This patch introduces new halt polling functionality into the kvm_hv kernel
module. When a vcore is idle it will poll for some period of time before
scheduling itself out.
When all of the runnable vcpus on a vcore have ceded (and thus the vcore is
idle) we schedule ourselves out to allow something else to run. In the
event that we need to wake up very quickly (for example an interrupt
arrives), we are required to wait until we get scheduled again.
Implement halt polling so that when a vcore is idle, and before scheduling
ourselves, we poll for vcpus in the runnable_threads list which have
pending exceptions or which leave the ceded state. If we poll successfully
then we can get back into the guest very quickly without ever scheduling
ourselves, otherwise we schedule ourselves out as before.
There exists generic halt_polling code in virt/kvm_main.c, however on
powerpc the polling conditions are different to the generic case. It would
be nice if we could just implement an arch specific kvm_check_block()
function, but there is still other arch specific things which need to be
done for kvm_hv (for example manipulating vcore states) which means that a
separate implementation is the best option.
Testing of this patch with a TCP round robin test between two guests with
virtio network interfaces has found a decrease in round trip time of ~15us
on average. A performance gain is only seen when going out of and
back into the guest often and quickly, otherwise there is no net benefit
from the polling. The polling interval is adjusted such that when we are
often scheduled out for long periods of time it is reduced, and when we
often poll successfully it is increased. The rate at which the polling
interval increases or decreases, and the maximum polling interval, can
be set through module parameters.
Based on the implementation in the generic kvm module by Wanpeng Li and
Paolo Bonzini, and on direction from Paul Mackerras.
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
The struct kvmppc_vcore is a structure used to store various information
about a virtual core for a kvm guest. The runnable_threads element of the
struct provides a list of all of the currently runnable vcpus on the core
(those in the KVMPPC_VCPU_RUNNABLE state). The previous implementation of
this list was a linked_list. The next patch requires that the list be able
to be iterated over without holding the vcore lock.
Reimplement the runnable_threads list in the kvmppc_vcore struct as an
array. Implement function to iterate over valid entries in the array and
update access sites accordingly.
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
The next commit will introduce a member to the kvmppc_vcore struct which
references MAX_SMT_THREADS which is defined in kvm_book3s_asm.h, however
this file isn't included in kvm_host.h directly. Thus compiling for
certain platforms such as pmac32_defconfig and ppc64e_defconfig with KVM
fails due to MAX_SMT_THREADS not being defined.
Move the struct kvmppc_vcore definition to kvm_book3s.h which explicitly
includes kvm_book3s_asm.h.
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Instead of having each caller of check_object_size() need to remember to
check for a const size parameter, move the check into check_object_size()
itself. This actually matches the original implementation in PaX, though
this commit cleans up the now-redundant builtin_const() calls in the
various architectures.
Signed-off-by: Kees Cook <keescook@chromium.org>
The compound PE is created to accommodate the devices attached to
one specific PCI bus that consume multiple M64 segments. The compound
PE is made up of one master PE and possibly multiple slave PEs. The
slave PEs should be destroyed when releasing the master PE. A kernel
crash happens when derferencing @pe->pdev on releasing the slave PE
in pnv_ioda_deconfigure_pe().
# echo 0 > /sys/bus/pci/slots/C7/power
iommu: Removing device 0000:01:00.1 from group 0
iommu: Removing device 0000:01:00.0 from group 0
Unable to handle kernel paging request for data at address 0x00000010
Faulting instruction address: 0xc00000000005d898
cpu 0x1: Vector: 300 (Data Access) at [c000000fe8217620]
pc: c00000000005d898: pnv_ioda_release_pe+0x288/0x610
lr: c00000000005dbdc: pnv_ioda_release_pe+0x5cc/0x610
sp: c000000fe82178a0
msr: 9000000000009033
dar: 10
dsisr: 40000000
current = 0xc000000fe815ab80
paca = 0xc00000000ff00400 softe: 0 irq_happened: 0x01
pid = 2709, comm = sh
Linux version 4.8.0-rc5-gavin-00006-g745efdb (gwshan@gwshan) \
(gcc version 4.9.3 (Buildroot 2016.02-rc2-00093-g5ea3bce) ) #586 SMP \
Tue Sep 6 13:37:29 AEST 2016
enter ? for help
[c000000fe8217940] c00000000005d684 pnv_ioda_release_pe+0x74/0x610
[c000000fe82179e0] c000000000034460 pcibios_release_device+0x50/0x70
[c000000fe8217a10] c0000000004aba80 pci_release_dev+0x50/0xa0
[c000000fe8217a40] c000000000704898 device_release+0x58/0xf0
[c000000fe8217ac0] c000000000470510 kobject_release+0x80/0xf0
[c000000fe8217b00] c000000000704dd4 put_device+0x24/0x40
[c000000fe8217b20] c0000000004af94c pci_remove_bus_device+0x12c/0x150
[c000000fe8217b60] c000000000034244 pci_hp_remove_devices+0x94/0xd0
[c000000fe8217ba0] c0000000004ca444 pnv_php_disable_slot+0x64/0xb0
[c000000fe8217bd0] c0000000004c88c0 power_write_file+0xa0/0x190
[c000000fe8217c50] c0000000004c248c pci_slot_attr_store+0x3c/0x60
[c000000fe8217c70] c0000000002d6494 sysfs_kf_write+0x94/0xc0
[c000000fe8217cb0] c0000000002d50f0 kernfs_fop_write+0x180/0x260
[c000000fe8217d00] c0000000002334a0 __vfs_write+0x40/0x190
[c000000fe8217d90] c000000000234738 vfs_write+0xc8/0x240
[c000000fe8217de0] c000000000236250 SyS_write+0x60/0x110
[c000000fe8217e30] c000000000009524 system_call+0x38/0x108
It fixes the kernel crash by bypassing releasing resources (DMA,
IO and memory segments, PELTM) because there are no resources assigned
to the slave PE.
