Currently, efi_mem_reserve_persistent() may not be called from atomic
context, since both the kmalloc() call and the memremap() call may
sleep.

The kmalloc() call is easy enough to fix, but the memremap() call
needs to be moved into an init hook since we cannot control the
memory allocation behavior of memremap() at the call site.
Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20181114175544.12860-6-ard.biesheuvel@linaro.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>

The new memory EFI reservation feature we introduced to allow memory
reservations to persist across kexec may trigger an unbounded number
of calls to memblock_reserve(). The memblock subsystem can deal with
this fine, but not before memblock resizing is enabled, which we can
only do after paging_init(), when the memory we reallocate the array
into is actually mapped.

So break out the memreserve table processing into a separate routine
and call it after paging_init() on arm64. On ARM, because of limited
reviewing bandwidth of the maintainer, we cannot currently fix this,
so instead, disable the EFI persistent memreserve entirely on ARM so
we can fix it later.
Tested-by: NMarc Zyngier <marc.zyngier@arm.com>
Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20181114175544.12860-5-ard.biesheuvel@linaro.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>

Commit:

  24d7c494 ("efi/arm-stub: Round up FDT allocation to mapping size")

increased the allocation size for the FDT image created by the stub to a
fixed value of 2 MB, to simplify the former code that made several
attempts with increasing values for the size. This is reasonable
given that the allocation is of type EFI_LOADER_DATA, which is released
to the kernel unless it is explicitly memblock_reserve()d by the early
boot code.

However, this allocation size leaked into the 'size' field of the FDT
header metadata, and so the entire allocation remains occupied by the
device tree binary, even if most of it is not used to store device tree
information.

So call fdt_pack() to shrink the FDT data structure to its minimum size
after populating all the fields, so that the remaining memory is no
longer wasted.
Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
Cc: <stable@vger.kernel.org> # v4.12+
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Fixes: 24d7c494 ("efi/arm-stub: Round up FDT allocation to mapping size")
Link: http://lkml.kernel.org/r/20181114175544.12860-4-ard.biesheuvel@linaro.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>

Commit:

  3ea86495 ("efi/arm: preserve early mapping of UEFI memory map longer for BGRT")

deferred the unmap of the early mapping of the UEFI memory map to
accommodate the ACPI BGRT code, which looks up the memory type that
backs the BGRT table to validate it against the requirements of the UEFI spec.

Unfortunately, this causes problems on ARM, which does not permit
early mappings to persist after paging_init() is called, resulting
in a WARN() splat. Since we don't support the BGRT table on ARM anway,
let's revert ARM to the old behaviour, which is to take down the
early mapping at the end of efi_init().
Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Fixes: 3ea86495 ("efi/arm: preserve early mapping of UEFI memory ...")
Link: http://lkml.kernel.org/r/20181114175544.12860-3-ard.biesheuvel@linaro.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>

The following commit:

  9dbbedaa ("efi: Make efi_rts_work accessible to efi page fault handler")

converted 'efi_rts_work' from an auto variable to a global variable.
However, when submitting the work, INIT_WORK_ONSTACK() was still used,
causing the following complaint from debugobjects:

  ODEBUG: object 00000000ed27b500 is NOT on stack 00000000c7d38760, but annotated.

Change the macro to just INIT_WORK() to eliminate the warning.
Signed-off-by: NWaiman Long <longman@redhat.com>
Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: NSai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Fixes: 9dbbedaa ("efi: Make efi_rts_work accessible to efi page fault handler")
Link: http://lkml.kernel.org/r/20181114175544.12860-2-ard.biesheuvel@linaro.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>

Merge tag 'riscv-for-linus-4.20-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux

Pull RISC-V fixes from Palmer Dabbelt:
 "This contains a few patches that fix various issues in the RISC-V
  port:

   - enable printk timestamps in the RISC-V defconfig.

   - a whitespace fix to "struct pt_regs".

   - add a "vdso_install" target for RISC-V.

