Commit Graph

17498 Commits

Author SHA1 Message Date
Linus Torvalds 7bcd342594 Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq updates from Thomas Gleixner:
 "A rather small set of irq updates this time:

   - removal of the old and now obsolete irq domain debugging code

   - the new Goldfish PIC driver

   - the usual pile of small fixes and updates"

* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqdomain: Kill CONFIG_IRQ_DOMAIN_DEBUG
  irq/work: Improve the flag definitions
  irqchip/gic-v3: Fix the driver probe() fail due to disabled GICC entry
  irqchip/irq-goldfish-pic: Add Goldfish PIC driver
  dt-bindings/goldfish-pic: Add device tree binding for Goldfish PIC driver
  irqchip/ompic: fix return value check in ompic_of_init()
  dt-bindings/bcm283x: Define polarity of per-cpu interrupts
  irqchip/irq-bcm2836: Add support for DT interrupt polarity
  dt-bindings/bcm2836-l1-intc: Add interrupt polarity support
2018-01-29 16:47:21 -08:00
Linus Torvalds 49f9c3552c init_task out-of-lining
-----BEGIN PGP SIGNATURE-----
 
 iQIVAwUAWl80tvSw1s6N8H32AQJq8A//ViRN5fExrd678Eh2Bz1ytrJYMUfYY3Hv
 QTH5TH9zFyLFyWLB1Iwe13sdLVTTM88O0qcDb54Lx9fWUqeMZyYvBhLtWPc00lTU
 0m3EyYR87MFWaEV+VxaVWgWaWkMDkd39KubDitcS+YIBDszTuMpYodhPUsgLt7lr
 pePX7eurXKdQPTh4NUOjGA2NaZot3tga76J6D8NKruGYUstQCGxpP1ryiFfACnwf
 NLWNO8ZBMtlDwX1mHYOOMFMaBzFzXorPm7jY4HJDf3mUM84xI3ach6CuH9RTSzfq
 A+qB1U3QILPVFo2HtqOHui4bFjRwqOf6uIrI/KcnioJ37w1O+KFcMJeDnX2I211q
 f2lXehJLQA7kPmxQw8T3//HDRaLXc0Qxt7IPZRFinrlkcN4oh3DD5euMfCFBSoZG
 PTbjxlgMfzJPoZtqAcy0rV5L54a/F4h915OQPJCKLwujIsXD2nT993vNmGDyq4zh
 BzNMxSXJC8p+jYvQpNhWyyxwDBBT/YsVQo/ACwg4eJnD3blVTAioRT9ZZcAcsY0F
 0z1eWW5RiknzIaXQWvjfK0gYKpO+aMSu9+gipHfMbU3yXG+sPj/H6zAHYzqX3uQZ
 jb5Iujjnu49W/YD+RiMenuu59lNXUnLSeRnlV7dw0qxGK1FzGo24+ZzKFhJhKvzG
 tdfUsev1Mc8=
 =jhWg
 -----END PGP SIGNATURE-----

Merge tag 'init_task-20180117' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

Pull init_task initializer cleanups from David Howells:
 "It doesn't seem useful to have the init_task in a header file rather
  than in a normal source file. We could consolidate init_task handling
  instead and expand out various macros.

  Here's a series of patches that consolidate init_task handling:

   (1) Make THREAD_SIZE available to vmlinux.lds for cris, hexagon and
       openrisc.

   (2) Alter the INIT_TASK_DATA linker script macro to set
       init_thread_union and init_stack rather than defining these in C.

       Insert init_task and init_thread_into into the init_stack area in
       the linker script as appropriate to the configuration, with
       different section markers so that they end up correctly ordered.

       We can then get merge ia64's init_task.c into the main one.

       We then have a bunch of single-use INIT_*() macros that seem only
       to be macros because they used to be used per-arch. We can then
       expand these in place of the user and get rid of a few lines and
       a lot of backslashes.

   (3) Expand INIT_TASK() in place.

   (4) Expand in place various small INIT_*() macros that are defined
       conditionally. Expand them and surround them by #if[n]def/#endif
       in the .c file as it takes fewer lines.

   (5) Expand INIT_SIGNALS() and INIT_SIGHAND() in place.

   (6) Expand INIT_STRUCT_PID in place.

  These macros can then be discarded"

* tag 'init_task-20180117' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
  Expand INIT_STRUCT_PID and remove
  Expand the INIT_SIGNALS and INIT_SIGHAND macros and remove
  Expand various INIT_* macros and remove
  Expand INIT_TASK() in init/init_task.c and remove
  Construct init thread stack in the linker script rather than by union
  openrisc: Make THREAD_SIZE available to vmlinux.lds
  hexagon: Make THREAD_SIZE available to vmlinux.lds
  cris: Make THREAD_SIZE available to vmlinux.lds
2018-01-29 09:08:34 -08:00
Marc Zyngier c5baa1be8f irqdomain: Kill CONFIG_IRQ_DOMAIN_DEBUG
CONFIG_IRQ_DOMAIN_DEBUG is similar to CONFIG_GENERIC_IRQ_DEBUGFS,
just with less information.

Spring cleanup time.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Yang Shunyong <shunyong.yang@hxt-semitech.com>
Link: https://lkml.kernel.org/r/20180117142647.23622-1-marc.zyngier@arm.com
2018-01-24 12:32:58 +01:00
Linus Torvalds 24b6124047 KVM fixes for v4.15-rc9
ARM:
 * fix incorrect huge page mappings on systems using the contiguous hint
   for hugetlbfs
 * support alternative GICv4 init sequence
 * correctly implement the ARM SMCC for HVC and SMC handling
 
 PPC:
 * add KVM IOCTL for reporting vulnerability and workaround status
 
 s390:
 * provide userspace interface for branch prediction changes in firmware
 
 x86:
 * use correct macros for bits
 -----BEGIN PGP SIGNATURE-----
 
 iQEcBAABCAAGBQJaY3/eAAoJEED/6hsPKofo64kH/16SCSA9pKJTf39+jLoCPzbp
 tlhzxoaqb9cPNMQBAk8Cj5xNJ6V4Clwnk8iRWaE6dRI5nWQxnxRHiWxnrobHwUbK
 I0zSy+SywynSBnollKzLzQrDUBZ72fv3oLwiYEYhjMvs0zW6Q/vg10WERbav912Q
 bv8nb5e8TbvU500ErndKTXOa8/B6uZYkMVjBNvAHwb+4AQ7bJgDQs5/qOeXllm8A
 MT/SNYop/fkjRP7mQng5XYzoO+70tbe0hWpOQGgBnduzrbkNNvZtYtovusHYytLX
 PAB7DDPbLZm5L2HBo4zvKgTHIoHTxU0X2yfUDzt7O151O2WSyqBRC3y1tpj6xa8=
 =GnNJ
 -----END PGP SIGNATURE-----

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM fixes from Radim Krčmář:
 "ARM:
   - fix incorrect huge page mappings on systems using the contiguous
     hint for hugetlbfs
   - support alternative GICv4 init sequence
   - correctly implement the ARM SMCC for HVC and SMC handling

  PPC:
   - add KVM IOCTL for reporting vulnerability and workaround status

  s390:
   - provide userspace interface for branch prediction changes in
     firmware

  x86:
   - use correct macros for bits"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: s390: wire up bpb feature
  KVM: PPC: Book3S: Provide information about hardware/firmware CVE workarounds
  KVM/x86: Fix wrong macro references of X86_CR0_PG_BIT and X86_CR4_PAE_BIT in kvm_valid_sregs()
  arm64: KVM: Fix SMCCC handling of unimplemented SMC/HVC calls
  KVM: arm64: Fix GICv4 init when called from vgic_its_create
  KVM: arm/arm64: Check pagesize when allocating a hugepage at Stage 2
2018-01-20 11:41:09 -08:00
Linus Torvalds 4917d5df38 powerpc fixes for 4.15 #8
More than we'd like after rc8, but nothing very alarming either, just tying up
 loose ends before the release:
 
 Since we changed powernv to use cpufreq_get() from show_cpuinfo(), we see
 warnings with PREEMPT enabled. But the preempt_disable() in show_cpuinfo()
 doesn't actually prevent CPU hotplug as it suggests, so remove it.
 
 Two updates to the recently merged RFI flush code. Wire up the generic sysfs
 file to report the status, and add a debugfs file to allow enabling/disabling it
 at runtime.
 
 Two updates to xmon, one to add the RFI flush related fields to the paca dump,
 and another to not use hashed pointers in the paca dump.
 