Fixes: c5f7700bbd ("powerpc/powernv: Dynamically release PE")
Reported-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
When using the OPAL ICP backend we incorrectly pass Linux CPU numbers
rather than HW CPU numbers to OPAL.
Fixes: d74361881f ("powerpc/xics: Add ICP OPAL backend")
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
On ppc64le, builds with CONFIG_KEXEC=n fail with:
arch/powerpc/platforms/pseries/setup.c: In function ‘pseries_big_endian_exceptions’:
arch/powerpc/platforms/pseries/setup.c:403:13: error: implicit declaration of function ‘kdump_in_progress’
if (rc && !kdump_in_progress())
This is because pseries/setup.c includes <linux/kexec.h>, but
kdump_in_progress() is defined in <asm/kexec.h>. This is a problem
because the former only includes the latter if CONFIG_KEXEC_CORE=y.
Fix it by including <asm/kexec.h> directly, as is done in powernv/setup.c.
Fixes: d3cbff1b5a ("powerpc: Put exception configuration in a common place")
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Userspace can begin and suspend a transaction within the signal
handler which means they might enter sys_rt_sigreturn() with the
processor in suspended state.
sys_rt_sigreturn() wants to restore process context (which may have
been in a transaction before signal delivery). To do this it must
restore TM SPRS. To achieve this, any transaction initiated within the
signal frame must be discarded in order to be able to restore TM SPRs
as TM SPRs can only be manipulated non-transactionally..
>From the PowerPC ISA:
TM Bad Thing Exception [Category: Transactional Memory]
An attempt is made to execute a mtspr targeting a TM register in
other than Non-transactional state.
Not doing so results in a TM Bad Thing:
[12045.221359] Kernel BUG at c000000000050a40 [verbose debug info unavailable]
[12045.221470] Unexpected TM Bad Thing exception at c000000000050a40 (msr 0x201033)
[12045.221540] Oops: Unrecoverable exception, sig: 6 [#1]
[12045.221586] SMP NR_CPUS=2048 NUMA PowerNV
[12045.221634] 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 xt_tcpudp bridge stp llc ebtable_filter
ebtables ip6table_filter ip6_tables iptable_filter ip_tables x_tables kvm_hv kvm
uio_pdrv_genirq ipmi_powernv uio powernv_rng ipmi_msghandler autofs4 ses enclosure
scsi_transport_sas bnx2x ipr mdio libcrc32c
[12045.222167] CPU: 68 PID: 6178 Comm: sigreturnpanic Not tainted 4.7.0 #34
[12045.222224] task: c0000000fce38600 ti: c0000000fceb4000 task.ti: c0000000fceb4000
[12045.222293] NIP: c000000000050a40 LR: c0000000000163bc CTR: 0000000000000000
[12045.222361] REGS: c0000000fceb7ac0 TRAP: 0700 Not tainted (4.7.0)
[12045.222418] MSR: 9000000300201033 <SF,HV,ME,IR,DR,RI,LE,TM[SE]> CR: 28444280 XER: 20000000
[12045.222625] CFAR: c0000000000163b8 SOFTE: 0 PACATMSCRATCH: 900000014280f033
GPR00: 01100000b8000001 c0000000fceb7d40 c00000000139c100 c0000000fce390d0
GPR04: 900000034280f033 0000000000000000 0000000000000000 0000000000000000
GPR08: 0000000000000000 b000000000001033 0000000000000001 0000000000000000
GPR12: 0000000000000000 c000000002926400 0000000000000000 0000000000000000
GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
GPR20: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
GPR24: 0000000000000000 00003ffff98cadd0 00003ffff98cb470 0000000000000000
GPR28: 900000034280f033 c0000000fceb7ea0 0000000000000001 c0000000fce390d0
[12045.223535] NIP [c000000000050a40] tm_restore_sprs+0xc/0x1c
[12045.223584] LR [c0000000000163bc] tm_recheckpoint+0x5c/0xa0
[12045.223630] Call Trace:
[12045.223655] [c0000000fceb7d80] [c000000000026e74] sys_rt_sigreturn+0x494/0x6c0
[12045.223738] [c0000000fceb7e30] [c0000000000092e0] system_call+0x38/0x108
[12045.223806] Instruction dump:
[12045.223841] 7c800164 4e800020 7c0022a6 f80304a8 7c0222a6 f80304b0 7c0122a6 f80304b8
[12045.223955] 4e800020 e80304a8 7c0023a6 e80304b0 <7c0223a6> e80304b8 7c0123a6 4e800020
[12045.224074] ---[ end trace cb8002ee240bae76 ]---
It isn't clear exactly if there is really a use case for userspace
returning with a suspended transaction, however, doing so doesn't (on
its own) constitute a bad frame. As such, this patch simply discards
the transactional state of the context calling the sigreturn and
continues.