   - a pair of build fixes: one to fix a typo in our makefile, and one
     to clean up some warnings.

  There will probably be more patches from us for 4.20, but I don't have
  anything that's ready to go right now so I'm going to hold off a bit.

  Right now the only concrete thing I know I want to make sure gets
  sorted out is our 32-bit stat interface, which I don't want sitting in
  limbo for another cycle as we have to get RV32I glibc sone"

* tag 'riscv-for-linus-4.20-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux:
  RISC-V: Silence some module warnings on 32-bit
  RISC-V: lib: Fix build error for 64-bit
  riscv: add missing vdso_install target
  riscv: fix spacing in struct pt_regs
  RISC-V: defconfig: Enable printk timestamps

Pull kgdb fixes from Daniel Thompson:
 "The most important changes here are two fixes for kdb regressions
  causes by the hashing of %p pointers together with a fix for a
  potential overflow in kdb tab completion handling (and warning fix).

  Also included are a set of changes in preparation to (eventually)
  enable -Wimplicit-fallthrough"

* tag 'kgdb-fixes-4.20-rc3' of https://git.linaro.org/people/daniel.thompson/linux:
  kdb: kdb_support: mark expected switch fall-throughs
  kdb: kdb_keyboard: mark expected switch fall-throughs
  kdb: kdb_main: refactor code in kdb_md_line
  kdb: Use strscpy with destination buffer size
  kdb: print real address of pointers instead of hashed addresses
  kdb: use correct pointer when 'btc' calls 'btt'

Merge branch 'fixes-v4.20-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security

Pull integrity fix from James Morris:
 "Fix a bug introduced with in this merge window in 82f94f24 ("KEYS:
  Provide software public key query function [ver #2]")"

* 'fixes-v4.20-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
  integrity: support new struct public_key_signature encoding field

Pull ACPI fix from Rafael Wysocki:
 "Fix a recently introduced build issue in the xpower PMIC driver (Arnd
  Bergmann)"

* tag 'acpi-4.20-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI / PMIC: xpower: fix IOSF_MBI dependency

Pull power management fixes from Rafael Wysocki:
 "These remove a stale DT entry left behind after recent removal of a
  cpufreq driver without users, fix up error handling in the imx6q
  cpufreq driver, fix two issues in the cpufreq documentation, and
  update the ARM cpufreq driver.

  Specifics:

   - Drop stale DT binding for the arm_big_little_dt driver removed
     recently (Sudeep Holla).

   - Fix up error handling in the imx6q cpufreq driver to make it report
     voltage scaling failures (Anson Huang).

   - Fix two issues in the cpufreq documentation (Viresh Kumar, Zhao Wei
     Liew).

   - Fix ARM cpuidle driver initialization regression from the 4.19 time
     frame and rework the driver registration part of it to simplify
     code (Ulf Hansson)"

* tag 'pm-4.20-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ARM: cpuidle: Convert to use cpuidle_register|unregister()
  ARM: cpuidle: Don't register the driver when back-end init returns -ENXIO
  dt-bindings: cpufreq: remove stale arm_big_little_dt entry
  Documentation: cpufreq: Correct a typo
  cpufreq: imx6q: add return value check for voltage scale
  Documentation: cpu-freq: Frequencies aren't always sorted

Pull nfsd fixes from Bruce Fields:
 "Three nfsd bugfixes.

  None are new bugs, but they all take a little effort to hit, which
  might explain why they weren't found sooner"

* tag 'nfsd-4.20-1' of git://linux-nfs.org/~bfields/linux:
  SUNRPC: drop pointless static qualifier in xdr_get_next_encode_buffer()
  nfsd: COPY and CLONE operations require the saved filehandle to be set
  sunrpc: correct the computation for page_ptr when truncating

Pull PCI fix from Bjorn Helgaas:
 "Revert a _PXM change that causes silent early boot failure on some AMD
  ThreadRipper systems"

* tag 'pci-v4.20-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
  Revert "ACPI/PCI: Pay attention to device-specific _PXM node values"

Pull SCSI fixes from James Bottomley:
 "This is mostly a set of minor and obvious fixes (three in one of the
  new drivers).

