   Clarify it.

 - Remove the EBX comment.  We no longer use EBX as a SWAPGS
   indicator.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/c47daa1888dc2298e7e1d3f82bd76b776ea33393.1539542111.git.luto@kernel.orgSigned-off-by: Ingo Molnar <mingo@kernel.org>

Even if not on an entry stack, the CS's high bits must be
initialized because they are unconditionally evaluated in
PARANOID_EXIT_TO_KERNEL_MODE.

Failing to do so broke the boot on Galileo Gen2 and IOT2000 boards.

 [ bp: Make the commit message tone passive and impartial. ]

Fixes: b92a165d ("x86/entry/32: Handle Entry from Kernel-Mode on Entry-Stack")
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Joerg Roedel <jroedel@suse.de>
Acked-by: Joerg Roedel <jroedel@suse.de>
CC: "H. Peter Anvin" <hpa@zytor.com>
CC: Andrea Arcangeli <aarcange@redhat.com>
CC: Andy Lutomirski <luto@kernel.org>
CC: Boris Ostrovsky <boris.ostrovsky@oracle.com>
CC: Brian Gerst <brgerst@gmail.com>
CC: Dave Hansen <dave.hansen@intel.com>
CC: David Laight <David.Laight@aculab.com>
CC: Denys Vlasenko <dvlasenk@redhat.com>
CC: Eduardo Valentin <eduval@amazon.com>
CC: Greg KH <gregkh@linuxfoundation.org>
CC: Ingo Molnar <mingo@kernel.org>
CC: Jiri Kosina <jkosina@suse.cz>
CC: Josh Poimboeuf <jpoimboe@redhat.com>
CC: Juergen Gross <jgross@suse.com>
CC: Linus Torvalds <torvalds@linux-foundation.org>
CC: Peter Zijlstra <peterz@infradead.org>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Will Deacon <will.deacon@arm.com>
CC: aliguori@amazon.com
CC: daniel.gruss@iaik.tugraz.at
CC: hughd@google.com
CC: keescook@google.com
CC: linux-mm <linux-mm@kvack.org>
CC: x86-ml <x86@kernel.org>
Link: http://lkml.kernel.org/r/f271c747-1714-5a5b-a71f-ae189a093b8d@siemens.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

When compiling the kernel with Clang, this warning appears even though
it is disabled for the whole kernel because this folder has its own set
of KBUILD_CFLAGS. It was disabled before the beginning of git history.

In file included from arch/x86/boot/compressed/kaslr.c:29:
In file included from arch/x86/boot/compressed/misc.h:21:
In file included from ./include/linux/elf.h:5:
In file included from ./arch/x86/include/asm/elf.h:77:
In file included from ./arch/x86/include/asm/vdso.h:11:
In file included from ./include/linux/mm_types.h:9:
In file included from ./include/linux/spinlock.h:88:
In file included from ./arch/x86/include/asm/spinlock.h:43:
In file included from ./arch/x86/include/asm/qrwlock.h:6:
./include/asm-generic/qrwlock.h:101:53: warning: passing 'u32 *' (aka
'unsigned int *') to parameter of type 'int *' converts between pointers
to integer types with different sign [-Wpointer-sign]
        if (likely(atomic_try_cmpxchg_acquire(&lock->cnts, &cnts, _QW_LOCKED)))
                                                           ^~~~~
./include/linux/compiler.h:76:40: note: expanded from macro 'likely'
# define likely(x)      __builtin_expect(!!(x), 1)
                                            ^
./include/asm-generic/atomic-instrumented.h:69:66: note: passing
argument to parameter 'old' here
static __always_inline bool atomic_try_cmpxchg(atomic_t *v, int *old, int new)
                                                                 ^
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Link: https://lkml.kernel.org/r/20181013010713.6999-1-natechancellor@gmail.com