 And one minor fix to add a missing include of linux/types.h in asm/hvcall.h, not
 seen to break the build in upstream, but correct anyway.
 
 Thanks to:
   Benjamin Herrenschmidt, Michal Suchanek, Nicholas Piggin.
 -----BEGIN PGP SIGNATURE-----
 
 iQIwBAABCAAaBQJaYcINExxtcGVAZWxsZXJtYW4uaWQuYXUACgkQUevqPMjhpYDQ
 /w//S5OeowmRncTPsiCNlZSLlGsynE7/3QiB3qS0+hGK9vzcdl9Zw5nBxPmA16g+
 53z2pgRpsJvagqR3JFHwYsoOKg157heMZKbrFyV/EWXPUoZQD8Iko88BkNQfV9kH
 dZM4gOuPnn7lLJQJrdc13SRwlOlc1oqOiPqFQtwH5CTlH/I4kVe3iR+oaReA71+U
 bKZQWwXjRqjexLgxfPhaMH9CzfgK6LpM/TEc2tG1YBbKxbTCbXeFYhrNFvLKILHg
 sC/8QDYzFbdgqTrcw6rXpwoxA65Eu8I3puOLpTl/oJ/OQZZBLN6sjjJ33+Aq1yNR
 cXOakJgC+WjNYmw0C2eRBttMG1o0t/g52C9e0DWN2cXU9nwZ5mdFtbQos1kOdaLv
 V5sOpX6HH0+K8jefvw9qdmx4+kma38nyBY1hlsSXkMG5FwXVOx5V/hLFdH4zJs4+
 /9q3Bnwklc7X7Y+Qvqz/5rwi2T4++cIQpngRE2B7uUwjqNQR/iQUrXcb1MBie8LB
 RO7JD8D0ut+Utj75/b6PmBh2tvIHjWvC8BY9mexGfYgU4e/kHbpUa0tN8/OZhYv2
 pm1LP7Qiq+Lt8ii9UjvRKRdXWuxP/8dZ5EI7l7DJkwDItHTzQCDnfCRYjLqvXuDQ
 CGSsyMpQzzReWhWHDn4WJp4f8wRqDyN24d2a95ozaY7HJ4M=
 =zgy0
 -----END PGP SIGNATURE-----

Merge tag 'powerpc-4.15-8' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc fixes from Michael Ellerman:
 "More than we'd like after rc8, but nothing very alarming either, just
  tying up loose ends before the release:

  Since we changed powernv to use cpufreq_get() from show_cpuinfo(), we
  see warnings with PREEMPT enabled. But the preempt_disable() in
  show_cpuinfo() doesn't actually prevent CPU hotplug as it suggests, so
  remove it.

  Two updates to the recently merged RFI flush code. Wire up the generic
  sysfs file to report the status, and add a debugfs file to allow
  enabling/disabling it at runtime.

  Two updates to xmon, one to add the RFI flush related fields to the
  paca dump, and another to not use hashed pointers in the paca dump.

  And one minor fix to add a missing include of linux/types.h in
  asm/hvcall.h, not seen to break the build in upstream, but correct
  anyway.

  Thanks to: Benjamin Herrenschmidt, Michal Suchanek, Nicholas Piggin"

* tag 'powerpc-4.15-8' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/pseries: include linux/types.h in asm/hvcall.h
  powerpc/64s: Allow control of RFI flush via debugfs
  powerpc/64s: Wire up cpu_show_meltdown()
  powerpc: Don't preempt_disable() in show_cpuinfo()
  powerpc/xmon: Don't print hashed pointers in paca dump
  powerpc/xmon: Add RFI flush related fields to paca dump
2018-01-19 11:19:11 -08:00
Paul Mackerras 3214d01f13 KVM: PPC: Book3S: Provide information about hardware/firmware CVE workarounds
This adds a new ioctl, KVM_PPC_GET_CPU_CHAR, that gives userspace
information about the underlying machine's level of vulnerability
to the recently announced vulnerabilities CVE-2017-5715,
CVE-2017-5753 and CVE-2017-5754, and whether the machine provides
instructions to assist software to work around the vulnerabilities.

The ioctl returns two u64 words describing characteristics of the
CPU and required software behaviour respectively, plus two mask
words which indicate which bits have been filled in by the kernel,
for extensibility.  The bit definitions are the same as for the
new H_GET_CPU_CHARACTERISTICS hypercall.

There is also a new capability, KVM_CAP_PPC_GET_CPU_CHAR, which
indicates whether the new ioctl is available.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-01-19 15:17:01 +11:00
Michal Suchanek 1b689a95ce powerpc/pseries: include linux/types.h in asm/hvcall.h
Commit 6e032b350c ("powerpc/powernv: Check device-tree for RFI flush
settings") uses u64 in asm/hvcall.h without including linux/types.h

This breaks hvcall.h users that do not include the header themselves.

Fixes: 6e032b350c ("powerpc/powernv: Check device-tree for RFI flush settings")
Signed-off-by: Michal Suchanek <msuchanek@suse.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-17 23:30:46 +11:00
Michael Ellerman 236003e6b5 powerpc/64s: Allow control of RFI flush via debugfs
Expose the state of the RFI flush (enabled/disabled) via debugfs, and
allow it to be enabled/disabled at runtime.

eg: $ cat /sys/kernel/debug/powerpc/rfi_flush
    1
    $ echo 0 > /sys/kernel/debug/powerpc/rfi_flush
    $ cat /sys/kernel/debug/powerpc/rfi_flush
    0

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
2018-01-17 23:30:21 +11:00
Michael Ellerman fd6e440f20 powerpc/64s: Wire up cpu_show_meltdown()
The recent commit 87590ce6e3 ("sysfs/cpu: Add vulnerability folder")
added a generic folder and set of files for reporting information on
CPU vulnerabilities. One of those was for meltdown:

  /sys/devices/system/cpu/vulnerabilities/meltdown

This commit wires up that file for 64-bit Book3S powerpc.

For now we default to "Vulnerable" unless the RFI flush is enabled.
That may not actually be true on all hardware, further patches will
refine the reporting based on the CPU/platform etc. But for now we
default to being pessimists.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-17 23:30:20 +11:00
Linus Torvalds 6bb821193b powerpc fixes for 4.15 #7
One fix for an oops at boot if we take a hotplug interrupt before we are ready
 to handle it.
 
 The bulk is patches to implement mitigation for Meltdown, see the change logs
 for more details.
 
 Thanks to:
   Nicholas Piggin, Michael Neuling, Oliver O'Halloran, Jon Masters, Jose Ricardo
   Ziviani, David Gibson.
 -----BEGIN PGP SIGNATURE-----
 
 iQIwBAABCAAaBQJaWXZ+ExxtcGVAZWxsZXJtYW4uaWQuYXUACgkQUevqPMjhpYBe
 ew/+KMp80VAIGSyFeYHLg8oClnQjKcEDMzlNoHo8WU6NwwNzk2XXBXNaGT7Osg7B
 Ny69R3/VRrGmi/2uule9OzF2eZt8BUmRn3cHDcUB5OwFjMysv4M2jc+OK0STQxLU
 F769rX+ZlkyAvQn4UxtNCUob+JDfVbE5Lurrx475ZGL1YHk6QqBGhlN/niXKtkBz
 upeBEpu4JgwsLLD9H7c4QQha9PkhxY51jtvxL24cgwDuKJKhTdxLahPlA3QmLafu
 FJxR9R0YzTj9Ivuae5yM7xRKr5wROTPtTRbG9sN7XOgFNrQ+LSgemXGrlV/fzdhV
 6iPn2hHs4bu45SOIM+Hhf7OwHTtnMetXmKo6NldlKHVCw1HwBLigRohnOTPjiHfZ
 P6brR4T/cglakBiE29+8T0UFqOPizEJiQRHnsoWzwIa/aTqCGEE3m3rgTxU6ovt5
 3JggC51ZRDFsjGvj+JFnxGxCjYC4tDbfBI28M+GuWZZPBKLkFnEk8PlSzYyHPW2p
 5uVA/UN4KHVGYUfJVUC+LMP+ZIOSEyEISKk7RuK0C0mwHSXcvxbeEefXbc18Xjai
 J/pl/c9/4CRnEbdPm305xBxKKmU6gWxWRK3KbRFsoTI/wp+Ryx5TjPpgAa5GnaLv
 nrtrfKs8skWfGMoDWH7+KILt0fgRR2x+91GTSxc5aaHtYBI=
 =UZHv
 -----END PGP SIGNATURE-----

Merge tag 'powerpc-4.15-7' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc fixes from Michael Ellerman:
 "One fix for an oops at boot if we take a hotplug interrupt before we
  are ready to handle it.