Reported-by: Laurent Dufour <ldufour@linux.vnet.ibm.com>
Signed-off-by: Cyril Bur <cyrilbur@gmail.com>
Tested-by: Laurent Dufour <ldufour@linux.vnet.ibm.com>
Reviewed-by: Laurent Dufour <ldufour@linux.vnet.ibm.com>
Acked-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
In a situation, where Linux kernel gets notified about duplicate error log
from OPAL, it is been observed that kernel fails to remove sysfs entries
(/sys/firmware/opal/elog/0xXXXXXXXX) of such error logs. This is because,
we currently search the error log/dump kobject in the kset list via
'kset_find_obj()' routine. Which eventually increment the reference count
by one, once it founds the kobject.
So, unless we decrement the reference count by one after it found the kobject,
we would not be able to release the kobject properly later.
This patch adds the 'kobject_put()' which was missing earlier.
Signed-off-by: Mukesh Ojha <mukesh02@linux.vnet.ibm.com>
Cc: stable@vger.kernel.org
Reviewed-by: Vasant Hegde <hegdevasant@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
tabort_syscall runs with RI=1, so a nested recoverable machine
check will load the paca into r13 and overwrite what we loaded
it with, because exceptions returning to privileged mode do not
restore r13.
Fixes: b4b56f9eca (powerpc/tm: Abort syscalls in active transactions)
Cc: stable@vger.kernel.org
Signed-off-by: Nick Piggin <npiggin@gmail.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
As discussed recently on the kvm mailing list, David Gibson's
intention in commit 178a787502 ("vfio: Enable VFIO device for
powerpc", 2016-02-01) was to have the KVM VFIO device built in
on all powerpc platforms. This patch adds the "select KVM_VFIO"
statement that makes this happen.
Currently, arch/powerpc/kvm/Makefile doesn't include vfio.o for
the 64-bit kvm module, because the list of objects doesn't use
the $(common-objs-y) list. The reason it doesn't is because we
don't necessarily want coalesced_mmio.o or emulate.o (for example
if HV KVM is the only target), and common-objs-y includes both.
Since this is confusing, this patch adjusts the definitions so that
we now use $(common-objs-y) in the list for the 64-bit kvm.ko
module, emulate.o is removed from common-objs-y and added in the
places that need it, and the inclusion of coalesced_mmio.o now
depends on CONFIG_KVM_MMIO.
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
MCE must not use PACA_EXGEN. When a general exception enables MSR_RI,
that means SPRN_SRR[01] and SPRN_SPRG are no longer used. However the
PACA save area is still in use.
Acked-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
When booting from an OpenFirmware which supports it, we use the
"ibm,client-architecture-support" firmware call to communicate
our capabilities to firmware.
The format of the structure we pass to firmware is specified in
PAPR (Power Architecture Platform Requirements), or the public version
LoPAPR (Linux on Power Architecture Platform Reference).
Referring to table 244 in LoPAPR v1.1, option vector 5 contains a 4 byte
field at bytes 17-20 for the "Platform Facilities Enable". This is
followed by a 1 byte field at byte 21 for "Sub-Processor Represenation
Level".
Comparing to the code, there we have the Platform Facilities
options (OV5_PFO_*) at byte 17, but we fail to pad that field out to its
full width of 4 bytes. This means the OV5_SUB_PROCESSORS option is
incorrectly placed at byte 18.
Fix it by adding zero bytes for bytes 18, 19, 20, and comment the bytes
to hopefully make it clearer in future.
As far as I'm aware nothing actually consumes this value at this time,
so the effect of this bug is nil in practice.
It does mean we've been incorrectly setting bit 15 of the "Platform
Facilities Enable" option for the past ~3 1/2 years, so we should avoid
allocating that bit to anything else in future.
