Commit Graph

14461 Commits

Author SHA1 Message Date
Aneesh Kumar K.V
26b6a3d9bb powerpc/mm: move pte headers to book3s directory
Acked-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-12-14 15:19:04 +11:00
Aneesh Kumar K.V
0863d7f213 powerpc/mm: Fix infinite loop in hash fault with 4K page size
This is the same bug we fixed as part of 09567e7fd4
("powerpc/mm: Check paca psize is up to date for huge mappings"). Please
check that for details. The difference here is that faults were
happening on a 4K page at an address previously mapped by hugetlb.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Reviewed-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-12-14 15:19:04 +11:00
Scott Wood
666db563d3 EDAC, mpc85xx: Make mpc85xx-pci-edac a platform device
Originally the mpc85xx-pci-edac driver bound directly to the PCI
controller node.

Commit

  905e75c46d ("powerpc/fsl-pci: Unify pci/pcie initialization code")

turned the PCI controller code into a platform device. Since we can't
have two drivers binding to the same device, the EDAC code was changed
to be called into as a library-style submodule. However, this doesn't
work if the EDAC driver is built as a module.

Commit

  8d8fcba6d1ea ("EDAC: Rip out the edac_subsys reference counting")

exposed another problem with this approach -- mpc85xx_pci_err_probe()
was being called in the same early boot phase that the PCI controller
is initialized, rather than in the device_initcall phase that the EDAC
layer expects. This caused a crash on boot.

To fix this, the PCI controller code now creates a child platform device
specifically for EDAC, which the mpc85xx-pci-edac driver binds to.

Reported-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Scott Wood <scottwood@freescale.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Daniel Axtens <dja@axtens.net>
Cc: Doug Thompson <dougthompson@xmission.com>
Cc: Jia Hongtao <B38951@freescale.com>
Cc: Jiri Kosina <jkosina@suse.com>
Cc: Kim Phillips <kim.phillips@freescale.com>
Cc: linux-edac <linux-edac@vger.kernel.org>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: Masanari Iida <standby24x7@gmail.com>
Cc: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Rob Herring <robh@kernel.org>
Link: http://lkml.kernel.org/r/1449774432-18593-1-git-send-email-scottwood@freescale.com
Signed-off-by: Borislav Petkov <bp@suse.de>
2015-12-11 16:56:16 +01:00
Bjorn Helgaas
800e07b609 Merge branches 'pci/aspm', 'pci/hotplug', 'pci/misc' and 'pci/msi' into next
* pci/aspm:
  PCI/ASPM: Make sysfs link_state_store() consistent with link_state_show()

* pci/hotplug:
  PCI: pciehp: Always protect pciehp_disable_slot() with hotplug mutex

* pci/misc:
  x86/PCI: Simplify pci_bios_{read,write}
  PCI: Simplify config space size computation
  PCI: Limit config space size for Netronome NFP6000 family
  PCI: Add Netronome vendor and device IDs
  PCI: Support PCIe devices with short cfg_size
  x86/PCI: Clarify AMD Fam10h config access restrictions comment
  PCI: Print warnings for all invalid expansion ROM headers
  PCI: Check for PCI_HEADER_TYPE_BRIDGE equality, not bitmask

* pci/msi:
  PCI/MSI: Remove empty pci_msi_init_pci_dev()
  PCI/MSI: Initialize MSI capability for all architectures
2015-12-10 19:40:14 -06:00
Bjorn Helgaas
93de690176 PCI: Check for PCI_HEADER_TYPE_BRIDGE equality, not bitmask
Bit 7 of the "Header Type" register indicates a multi-function device when
set.  Bits 0-6 contain encoded values, where 0x1 indicates a PCI-PCI
bridge.  It is incorrect to test this as though it were a mask.

For example, while the PCI 3.0 spec only defines values 0x0, 0x1, and 0x2,
it's conceivable that a future spec could define 0x3 to mean something
else; then tests for "(hdr_type & 0x7f) & PCI_HEADER_TYPE_BRIDGE" would
incorrectly succeed for this new 0x3 header type.