Clang warns that the declaration of jiffies in include/linux/jiffies.h
doesn't match the definition in arch/x86/time/kernel.c:

arch/x86/kernel/time.c:29:42: warning: section does not match previous declaration [-Wsection]
__visible volatile unsigned long jiffies __cacheline_aligned = INITIAL_JIFFIES;
                                         ^
./include/linux/cache.h:49:4: note: expanded from macro '__cacheline_aligned'
                 __section__(".data..cacheline_aligned")))
                 ^
./include/linux/jiffies.h:81:31: note: previous attribute is here
extern unsigned long volatile __cacheline_aligned_in_smp __jiffy_arch_data jiffies;
                              ^
./arch/x86/include/asm/cache.h:20:2: note: expanded from macro '__cacheline_aligned_in_smp'
        __page_aligned_data
        ^
./include/linux/linkage.h:39:29: note: expanded from macro '__page_aligned_data'
#define __page_aligned_data     __section(.data..page_aligned) __aligned(PAGE_SIZE)
                                ^
./include/linux/compiler_attributes.h:233:56: note: expanded from macro '__section'
#define __section(S)                    __attribute__((__section__(#S)))
                                                       ^
1 warning generated.

The declaration was changed in commit 7c30f352 ("jiffies.h: declare
jiffies and jiffies_64 with ____cacheline_aligned_in_smp") but wasn't
updated here. Make them match so Clang no longer warns.

Fixes: 7c30f352 ("jiffies.h: declare jiffies and jiffies_64 with ____cacheline_aligned_in_smp")
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20181013005311.28617-1-natechancellor@gmail.com

Andi Kleen was just asking me about the NMI CR3 handling and why
we restore it unconditionally.  I was *sure* we had documented it
well.  We did not.

Add some documentation.  We have common entry code where the CR3
value is stashed, but three places in two big code paths where we
restore it.  I put bulk of the comments in this common path and
then refer to it from the other spots.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: luto@kernel.org
Cc: bp@alien8.de
Cc: "H. Peter Anvin" <hpa@zytor.come
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Link: https://lkml.kernel.org/r/20181012232118.3EAAE77B@viggo.jf.intel.com

Eric reported that a sequence count loop using this_cpu_read() got
optimized out. This is wrong, this_cpu_read() must imply READ_ONCE()
because the interface is IRQ-safe, therefore an interrupt can have
changed the per-cpu value.

Fixes: 7c3576d2 ("[PATCH] i386: Convert PDA into the percpu section")
Reported-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Eric Dumazet <edumazet@google.com>
Cc: hpa@zytor.com
Cc: eric.dumazet@gmail.com
Cc: bp@alien8.de
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20181011104019.748208519@infradead.org

Looking at the asm for native_sched_clock() I noticed we don't inline
enough. Mostly caused by sharing code with cyc2ns_read_begin(), which
we didn't used to do. So mark all that __force_inline to make it DTRT.

Fixes: 59eaef78 ("x86/tsc: Remodel cyc2ns to use seqcount_latch()")
Reported-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: hpa@zytor.com
Cc: eric.dumazet@gmail.com
Cc: bp@alien8.de
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20181011104019.695196158@infradead.org

Dan writes:
  "libnvdimm/dax 4.19-rc8

   * Fix a livelock in dax_layout_busy_page() present since v4.18. The
     lockup triggers when truncating an actively mapped huge page out of
     a mapping pinned for direct-I/O.

   * Fix mprotect() clobbers of _PAGE_DEVMAP. Broken since v4.5
     mprotect() clears this flag that is needed to communicate the
     liveness of device pages to the get_user_pages() path."

* tag 'libnvdimm-fixes-4.19-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  mm: Preserve _PAGE_DEVMAP across mprotect() calls
  filesystem-dax: Fix dax_layout_busy_page() livelock

Wolfram writes:
  "i2c fix for 4.19:

   I2C has one documentation bugfix for something we changed during the
   v4.19 cycle"

* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: Fix kerneldoc for renamed i2c dma put function

Paolo writes:
  "KVM fixes for 4.19-rc8

   Leftover bugfixes."