Fixes: df77c79920 ("powerpc/pseries: Update ibm,architecture.vec for PAPR 2.7/POWER8")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
We observed a kernel oops when running a PPC guest with config NR_CPUS=4
and qemu option "-smp cores=1,threads=8":
[ 30.634781] Unable to handle kernel paging request for data at
address 0xc00000014192eb17
[ 30.636173] Faulting instruction address: 0xc00000000003e5cc
[ 30.637069] Oops: Kernel access of bad area, sig: 11 [#1]
[ 30.637877] SMP NR_CPUS=4 NUMA pSeries
[ 30.638471] Modules linked in:
[ 30.638949] CPU: 3 PID: 27 Comm: migration/3 Not tainted
4.7.0-07963-g9714b26 #1
[ 30.640059] task: c00000001e29c600 task.stack: c00000001e2a8000
[ 30.640956] NIP: c00000000003e5cc LR: c00000000003e550 CTR:
0000000000000000
[ 30.642001] REGS: c00000001e2ab8e0 TRAP: 0300 Not tainted
(4.7.0-07963-g9714b26)
[ 30.643139] MSR: 8000000102803033 <SF,VEC,VSX,FP,ME,IR,DR,RI,LE,TM[E]> CR: 22004084 XER: 00000000
[ 30.644583] CFAR: c000000000009e98 DAR: c00000014192eb17 DSISR: 40000000 SOFTE: 0
GPR00: c00000000140a6b8 c00000001e2abb60 c0000000016dd300 0000000000000003
GPR04: 0000000000000000 0000000000000004 c0000000016e5920 0000000000000008
GPR08: 0000000000000004 c00000014192eb17 0000000000000000 0000000000000020
GPR12: c00000000140a6c0 c00000000ffffc00 c0000000000d3ea8 c00000001e005680
GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
GPR20: 0000000000000000 c00000001e6b3a00 0000000000000000 0000000000000001
GPR24: c00000001ff85138 c00000001ff85130 000000001eb6f000 0000000000000001
GPR28: 0000000000000000 c0000000017014e0 0000000000000000 0000000000000018
[ 30.653882] NIP [c00000000003e5cc] __cpu_disable+0xcc/0x190
[ 30.654713] LR [c00000000003e550] __cpu_disable+0x50/0x190
[ 30.655528] Call Trace:
[ 30.655893] [c00000001e2abb60] [c00000000003e550] __cpu_disable+0x50/0x190 (unreliable)
[ 30.657280] [c00000001e2abbb0] [c0000000000aca0c] take_cpu_down+0x5c/0x100
[ 30.658365] [c00000001e2abc10] [c000000000163918] multi_cpu_stop+0x1a8/0x1e0
[ 30.659617] [c00000001e2abc60] [c000000000163cc0] cpu_stopper_thread+0xf0/0x1d0
[ 30.660737] [c00000001e2abd20] [c0000000000d8d70] smpboot_thread_fn+0x290/0x2a0
[ 30.661879] [c00000001e2abd80] [c0000000000d3fa8] kthread+0x108/0x130
[ 30.662876] [c00000001e2abe30] [c000000000009968] ret_from_kernel_thread+0x5c/0x74
[ 30.664017] Instruction dump:
[ 30.664477] 7bde1f24 38a00000 787f1f24 3b600001 39890008 7d204b78 7d05e214 7d0b07b4
[ 30.665642] 796b1f24 7d26582a 7d204a14 7d29f214 <7d4048a8> 7d4a3878 7d4049ad 40c2fff4
[ 30.666854] ---[ end trace 32643b7195717741 ]---
The reason of this is that in __cpu_disable(), when we try to set the
cpu_sibling_mask or cpu_core_mask of the sibling CPUs of the disabled
one, we don't check whether the current configuration employs those
sibling CPUs(hw threads). And if a CPU is not employed by a
configuration, the percpu structures cpu_{sibling,core}_mask are not
allocated, therefore accessing those cpumasks will result in problems as
above.
This patch fixes this problem by adding an addition check on whether the
id is no less than nr_cpu_ids in the sibling CPU iteration code.
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
These files were only including module.h for exception table
related functions. We've now separated that content out into its
own file "extable.h" so now move over to that and avoid all the
extra header content in module.h that we don't really need to compile
these files.
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Unsigned type is always non-negative, so the loop could not end in case
condition is never true.
The problem has been detected using semantic patch
scripts/coccinelle/tests/unsigned_lesser_than_zero.cocci
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This patch leverages 'struct pci_host_bridge' from the PCI subsystem
in order to free the pci_controller only after the last reference to
its devices is dropped (avoiding an oops in pcibios_release_device()
if the last reference is dropped after pcibios_free_controller()).
The patch relies on pci_host_bridge.release_fn() (and .release_data),
which is called automatically by the PCI subsystem when the root bus
is released (i.e., the last reference is dropped). Those fields are
set via pci_set_host_bridge_release() (e.g. in the platform-specific
implementation of pcibios_root_bridge_prepare()).