Test bits 0-6 of the Header Type for equality with PCI_HEADER_TYPE_BRIDGE.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2015-12-10 19:38:06 -06:00
Anton Blanchard
db1231dcdb powerpc: Fix DSCR inheritance over fork()
Two DSCR tests have a hack in them:

	/*
	 * XXX: Force a context switch out so that DSCR
	 * current value is copied into the thread struct
	 * which is required for the child to inherit the
	 * changed value.
	 */
	sleep(1);

We should not be working around this in the testcase, it is a kernel bug.
Fix it by copying the current DSCR to the child, instead of what we
had in the thread struct at last context switch.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-12-10 21:11:13 +11:00
Anton Blanchard
20dbe67062 powerpc: Call restore_sprs() before _switch()
commit 152d523e63 ("powerpc: Create context switch helpers save_sprs()
and restore_sprs()") moved the restore of SPRs after the call to _switch().

There is an issue with this approach - new tasks do not return through
_switch(), they are set up by copy_thread() to directly return through
ret_from_fork() or ret_from_kernel_thread(). This means restore_sprs() is
not getting called for new tasks.

Fix this by moving restore_sprs() before _switch().

Fixes: 152d523e63 ("powerpc: Create context switch helpers save_sprs() and restore_sprs()")
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-12-10 21:10:55 +11:00
Anton Blanchard
d64d02ce4e powerpc: Call check_if_tm_restore_required() in enable_kernel_*()
Commit a0e72cf12b ("powerpc: Create msr_check_and_{set,clear}()")
removed a call to check_if_tm_restore_required() in the
enable_kernel_*() functions. Add them back in.

Fixes: a0e72cf12b ("powerpc: Create msr_check_and_{set,clear}()")
Reported-by: Rashmica Gupta <rashmicy@gmail.com>
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-12-10 20:10:53 +11:00
Thomas Huth
696066f875 KVM: PPC: Increase memslots to 512
Only using 32 memslots for KVM on powerpc is way too low, you can
nowadays hit this limit quite fast by adding a couple of PCI devices
and/or pluggable memory DIMMs to the guest.

x86 already increased the KVM_USER_MEM_SLOTS to 509, to satisfy 256
pluggable DIMM slots, 3 private slots and 253 slots for other things
like PCI devices (i.e. resulting in 256 + 3 + 253 = 512 slots in
total). We should do something similar for powerpc, and since we do
not use private slots here, we can set the value to 512 directly.

While we're at it, also remove the KVM_MEM_SLOTS_NUM definition
from the powerpc-specific header since this gets defined in the
generic kvm_host.h header anyway.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2015-12-10 11:36:24 +11:00
Paul Mackerras
c20875a3e6 KVM: PPC: Book3S HV: Prohibit setting illegal transaction state in MSR
Currently it is possible for userspace (e.g. QEMU) to set a value
for the MSR for a guest VCPU which has both of the TS bits set,
which is an illegal combination.  The result of this is that when
we execute a hrfid (hypervisor return from interrupt doubleword)
instruction to enter the guest, the CPU will take a TM Bad Thing
type of program interrupt (vector 0x700).

Now, if PR KVM is configured in the kernel along with HV KVM, we
actually handle this without crashing the host or giving hypervisor
privilege to the guest; instead what happens is that we deliver a
program interrupt to the guest, with SRR0 reflecting the address
of the hrfid instruction and SRR1 containing the MSR value at that
point.  If PR KVM is not configured in the kernel, then we try to
run the host's program interrupt handler with the MMU set to the
guest context, which almost certainly causes a host crash.

This closes the hole by making kvmppc_set_msr_hv() check for the
illegal combination and force the TS field to a safe value (00,
meaning non-transactional).

Cc: stable@vger.kernel.org # v3.9+
Signed-off-by: Paul Mackerras <paulus@samba.org>
2015-12-10 11:34:27 +11:00
Al Viro
b808b1d632 don't open-code generic_file_llseek_size()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-12-09 13:00:45 -05:00
Geyslan G. Bem
edfaff269f KVM: PPC: Book3S PR: Remove unused variable 'vcpu_book3s'
The vcpu_book3s variable is assigned but never used. So remove it.
Found using cppcheck.