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: vmx: hyper-v: don't pass EPT configuration info to vmx_hv_remote_flush_tlb()
  KVM: x86: support CONFIG_KVM_AMD=y with CONFIG_CRYPTO_DEV_CCP_DD=m
  ARM: KVM: Correctly order SGI register entries in the cp15 array

I'm observing random crashes in multi-vCPU L2 guests running on KVM on
Hyper-V. I bisected the issue to the commit 877ad952 ("KVM: vmx: Add
tlb_remote_flush callback support"). Hyper-V TLFS states:

"AddressSpace specifies an address space ID (an EPT PML4 table pointer)"

So apparently, Hyper-V doesn't expect us to pass naked EPTP, only PML4
pointer should be used. Strip off EPT configuration information before
calling into vmx_hv_remote_flush_tlb().

Fixes: 877ad952 ("KVM: vmx: Add tlb_remote_flush callback support")
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

ubifs_assert() is not WARN_ON(), so we have to invert
the checks.
Randy faced this warning with UBIFS being a module, since
most users use UBIFS as builtin because UBIFS is the rootfs
nobody noticed so far. :-(
Including me.
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Fixes: 54169ddd ("ubifs: Turn two ubifs_assert() into a WARN_ON()")
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Fixes from Andrew:

* akpm:
  fs/fat/fatent.c: add cond_resched() to fat_count_free_clusters()
  mm/thp: fix call to mmu_notifier in set_pmd_migration_entry() v2
  mm/mmap.c: don't clobber partially overlapping VMA with MAP_FIXED_NOREPLACE
  ocfs2: fix a GCC warning

On non-preempt kernels this loop can take a long time (more than 50 ticks)
processing through entries.

Link: http://lkml.kernel.org/r/20181010172623.57033-1-khazhy@google.comSigned-off-by: Khazhismel Kumykov <khazhy@google.com>
Acked-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Inside set_pmd_migration_entry() we are holding page table locks and thus
we can not sleep so we can not call invalidate_range_start/end()

So remove call to mmu_notifier_invalidate_range_start/end() because they
are call inside the function calling set_pmd_migration_entry() (see
try_to_unmap_one()).

Link: http://lkml.kernel.org/r/20181012181056.7864-1-jglisse@redhat.comSigned-off-by: Jérôme Glisse <jglisse@redhat.com>
Reported-by: Andrea Arcangeli <aarcange@redhat.com>
Reviewed-by: Zi Yan <zi.yan@cs.rutgers.edu>
Acked-by: Michal Hocko <mhocko@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: David Nellans <dnellans@nvidia.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Daniel Micay reports that attempting to use MAP_FIXED_NOREPLACE in an
application causes that application to randomly crash.  The existing check
for handling MAP_FIXED_NOREPLACE looks up the first VMA that either
overlaps or follows the requested region, and then bails out if that VMA
overlaps *the start* of the requested region.  It does not bail out if the
VMA only overlaps another part of the requested region.

Fix it by checking that the found VMA only starts at or after the end of
the requested region, in which case there is no overlap.

Test case:

user@debian:~$ cat mmap_fixed_simple.c
#include <sys/mman.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

#ifndef MAP_FIXED_NOREPLACE
#define MAP_FIXED_NOREPLACE 0x100000
#endif

int main(void) {
  char *p;

  errno = 0;
  p = mmap((void*)0x10001000, 0x4000, PROT_NONE,
MAP_PRIVATE|MAP_ANONYMOUS|MAP_FIXED_NOREPLACE, -1, 0);
  printf("p1=%p err=%m\n", p);

  errno = 0;
  p = mmap((void*)0x10000000, 0x2000, PROT_READ,
MAP_PRIVATE|MAP_ANONYMOUS|MAP_FIXED_NOREPLACE, -1, 0);
  printf("p2=%p err=%m\n", p);