  The bulk is patches to implement mitigation for Meltdown, see the
  change logs for more details.

  Thanks to: Nicholas Piggin, Michael Neuling, Oliver O'Halloran, Jon
  Masters, Jose Ricardo Ziviani, David Gibson"

* tag 'powerpc-4.15-7' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/powernv: Check device-tree for RFI flush settings
  powerpc/pseries: Query hypervisor for RFI flush settings
  powerpc/64s: Support disabling RFI flush with no_rfi_flush and nopti
  powerpc/64s: Add support for RFI flush of L1-D cache
  powerpc/64s: Convert slb_miss_common to use RFI_TO_USER/KERNEL
  powerpc/64: Convert fast_exception_return to use RFI_TO_USER/KERNEL
  powerpc/64: Convert the syscall exit path to use RFI_TO_USER/KERNEL
  powerpc/64s: Simple RFI macro conversions
  powerpc/64: Add macros for annotating the destination of rfid/hrfid
  powerpc/pseries: Add H_GET_CPU_CHARACTERISTICS flags & wrapper
  powerpc/pseries: Make RAS IRQ explicitly dependent on DLPAR WQ
2018-01-14 15:03:17 -08:00
Paolo Bonzini 0217690f88 PPC KVM fixes for 4.15
Four commits here, including two that were tagged but never merged.
 Three of them are for the HPT resizing code; two of those fix a
 user-triggerable use-after-free in the host, and one that fixes
 stale TLB entries in the guest.  The remaining commit fixes a bug
 causing PR KVM guests under PowerVM to fail to start.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQEcBAABAgAGBQJaVfPgAAoJEJ2a6ncsY3GfA10IANZMkwtIpqxGlsAeXKr5bWdl
 iXYD9ymb2/FOHBbg6v8Eh6Gb1ycjzXpXqn74/Y9TE4Ort7mdiH+W6kXYEsMqL8yg
 7Uwnj8DuWFuFxX0x0V4SJQzgdCnOefVcfoo/RnLUzmLsW0Vqtr3A1djM5iHlxFvv
 ntkNtGYPOoaHl6rjtfHTDfLWN/DzEJbaIU/0O1LIkBxPG4STzSXErAucLL46Pa/X
 NuPO2HfpxQiacHVG62iy89eJeAcraEAXnH5e6eVPRQQqh3DSIERMU6n6jXyZeMU5
 NWX8Qme3VGBpiJOiCGMvMrnJmQmMTSWTtkGljyaFy+vZWMqGZ6xJ3wIP+5t9d+Q=
 =dw6K
 -----END PGP SIGNATURE-----

Merge tag 'kvm-ppc-fixes-4.15-3' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc into kvm-master

PPC KVM fixes for 4.15

Four commits here, including two that were tagged but never merged.
Three of them are for the HPT resizing code; two of those fix a
user-triggerable use-after-free in the host, and one that fixes
stale TLB entries in the guest.  The remaining commit fixes a bug
causing PR KVM guests under PowerVM to fail to start.
2018-01-11 14:07:27 +01:00
Benjamin Herrenschmidt 349524bc0d powerpc: Don't preempt_disable() in show_cpuinfo()
This causes warnings from cpufreq mutex code. This is also rather
unnecessary and ineffective. If we really want to prevent concurrent
unplug, we could take the unplug read lock but I don't see this being
critical.

Fixes: cd77b5ce20 ("powerpc/powernv/cpufreq: Fix the frequency read by /proc/cpuinfo")
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-11 01:36:50 +11:00
Michael Ellerman 2248fade96 powerpc/xmon: Don't print hashed pointers in paca dump
Remember when the biggest problem we had to worry about was hashed
pointers, those were the days.

These were missed in my earlier patch because they don't match "%p",
but the macro is hiding a "%p", so these all end up being hashed,
which is not what we want in xmon. Convert them to "%px".

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-11 01:17:24 +11:00
Michael Ellerman 274920a3ec powerpc/xmon: Add RFI flush related fields to paca dump
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-11 00:10:50 +11:00
Oliver O'Halloran 6e032b350c powerpc/powernv: Check device-tree for RFI flush settings
New device-tree properties are available which tell the hypervisor
settings related to the RFI flush. Use them to determine the
appropriate flush instruction to use, and whether the flush is
required.

Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-10 21:27:16 +11:00
Michael Neuling 8989d56878 powerpc/pseries: Query hypervisor for RFI flush settings
A new hypervisor call is available which tells the guest settings
related to the RFI flush. Use it to query the appropriate flush
instruction(s), and whether the flush is required.

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-10 21:27:15 +11:00
Michael Ellerman bc9c9304a4 powerpc/64s: Support disabling RFI flush with no_rfi_flush and nopti
Because there may be some performance overhead of the RFI flush, add
kernel command line options to disable it.

We add a sensibly named 'no_rfi_flush' option, but we also hijack the
x86 option 'nopti'. The RFI flush is not the same as KPTI, but if we
see 'nopti' we can guess that the user is trying to avoid any overhead
of Meltdown mitigations, and it means we don't have to educate every
one about a different command line option.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-10 21:27:15 +11:00
Michael Ellerman aa8a5e0062 powerpc/64s: Add support for RFI flush of L1-D cache
On some CPUs we can prevent the Meltdown vulnerability by flushing the
L1-D cache on exit from kernel to user mode, and from hypervisor to
guest.

This is known to be the case on at least Power7, Power8 and Power9. At
this time we do not know the status of the vulnerability on other CPUs
such as the 970 (Apple G5), pasemi CPUs (AmigaOne X1000) or Freescale
CPUs. As more information comes to light we can enable this, or other
mechanisms on those CPUs.

The vulnerability occurs when the load of an architecturally
inaccessible memory region (eg. userspace load of kernel memory) is
speculatively executed to the point where its result can influence the
address of a subsequent speculatively executed load.

In order for that to happen, the first load must hit in the L1,
because before the load is sent to the L2 the permission check is
performed. Therefore if no kernel addresses hit in the L1 the
vulnerability can not occur. We can ensure that is the case by
flushing the L1 whenever we return to userspace. Similarly for
hypervisor vs guest.

In order to flush the L1-D cache on exit, we add a section of nops at
each (h)rfi location that returns to a lower privileged context, and
patch that with some sequence. Newer firmwares are able to advertise
to us that there is a special nop instruction that flushes the L1-D.
If we do not see that advertised, we fall back to doing a displacement
flush in software.

For guest kernels we support migration between some CPU versions, and
different CPUs may use different flush instructions. So that we are
prepared to migrate to a machine with a different flush instruction
activated, we may have to patch more than one flush instruction at
boot if the hypervisor tells us to.

In the end this patch is mostly the work of Nicholas Piggin and
Michael Ellerman. However a cast of thousands contributed to analysis
of the issue, earlier versions of the patch, back ports testing etc.
Many thanks to all of them.

Tested-by: Jon Masters <jcm@redhat.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-10 21:27:06 +11:00
David Gibson ecba8297aa KVM: PPC: Book3S HV: Always flush TLB in kvmppc_alloc_reset_hpt()
The KVM_PPC_ALLOCATE_HTAB ioctl(), implemented by kvmppc_alloc_reset_hpt()
is supposed to completely clear and reset a guest's Hashed Page Table (HPT)
allocating or re-allocating it if necessary.

In the case where an HPT of the right size already exists and it just
zeroes it, it forces a TLB flush on all guest CPUs, to remove any stale TLB
entries loaded from the old HPT.

However, that situation can arise when the HPT is resizing as well - or
even when switching from an RPT to HPT - so those cases need a TLB flush as
well.

So, move the TLB flush to trigger in all cases except for errors.

Cc: stable@vger.kernel.org # v4.10+
Fixes: f98a8bf9ee ("KVM: PPC: Book3S HV: Allow KVM_PPC_ALLOCATE_HTAB ioctl() to change HPT size")
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-01-10 20:45:41 +11:00
Alexey Kardashevskiy 6c7d47c33e KVM: PPC: Book3S PR: Fix WIMG handling under pHyp
Commit 96df226 ("KVM: PPC: Book3S PR: Preserve storage control bits")
added code to preserve WIMG bits but it missed 2 special cases:
- a magic page in kvmppc_mmu_book3s_64_xlate() and
- guest real mode in kvmppc_handle_pagefault().