Signed-off-by: Geyslan G. Bem <geyslan@gmail.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2015-12-09 16:06:32 +11:00
Thomas Huth
760a7364f2 KVM: PPC: Fix emulation of H_SET_DABR/X on POWER8
In the old DABR register, the BT (Breakpoint Translation) bit
is bit number 61. In the new DAWRX register, the WT (Watchpoint
Translation) bit is bit number 59. So to move the DABR-BT bit
into the position of the DAWRX-WT bit, it has to be shifted by
two, not only by one. This fixes hardware watchpoints in gdb of
older guests that only use the H_SET_DABR/X interface instead
of the new H_SET_MODE interface.

Cc: stable@vger.kernel.org # v3.14+
Signed-off-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2015-12-09 16:05:01 +11:00
Paul Mackerras
1c9e3d51d5 KVM: PPC: Book3S HV: Handle unexpected traps in guest entry/exit code better
As we saw with the TM Bad Thing type of program interrupt occurring
on the hrfid that enters the guest, it is not completely impossible
to have a trap occurring in the guest entry/exit code, despite the
fact that the code has been written to avoid taking any traps.

This adds a check in the kvmppc_handle_exit_hv() function to detect
the case when a trap has occurred in the hypervisor-mode code, and
instead of treating it just like a trap in guest code, we now print
a message and return to userspace with a KVM_EXIT_INTERNAL_ERROR
exit reason.

Of the various interrupts that get handled in the assembly code in
the guest exit path and that can return directly to the guest, the
only one that can occur when MSR.HV=1 and MSR.EE=0 is machine check
(other than system call, which we can avoid just by not doing a sc
instruction).  Therefore this adds code to the machine check path to
ensure that if the MCE occurred in hypervisor mode, we exit to the
host rather than trying to continue the guest.

Signed-off-by: Paul Mackerras <paulus@samba.org>
2015-12-09 15:46:14 +11:00
Andrew Donnellan
dc9c41bd9e Revert "powerpc/eeh: Don't unfreeze PHB PE after reset"
This reverts commit 527d10ef3a.

The reverted commit breaks cxlflash devices following an EEH reset (and
possibly other cxl devices, however this has not been tested).

The reverted commit changed the behaviour of eeh_reset_device() so that PHB
PEs are not unfrozen following the completion of the reset. This should not
be problematic, as no device resources should have been associated with the
PHB PE.

However, when attempting to load the cxlflash driver after a reset, the
driver attempts to read Vital Product Data through a call to
pci_read_vpd() (which is called on the physical cxl device, not on the
virtual AFU device). pci_read_vpd() in turn attempts to read from the cxl
device's config space. This fails, as the PE it's trying to read from is
still frozen. In turn, the driver gets an -ENODEV and fails to initialise.

It appears this issue only affects some parts of the VPD area, as "lspci
-vvv", which only reads a subset of the VPD bytes, is not broken by the
original patch.

At this stage, we don't fully understand why we're trying to read a frozen
PE, and we don't know how this affects other cxl devices. It is possible
that there is an underlying bug in the cxl driver or the powerpc CAPI
support code, or alternatively a bug in the PCI resource allocation/mapping
code that is incorrectly mapping resources to PE#0.

As such, this fix is incomplete, however it is necessary to prevent a
serious regression in CAPI support.

In the meantime, revert the commit, especially as it was intended to be a
non-functional change.

Cc: Gavin Shan <gwshan@linux.vnet.ibm.com>
Cc: Ian Munsie <imunsie@au1.ibm.com>
Cc: Daniel Axtens <dja@axtens.net>
Signed-off-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-12-09 14:05:10 +11:00
Paul Gortmaker
5b01310cfc powerpc/sbc8641: drop bogus PHY IRQ entries from DTS file
This file was originally cloned off of the MPC8641D-HPCN reference
platform, which actually had a PHY IRQ line connected. However this
board does not. The bogus entry was largely inert and went undetected
until commit 321beec504 ("net: phy: Use
interrupts when available in NOLINK state") was added to the tree.

With the above commit, the board fails to NFS boot since it sits waiting
for a PHY IRQ event that of course never arrives. Removing the bogus
entries from the DTS file fixes the issue.

Cc: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-12-09 14:00:39 +11:00
Alistair Popple
25642e1459 powerpc/opal-irqchip: Fix double endian conversion
The OPAL event calls return a mask of events that are active in big
endian format. This is checked when unmasking the events in the
irqchip by comparison with a cached value. The cached value was stored
in big endian format but should've been converted to CPU endian
first.