  char cmd[100];
  sprintf(cmd, "cat /proc/%d/maps", getpid());
  system(cmd);

  return 0;
}
user@debian:~$ gcc -o mmap_fixed_simple mmap_fixed_simple.c
user@debian:~$ ./mmap_fixed_simple
p1=0x10001000 err=Success
p2=0x10000000 err=Success
10000000-10002000 r--p 00000000 00:00 0
10002000-10005000 ---p 00000000 00:00 0
564a9a06f000-564a9a070000 r-xp 00000000 fe:01 264004
  /home/user/mmap_fixed_simple
564a9a26f000-564a9a270000 r--p 00000000 fe:01 264004
  /home/user/mmap_fixed_simple
564a9a270000-564a9a271000 rw-p 00001000 fe:01 264004
  /home/user/mmap_fixed_simple
564a9a54a000-564a9a56b000 rw-p 00000000 00:00 0                          [heap]
7f8eba447000-7f8eba5dc000 r-xp 00000000 fe:01 405885
  /lib/x86_64-linux-gnu/libc-2.24.so
7f8eba5dc000-7f8eba7dc000 ---p 00195000 fe:01 405885
  /lib/x86_64-linux-gnu/libc-2.24.so
7f8eba7dc000-7f8eba7e0000 r--p 00195000 fe:01 405885
  /lib/x86_64-linux-gnu/libc-2.24.so
7f8eba7e0000-7f8eba7e2000 rw-p 00199000 fe:01 405885
  /lib/x86_64-linux-gnu/libc-2.24.so
7f8eba7e2000-7f8eba7e6000 rw-p 00000000 00:00 0
7f8eba7e6000-7f8eba809000 r-xp 00000000 fe:01 405876
  /lib/x86_64-linux-gnu/ld-2.24.so
7f8eba9e9000-7f8eba9eb000 rw-p 00000000 00:00 0
7f8ebaa06000-7f8ebaa09000 rw-p 00000000 00:00 0
7f8ebaa09000-7f8ebaa0a000 r--p 00023000 fe:01 405876
  /lib/x86_64-linux-gnu/ld-2.24.so
7f8ebaa0a000-7f8ebaa0b000 rw-p 00024000 fe:01 405876
  /lib/x86_64-linux-gnu/ld-2.24.so
7f8ebaa0b000-7f8ebaa0c000 rw-p 00000000 00:00 0
7ffcc99fa000-7ffcc9a1b000 rw-p 00000000 00:00 0                          [stack]
7ffcc9b44000-7ffcc9b47000 r--p 00000000 00:00 0                          [vvar]
7ffcc9b47000-7ffcc9b49000 r-xp 00000000 00:00 0                          [vdso]
ffffffffff600000-ffffffffff601000 r-xp 00000000 00:00 0
  [vsyscall]
user@debian:~$ uname -a
Linux debian 4.19.0-rc6+ #181 SMP Wed Oct 3 23:43:42 CEST 2018 x86_64 GNU/Linux
user@debian:~$

As you can see, the first page of the mapping at 0x10001000 was clobbered.

Link: http://lkml.kernel.org/r/20181010152736.99475-1-jannh@google.com
Fixes: a4ff8e86 ("mm: introduce MAP_FIXED_NOREPLACE")
Signed-off-by: Jann Horn <jannh@google.com>
Reported-by: Daniel Micay <danielmicay@gmail.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: John Hubbard <jhubbard@nvidia.com>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Fix the following compile warning:

fs/ocfs2/dlmglue.c:99:30: warning: ‘lockdep_keys’ defined but not used [-Wunused-variable]
 static struct lock_class_key lockdep_keys[OCFS2_NUM_LOCK_TYPES];

Link: http://lkml.kernel.org/r/1536938148-32110-1-git-send-email-zhongjiang@huawei.comSigned-off-by: zhong jiang <zhongjiang@huawei.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Jens writes:
  "block fix for 4.19-rc

   Just a single fix that should go in, fixing a regression introduced
   in the blk-wbt code."