It introduces the 'pcibios_free_controller_deferred()' .release_fn()
and it expects .release_data to hold a pointer to the pci_controller.
The function implictly calls 'pcibios_free_controller()', so an user
must *NOT* explicitly call it if using the new _deferred() callback.
The functionality is enabled for pseries (although it isn't platform
specific, and may be used by cxl).
Details on not-so-elegant design choices:
- Use 'pci_host_bridge.release_data' field as pointer to associated
'struct pci_controller' so *not* to 'pci_bus_to_host(bridge->bus)'
in pcibios_free_controller_deferred().
That's because pci_remove_root_bus() sets 'host_bridge->bus = NULL'
(so, if the last reference is released after pci_remove_root_bus()
runs, which eventually reaches pcibios_free_controller_deferred(),
that would hit a null pointer dereference).
The cxl/vphb.c code calls pci_remove_root_bus(), and the cxl folks
are interested in this fix.
Test-case #1 (hold references)
# ls -ld /sys/block/sd* | grep -m1 0021:01:00.0
<...> /sys/block/sdaa -> ../devices/pci0021:01/0021:01:00.0/<...>
# ls -ld /sys/block/sd* | grep -m1 0021:01:00.1
<...> /sys/block/sdab -> ../devices/pci0021:01/0021:01:00.1/<...>
# cat >/dev/sdaa & pid1=$!
# cat >/dev/sdab & pid2=$!
# drmgr -w 5 -d 1 -c phb -s 'PHB 33' -r
Validating PHB DLPAR capability...yes.
[ 594.306719] pci_hp_remove_devices: PCI: Removing devices on bus 0021:01
[ 594.306738] pci_hp_remove_devices: Removing 0021:01:00.0...
...
[ 598.236381] pci_hp_remove_devices: Removing 0021:01:00.1...
...
[ 611.972077] pci_bus 0021:01: busn_res: [bus 01-ff] is released
[ 611.972140] rpadlpar_io: slot PHB 33 removed
# kill -9 $pid1
# kill -9 $pid2
[ 632.918088] pcibios_free_controller_deferred: domain 33, dynamic 1
Test-case #2 (don't hold references)
# drmgr -w 5 -d 1 -c phb -s 'PHB 33' -r
Validating PHB DLPAR capability...yes.
[ 916.357363] pci_hp_remove_devices: PCI: Removing devices on bus 0021:01
[ 916.357386] pci_hp_remove_devices: Removing 0021:01:00.0...
...
[ 920.566527] pci_hp_remove_devices: Removing 0021:01:00.1...
...
[ 933.955873] pci_bus 0021:01: busn_res: [bus 01-ff] is released
[ 933.955977] pcibios_free_controller_deferred: domain 33, dynamic 1
[ 933.955999] rpadlpar_io: slot PHB 33 removed
Suggested-By: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>
Reviewed-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Tested-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> # cxl
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The field "owner" is set by the core.
Thus delete an unneeded initialisation.
Generated by: scripts/coccinelle/api/platform_no_drv_owner.cocci
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The field "owner" is set by the core.
Thus delete an unneeded initialisation.
Generated by: scripts/coccinelle/api/platform_no_drv_owner.cocci
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Powerpc builds may fail with the following build error.
Error log:
In file included from ./arch/powerpc/include/asm/mmu_context.h:11:0,
from ./include/linux/mmu_context.h:4,
from mm/mmu_context.c:8:
./arch/powerpc/include/asm/cputhreads.h: In function 'get_tensr':
./arch/powerpc/include/asm/cputhreads.h:101:2: error:
implicit declaration of function 'cpu_has_feature'
The problem can be triggered by configuring ppc64e_defconfig and selecting
CONFIG_TICK_CPU_ACCOUNTING instead of CONFIG_VIRT_CPU_ACCOUNTING_NATIVE.
Fixes: b92a226e52 ("powerpc: Move cpu_has_feature() to a separate file")
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
It doesn't make sense to create irqfds for a VM that doesn't have
in-kernel interrupt controller emulation. There is an existing
interface for architecture code to tell the irqfd code whether or
not any interrupt controller has been initialized, called
kvm_arch_intc_initialized(), so let's implement that for powerpc.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
It turns out that if userspace creates a pseries-type VM without
in-kernel XICS (interrupt controller) emulation, and then connects
an eventfd to the VM as an irqfd, and the eventfd gets signalled,
that the code will try to deliver an interrupt via the non-existent
XICS object and crash the host kernel with a NULL pointer dereference.
To fix this, we check for the presence of the XICS object before
trying to deliver the interrupt, and return with an error if not.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Pull KVM fixes from Radim Krčmář:
"KVM:
- lock kvm_device list to prevent corruption on device creation.