  The only substantial change is to move the ufs to the blk-mq now that
  the merge window fixed the suspend/resume issues with blk-mq"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: qla2xxx: Initialize port speed to avoid setting lower speed
  Revert "scsi: ufs: Disable blk-mq for now"
  scsi: NCR5380: Return false instead of NULL
  scsi: qla2xxx: Fix a typo in MODULE_PARM_DESC
  scsi: hisi_sas: Remove set but not used variable 'dq_list'
  scsi: myrs: only build on little-endian platforms
  scsi: myrs: avoid stack overflow warning
  scsi: lpfc: fix remoteport access
  scsi: myrb: fix sprintf buffer overflow warning
  scsi: target/core: Avoid that a kernel oops is triggered when COMPARE AND WRITE fails

Pull RTC driver fixes from Alexandre Belloni:

 - cmos: stop exporting alarms when not supported

 - hctosys: correctly report range error

 - pcf2127: fix a memory leak

* tag 'rtc-4.20-2' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux:
  rtc: pcf2127: fix a kmemleak caused in pcf2127_i2c_gather_write
  rtc: hctosys: Add missing range error reporting
  rtc: cmos: Do not export alarm rtc_ops when we do not support alarms

Pull namespace fix from Eric Biederman:
 "Benjamin Coddington noticed an unkillable busy loop in the kernel that
  anyone who is sufficiently motivated can trigger. This bug did not
  exist in earlier kernels making this bug a regression.

  I have tested the change personally and confirmed that the bug exists
  and that the fix works. This fix has been picked up by linux-next and
  hopefully the automated testing bots and no problems have been
  reported from those sources.

  Ordinarily I would let something like this sit a little longer but I
  am going to be away at Linux Plumbers the rest of this week and I am
  afraid if I don't send the pull request now this fix will get lost"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  mnt: fix __detach_mounts infinite loop

Pull parisc fix from Helge Deller:
 "Revert one patch which changed how spinlocks get released. It breaks
  the rwlock implementation in glibc"

* 'parisc-4.20-3' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  parisc: Revert "Release spinlocks using ordered store"

Pull ARM fix from Russell King:
 "It was noticed that one of Julien's patches contained an error, this
  fixes that up"

* 'spectre' of git://git.armlinux.org.uk/~rmk/linux-arm:
  ARM: 8810/1: vfp: Fix wrong assignement to ufp_exc

On systems with IMA-appraisal enabled with a policy requiring file
signatures, the "good" signature values are stored on the filesystem as
extended attributes (security.ima).  Signature verification failure
would normally be limited to just a particular file (eg. executable),
but during boot signature verification failure could result in a system
hang.

Defining and requiring a new public_key_signature field requires all
callers of asymmetric signature verification to be updated to reflect
the change.  This patch updates the integrity asymmetric_verify()
caller.

Fixes: 82f94f24 ("KEYS: Provide software public key query function [ver #2]")
Signed-off-by: NMimi Zohar <zohar@linux.ibm.com>
Cc: David Howells <dhowells@redhat.com>
Acked-by: NDenis Kenzior <denkenz@gmail.com>
Signed-off-by: NJames Morris <james.morris@microsoft.com>

In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.

Notice that in this particular case, I replaced the code comments with
a proper "fall through" annotation, which is what GCC is expecting
to find.
Signed-off-by: NGustavo A. R. Silva <gustavo@embeddedor.com>
Reviewed-by: NDaniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: NDaniel Thompson <daniel.thompson@linaro.org>

In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.

Notice that in this particular case, I replaced the code comments with
a proper "fall through" annotation, which is what GCC is expecting
to find.
Signed-off-by: NGustavo A. R. Silva <gustavo@embeddedor.com>
Reviewed-by: NDaniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: NDaniel Thompson <daniel.thompson@linaro.org>

Replace the whole switch statement with a for loop.  This makes the
code clearer and easy to read.