For these ptes, WIMG was 0 and pHyp failed on these causing a guest to
stop in the very beginning at NIP=0x100 (due to bd9166ffe "KVM: PPC:
Book3S PR: Exit KVM on failed mapping").

According to LoPAPR v1.1 14.5.4.1.2 H_ENTER:

 The hypervisor checks that the WIMG bits within the PTE are appropriate
 for the physical page number else H_Parameter return. (For System Memory
 pages WIMG=0010, or, 1110 if the SAO option is enabled, and for IO pages
 WIMG=01**.)

This hence initializes WIMG to non-zero value HPTE_R_M (0x10), as expected
by pHyp.

[paulus@ozlabs.org - fix compile for 32-bit]

Cc: stable@vger.kernel.org # v4.11+
Fixes: 96df226 "KVM: PPC: Book3S PR: Preserve storage control bits"
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Tested-by: Ruediger Oertel <ro@suse.de>
Reviewed-by: Greg Kurz <groug@kaod.org>
Tested-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-01-10 20:45:00 +11:00
David Howells 0500871f21 Construct init thread stack in the linker script rather than by union
Construct the init thread stack in the linker script rather than doing it
by means of a union so that ia64's init_task.c can be got rid of.

The following symbols are then made available from INIT_TASK_DATA() linker
script macro:

	init_thread_union
	init_stack

INIT_TASK_DATA() also expands the region to THREAD_SIZE to accommodate the
size of the init stack.  init_thread_union is given its own section so that
it can be placed into the stack space in the right order.  I'm assuming
that the ia64 ordering is correct and that the task_struct is first and the
thread_info second.

Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Tony Luck <tony.luck@intel.com>
Tested-by: Will Deacon <will.deacon@arm.com> (arm64)
Tested-by: Palmer Dabbelt <palmer@sifive.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
2018-01-09 23:21:02 +00:00
Nicholas Piggin c7305645eb powerpc/64s: Convert slb_miss_common to use RFI_TO_USER/KERNEL
In the SLB miss handler we may be returning to user or kernel. We need
to add a check early on and save the result in the cr4 register, and
then we bifurcate the return path based on that.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-10 03:07:33 +11:00
Nicholas Piggin a08f828cf4 powerpc/64: Convert fast_exception_return to use RFI_TO_USER/KERNEL
Similar to the syscall return path, in fast_exception_return we may be
returning to user or kernel context. We already have a test for that,
because we conditionally restore r13. So use that existing test and
branch, and bifurcate the return based on that.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-10 03:07:32 +11:00
Nicholas Piggin b8e90cb7bc powerpc/64: Convert the syscall exit path to use RFI_TO_USER/KERNEL
In the syscall exit path we may be returning to user or kernel
context. We already have a test for that, because we conditionally
restore r13. So use that existing test and branch, and bifurcate the
return based on that.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-10 03:07:31 +11:00
Nicholas Piggin 222f20f140 powerpc/64s: Simple RFI macro conversions
This commit does simple conversions of rfi/rfid to the new macros that
include the expected destination context. By simple we mean cases
where there is a single well known destination context, and it's
simply a matter of substituting the instruction for the appropriate
macro.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-10 03:07:30 +11:00
Nicholas Piggin 50e51c13b3 powerpc/64: Add macros for annotating the destination of rfid/hrfid
The rfid/hrfid ((Hypervisor) Return From Interrupt) instruction is
used for switching from the kernel to userspace, and from the
hypervisor to the guest kernel. However it can and is also used for
other transitions, eg. from real mode kernel code to virtual mode
kernel code, and it's not always clear from the code what the
destination context is.

To make it clearer when reading the code, add macros which encode the
expected destination context.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-10 03:07:30 +11:00
Michael Ellerman a6978f405d Merge branch 'topic/ppc-kvm' into fixes
Merge the topic branch with share with the kvm-ppc tree. In this case
we need to share the definition of a new hypervisor call and
associated flags.
2018-01-10 02:24:34 +11:00
Michael Neuling 191eccb158 powerpc/pseries: Add H_GET_CPU_CHARACTERISTICS flags & wrapper
A new hypervisor call has been defined to communicate various
characteristics of the CPU to guests. Add definitions for the hcall
number, flags and a wrapper function.

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-10 01:46:34 +11:00
Michael Ellerman e2d5915293 powerpc/pseries: Make RAS IRQ explicitly dependent on DLPAR WQ
The hotplug code uses its own workqueue to handle IRQ requests
(pseries_hp_wq), however that workqueue is initialized after
init_ras_IRQ(). That can lead to a kernel panic if any hotplug
interrupts fire after init_ras_IRQ() but before pseries_hp_wq is
initialised. eg:

  UDP-Lite hash table entries: 2048 (order: 0, 65536 bytes)
  NET: Registered protocol family 1
  Unpacking initramfs...
  (qemu) object_add memory-backend-ram,id=mem1,size=10G
  (qemu) device_add pc-dimm,id=dimm1,memdev=mem1
  Unable to handle kernel paging request for data at address 0xf94d03007c421378
  Faulting instruction address: 0xc00000000012d744
  Oops: Kernel access of bad area, sig: 11 [#1]
  LE SMP NR_CPUS=2048 NUMA pSeries
  Modules linked in:
  CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.15.0-rc2-ziviani+ #26
  task:         (ptrval) task.stack:         (ptrval)
  NIP:  c00000000012d744 LR: c00000000012d744 CTR: 0000000000000000
  REGS:         (ptrval) TRAP: 0380   Not tainted  (4.15.0-rc2-ziviani+)
  MSR:  8000000000009033 <SF,EE,ME,IR,DR,RI,LE>  CR: 28088042  XER: 20040000
  CFAR: c00000000012d3c4 SOFTE: 0
  ...
  NIP [c00000000012d744] __queue_work+0xd4/0x5c0
  LR [c00000000012d744] __queue_work+0xd4/0x5c0
  Call Trace:
  [c0000000fffefb90] [c00000000012d744] __queue_work+0xd4/0x5c0 (unreliable)
  [c0000000fffefc70] [c00000000012dce4] queue_work_on+0xb4/0xf0

This commit makes the RAS IRQ registration explicitly dependent on the
creation of the pseries_hp_wq.

Reported-by: Min Deng <mdeng@redhat.com>
Reported-by: Daniel Henrique Barboza <danielhb@linux.vnet.ibm.com>
Tested-by: Jose Ricardo Ziviani <joserz@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
2018-01-08 14:54:32 +11:00
Linus Torvalds 3219e264b9 powerpc fixes for 4.15 #6
Just one fix to correctly return SEGV_ACCERR when we take a SEGV on a mapped
 region. The bug was introduced in the refactoring of the page fault handler we
 did in the previous release.
 
 Thanks to:
   John Sperbeck.
 -----BEGIN PGP SIGNATURE-----
 
 iQIwBAABCAAaBQJaULvEExxtcGVAZWxsZXJtYW4uaWQuYXUACgkQUevqPMjhpYBN
 hw//W6NeKl1iS7Xf5tcFX97I/TBakl0rS7gHGBMheQT4IGengQ3dJqfCMdq6nfyx
 Sss72UG1sVfeYNG5djJjoZ3hmnt1CjcMkRlQotUhFYACufHYiI8DwYlUTNYpQR6f
 z6uaItK2S5JWSzuk8wOe/VUmBqyIfe+LIWplh8uGy1vn93avbyHrJAAtPFeSyiBm
 TA6EMubY4n1NpNWyGIWBILO7e1yI0xT4jctwNy/ZAGC0lgutFb4sWY/ZxgYlQyKo
 fxb0Al8REpY73IjbZbSzcZ1GfdzDztda1fCNyUeKShRInSJTp31zasn4YCXzYOU8
 8yLw5DcnlA9Fyy7BV0IuFtAfV4wUHS9NDe8ebX6xKXarurTCwugoSbmHCQ8E7jIC
 4FFVhArQdraY+tumOwouJA7g4nGUtGV6rpZAUnd++7xVvFspJiAbFpbU2vUNnnJ4
 VoU2lvWjox9r6wxT001Ct/4M+XoR8+nnEKs8bll1771CyV+AQ4fGqoDga3dOB2cC
 M1ejwLFZ80ZnXDUY6wc4Wzor3G1knVRzuRLEcsoAe4vJunGsS1i9tYce9bOJ9la+
 okcmoPm0roPJSiT1bmiptIAsJRjZZq2cxr2+lBBQ9zlNuZyEIY/CwrBM/0ZP6RJI
 ljbjOCj0xvJBkmIBSenOVO/tIBi/Ww+wL2MDzsYv+K1pp24=
 =VAzk
 -----END PGP SIGNATURE-----

Merge tag 'powerpc-4.15-6' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc fix from Michael Ellerman:
 "Just one fix to correctly return SEGV_ACCERR when we take a SEGV on a
  mapped region. The bug was introduced in the refactoring of the page
  fault handler we did in the previous release.