This bug leads to OPAL event delivery being delayed or dropped on some
systems. Symptoms may include a non-functional console.

The bug is fixed by calling opal_handle_events(...) instead of
duplicating code in opal_event_unmask(...).

Fixes: 9f0fd0499d ("powerpc/powernv: Add a virtual irqchip for opal events")
Cc: stable@vger.kernel.org # v4.2+
Reported-by: Douglas L Lehr <dllehr@us.ibm.com>
Signed-off-by: Alistair Popple <alistair@popple.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-12-08 16:53:31 +11:00
Rusty Russell
7523e4dc50 module: use a structure to encapsulate layout.
Makes it easier to handle init vs core cleanly, though the change is
fairly invasive across random architectures.

It simplifies the rbtree code immediately, however, while keeping the
core data together in the same cachline (now iff the rbtree code is
enabled).

Acked-by: Peter Zijlstra <peterz@infradead.org>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2015-12-04 22:46:25 +01:00
Davidlohr Bueso
d5a73cadf3 lcoking/barriers, arch: Use smp barriers in smp_store_release()
With commit b92b8b35a2 ("locking/arch: Rename set_mb() to smp_store_mb()")
it was made clear that the context of this call (and thus set_mb)
is strictly for CPU ordering, as opposed to IO. As such all archs
should use the smp variant of mb(), respecting the semantics and
saving a mandatory barrier on UP.

Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: <linux-arch@vger.kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: dave@stgolabs.net
Link: http://lkml.kernel.org/r/1445975631-17047-3-git-send-email-dave@stgolabs.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-12-04 11:39:51 +01:00
Anton Blanchard
d1e1cf2e38 powerpc: clean up asm/switch_to.h
Remove a bunch of unnecessary fallback functions and group
things in a more logical way.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-12-02 19:34:41 +11:00
Anton Blanchard
f3d885ccba powerpc: Rearrange __switch_to()
Most of __switch_to() is housekeeping, TLB batching, timekeeping etc.
Move these away from the more complex and critical context switching
code.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-12-02 19:34:41 +11:00
Anton Blanchard
579e633e76 powerpc: create flush_all_to_thread()
Create a single function that flushes everything (FP, VMX, VSX, SPE).
Doing this all at once means we only do one MSR write.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-12-02 19:34:40 +11:00
Anton Blanchard
c208505900 powerpc: create giveup_all()
Create a single function that gives everything up (FP, VMX, VSX, SPE).
Doing this all at once means we only do one MSR write.

A context switch microbenchmark using yield():

http://ozlabs.org/~anton/junkcode/context_switch2.c

./context_switch2 --test=yield --fp --altivec --vector 0 0

shows an improvement of 3% on POWER8.

Signed-off-by: Anton Blanchard <anton@samba.org>
[mpe: giveup_all() needs to be EXPORT_SYMBOL'ed]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-12-02 19:34:26 +11:00
Anton Blanchard
1f2e25b2d5 powerpc: Remove fp_enable() and vec_enable(), use msr_check_and_{set, clear}()
More consolidation of our MSR available bit handling.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-12-01 13:52:26 +11:00
Anton Blanchard
3eb5d5888d powerpc: Add ppc_strict_facility_enable boot option
Add a boot option that strictly manages the MSR unavailable bits.
This catches kernel uses of FP/Altivec/SPE that would otherwise
corrupt user state.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-12-01 13:52:26 +11:00
Anton Blanchard
dc4fbba11e powerpc: Create disable_kernel_{fp,altivec,vsx,spe}()
The enable_kernel_*() functions leave the relevant MSR bits enabled
until we exit the kernel sometime later. Create disable versions
that wrap the kernel use of FP, Altivec VSX or SPE.

While we don't want to disable it normally for performance reasons
(MSR writes are slow), it will be used for a debug boot option that
does this and catches bad uses in other areas of the kernel.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-12-01 13:52:25 +11:00
Anton Blanchard
a0e72cf12b powerpc: Create msr_check_and_{set,clear}()
Create helper functions to set and clear MSR bits after first
checking if they are already set. Grouping them will make it
easy to avoid the MSR writes in a subsequent optimisation.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-12-01 13:52:25 +11:00
Anton Blanchard
a7d623d4d0 powerpc: Move part of giveup_vsx into c
Move the MSR modification into c. Removing it from the assembly
function will allow us to avoid costly MSR writes by batching them
up.