* tag 'for-linus-20181012' of git://git.kernel.dk/linux-block:
  blk-wbt: wake up all when we scale up, not down

Andreas writes:
  "gfs2 4.19 fixes

   Fix iomap buffered write support for journaled files"

* tag 'gfs2-4.19.fixes3' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
  gfs2: Fix iomap buffered write support for journaled files (2)

Will writes:
  "More arm64 fixes

   - Reject CHAIN PMU events when they are not part of a 64-bit counter

   - Fix WARN_ON_ONCE() that triggers for reserved regions that don't
     correspond to mapped memory"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: perf: Reject stand-alone CHAIN events for PMUv3
  arm64: Fix /proc/iomem for reserved but not memory regions

Arnd writes:
  "ARM: SoC fixes for 4.19

   Two last minute bugfixes, both for NXP platforms:

   * The Layerscape 'qbman' infrastructure suffers from probe ordering
     bugs in some configurations, a two-patch series adds a hotfix for
     this. 4.20 will have a longer set of patches to rework it.

   * The old imx53-qsb board regressed in 4.19 after the addition
     of cpufreq support, adding a set of explicit operating points
     fixes this."

* tag 'armsoc-fixes-4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
  soc: fsl: qman_portals: defer probe after qman's probe
  soc: fsl: qbman: add APIs to retrieve the probing status
  ARM: dts: imx53-qsb: disable 1.2GHz OPP

Fix a leak of afs_server structs.  The routine that installs them in the
various lookup lists and trees gets a ref on leaving the function, whether
it added the server or a server already exists.  It shouldn't increment
the refcount if it added the server.

The effect of this that "rmmod kafs" will hang waiting for the leaked
server to become unused.

Fixes: d2ddc776 ("afs: Overhaul volume and server record caching and fileserver rotation")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Just drop the "linux" part of the path, it was never correct.
Reported-by: Joe Perches <joe@perches.com>
Fixes: 256ac037 ("dt-bindings: document devicetree bindings for mux-controllers and gpio-mux")
Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The file is GPL v2 or later.
Acked-by: Mircea Caprioru <mircea.caprioru@analog.com>
Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

It turns out that the fix in commit 6636c3cc56 is bad; the assertion
that the iomap code no longer creates buffer heads is incorrect for
filesystems that set the IOMAP_F_BUFFER_HEAD flag.

Instead, what's happening is that gfs2_iomap_begin_write treats all
files that have the jdata flag set as journaled files, which is
incorrect as long as those files are inline ("stuffed").  We're handling
stuffed files directly via the page cache, which is why we ended up with
pages without buffer heads in gfs2_page_add_databufs.

Fix this by handling stuffed journaled files correctly in
gfs2_iomap_begin_write.

This reverts commit 6636c3cc5690c11631e6366cf9a28fb99c8b25bb.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

It doesn't make sense for a perf event to be configured as a CHAIN event
in isolation, so extend the arm_pmu structure with a ->filter_match()
function to allow the backend PMU implementation to reject CHAIN events
early.

Cc: <stable@vger.kernel.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

We describe ranges of 'reserved' memory to userspace via /proc/iomem.
Commit 50d7ba36 ("arm64: export memblock_reserve()d regions via
/proc/iomem") updated the logic to export regions that were reserved
because their contents should be preserved. This allowed kexec-tools
to tell the difference between 'reserved' memory that must be
preserved and not overwritten, (e.g. the ACPI tables), and 'nomap'
memory that must not be touched without knowing the memory-attributes
(e.g. RAS CPER regions).