PPC:
- split debugfs initialization from creation of the xics device to
unlock the newly taken kvm lock earlier.
s390:
- prevent userspace from triggering two WARN_ON_ONCE.
MIPS:
- fix several issues in the management of TLB faults (Cc: stable)"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
MIPS: KVM: Propagate kseg0/mapped tlb fault errors
MIPS: KVM: Fix gfn range check in kseg0 tlb faults
MIPS: KVM: Add missing gfn range check
MIPS: KVM: Fix mapped fault broken commpage handling
KVM: Protect device ops->create and list_add with kvm->lock
KVM: PPC: Move xics_debugfs_init out of create
KVM: s390: reset KVM_REQ_MMU_RELOAD if mapping the prefix failed
KVM: s390: set the prefix initially properly
Pull powerpc fixes from Michael Ellerman:
"Some powerpc fixes for 4.8:
Misc:
- powerpc/vdso: Fix build rules to rebuild vdsos correctly from Nicholas Piggin
- powerpc/ptrace: Fix coredump since ptrace TM changes from Cyril Bur
- powerpc/32: Fix csum_partial_copy_generic() from Christophe Leroy
- cxl: Set psl_fir_cntl to production environment value from Frederic Barrat
- powerpc/eeh: Switch to conventional PCI address output in EEH log from Guilherme G. Piccoli
- cxl: Use fixed width predefined types in data structure. from Philippe Bergheaud
- powerpc/vdso: Add missing include file from Guenter Roeck
- powerpc: Fix unused function warning 'lmb_to_memblock' from Alastair D'Silva
- powerpc/powernv/ioda: Fix TCE invalidate to work in real mode again from Alexey Kardashevskiy
- powerpc/cell: Add missing error code in spufs_mkgang() from Dan Carpenter
- crypto: crc32c-vpmsum - Convert to CPU feature based module autoloading from Anton Blanchard
- powerpc/pasemi: Fix coherent_dma_mask for dma engine from Darren Stevens
Benjamin Herrenschmidt:
- powerpc/32: Fix crash during static key init
- powerpc: Update obsolete comment in setup_32.c about early_init()
- powerpc: Print the kernel load address at the end of prom_init()
- powerpc/pnv/pci: Fix incorrect PE reservation attempt on some 64-bit BARs
- powerpc/xics: Properly set Edge/Level type and enable resend
Mahesh Salgaonkar:
- powerpc/book3s: Fix MCE console messages for unrecoverable MCE.
- powerpc/powernv: Fix MCE handler to avoid trashing CR0/CR1 registers.
- powerpc/powernv: Move IDLE_STATE_ENTER_SEQ macro to cpuidle.h
- powerpc/powernv: Load correct TOC pointer while waking up from winkle.
Andrew Donnellan:
- cxl: Fix sparse warnings
- cxl: Fix NULL dereference in cxl_context_init() on PowerVM guests
Michael Ellerman:
- selftests/powerpc: Specify we expect to build with std=gnu99
- powerpc/Makefile: Use cflags-y/aflags-y for setting endian options
- powerpc/pci: Fix endian bug in fixed PHB numbering"
* tag 'powerpc-4.8-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (26 commits)
selftests/powerpc: Specify we expect to build with std=gnu99
powerpc/vdso: Fix build rules to rebuild vdsos correctly
powerpc/Makefile: Use cflags-y/aflags-y for setting endian options
powerpc/32: Fix crash during static key init
powerpc: Update obsolete comment in setup_32.c about early_init()
powerpc: Print the kernel load address at the end of prom_init()
powerpc/ptrace: Fix coredump since ptrace TM changes
powerpc/32: Fix csum_partial_copy_generic()
cxl: Set psl_fir_cntl to production environment value
powerpc/pnv/pci: Fix incorrect PE reservation attempt on some 64-bit BARs
powerpc/book3s: Fix MCE console messages for unrecoverable MCE.
powerpc/pci: Fix endian bug in fixed PHB numbering
powerpc/eeh: Switch to conventional PCI address output in EEH log
cxl: Fix sparse warnings
cxl: Fix NULL dereference in cxl_context_init() on PowerVM guests
cxl: Use fixed width predefined types in data structure.
powerpc/vdso: Add missing include file
powerpc: Fix unused function warning 'lmb_to_memblock'
powerpc/powernv: Fix MCE handler to avoid trashing CR0/CR1 registers.
powerpc/powernv: Move IDLE_STATE_ENTER_SEQ macro to cpuidle.h
...
KVM devices were manipulating list data structures without any form of
synchronization, and some implementations of the create operations also
suffered from a lack of synchronization.
Now when we've split the xics create operation into create and init, we
can hold the kvm->lock mutex while calling the create operation and when
manipulating the devices list.
The error path in the generic code gets slightly ugly because we have to
take the mutex again and delete the device from the list, but holding
the mutex during anon_inode_getfd or releasing/locking the mutex in the
common non-error path seemed wrong.