  Thanks to John Sperbeck"

* tag 'powerpc-4.15-6' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/mm: Fix SEGV on mapped region to return SEGV_ACCERR
2018-01-06 09:48:27 -08:00
John Sperbeck ecb101aed8 powerpc/mm: Fix SEGV on mapped region to return SEGV_ACCERR
The recent refactoring of the powerpc page fault handler in commit
c3350602e8 ("powerpc/mm: Make bad_area* helper functions") caused
access to protected memory regions to indicate SEGV_MAPERR instead of
the traditional SEGV_ACCERR in the si_code field of a user-space
signal handler. This can confuse debug libraries that temporarily
change the protection of memory regions, and expect to use SEGV_ACCERR
as an indication to restore access to a region.

This commit restores the previous behavior. The following program
exhibits the issue:

    $ ./repro read  || echo "FAILED"
    $ ./repro write || echo "FAILED"
    $ ./repro exec  || echo "FAILED"

    #include <stdio.h>
    #include <stdlib.h>
    #include <string.h>
    #include <unistd.h>
    #include <signal.h>
    #include <sys/mman.h>
    #include <assert.h>

    static void segv_handler(int n, siginfo_t *info, void *arg) {
            _exit(info->si_code == SEGV_ACCERR ? 0 : 1);
    }

    int main(int argc, char **argv)
    {
            void *p = NULL;
            struct sigaction act = {
                    .sa_sigaction = segv_handler,
                    .sa_flags = SA_SIGINFO,
            };

            assert(argc == 2);
            p = mmap(NULL, getpagesize(),
                    (strcmp(argv[1], "write") == 0) ? PROT_READ : 0,
                    MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
            assert(p != MAP_FAILED);

            assert(sigaction(SIGSEGV, &act, NULL) == 0);
            if (strcmp(argv[1], "read") == 0)
                    printf("%c", *(unsigned char *)p);
            else if (strcmp(argv[1], "write") == 0)
                    *(unsigned char *)p = 0;
            else if (strcmp(argv[1], "exec") == 0)
                    ((void (*)(void))p)();
            return 1;  /* failed to generate SEGV */
    }

Fixes: c3350602e8 ("powerpc/mm: Make bad_area* helper functions")
Cc: stable@vger.kernel.org # v4.14+
Signed-off-by: John Sperbeck <jsperbeck@google.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
[mpe: Add commit references in change log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-02 21:12:33 +11:00
Andrew Lunn 39c3fd5895 kernel/irq: Extend lockdep class for request mutex
The IRQ code already has support for lockdep class for the lock mutex
in an interrupt descriptor. Extend this to add a second class for the
request mutex in the descriptor. Not having a class is resulting in
false positive splats in some code paths.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: linus.walleij@linaro.org
Cc: grygorii.strashko@ti.com
Cc: f.fainelli@gmail.com
Link: https://lkml.kernel.org/r/1512234664-21555-1-git-send-email-andrew@lunn.ch
2017-12-28 12:26:35 +01:00
Linus Torvalds caf9a82657 Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 PTI preparatory patches from Thomas Gleixner:
 "Todays Advent calendar window contains twentyfour easy to digest
  patches. The original plan was to have twenty three matching the date,
  but a late fixup made that moot.

   - Move the cpu_entry_area mapping out of the fixmap into a separate
     address space. That's necessary because the fixmap becomes too big
     with NRCPUS=8192 and this caused already subtle and hard to
     diagnose failures.

     The top most patch is fresh from today and cures a brain slip of
     that tall grumpy german greybeard, who ignored the intricacies of
     32bit wraparounds.

   - Limit the number of CPUs on 32bit to 64. That's insane big already,
     but at least it's small enough to prevent address space issues with
     the cpu_entry_area map, which have been observed and debugged with
     the fixmap code

   - A few TLB flush fixes in various places plus documentation which of
     the TLB functions should be used for what.

   - Rename the SYSENTER stack to CPU_ENTRY_AREA stack as it is used for
     more than sysenter now and keeping the name makes backtraces
     confusing.

   - Prevent LDT inheritance on exec() by moving it to arch_dup_mmap(),
     which is only invoked on fork().

   - Make vysycall more robust.

   - A few fixes and cleanups of the debug_pagetables code. Check
     PAGE_PRESENT instead of checking the PTE for 0 and a cleanup of the
     C89 initialization of the address hint array which already was out
     of sync with the index enums.

   - Move the ESPFIX init to a different place to prepare for PTI.

   - Several code moves with no functional change to make PTI
     integration simpler and header files less convoluted.

   - Documentation fixes and clarifications"

* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits)
  x86/cpu_entry_area: Prevent wraparound in setup_cpu_entry_area_ptes() on 32bit
  init: Invoke init_espfix_bsp() from mm_init()
  x86/cpu_entry_area: Move it out of the fixmap
  x86/cpu_entry_area: Move it to a separate unit
  x86/mm: Create asm/invpcid.h
  x86/mm: Put MMU to hardware ASID translation in one place
  x86/mm: Remove hard-coded ASID limit checks
  x86/mm: Move the CR3 construction functions to tlbflush.h
  x86/mm: Add comments to clarify which TLB-flush functions are supposed to flush what
  x86/mm: Remove superfluous barriers
  x86/mm: Use __flush_tlb_one() for kernel memory
  x86/microcode: Dont abuse the TLB-flush interface
  x86/uv: Use the right TLB-flush API
  x86/entry: Rename SYSENTER_stack to CPU_ENTRY_AREA_entry_stack
  x86/doc: Remove obvious weirdnesses from the x86 MM layout documentation
  x86/mm/64: Improve the memory map documentation
  x86/ldt: Prevent LDT inheritance on exec
  x86/ldt: Rework locking
  arch, mm: Allow arch_dup_mmap() to fail
  x86/vsyscall/64: Warn and fail vsyscall emulation in NATIVE mode
  ...
2017-12-23 11:53:04 -08:00
Linus Torvalds 9c294ec084 powerpc fixes for 4.15 #5
Of note is two fixes for KVM XIVE (Power9 interrupt controller). These would
 normally go via the KVM tree but Paul is away so I've picked them up.
 
 Other than that, two fixes for error handling in the IMC driver, and one for a
 potential oops in the BHRB code if the hardware records a branch address that
 has subsequently been unmapped, and finally a s/%p/%px/ in our oops code.
 
 Thanks to:
   Anju T Sudhakar, Cédric Le Goater, Laurent Vivier, Madhavan Srinivasan, Naveen
   N. Rao, Ravi Bangoria.
 -----BEGIN PGP SIGNATURE-----
 
 iQIwBAABCAAaBQJaPNx6ExxtcGVAZWxsZXJtYW4uaWQuYXUACgkQUevqPMjhpYBm
 Dw/+K2DRM23L4I1OD+i71N0F9DIxoS95FhIheqnidJxWfff+sFyRhL1IQa6AUTfv
 9vLGUQ6IcqmrzyiHClewRVsX0DeXB1mYpoCBIqhgyL1cspkp+cP7DubpaeB1wXpQ
 vlq2VL6ZfeRAGvMykLIoE/xXtfVx8CuaAjY9AUIFvRRP4vupcpbl503cHEXmhaP9
 GaV+8poslwbxYf9ZPucPJVg4dxmT2dEb/xiZ6lLTDt3QXZx3abnFWYXhxGkdGhpt
 yPszkE3cDlypsa2nPfotEby4ThE9D4Ypxk1unSQfcFkaVjKAwwQ9MDED8E1NpEH5
 hqxmYoUNqLcftcxSZHX93acyHgKfvfM69i/vN7YwjhMEISdSDYCTaDrkxv5ntK4S
 A3FncuApqYPMRtFi+8O4AinUS2t2KkdLYckP1bXC++++F9wRth3iifK4QTj6cV9u
 V4aAPWvNSTgye0lokcwQF2KVdfdku9pl/85bclKddwGa1byscvNvCVPKuexoR3fM
 /PSNgzOizTMiAkuEO4WYmmuNNziSUjIMEWTfO4jIi2jKhuxg+s6hPg7SYN+iyQ/T
 il4b/fjsX6snXtwzxH2Xjche3c0UIN8UfgEkgKO21gbdrr7Ec6IIzkdgwu2jMHnt
 fEzUPYtW0vH9OKRqgKkY+YHYsBXNXu+pFUAu2jaG3KfPSWE=
 =d5wh
 -----END PGP SIGNATURE-----

Merge tag 'powerpc-4.15-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc fixes from Michael Ellerman:
 "This is all fairly boring, except that there's two KVM fixes that
  you'd normally get via Paul's kvm-ppc tree. He's away so I picked them
  up. I was waiting to see if he would apply them, which is why they
  have only been in my tree since today. But they were on the list for a
  while and have been tested on the relevant hardware.