Check the FP and VMX bits before calling the relevant giveup_*()
function. This makes giveup_vsx() and flush_vsx_to_thread() perform
more like their sister functions, and allows us to use
flush_vsx_to_thread() in the signal code.

Move the check_if_tm_restore_required() check in.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-12-01 13:52:25 +11:00
Anton Blanchard
98da581e08 powerpc: Move part of giveup_fpu,altivec,spe into c
Move the MSR modification into new c functions. Removing it from
the low level functions will allow us to avoid costly MSR writes
by batching them up.

Move the check_if_tm_restore_required() check into these new functions.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-12-01 13:52:25 +11:00
Anton Blanchard
b51b1153d0 powerpc: Remove NULL task struct pointer checks in FP and vector code
We used to allow giveup_*() to be called with a NULL task struct
pointer. Now those cases are handled in the caller we can remove
the checks. We can also remove giveup_altivec_notask() which is also
unused.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-12-01 13:52:25 +11:00
Anton Blanchard
611b0e5c19 powerpc: Create mtmsrd_isync()
mtmsrd_isync() will do an mtmsrd followed by an isync on older
processors. On newer processors we avoid the isync via a feature fixup.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-12-01 13:52:25 +11:00
Anton Blanchard
b86fd2bd03 powerpc: Simplify TM restore checks
Instead of having multiple giveup_*_maybe_transactional() functions,
separate out the TM check into a new function called
check_if_tm_restore_required().

This will make it easier to optimise the giveup_*() functions in a
subsequent patch.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-12-01 13:52:24 +11:00
Anton Blanchard
af1bbc3dd3 powerpc: Remove UP only lazy floating point and vector optimisations
The UP only lazy floating point and vector optimisations were written
back when SMP was not common, and neither glibc nor gcc used vector
instructions. Now SMP is very common, glibc aggressively uses vector
instructions and gcc autovectorises.

We want to add new optimisations that apply to both UP and SMP, but
in preparation for that remove these UP only optimisations.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-12-01 13:52:24 +11:00
Anton Blanchard
68bfa962bf powerpc: Remove redundant mflr in _switch
No need to execute mflr twice.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-12-01 13:52:24 +11:00
Anton Blanchard
152d523e63 powerpc: Create context switch helpers save_sprs() and restore_sprs()
Move all our context switch SPR save and restore code into two
helpers. We do a few optimisations:

- Group all mfsprs and all mtsprs. In many cases an mtspr sets a
scoreboarding bit that an mfspr waits on, so the current practise of
mfspr A; mtspr A; mfpsr B; mtspr B is the worst scheduling we can
do.

- SPR writes are slow, so check that the value is changing before
writing it.

A context switch microbenchmark using yield():

http://ozlabs.org/~anton/junkcode/context_switch2.c

./context_switch2 --test=yield 0 0

shows an improvement of almost 10% on POWER8.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-12-01 13:52:24 +11:00
Anton Blanchard
af72ab646a powerpc: Don't disable MSR bits in do_load_up_transact_*() functions
Similar to the non TM load_up_*() functions, don't disable the MSR
bits on the way out.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-12-01 13:52:24 +11:00
Anton Blanchard
07e45c120c powerpc: Don't disable kernel FP/VMX/VSX MSR bits on context switch
Writing the MSR is slow, so we want to avoid it whenever possible.

A subsequent patch will add a debug option that strictly manages the
FP/VMX/VSX unavailable bits. For now just remove it, matching what
we do in other areas of the kernel (eg enable_kernel_altivec()).

A context switch microbenchmark using yield():

http://ozlabs.org/~anton/junkcode/context_switch2.c

./context_switch2 --test=yield --fp 0 0

shows an improvement of almost 3% on POWER8.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-12-01 13:52:24 +11:00
Paul Mackerras
31a40e2b05 powerpc/64: Include KVM guest test in all interrupt vectors
Currently, if HV KVM is configured but PR KVM isn't, we don't include
a test to see whether we were interrupted in KVM guest context for the
set of interrupts which get delivered directly to the guest by hardware
if they occur in the guest.  This includes things like program
interrupts.