This also addresses the following Coverity warnings:

Addresses-Coverity-ID: 115090 ("Missing break in switch")
Addresses-Coverity-ID: 115091 ("Missing break in switch")
Addresses-Coverity-ID: 114700 ("Missing break in switch")
Suggested-by: NDaniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: NGustavo A. R. Silva <gustavo@embeddedor.com>
Reviewed-by: NDaniel Thompson <daniel.thompson@linaro.org>
[daniel.thompson@linaro.org: Tiny grammar change in description]
Signed-off-by: NDaniel Thompson <daniel.thompson@linaro.org>

gcc 8.1.0 warns with:

kernel/debug/kdb/kdb_support.c: In function ‘kallsyms_symbol_next’:
kernel/debug/kdb/kdb_support.c:239:4: warning: ‘strncpy’ specified bound depends on the length of the source argument [-Wstringop-overflow=]
     strncpy(prefix_name, name, strlen(name)+1);
     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
kernel/debug/kdb/kdb_support.c:239:31: note: length computed here

Use strscpy() with the destination buffer size, and use ellipses when
displaying truncated symbols.

v2: Use strscpy()
Signed-off-by: NPrarit Bhargava <prarit@redhat.com>
Cc: Jonathan Toppins <jtoppins@redhat.com>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Daniel Thompson <daniel.thompson@linaro.org>
Cc: kgdb-bugreport@lists.sourceforge.net
Reviewed-by: NDaniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: NDaniel Thompson <daniel.thompson@linaro.org>

Since commit ad67b74d ("printk: hash addresses printed with %p"),
all pointers printed with %p are printed with hashed addresses
instead of real addresses in order to avoid leaking addresses in
dmesg and syslog. But this applies to kdb too, with is unfortunate:

    Entering kdb (current=0x(ptrval), pid 329) due to Keyboard Entry
    kdb> ps
    15 sleeping system daemon (state M) processes suppressed,
    use 'ps A' to see all.
    Task Addr       Pid   Parent [*] cpu State Thread     Command
    0x(ptrval)      329      328  1    0   R  0x(ptrval) *sh

    0x(ptrval)        1        0  0    0   S  0x(ptrval)  init
    0x(ptrval)        3        2  0    0   D  0x(ptrval)  rcu_gp
    0x(ptrval)        4        2  0    0   D  0x(ptrval)  rcu_par_gp
    0x(ptrval)        5        2  0    0   D  0x(ptrval)  kworker/0:0
    0x(ptrval)        6        2  0    0   D  0x(ptrval)  kworker/0:0H
    0x(ptrval)        7        2  0    0   D  0x(ptrval)  kworker/u2:0
    0x(ptrval)        8        2  0    0   D  0x(ptrval)  mm_percpu_wq
    0x(ptrval)       10        2  0    0   D  0x(ptrval)  rcu_preempt

The whole purpose of kdb is to debug, and for debugging real addresses
need to be known. In addition, data displayed by kdb doesn't go into
dmesg.

This patch replaces all %p by %px in kdb in order to display real
addresses.

Fixes: ad67b74d ("printk: hash addresses printed with %p")
Cc: <stable@vger.kernel.org>
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NDaniel Thompson <daniel.thompson@linaro.org>

On a powerpc 8xx, 'btc' fails as follows:

Entering kdb (current=0x(ptrval), pid 282) due to Keyboard Entry
kdb> btc
btc: cpu status: Currently on cpu 0
Available cpus: 0
kdb_getarea: Bad address 0x0

when booting the kernel with 'debug_boot_weak_hash', it fails as well

Entering kdb (current=0xba99ad80, pid 284) due to Keyboard Entry
kdb> btc
btc: cpu status: Currently on cpu 0
Available cpus: 0
kdb_getarea: Bad address 0xba99ad80

On other platforms, Oopses have been observed too, see
https://github.com/linuxppc/linux/issues/139

This is due to btc calling 'btt' with %p pointer as an argument.