  Of note is two fixes for KVM XIVE (Power9 interrupt controller). These
  would normally go via the KVM tree but Paul is away so I've picked
  them up.

  Other than that, two fixes for error handling in the IMC driver, and
  one for a potential oops in the BHRB code if the hardware records a
  branch address that has subsequently been unmapped, and finally a
  s/%p/%px/ in our oops code.

  Thanks to: Anju T Sudhakar, Cédric Le Goater, Laurent Vivier, Madhavan
  Srinivasan, Naveen N. Rao, Ravi Bangoria"

* tag 'powerpc-4.15-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  KVM: PPC: Book3S HV: Fix pending_pri value in kvmppc_xive_get_icp()
  KVM: PPC: Book3S: fix XIVE migration of pending interrupts
  powerpc/kernel: Print actual address of regs when oopsing
  powerpc/perf: Fix kfree memory allocated for nest pmus
  powerpc/perf/imc: Fix nest-imc cpuhotplug callback failure
  powerpc/perf: Dereference BHRB entries safely
2017-12-22 12:38:30 -08:00
Thomas Gleixner c10e83f598 arch, mm: Allow arch_dup_mmap() to fail
In order to sanitize the LDT initialization on x86 arch_dup_mmap() must be
allowed to fail. Fix up all instances.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Andy Lutomirsky <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@linux.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: H. Peter Anvin <hpa@zytor.com>
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: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: dan.j.williams@intel.com
Cc: hughd@google.com
Cc: keescook@google.com
Cc: kirill.shutemov@linux.intel.com
Cc: linux-mm@kvack.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-12-22 20:13:01 +01:00
Laurent Vivier 7333b5aca4 KVM: PPC: Book3S HV: Fix pending_pri value in kvmppc_xive_get_icp()
When we migrate a VM from a POWER8 host (XICS) to a POWER9 host
(XICS-on-XIVE), we have an error:

qemu-kvm: Unable to restore KVM interrupt controller state \
          (0xff000000) for CPU 0: Invalid argument

This is because kvmppc_xics_set_icp() checks the new state
is internaly consistent, and especially:

...
   1129         if (xisr == 0) {
   1130                 if (pending_pri != 0xff)
   1131                         return -EINVAL;
...

On the other side, kvmppc_xive_get_icp() doesn't set
neither the pending_pri value, nor the xisr value (set to 0)
(and kvmppc_xive_set_icp() ignores the pending_pri value)

As xisr is 0, pending_pri must be set to 0xff.

Fixes: 5af5099385 ("KVM: PPC: Book3S HV: Native usage of the XIVE interrupt controller")
Cc: stable@vger.kernel.org # v4.12+
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-12-22 15:36:24 +11:00
Cédric Le Goater dc1c4165d1 KVM: PPC: Book3S: fix XIVE migration of pending interrupts
When restoring a pending interrupt, we are setting the Q bit to force
a retrigger in xive_finish_unmask(). But we also need to force an EOI
in this case to reach the same initial state : P=1, Q=0.

This can be done by not setting 'old_p' for pending interrupts which
will inform xive_finish_unmask() that an EOI needs to be sent.

Fixes: 5af5099385 ("KVM: PPC: Book3S HV: Native usage of the XIVE interrupt controller")
Cc: stable@vger.kernel.org # v4.12+
Suggested-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Tested-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-12-22 15:34:02 +11:00
Michael Ellerman 182dc9c7f2 powerpc/kernel: Print actual address of regs when oopsing
When we oops or otherwise call show_regs() we print the address of the
regs structure. Being able to see the address is fairly useful,
firstly to verify that the regs pointer is not completely bogus, and
secondly it allows you to dump the regs and surrounding memory with a
debugger if you have one.

In the normal case the regs will be located somewhere on the stack, so
printing their location discloses no further information than printing
the stack pointer does already.

So switch to %px and print the actual address, not the hashed value.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-12-19 13:09:40 +11:00
Daniel Borkmann 87338c8e2c bpf, ppc64: do not reload skb pointers in non-skb context
The assumption of unconditionally reloading skb pointers on
BPF helper calls where bpf_helper_changes_pkt_data() holds
true is wrong. There can be different contexts where the helper
would enforce a reload such as in case of XDP. Here, we do
have a struct xdp_buff instead of struct sk_buff as context,
thus this will access garbage.

JITs only ever need to deal with cached skb pointer reload
when ld_abs/ind was seen, therefore guard the reload behind
SEEN_SKB.

Fixes: 156d0e290e ("powerpc/ebpf/jit: Implement JIT compiler for extended BPF")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: Sandipan Das <sandipan@linux.vnet.ibm.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2017-12-15 09:19:35 -08:00
Anju T Sudhakar 110df8bd3e powerpc/perf: Fix kfree memory allocated for nest pmus
imc_common_cpuhp_mem_free() is the common function for all
IMC (In-memory Collection counters) domains to unregister cpuhotplug
callback and free memory. Since kfree of memory allocated for
nest-imc (per_nest_pmu_arr) is in the common code, all
domains (core/nest/thread) can do the kfree in the failure case.

This could potentially create a call trace as shown below, where
core(/thread/nest) imc pmu initialization fails and in the failure
path imc_common_cpuhp_mem_free() free the memory(per_nest_pmu_arr),
which is allocated by successfully registered nest units.

The call trace is generated in a scenario where core-imc
initialization is made to fail and a cpuhotplug is performed in a p9
system. During cpuhotplug ppc_nest_imc_cpu_offline() tries to access
per_nest_pmu_arr, which is already freed by core-imc.

  NIP [c000000000cb6a94] mutex_lock+0x34/0x90
  LR [c000000000cb6a88] mutex_lock+0x28/0x90
  Call Trace:
    mutex_lock+0x28/0x90 (unreliable)
    perf_pmu_migrate_context+0x90/0x3a0
    ppc_nest_imc_cpu_offline+0x190/0x1f0
    cpuhp_invoke_callback+0x160/0x820
    cpuhp_thread_fun+0x1bc/0x270
    smpboot_thread_fn+0x250/0x290
    kthread+0x1a8/0x1b0
    ret_from_kernel_thread+0x5c/0x74

To address this scenario do the kfree(per_nest_pmu_arr) only in case
of nest-imc initialization failure, and when there is no other nest
units registered.

Fixes: 73ce9aec65 ("powerpc/perf: Fix IMC_MAX_PMU macro")
Signed-off-by: Anju T Sudhakar <anju@linux.vnet.ibm.com>
Reviewed-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-12-13 20:51:22 +11:00
Anju T Sudhakar ad2b6e0102 powerpc/perf/imc: Fix nest-imc cpuhotplug callback failure
Oops is observed during boot:

  Faulting instruction address: 0xc000000000248340
  cpu 0x0: Vector: 380 (Data Access Out of Range) at [c000000ff66fb850]
      pc: c000000000248340: event_function_call+0x50/0x1f0
      lr: c00000000024878c: perf_remove_from_context+0x3c/0x100
      sp: c000000ff66fbad0
     msr: 9000000000009033
     dar: 7d20e2a6f92d03c0
    pid = 14, comm = cpuhp/0

While registering the cpuhotplug callbacks for nest-imc, if we fail in
the cpuhotplug online path for any random node in a multi node
system (because the opal call to stop nest-imc counters fails for that
node), ppc_nest_imc_cpu_offline() will get invoked for other nodes who
successfully returned from cpuhotplug online path.

This call trace is generated since in the ppc_nest_imc_cpu_offline()
path we are trying to migrate the event context, when nest-imc
counters are not even initialized.

Patch to add a check to ensure that nest-imc is registered before
migrating the event context.