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
As we are about to hold the kvm->lock during the create operation on KVM
devices, we should move the call to xics_debugfs_init into its own
function, since holding a mutex over extended amounts of time might not
be a good idea.
Introduce an init operation on the kvm_device_ops struct which cannot
fail and call this, if configured, after the device has been created.
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
When using if_changed, we need to add FORCE as a dependency (see
Documentation/kbuild/makefiles.txt) otherwise we don't get command line
change checking amongst other things. This has resulted in vdsos not
being rebuilt when switching between big and little endian.
The vdso64/32ld commands have to be changed around to avoid pulling
FORCE into the linker command line (code copied from x86).
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
When we introduced the little endian support, we added the endian flags
to CC directly using override. I don't know the history of why we did
that, I suspect no one does.
Although this mostly works, it has one bug, which is that CROSS32CC
doesn't get -mbig-endian. That means when the compiler is little endian
by default and the user is building big endian, vdso32 is incorrectly
compiled as little endian and the kernel fails to build.
Instead we can add the endian flags to cflags-y/aflags-y, and then
append those to KBUILD_CFLAGS/KBUILD_AFLAGS.
This has the advantage of being 1) less ugly, 2) the documented way of
adding flags in the arch Makefile and 3) it fixes building vdso32 with a
LE toolchain.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
We cannot do those initializations from apply_feature_fixups() as
this function runs in a very restricted environment on 32-bit where
the kernel isn't running at its linked address and the PTRRELOC()
macro must be used for any global accesss.
Instead, split them into a separtate steup_feature_keys() function
which is called in a more suitable spot on ppc32.
Fixes: 309b315b6e ("powerpc: Call jump_label_init() in apply_feature_fixups()")
Reported-and-tested-by: Christian Kujau <lists@nerdbynature.de>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This makes it easier to debug crashes that happen very early before
the kernel takes over Open Firmware by allowing us to relate the OF
reported crashing addresses to offsets within the kernel.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Commit 8d460f6156 ("powerpc/process: Add the function
flush_tmregs_to_thread") added flush_tmregs_to_thread() and included
the assumption that it would only be called for a task which is not
current.
Although this is correct for ptrace, when generating a core dump, some
of the routines which call flush_tmregs_to_thread() are called. This
leads to a WARNing such as:
Not expecting ptrace on self: TM regs may be incorrect
------------[ cut here ]------------
WARNING: CPU: 123 PID: 7727 at arch/powerpc/kernel/process.c:1088 flush_tmregs_to_thread+0x78/0x80
CPU: 123 PID: 7727 Comm: libvirtd Not tainted 4.8.0-rc1-gcc6x-g61e8a0d #1
task: c000000fe631b600 task.stack: c000000fe63b0000
NIP: c00000000001a1a8 LR: c00000000001a1a4 CTR: c000000000717780
REGS: c000000fe63b3420 TRAP: 0700 Not tainted (4.8.0-rc1-gcc6x-g61e8a0d)
MSR: 900000010282b033 <SF,HV,VEC,VSX,EE,FP,ME,IR,DR,RI,LE,TM[E]> CR: 28004222 XER: 20000000
...
NIP [c00000000001a1a8] flush_tmregs_to_thread+0x78/0x80
LR [c00000000001a1a4] flush_tmregs_to_thread+0x74/0x80
Call Trace:
flush_tmregs_to_thread+0x74/0x80 (unreliable)
vsr_get+0x64/0x1a0
elf_core_dump+0x604/0x1430
do_coredump+0x5fc/0x1200
get_signal+0x398/0x740
do_signal+0x54/0x2b0
do_notify_resume+0x98/0xb0
ret_from_except_lite+0x70/0x74
So fix flush_tmregs_to_thread() to detect the case where it is called on
current, and a transaction is active, and in that case flush the TM regs
to the thread_struct.
This patch also moves flush_tmregs_to_thread() into ptrace.c as it is
only called from that file.
Fixes: 8d460f6156 ("powerpc/process: Add the function flush_tmregs_to_thread")
Signed-off-by: Cyril Bur <cyrilbur@gmail.com>
[mpe: Flesh out change log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Commit 7aef413656 ("powerpc32: rewrite csum_partial_copy_generic()
based on copy_tofrom_user()") introduced a bug when destination
address is odd and initial csum is not null
In that (rare) case the initial csum value has to be rotated one byte
as well as the resulting value is
This patch also fixes related comments
Fixes: 7aef413656 ("powerpc32: rewrite csum_partial_copy_generic() based on copy_tofrom_user()")
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The generic allocation code may sometimes decide to assign a prefetchable
64-bit BAR to the M32 window. In fact it may also decide to allocate
a 64-bit non-prefetchable BAR to the M64 one ! So using the resource
flags as a test to decide which window was used for PE allocation is
just wrong and leads to insane PE numbers.