This patch replaces %p by %px to get the real pointer value as
expected by 'btt'

Fixes: ad67b74d ("printk: hash addresses printed with %p")
Cc: <stable@vger.kernel.org>
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: NDaniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: NDaniel Thompson <daniel.thompson@linaro.org>

This reverts commit bad7dcd9.

bad7dcd9 ("ACPI/PCI: Pay attention to device-specific _PXM node
values") caused boot failures (no console output at all) for Martin [1]
and Ingo [2] on AMD ThreadRipper systems.

Revert the commit until we figure out how to safely use these
device-specific _PXM values.

[1] https://lore.kernel.org/linux-pci/20180912152140.3676-2-Jonathan.Cameron@huawei.com
[2] https://lore.kernel.org/linux-pci/20181113071712.GA2353@gmail.com
Fixes: bad7dcd9 ("ACPI/PCI: Pay attention to device-specific _PXM node values")
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

Fixes:

arch/riscv/kernel/module.c: In function 'apply_r_riscv_32_rela':
./include/linux/kern_levels.h:5:18: warning: format '%llx' expects argument of type 'long long unsigned int', but argument 3 has type 'Elf32_Addr' {aka 'unsigned int'} [-Wformat=]
arch/riscv/kernel/module.c:23:27: note: format string is defined here
arch/riscv/kernel/module.c: In function 'apply_r_riscv_pcrel_hi20_rela':
./include/linux/kern_levels.h:5:18: warning: format '%llx' expects argument of type 'long long unsigned int', but argument 3 has type 'Elf32_Addr' {aka 'unsigned int'} [-Wformat=]
arch/riscv/kernel/module.c:104:23: note: format string is defined here
arch/riscv/kernel/module.c: In function 'apply_r_riscv_hi20_rela':
./include/linux/kern_levels.h:5:18: warning: format '%llx' expects argument of type 'long long unsigned int', but argument 3 has type 'Elf32_Addr' {aka 'unsigned int'} [-Wformat=]
arch/riscv/kernel/module.c:146:23: note: format string is defined here
arch/riscv/kernel/module.c: In function 'apply_r_riscv_got_hi20_rela':
./include/linux/kern_levels.h:5:18: warning: format '%llx' expects argument of type 'long long unsigned int', but argument 3 has type 'Elf32_Addr' {aka 'unsigned int'} [-Wformat=]
arch/riscv/kernel/module.c:190:60: note: format string is defined here
arch/riscv/kernel/module.c: In function 'apply_r_riscv_call_plt_rela':
./include/linux/kern_levels.h:5:18: warning: format '%llx' expects argument of type 'long long unsigned int', but argument 3 has type 'Elf32_Addr' {aka 'unsigned int'} [-Wformat=]
arch/riscv/kernel/module.c:214:24: note: format string is defined here
arch/riscv/kernel/module.c: In function 'apply_r_riscv_call_rela':
./include/linux/kern_levels.h:5:18: warning: format '%llx' expects argument of type 'long long unsigned int', but argument 3 has type 'Elf32_Addr' {aka 'unsigned int'} [-Wformat=]
arch/riscv/kernel/module.c:236:23: note: format string is defined here
Signed-off-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NPalmer Dabbelt <palmer@sifive.com>

Fixes the following build error from tinyconfig:

riscv64-unknown-linux-gnu-ld: kernel/sched/fair.o: in function `.L8':
fair.c:(.text+0x70): undefined reference to `__lshrti3'
riscv64-unknown-linux-gnu-ld: kernel/time/clocksource.o: in function `.L0 ':
clocksource.c:(.text+0x334): undefined reference to `__lshrti3'

Fixes: 7f47c73b ("RISC-V: Build tishift only on 64-bit")
Signed-off-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NPalmer Dabbelt <palmer@sifive.com>