Fixes: 885dcd709b ("powerpc/perf: Add nest IMC PMU support")
Signed-off-by: Anju T Sudhakar <anju@linux.vnet.ibm.com>
Reviewed-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-12-13 20:36:53 +11:00
Ravi Bangoria f41d84dddc powerpc/perf: Dereference BHRB entries safely
It's theoretically possible that branch instructions recorded in
BHRB (Branch History Rolling Buffer) entries have already been
unmapped before they are processed by the kernel. Hence, trying to
dereference such memory location will result in a crash. eg:

    Unable to handle kernel paging request for data at address 0xd000000019c41764
    Faulting instruction address: 0xc000000000084a14
    NIP [c000000000084a14] branch_target+0x4/0x70
    LR [c0000000000eb828] record_and_restart+0x568/0x5c0
    Call Trace:
    [c0000000000eb3b4] record_and_restart+0xf4/0x5c0 (unreliable)
    [c0000000000ec378] perf_event_interrupt+0x298/0x460
    [c000000000027964] performance_monitor_exception+0x54/0x70
    [c000000000009ba4] performance_monitor_common+0x114/0x120

Fix it by deferefencing the addresses safely.

Fixes: 691231846c ("powerpc/perf: Fix setting of "to" addresses for BHRB")
Cc: stable@vger.kernel.org # v3.10+
Suggested-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Reviewed-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
[mpe: Use probe_kernel_read() which is clearer, tweak change log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-12-13 20:29:20 +11:00
Linus Torvalds e9ef1fe312 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) CAN fixes from Martin Kelly (cancel URBs properly in all the CAN usb
    drivers).

 2) Revert returning -EEXIST from __dev_alloc_name() as this propagates
    to userspace and broke some apps. From Johannes Berg.

 3) Fix conn memory leaks and crashes in TIPC, from Jon Malloc and Cong
    Wang.

 4) Gianfar MAC can't do EEE so don't advertise it by default, from
    Claudiu Manoil.

 5) Relax strict netlink attribute validation, but emit a warning. From
    David Ahern.

 6) Fix regression in checksum offload of thunderx driver, from Florian
    Westphal.

 7) Fix UAPI bpf issues on s390, from Hendrik Brueckner.

 8) New card support in iwlwifi, from Ihab Zhaika.

 9) BBR congestion control bug fixes from Neal Cardwell.

10) Fix port stats in nfp driver, from Pieter Jansen van Vuuren.

11) Fix leaks in qualcomm rmnet, from Subash Abhinov Kasiviswanathan.

12) Fix DMA API handling in sh_eth driver, from Thomas Petazzoni.

13) Fix spurious netpoll warnings in bnxt_en, from Calvin Owens.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (67 commits)
  net: mvpp2: fix the RSS table entry offset
  tcp: evaluate packet losses upon RTT change
  tcp: fix off-by-one bug in RACK
  tcp: always evaluate losses in RACK upon undo
  tcp: correctly test congestion state in RACK
  bnxt_en: Fix sources of spurious netpoll warnings
  tcp_bbr: reset long-term bandwidth sampling on loss recovery undo
  tcp_bbr: reset full pipe detection on loss recovery undo
  tcp_bbr: record "full bw reached" decision in new full_bw_reached bit
  sfc: pass valid pointers from efx_enqueue_unwind
  gianfar: Disable EEE autoneg by default
  tcp: invalidate rate samples during SACK reneging
  can: peak/pcie_fd: fix potential bug in restarting tx queue
  can: usb_8dev: cancel urb on -EPIPE and -EPROTO
  can: kvaser_usb: cancel urb on -EPIPE and -EPROTO
  can: esd_usb2: cancel urb on -EPIPE and -EPROTO
  can: ems_usb: cancel urb on -EPIPE and -EPROTO
  can: mcba_usb: cancel urb on -EPROTO
  usbnet: fix alignment for frames with no ethernet header
  tcp: use current time in tcp_rcv_space_adjust()
  ...
2017-12-08 13:32:44 -08:00
Michael Ellerman d810418208 powerpc/xmon: Don't print hashed pointers in xmon
Since commit ad67b74d24 ("printk: hash addresses printed with %p")
pointers printed with %p are hashed, ie. you don't see the actual
pointer value but rather a cryptographic hash of its value.

In xmon we want to see the actual pointer values, because xmon is a
debugger, so replace %p with %px which prints the actual pointer
value.

We justify doing this in xmon because 1) xmon is a kernel crash
debugger, it's only accessible via the console 2) xmon doesn't print
to dmesg, so the pointers it prints are not able to be leaked that
way.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-12-07 00:27:01 +11:00
Nicholas Piggin 371b80447f powerpc/64s: Initialize ISAv3 MMU registers before setting partition table
kexec can leave MMU registers set when booting into a new kernel,
the PIDR (Process Identification Register) in particular. The boot
sequence does not zero PIDR, so it only gets set when CPUs first
switch to a userspace processes (until then it's running a kernel
thread with effective PID = 0).

This leaves a window where a process table entry and page tables are
set up due to user processes running on other CPUs, that happen to
match with a stale PID. The CPU with that PID may cause speculative
accesses that address quadrant 0 (aka userspace addresses), which will
result in cached translations and PWC (Page Walk Cache) for that
process, on a CPU which is not in the mm_cpumask and so they will not
be invalidated properly.

The most common result is the kernel hanging in infinite page fault
loops soon after kexec (usually in schedule_tail, which is usually the
first non-speculative quadrant 0 access to a new PID) due to a stale
PWC. However being a stale translation error, it could result in
anything up to security and data corruption problems.

Fix this by zeroing out PIDR at boot and kexec.

Fixes: 7e381c0ff6 ("powerpc/mm/radix: Add mmu context handling callback for radix")
Cc: stable@vger.kernel.org # v4.7+
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-12-06 23:32:43 +11:00
Serhii Popovych 4ed11aeefd KVM: PPC: Book3S HV: Fix use after free in case of multiple resize requests
When serving multiple resize requests following could happen:

    CPU0                                    CPU1
    ----                                    ----
    kvm_vm_ioctl_resize_hpt_prepare(1);
      -> schedule_work()
                                            /* system_rq might be busy: delay */
    kvm_vm_ioctl_resize_hpt_prepare(2);
      mutex_lock();
      if (resize) {
         ...
         release_hpt_resize();
      }
      ...                                   resize_hpt_prepare_work()
      -> schedule_work()                    {
      mutex_unlock()                           /* resize->kvm could be wrong */
                                               struct kvm *kvm = resize->kvm;

                                               mutex_lock(&kvm->lock);   <<<< UAF
                                               ...
                                            }

i.e. a second resize request with different order could be started by
kvm_vm_ioctl_resize_hpt_prepare(), causing the previous request to be
free()d when there's still an active worker thread which will try to
access it.  This leads to a use after free in point marked with UAF on
the diagram above.

To prevent this from happening, instead of unconditionally releasing a
pre-existing resize structure from the prepare ioctl(), we check if
the existing structure has an in-progress worker.  We do that by
checking if the resize->error == -EBUSY, which is safe because the
resize->error field is protected by the kvm->lock.  If there is an
active worker, instead of releasing, we mark the structure as stale by
unlinking it from kvm_struct.

In the worker thread we check for a stale structure (with kvm->lock
held), and in that case abort, releasing the stale structure ourself.
We make the check both before and the actual allocation.  Strictly,
only the check afterwards is needed, the check before is an
optimization: if the structure happens to become stale before the
worker thread is dispatched, rather than during the allocation, it
means we can avoid allocating then immediately freeing a potentially
substantial amount of memory.