However, the recent bug where userspace could set the MSR for a VCPU
to have an illegal value in the TS field, and thus cause a TM Bad Thing
type of program interrupt on the hrfid that enters the guest, showed that
we can never be completely sure that these interrupts can never occur
in the guest entry/exit code.  If one of these interrupts does happen
and we have HV KVM configured but not PR KVM, then we end up trying to
run the handler in the host with the MMU set to the guest MMU context,
which generally ends badly.

Thus, for robustness it is better to have the test in every interrupt
vector, so that if some way is found to trigger some interrupt in the
guest entry/exit path, we can handle it without immediately crashing
the host.

This means that the distinction between KVMTEST and KVMTEST_PR goes
away.  Thus we delete KVMTEST_PR and associated macros and use KVMTEST
everywhere that we previously used either KVMTEST_PR or KVMTEST.  It
also means that SOFTEN_TEST_HV_201 becomes the same as SOFTEN_TEST_PR,
so we deleted SOFTEN_TEST_HV_201 and use SOFTEN_TEST_PR instead.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-12-01 13:52:23 +11:00
David Hildenbrand
e09fefdeeb KVM: Use common function for VCPU lookup by id
Let's reuse the new common function for VPCU lookup by id.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
[split out the new function into a separate patch]
2015-11-30 12:47:04 +01:00
Luis de Bethencourt
b4f8144559 powerpc/axonram: Fix module autoload for OF platform driver
This platform driver has a OF device ID table but the OF module
alias information is not created so module autoloading won't work.

Signed-off-by: Luis de Bethencourt <luisbg@osg.samsung.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-11-26 22:11:18 +11:00
Rashmica Gupta
343c3327c1 powerpc: Add rN aliases to the pt_regs_offset table.
It is common practice with powerpc to use 'rN' to refer to register 'N'. However
when using the pt_regs_offset table we have to use 'gprN'.

So add aliases such that both 'rN' and 'gprN' can be used.

For example, we can currently do:
  $ su -
  $ cd /sys/kernel/debug/tracing
  $ echo "p:probe/sys_fchownat sys_fchownat %gpr3:s32 +0(%gpr4):string %gpr5:s32 %gpr6:s32 %gpr7:s32" > kprobe_events
  $ echo 1 > events/probe/sys_fchownat/enable
  $ touch /tmp/foo
  $ chown root /tmp/foo
  $ echo 0 > events/enable
  $ cat trace
    chown-2925  [014] d...    76.160657: sys_fchownat: (SyS_fchownat+0x8/0x1a0) arg1=-100 arg2="/tmp/foo" arg3=0 arg4=-1 arg5=0

Instead we'd like to be able to use:
 $ echo "p:probe/sys_fchownat sys_fchownat %r3:s32 +0(%r4):string %r5:s32 %r6:s32 %r7:s32" > kprobe_events

Signed-off-by: Rashmica Gupta <rashmicy@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-11-26 22:11:17 +11:00
Rashmica Gupta
f43194e458 powerpc: Standardise on NR_syscalls rather than __NR_syscalls.
Most architectures use NR_syscalls as the #define for the number of syscalls.

We use __NR_syscalls, and then define NR_syscalls as __NR_syscalls.

__NR_syscalls is not used outside arch code, whereas NR_syscalls is. So as
NR_syscalls must be defined and __NR_syscalls does not, replace __NR_syscalls
with NR_syscalls.

Signed-off-by: Rashmica Gupta <rashmicy@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-11-26 22:11:17 +11:00
Rashmica Gupta
cdfc8ed690 powerpc: Remove unused function trace_syscall()
This function has been unused since commit 14cf11af6c ("powerpc: Merge enough
to start building in arch/powerpc."), so remove it.

Signed-off-by: Rashmica Gupta <rashmicy@gmail.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Reviewed-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-11-26 22:11:16 +11:00
Laurent Vivier
58531b0c80 powerpc/boot: allow wrapper to work on non-english system
if the language is not english objdump output is not parsed correctly
and format is "". Later, "ld -m $format" fails.

This patch adds "LANG=C" to force english output for objdump.

Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-11-26 22:11:16 +11:00
John Ogness
57f889471c powerpc/powermac: set IRQF_NO_THREAD for xmon/cascade handlers
The xmon and cascade irq handlers must not run as threads.
pmac_pic_lock is already a raw_spinlock, but the irq flag
IRQF_NO_THREAD needs to be set as well.

Signed-off-by: John Ogness <john.ogness@linutronix.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-11-26 22:11:05 +11:00
Yaowei Bai
378b417d65 KVM: powerpc: kvmppc_visible_gpa can be boolean
In another patch kvm_is_visible_gfn is maken return bool due to this
function only returns zero or one as its return value, let's also make
kvmppc_visible_gpa return bool to keep consistent.

No functional change.

Signed-off-by: Yaowei Bai <baiyaowei@cmss.chinamobile.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25 17:24:24 +01:00
Guilherme G. Piccoli
e80e7edc55 PCI/MSI: Initialize MSI capability for all architectures
1851617cd2 ("PCI/MSI: Disable MSI at enumeration even if kernel doesn't
support MSI") moved dev->msi_cap and dev->msix_cap initialization from the
pci_init_capabilities() path (used on all architectures) to the
pci_setup_device() path (not used on Open Firmware architectures).

This broke MSI or MSI-X on Open Firmware machines.  4d9aac397a
("powerpc/PCI: Disable MSI/MSI-X interrupts at PCI probe time in OF case")
fixed it for PowerPC but not for SPARC.

Set up MSI and MSI-X (initialize msi_cap and msix_cap and disable MSI and
MSI-X) in pci_init_capabilities() so all architectures do it the same way.

This reverts 4d9aac397a since this patch fixes the problem generically
for both PowerPC and SPARC.

[bhelgaas: changelog, make pci_msi_setup_pci_dev() static]
Fixes: 1851617cd2 ("PCI/MSI: Disable MSI at enumeration even if kernel doesn't support MSI")
Signed-off-by: Guilherme G. Piccoli <gpiccoli@linux.vnet.ibm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2015-11-24 17:45:18 -06:00
Krzysztof Kozlowski
87630eb1d5 powerpc/powernv: Drop owner assignment from platform_driver
platform_driver does not need to set an owner because
platform_driver_register() will set it.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-11-24 14:21:28 +11:00
Michael Neuling
7f821fc9c7 powerpc/tm: Check for already reclaimed tasks
Currently we can hit a scenario where we'll tm_reclaim() twice.  This
results in a TM bad thing exception because the second reclaim occurs
when not in suspend mode.

The scenario in which this can happen is the following.  We attempt to
deliver a signal to userspace.  To do this we need obtain the stack
pointer to write the signal context.  To get this stack pointer we
must tm_reclaim() in case we need to use the checkpointed stack
pointer (see get_tm_stackpointer()).  Normally we'd then return
directly to userspace to deliver the signal without going through
__switch_to().

Unfortunatley, if at this point we get an error (such as a bad
userspace stack pointer), we need to exit the process.  The exit will
result in a __switch_to().  __switch_to() will attempt to save the
process state which results in another tm_reclaim().  This
tm_reclaim() now causes a TM Bad Thing exception as this state has
already been saved and the processor is no longer in TM suspend mode.
Whee!

This patch checks the state of the MSR to ensure we are TM suspended
before we attempt the tm_reclaim().  If we've already saved the state
away, we should no longer be in TM suspend mode.  This has the
additional advantage of checking for a potential TM Bad Thing
exception.

Found using syscall fuzzer.

Fixes: fb09692e71 ("powerpc: Add reclaim and recheckpoint functions for context switching transactional memory processes")
Cc: stable@vger.kernel.org # v3.9+
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-11-23 20:18:03 +11:00
Michael Neuling
d2b9d2a5ad powerpc/tm: Block signal return setting invalid MSR state
Currently we allow both the MSR T and S bits to be set by userspace on
a signal return.  Unfortunately this is a reserved configuration and
will cause a TM Bad Thing exception if attempted (via rfid).

This patch checks for this case in both the 32 and 64 bit signals
code.  If both T and S are set, we mark the context as invalid.

Found using a syscall fuzzer.

Fixes: 2b0a576d15 ("powerpc: Add new transactional memory state to the signal context")
Cc: stable@vger.kernel.org # v3.9+
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-11-23 20:06:31 +11:00