Building kernel 4.20 for Fedora as RPM fails, because riscv is missing
vdso_install target in arch/riscv/Makefile.
Signed-off-by: NDavid Abdurachmanov <david.abdurachmanov@gmail.com>
Signed-off-by: NPalmer Dabbelt <palmer@sifive.com>

Replace 8 spaces with tab to match styling.
Signed-off-by: NDavid Abdurachmanov <david.abdurachmanov@gmail.com>
Signed-off-by: NPalmer Dabbelt <palmer@sifive.com>

The printk timestamps are very useful information to visually see
where kernel is spending time during boot. It also helps us see
the timing of hotplug events at runtime.

This patch enables printk timestamps in RISC-V defconfig so that
we have it enabled by default (similar to other architectures
such as x86_64, arm64, etc).
Signed-off-by: NAnup Patel <anup@brainfault.org>
Acked-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NPalmer Dabbelt <palmer@sifive.com>

In vfp_preserve_user_clear_hwstate, ufp_exc->fpinst2 gets assigned to
itself. It should actually be hwstate->fpinst2 that gets assigned to the
ufp_exc field.

Fixes commit 3aa2df6e ("ARM: 8791/1:
vfp: use __copy_to_user() when saving VFP state").
Reported-by: NDavid Binderman <dcb314@hotmail.com>
Signed-off-by: NJulien Thierry <julien.thierry@arm.com>
Signed-off-by: NRussell King <rmk+kernel@armlinux.org.uk>

Since commit ff17fa56 ("d_invalidate(): unhash immediately")
immediately unhashes the dentry, we'll never return the mountpoint in
lookup_mountpoint(), which can lead to an unbreakable loop in
d_invalidate().

I have reports of NFS clients getting into this condition after the server
removes an export of an existing mount created through follow_automount(),
but I suspect there are various other ways to produce this problem if we
hunt down users of d_invalidate().  For example, it is possible to get into
this state by using XFS' d_invalidate() call in xfs_vn_unlink():

truncate -s 100m img{1,2}

mkfs.xfs -q -n version=ci img1
mkfs.xfs -q -n version=ci img2

mkdir -p /mnt/xfs
mount img1 /mnt/xfs

mkdir /mnt/xfs/sub1
mount img2 /mnt/xfs/sub1

cat > /mnt/xfs/sub1/foo &
umount -l /mnt/xfs/sub1
mount img2 /mnt/xfs/sub1

mount --make-private /mnt/xfs

mkdir /mnt/xfs/sub2
mount --move /mnt/xfs/sub1 /mnt/xfs/sub2
rmdir /mnt/xfs/sub1

Fix this by moving the check for an unlinked dentry out of the
detach_mounts() path.

Fixes: ff17fa56 ("d_invalidate(): unhash immediately")
Cc: stable@vger.kernel.org
Reviewed-by: N"Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NBenjamin Coddington <bcodding@redhat.com>
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>

Pull networking fixes from David Miller:
 "One last pull request before heading to Vancouver for LPC, here we have:

   1) Don't forget to free VSI contexts during ice driver unload, from
      Victor Raj.

   2) Don't forget napi delete calls during device remove in ice driver,
      from Dave Ertman.

   3) Don't request VLAN tag insertion of ibmvnic device when SKB
      doesn't have VLAN tags at all.

   4) IPV4 frag handling code has to accomodate the situation where two
      threads try to insert the same fragment into the hash table at the
      same time. From Eric Dumazet.

   5) Relatedly, don't flow separate on protocol ports for fragmented
      frames, also from Eric Dumazet.

   6) Memory leaks in qed driver, from Denis Bolotin.

   7) Correct valid MTU range in smsc95xx driver, from Stefan Wahren.

   8) Validate cls_flower nested policies properly, from Jakub Kicinski.