This fixes following or similar host kernel crash message:

[  635.277361] Unable to handle kernel paging request for data at address 0x00000000
[  635.277438] Faulting instruction address: 0xc00000000052f568
[  635.277446] Oops: Kernel access of bad area, sig: 11 [#1]
[  635.277451] SMP NR_CPUS=2048 NUMA PowerNV
[  635.277470] Modules linked in: xt_CHECKSUM iptable_mangle ipt_MASQUERADE
nf_nat_masquerade_ipv4 iptable_nat nf_nat_ipv4 nf_nat nf_conntrack_ipv4
nf_defrag_ipv4 xt_conntrack nf_conntrack ipt_REJECT nf_reject_ipv4 tun bridge stp llc
ebtable_filter ebtables ip6table_filter ip6_tables iptable_filter nfsv3 nfs_acl nfs
lockd grace fscache kvm_hv kvm rpcrdma sunrpc ib_isert iscsi_target_mod ib_iser libiscsi
scsi_transport_iscsi ib_srpt target_core_mod ext4 ib_srp scsi_transport_srp
ib_ipoib mbcache jbd2 rdma_ucm ib_ucm ib_uverbs ib_umad rdma_cm ib_cm iw_cm ocrdma(T)
ib_core ses enclosure scsi_transport_sas sg shpchp leds_powernv ibmpowernv i2c_opal
i2c_core powernv_rng ipmi_powernv ipmi_devintf ipmi_msghandler ip_tables xfs
libcrc32c sr_mod sd_mod cdrom lpfc nvme_fc(T) nvme_fabrics nvme_core ipr nvmet_fc(T)
tg3 nvmet libata be2net crc_t10dif crct10dif_generic scsi_transport_fc ptp scsi_tgt
pps_core crct10dif_common dm_mirror dm_region_hash dm_log dm_mod
[  635.278687] CPU: 40 PID: 749 Comm: kworker/40:1 Tainted: G
------------ T 3.10.0.bz1510771+ #1
[  635.278782] Workqueue: events resize_hpt_prepare_work [kvm_hv]
[  635.278851] task: c0000007e6840000 ti: c0000007e9180000 task.ti: c0000007e9180000
[  635.278919] NIP: c00000000052f568 LR: c0000000009ea310 CTR: c0000000009ea4f0
[  635.278988] REGS: c0000007e91837f0 TRAP: 0300   Tainted: G
------------ T  (3.10.0.bz1510771+)
[  635.279077] MSR: 9000000100009033 <SF,HV,EE,ME,IR,DR,RI,LE>  CR: 24002022  XER:
00000000
[  635.279248] CFAR: c000000000009368 DAR: 0000000000000000 DSISR: 40000000 SOFTE: 1
GPR00: c0000000009ea310 c0000007e9183a70 c000000001250b00 c0000007e9183b10
GPR04: 0000000000000000 0000000000000000 c0000007e9183650 0000000000000000
GPR08: c0000007ffff7b80 00000000ffffffff 0000000080000028 d00000000d2529a0
GPR12: 0000000000002200 c000000007b56800 c000000000120028 c0000007f135bb40
GPR16: 0000000000000000 c000000005c1e018 c000000005c1e018 0000000000000000
GPR20: 0000000000000001 c0000000011bf778 0000000000000001 fffffffffffffef7
GPR24: 0000000000000000 c000000f1e262e50 0000000000000002 c0000007e9180000
GPR28: c000000f1e262e4c c000000f1e262e50 0000000000000000 c0000007e9183b10
[  635.280149] NIP [c00000000052f568] __list_add+0x38/0x110
[  635.280197] LR [c0000000009ea310] __mutex_lock_slowpath+0xe0/0x2c0
[  635.280253] Call Trace:
[  635.280277] [c0000007e9183af0] [c0000000009ea310] __mutex_lock_slowpath+0xe0/0x2c0
[  635.280356] [c0000007e9183b70] [c0000000009ea554] mutex_lock+0x64/0x70
[  635.280426] [c0000007e9183ba0] [d00000000d24da04]
resize_hpt_prepare_work+0xe4/0x1c0 [kvm_hv]
[  635.280507] [c0000007e9183c40] [c000000000113c0c] process_one_work+0x1dc/0x680
[  635.280587] [c0000007e9183ce0] [c000000000114250] worker_thread+0x1a0/0x520
[  635.280655] [c0000007e9183d80] [c00000000012010c] kthread+0xec/0x100
[  635.280724] [c0000007e9183e30] [c00000000000a4b8] ret_from_kernel_thread+0x5c/0xa4
[  635.280814] Instruction dump:
[  635.280880] 7c0802a6 fba1ffe8 fbc1fff0 7cbd2b78 fbe1fff8 7c9e2378 7c7f1b78
f8010010
[  635.281099] f821ff81 e8a50008 7fa52040 40de00b8 <e8be0000> 7fbd2840 40de008c
7fbff040
[  635.281324] ---[ end trace b628b73449719b9d ]---

Cc: stable@vger.kernel.org # v4.10+
Fixes: b5baa68773 ("KVM: PPC: Book3S HV: KVM-HV HPT resizing implementation")
Signed-off-by: Serhii Popovych <spopovyc@redhat.com>
[dwg: Replaced BUG_ON()s with WARN_ONs() and reworded commit message
 for clarity]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2017-12-06 13:36:22 +11:00
Serhii Popovych 3073774e63 KVM: PPC: Book3S HV: Drop prepare_done from struct kvm_resize_hpt
Currently the kvm_resize_hpt structure has two fields relevant to the
state of an ongoing resize: 'prepare_done', which indicates whether
the worker thread has completed or not, and 'error' which indicates
whether it was successful or not.

Since the success/failure isn't known until completion, this is
confusingly redundant.  This patch consolidates the information into
just the 'error' value: -EBUSY indicates the worked is still in
progress, other negative values indicate (completed) failure, 0
indicates successful completion.

As a bonus this reduces size of struct kvm_resize_hpt by
__alignof__(struct kvm_hpt_info) and saves few bytes of code.

While there correct comment in struct kvm_resize_hpt which references
a non-existent semaphore (leftover from an early draft).

Assert with WARN_ON() in case of HPT allocation thread work runs more
than once for resize request or resize_hpt_allocate() returns -EBUSY
that is treated specially.

Change comparison against zero to make checkpatch.pl happy.

Cc: stable@vger.kernel.org # v4.10+
Signed-off-by: Serhii Popovych <spopovyc@redhat.com>
[dwg: Changed BUG_ON()s to WARN_ON()s and altered commit message for
 clarity]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2017-12-06 13:35:21 +11:00
Hendrik Brueckner c895f6f703 bpf: correct broken uapi for BPF_PROG_TYPE_PERF_EVENT program type
Commit 0515e5999a ("bpf: introduce BPF_PROG_TYPE_PERF_EVENT
program type") introduced the bpf_perf_event_data structure which
exports the pt_regs structure.  This is OK for multiple architectures
but fail for s390 and arm64 which do not export pt_regs.  Programs
using them, for example, the bpf selftest fail to compile on these
architectures.

For s390, exporting the pt_regs is not an option because s390 wants
to allow changes to it.  For arm64, there is a user_pt_regs structure
that covers parts of the pt_regs structure for use by user space.

To solve the broken uapi for s390 and arm64, introduce an abstract
type for pt_regs and add an asm/bpf_perf_event.h file that concretes
the type.  An asm-generic header file covers the architectures that
export pt_regs today.

The arch-specific enablement for s390 and arm64 follows in separate
commits.

Reported-by: Thomas Richter <tmricht@linux.vnet.ibm.com>
Fixes: 0515e5999a ("bpf: introduce BPF_PROG_TYPE_PERF_EVENT program type")
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Reviewed-and-tested-by: Thomas Richter <tmricht@linux.vnet.ibm.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-05 15:02:40 +01:00
David Gibson ab9dbf771f Revert "powerpc: Do not call ppc_md.panic in fadump panic notifier"
This reverts commit a3b2cb30f2.

That commit tried to fix problems with panic on powerpc in certain
circumstances, where some output from the generic panic code was being
dropped.

Unfortunately, it breaks things worse in other circumstances. In
particular when running a PAPR guest, it will now attempt to reboot
instead of informing the hypervisor (KVM or PowerVM) that the guest
has crashed. The crash notification is important to some
virtualization management layers.

Revert it for now until we can come up with a better solution.

Fixes: a3b2cb30f2 ("powerpc: Do not call ppc_md.panic in fadump panic notifier")
Cc: stable@vger.kernel.org # v4.14+
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
[mpe: Tweak change log a bit]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-12-05 23:21:46 +11:00
Ravi Bangoria 5aa04b3eb6 powerpc/perf: Fix oops when grouping different pmu events
When user tries to group imc (In-Memory Collections) event with
normal event, (sometime) kernel crashes with following log:

    Faulting instruction address: 0x00000000
    [link register   ] c00000000010ce88 power_check_constraints+0x128/0x980
    ...
    c00000000010e238 power_pmu_event_init+0x268/0x6f0
    c0000000002dc60c perf_try_init_event+0xdc/0x1a0
    c0000000002dce88 perf_event_alloc+0x7b8/0xac0
    c0000000002e92e0 SyS_perf_event_open+0x530/0xda0
    c00000000000b004 system_call+0x38/0xe0

'event_base' field of 'struct hw_perf_event' is used as flags for
normal hw events and used as memory address for imc events. While
grouping these two types of events, collect_events() tries to
interpret imc 'event_base' as a flag, which causes a corruption
resulting in a crash.

Consider only those events which belongs to 'perf_hw_context' in
collect_events().

Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Reviewed-By: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-12-04 16:03:19 +11:00