The above commit wrongly assumed that memblock_reserve() would not
be used to reserve regions that aren't memory. It turns out this is
exactly what early_init_dt_reserve_memory_arch() will do if it finds
a DT reserved-memory that was also carved out of the memory node, which
results in a WARN_ON_ONCE() and the region being reserved instead of
ignored. The ramoops description on hikey and dragonboard-410c both do
this, so we can't simply write this configuration off as "buggy firmware".

Avoid this issue by rewriting reserve_memblock_reserved_regions() so
that only the portions of reserved regions which overlap with mapped
memory are actually reserved.

Fixes: 50d7ba36 ("arm64: export memblock_reserve()d regions via /proc/iomem")
Reported-by: John Stultz <john.stultz@linaro.org>
Reported-by: Paolo Pisati <p.pisati@gmail.com>
CC: Akashi Takahiro <takahiro.akashi@linaro.org>
CC: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: James Morse <james.morse@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

Access to the list of cells by /proc/net/afs/cells has a couple of
problems:

 (1) It should be checking against SEQ_START_TOKEN for the keying the
     header line.

 (2) It's only holding the RCU read lock, so it can't just walk over the
     list without following the proper RCU methods.

Fix these by using an hlist instead of an ordinary list and using the
appropriate accessor functions to follow it with RCU.

Since the code that adds a cell to the list must also necessarily change,
sort the list on insertion whilst we're at it.

Fixes: 989782dc ("afs: Overhaul cell database management")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Ulf writes:
   "MMC core:
    - Avoid fragile multiblock reads for the last sector in SPI mode
    WIFI/SDIO:
    - libertas: Fixup suspend sequence for the SDIO card"

* tag 'mmc-v4.19-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc:
  libertas: call into generic suspend code before turning off power
  mmc: block: avoid multiblock reads for the last sector in SPI mode

Linus writes:
  "GPIO fix for the v4.19 series:
   - Fix up the interrupt parent for the irqdomains."

* tag 'gpio-v4.19-4' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio:
  gpio: Assign gpio_irq_chip::parents to non-stack pointer

Linus writes:
  "pin control fix for v4.19:

   A single pin control fix for v4.19:
   - Interrupt setup in the MCP23S08 driver."

* tag 'pinctrl-v4.19-5' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl:
  pinctrl: mcp23s08: fix irq and irqchip setup order

Boris writes:
  "mdt: fix for 4.19-rc8

   * Fix a stack overflow in lib/bch.c"

* tag 'mtd/fixes-for-4.19-rc8' of git://git.infradead.org/linux-mtd:
  lib/bch: fix possible stack overrun

Dave writes:
  "drm fixes for 4.19-rc8

   single nouveau runtime reference and mst change"

* tag 'drm-fixes-2018-10-12-1' of git://anongit.freedesktop.org/drm/drm:
  drm/nouveau/drm/nouveau: Grab runtime PM ref in nv50_mstc_detect()

Doug writes:
  "RDMA fixes:

   Final for-rc pull request for 4.19

   We only have one bug to submit this time around.  It fixes a DMA
   unmap issue where we unmapped the DMA address from the IOMMU before
   we did from the card, resulting in a DMAR error with IOMMU enabled,
   or possible crash without."

* tag 'for-gkh' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma:
  IB/mlx5: Unmap DMA addr from HCA before IOMMU

Dmitry writes:
  "Input updates for v4.19-rc7

   - we added a few scheduling points into various input interfaces to
     ensure that large writes will not cause RCU stalls
   - fixed configuring PS/2 keyboards as wakeup devices on newer
     platforms
   - added a new Xbox gamepad ID."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
  Input: uinput - add a schedule point in uinput_inject_events()
  Input: evdev - add a schedule point in evdev_write()
  Input: mousedev - add a schedule point in mousedev_write()
  Input: i8042 - enable keyboard wakeups by default when s2idle is used
  Input: xpad - add support for Xbox1 PDP Camo series gamepad

Stephen writes:
  "A couple of warning fixes:

  Two fixes from Peter Oberparleiter <oberpar@linux.ibm.com>:
    Commit 6b7dca40 ("tracing: Allow gcov profiling on only ftrace subsystem")
   uncovered linker problems when using gcov kernel profiling on some
   architectures. These problems were likely introduced earlier, and are
   possibly related to compiler changes."