   9) Clearing of stats counters in mc88e6xxx driver doesn't retain
      important bits in the G1_STATS_OP register causing the chip to
      hang. Fix from Andrew Lunn"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (41 commits)
  act_mirred: clear skb->tstamp on redirect
  net: dsa: mv88e6xxx: Fix clearing of stats counters
  tipc: fix link re-establish failure
  net: sched: cls_flower: validate nested enc_opts_policy to avoid warning
  net: mvneta: correct typo
  flow_dissector: do not dissect l4 ports for fragments
  net: qualcomm: rmnet: Fix incorrect assignment of real_dev
  net: aquantia: allow rx checksum offload configuration
  net: aquantia: invalid checksumm offload implementation
  net: aquantia: fixed enable unicast on 32 macvlan
  net: aquantia: fix potential IOMMU fault after driver unbind
  net: aquantia: synchronized flow control between mac/phy
  net: smsc95xx: Fix MTU range
  net: stmmac: Fix RX packet size > 8191
  qed: Fix potential memory corruption
  qed: Fix SPQ entries not returned to pool in error flows
  qed: Fix blocking/unlimited SPQ entries leak
  qed: Fix memory/entry leak in qed_init_sp_request()
  inet: frags: better deal with smp races
  net: hns3: bugfix for not checking return value
  ...

Merge tag 'kbuild-fixes-v4.20' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild fixes from Masahiro Yamada:

 - fix build errors in binrpm-pkg and bindeb-pkg targets

 - fix false positive matches in merge_config.sh

 - fix build version mismatch in deb-pkg target

 - fix dtbs_install handling in (bin)deb-pkg target

 - revert a commit that allows setlocalversion to write to source tree

* tag 'kbuild-fixes-v4.20' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  builddeb: Fix inclusion of dtbs in debian package
  Revert "scripts/setlocalversion: git: Make -dirty check more robust"
  kbuild: deb-pkg: fix too low build version number
  kconfig: merge_config: avoid false positive matches from comment lines
  kbuild: deb-pkg: fix bindeb-pkg breakage when O= is used
  kbuild: rpm-pkg: fix binrpm-pkg breakage when O= is used

Pull btrfs fixes from David Sterba:
 "Several fixes to recent release (4.19, fixes tagged for stable) and
  other fixes"

* tag 'for-4.20-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  Btrfs: fix missing delayed iputs on unmount
  Btrfs: fix data corruption due to cloning of eof block
  Btrfs: fix infinite loop on inode eviction after deduplication of eof block
  Btrfs: fix deadlock on tree root leaf when finding free extent
  btrfs: avoid link error with CONFIG_NO_AUTO_INLINE
  btrfs: tree-checker: Fix misleading group system information
  Btrfs: fix missing data checksums after a ranged fsync (msync)
  btrfs: fix pinned underflow after transaction aborted
  Btrfs: fix cur_offset in the error case for nocow

Pull ext4 fixes from Ted Ts'o:
 "A large number of ext4 bug fixes, mostly buffer and memory leaks on
  error return cleanup paths"

* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: missing !bh check in ext4_xattr_inode_write()
  ext4: fix buffer leak in __ext4_read_dirblock() on error path
  ext4: fix buffer leak in ext4_expand_extra_isize_ea() on error path
  ext4: fix buffer leak in ext4_xattr_move_to_block() on error path
  ext4: release bs.bh before re-using in ext4_xattr_block_find()
  ext4: fix buffer leak in ext4_xattr_get_block() on error path
  ext4: fix possible leak of s_journal_flag_rwsem in error path
  ext4: fix possible leak of sbi->s_group_desc_leak in error path
  ext4: remove unneeded brelse call in ext4_xattr_inode_update_ref()
  ext4: avoid possible double brelse() in add_new_gdb() on error path
  ext4: avoid buffer leak in ext4_orphan_add() after prior errors
  ext4: avoid buffer leak on shutdown in ext4_mark_iloc_dirty()
  ext4: fix possible inode leak in the retry loop of ext4_resize_fs()
  ext4: fix missing cleanup if ext4_alloc_flex_bg_array() fails while resizing
  ext4: add missing brelse() update_backups()'s error path
  ext4: add missing brelse() add_new_gdb_meta_bg()'s error path
  ext4: add missing brelse() in set_flexbg_block_bitmap()'s error path
  ext4: avoid potential extra brelse in setup_new_flex_group_blocks()