Instead, compare the addresses to figure it out.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
[mpe: Rename the function as agreed by Ben & Gavin]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
When machine check occurs with MSR(RI=0), it means MC interrupt is
unrecoverable and kernel goes down to panic path. But the console
message still shows it as recovered. This patch fixes the MCE console
messages.
Fixes: 36df96f8ac ("powerpc/book3s: Decode and save machine check event.")
Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The recent commit 63a72284b1 ("powerpc/pci: Assign fixed PHB number
based on device-tree properties"), added code to read a 64-bit property
from the device tree, and if not found read a 32-bit property (reg).
There was a bug in the 32-bit case, on big endian machines, due to the
use of the 64-bit value to read the 32-bit property. The cast of &prop
means we end up writing to the high 32-bit of prop, leaving the low
32-bits containing whatever junk was on the stack.
If that junk value was non-zero, and < MAX_PHBS, we would end up using
it as the PHB id. This results in users seeing what appear to be random
PHB ids.
Fix it by reading into a u32 property and then assigning that to the
u64 value, letting the CPU do the correct conversions for us.
Fixes: 63a72284b1 ("powerpc/pci: Assign fixed PHB number based on device-tree properties")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This is a very minor/trivial fix for the output of PCI address on EEH
logs. The PCI address on "OF node" field currently is using ":" as a
separator for the function, but the usual separator is ".". This patch
changes the separator to dot, so the PCI address is printed as usual.
Signed-off-by: Guilherme G. Piccoli <gpiccoli@linux.vnet.ibm.com>
Reviewed-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Some powerpc builds fail with the following buld error.
In file included from ./arch/powerpc/include/asm/mmu_context.h:11:0,
from arch/powerpc/kernel/vdso.c:28:
arch/powerpc/include/asm/cputhreads.h: In function 'get_tensr':
arch/powerpc/include/asm/cputhreads.h:101:2: error:
implicit declaration of function 'cpu_has_feature'
Fixes: b92a226e52 ("powerpc: Move cpu_has_feature() to a separate file")
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This patch fixes the following warning:
arch/powerpc/platforms/pseries/hotplug-memory.c:323:29: error: 'lmb_to_memblock' defined but not used [-Werror=unused-function]
static struct memory_block *lmb_to_memblock(struct of_drconf_cell *lmb)
^~~~~~~~~~~~~~~
The only consumer of this function is 'dlpar_remove_lmb', which is
enabled with CONFIG_MEMORY_HOTREMOVE, so move it into the same
ifdef block.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The current implementation of MCE early handling modifies CR0/1 registers
without saving its old values. Fix this by moving early check for
powersaving mode to machine_check_handle_early().
The power architecture 2.06 or later allows the possibility of getting
machine check while in nap/sleep/winkle. The last bit of HSPRG0 is set
to 1, if thread is woken up from winkle. Hence, clear the last bit of
HSPRG0 (r13) before MCE handler starts using it as paca pointer.
Also, the current code always puts the thread into nap state irrespective
of whatever idle state it woke up from. Fix that by looking at
paca->thread_idle_state and put the thread back into same state where it
came from.
Fixes: 1c51089f77 ("powerpc/book3s: Return from interrupt if coming from evil context.")
Reported-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Reviewed-by: Shreyas B. Prabhu <shreyas@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Move IDLE_STATE_ENTER_SEQ macro to cpuidle.h so that MCE handler changes
in subsequent patch can use it.
No functionality change.
Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The function pnv_restore_hyp_resource() loads the TOC into r2 from
the invalid PACA pointer before fixing r13 value. This do not affect
POWER ISA 3.0 but it does have an impact on POWER ISA 2.07 or less
leading CPU to get stuck forever.
login: [ 471.830433] Processor 120 is stuck.
This can be easily reproducible using following steps:
- Turn off SMT
$ ppc64_cpu --smt=off
- offline/online any online cpu (Thread 0 of any core which is online)
$ echo 0 > /sys/devices/system/cpu/cpu<num>/online
$ echo 1 > /sys/devices/system/cpu/cpu<num>/online
For POWER ISA 2.07 or less, the last bit of HSPRG0 is set indicating
that thread is waking up from winkle. Hence, the last bit of HSPRG0(r13)
needs to be clear before accessing it as PACA to avoid loading invalid
values from invalid PACA pointer.
Fix this by loading TOC after r13 register is corrected.
Fixes: bcef83a00d ("powerpc/powernv: Add platform support for stop instruction")
Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Acked-by: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Commit fd141d1a99 ("powerpc/powernv/pci: Rework accessing the TCE
invalidate register") broke TCE invalidation on IODA2/PHB3 for real
mode.
This makes invalidate work again.
Fixes: fd141d1a99 ("powerpc/powernv/pci: Rework accessing the TCE invalidate register")
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