* tag 'next-fixes-20181012' of git://git.kernel.org/pub/scm/linux/kernel/git/sfr/next-fixes:
  vmlinux.lds.h: Fix linker warnings about orphan .LPBX sections
  vmlinux.lds.h: Fix incomplete .text.exit discards

The previous patch introduced very large kernel stack usage and a Makefile
change to hide the warning about it.

From what I can tell, a number of things went wrong here:

- The BCH_MAX_T constant was set to the maximum value for 'n',
  not the maximum for 't', which is much smaller.

- The stack usage is actually larger than the entire kernel stack
  on some architectures that can use 4KB stacks (m68k, sh, c6x), which
  leads to an immediate overrun.

- The justification in the patch description claimed that nothing
  changed, however that is not the case even without the two points above:
  the configuration is machine specific, and most boards  never use the
  maximum BCH_ECC_WORDS() length but instead have something much smaller.
  That maximum would only apply to machines that use both the maximum
  block size and the maximum ECC strength.

The largest value for 't' that I could find is '32', which in turn leads
to a 60 byte array instead of 2048 bytes. Making it '64' for future
extension seems also worthwhile, with 120 bytes for the array. Anything
larger won't fit into the OOB area on NAND flash.

With that changed, the warning can be enabled again.

Only linux-4.19+ contains the breakage, so this is only needed
as a stable backport if it does not make it into the release.

Fixes: 02361bc7 ("lib/bch: Remove VLA usage")
Reported-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: stable@vger.kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>

David writes:
  "Networking

   1) RXRPC receive path fixes from David Howells.

   2) Re-export __skb_recv_udp(), from Jiri Kosina.

   3) Fix refcounting in u32 classificer, from Al Viro.

   4) Userspace netlink ABI fixes from Eugene Syromiatnikov.

   5) Don't double iounmap on rmmod in ena driver, from Arthur
      Kiyanovski.

   6) Fix devlink string attribute handling, we must pull a copy into a
      kernel buffer if the lifetime extends past the netlink request.
      From Moshe Shemesh.

   7) Fix hangs in RDS, from Ka-Cheong Poon.

   8) Fix recursive locking lockdep warnings in tipc, from Ying Xue.

   9) Clear RX irq correctly in socionext, from Ilias Apalodimas.

   10) bcm_sf2 fixes from Florian Fainelli."

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (38 commits)
  net: dsa: bcm_sf2: Call setup during switch resume
  net: dsa: bcm_sf2: Fix unbind ordering
  net: phy: sfp: remove sfp_mutex's definition
  r8169: set RX_MULTI_EN bit in RxConfig for 8168F-family chips
  net: socionext: clear rx irq correctly
  net/mlx4_core: Fix warnings during boot on driverinit param set failures
  tipc: eliminate possible recursive locking detected by LOCKDEP
  selftests: udpgso_bench.sh explicitly requires bash
  selftests: rtnetlink.sh explicitly requires bash.
  qmi_wwan: Added support for Gemalto's Cinterion ALASxx WWAN interface
  tipc: queue socket protocol error messages into socket receive buffer
  tipc: set link tolerance correctly in broadcast link
  net: ipv4: don't let PMTU updates increase route MTU
  net: ipv4: update fnhe_pmtu when first hop's MTU changes
  net/ipv6: stop leaking percpu memory in fib6 info
  rds: RDS (tcp) hangs on sendto() to unresponding address
  net: make skb_partial_csum_set() more robust against overflows
  devlink: Add helper function for safely copy string param
  devlink: Fix param cmode driverinit for string type
  devlink: Fix param set handling for string type
  ...