Pull x86 fixes from Thomas Gleixner:
 "A set of x86 fixes:

   - Cure the LDT remapping to user space on 5 level paging which ended
     up in the KASLR space

   - Remove LDT mapping before freeing the LDT pages

   - Make NFIT MCE handling more robust

   - Unbreak the VSMP build by removing the dependency on paravirt ops

   - Support broken PIT emulation on Microsoft hyperV

   - Don't trace vmware_sched_clock() to avoid tracer recursion

   - Remove -pipe from KBUILD CFLAGS which breaks clang and is also
     slower on GCC

   - Trivial coding style and typo fixes"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/cpu/vmware: Do not trace vmware_sched_clock()
  x86/vsmp: Remove dependency on pv_irq_ops
  x86/ldt: Remove unused variable in map_ldt_struct()
  x86/ldt: Unmap PTEs for the slot before freeing LDT pages
  x86/mm: Move LDT remap out of KASLR region on 5-level paging
  acpi/nfit, x86/mce: Validate a MCE's address before using it
  acpi/nfit, x86/mce: Handle only uncorrectable machine checks
  x86/build: Remove -pipe from KBUILD_CFLAGS
  x86/hyper-v: Fix indentation in hv_do_fast_hypercall16()
  Documentation/x86: Fix typo in zero-page.txt
  x86/hyper-v: Enable PIT shutdown quirk
  clockevents/drivers/i8253: Add support for PIT shutdown quirk

Pull perf fixes from Thomas Gleixner:
 "A bunch of perf tooling fixes:

   - Make the Intel PT SQL viewer more robust

   - Make the Intel PT debug log more useful

   - Support weak groups in perf record so it's behaving the same way as
     perf stat

   - Display the LBR stats in callchain entries properly in perf top

   - Handle different PMu names with common prefix properlin in pert
     stat

   - Start syscall augmenting in perf trace. Preparation for
     architecture independent eBPF instrumentation of syscalls.

   - Fix build breakage in JVMTI perf lib

   - Fix arm64 tools build failure wrt smp_load_{acquire,release}"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf tools: Do not zero sample_id_all for group members
  perf tools: Fix undefined symbol scnprintf in libperf-jvmti.so
  perf beauty: Use SRCARCH, ARCH=x86_64 must map to "x86" to find the headers
  perf intel-pt: Add MTC and CYC timestamps to debug log
  perf intel-pt: Add more event information to debug log
  perf scripts python: exported-sql-viewer.py: Fix table find when table re-ordered
  perf scripts python: exported-sql-viewer.py: Add help window
  perf scripts python: exported-sql-viewer.py: Add Selected branches report
  perf scripts python: exported-sql-viewer.py: Fall back to /usr/local/lib/libxed.so
  perf top: Display the LBR stats in callchain entry
  perf stat: Handle different PMU names with common prefix
  perf record: Support weak groups
  perf evlist: Move perf_evsel__reset_weak_group into evlist
  perf augmented_syscalls: Start collecting pathnames in the BPF program
  perf trace: Fix setting of augmented payload when using eBPF + raw_syscalls
  perf trace: When augmenting raw_syscalls plug raw_syscalls:sys_exit too
  perf examples bpf: Start augmenting raw_syscalls:sys_{start,exit}
  tools headers barrier: Fix arm64 tools build failure wrt smp_load_{acquire,release}

Pull timer fix from Thomas Gleixner:
 "Just the removal of a redundant call into the sched deadline overrun
  check"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  posix-cpu-timers: Remove useless call to check_dl_overrun()