powerpc/mm/hugetlb: Allow runtime allocation of 16G.
Now that we have GIGANTIC_PAGE enabled on powerpc, use this for 16G hugepages
with hash translation mode. Depending on the total system memory we have, we may
be able to allocate 16G hugepages runtime. This also remove the hugetlb setup
difference between hash/radix translation mode.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc/mm/hugetlb: Add support for reserving gigantic huge pages via kernel command line
With commit aa888a74977a8 ("hugetlb: support larger than MAX_ORDER") we added
support for allocating gigantic hugepages via kernel command line. Switch
ppc64 arch specific code to use that.
W.r.t FSL support, we now limit our allocation range using BOOTMEM_ALLOC_ACCESSIBLE.
We use the kernel command line to do reservation of hugetlb pages on powernv
platforms. On pseries hash mmu mode the supported gigantic huge page size is
16GB and that can only be allocated with hypervisor assist. For pseries the
command line option doesn't do the allocation. Instead pseries does gigantic
hugepage allocation based on hypervisor hint that is specified via
"ibm,expected#pages" property of the memory node.
Cc: Scott Wood <oss@buserror.net> Cc: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
mm/hugetlb: Allow arch to override and call the weak function
When running in guest mode ppc64 supports a different mechanism for hugetlb
allocation/reservation. The LPAR management application called HMC can
be used to reserve a set of hugepages and we pass the details of
reserved pages via device tree to the guest. (more details in
htab_dt_scan_hugepage_blocks()) . We do the memblock_reserve of the range
and later in the boot sequence, we add the reserved range to huge_boot_pages.
But to enable 16G hugetlb on baremetal config (when we are not running as guest)
we want to do memblock reservation during boot. Generic code already does this
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc/hugetlb: fix page rights verification in gup_hugepte()
gup_hugepte() checks if pages are present and readable, and
when 'write' is set, also checks if the pages are writable.
Initially this was done by checking if _PAGE_PRESENT and
_PAGE_READ were set. In addition, _PAGE_WRITE was verified for write
accesses.
The problem is that we have to handle the three following cases:
1/ The target defines __PAGE_READ and __PAGE_WRITE
2/ The target defines __PAGE_RW
3/ The target defines __PAGE_RO
In case 1/, this is obvious
In case 2/, __PAGE_READ is defined as 0 and __PAGE_WRITE as __PAGE_RW
so it works as well.
But in case 3, __PAGE_RW is defined as 0, which means __PAGE_WRITE is 0
and then the test returns true (page writable) in all cases.
A first correction was attempted in commit 6b8cb66a6a7cc ("powerpc: Fix
usage of _PAGE_RO in hugepage"), but that fix is wrong:
instead of checking that the page is writable when write is requested,
it checks that the page is NOT writable when write is NOT requested.
This patch adds a new pte_read() helper to check whether a page is
readable or not. This avoids handling all possible cases in
gup_hugepte().
Then gup_hugepte() is modified to use pte_present(), pte_read()
and pte_write() instead of the raw flags.
__set_fixmap() uses __fix_to_virt() then does the boundary checks
by it self. Instead, we can use fix_to_virt() which does the
verification at build time. For this, we need to use it inline
so that GCC can see the real value of idx at buildtime.
In the meantime, we remove the 'fixmaps' variable.
This variable is set but has never been used from the beginning
(commit 2c419bdeca1d9 ("[POWERPC] Port fixmap from x86 and use
for kmap_atomic"))
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc/32: Avoid risk of unrecoverable TLBmiss inside entry_32.S
By default, the 8xx pins an ITLB on the first 8M of memory in order
to avoid any ITLB miss on kernel code.
However, with some debug functions like DEBUG_PAGEALLOC and
DEBUG_RODATA, pinning TLBs is contradictory.
In order to avoid any ITLB miss in a critical section without pinning
TLBs, we have to ensure that there is no page boundary crossed between
the setup of a new value in SRR0/SRR1 and the associated RFI.
The functions modifying srr0/srr1 are all located in setup_32.S.
They are spread over almost 4kbytes.
The patch forces a 12 bits (4kbytes) alignment for those
functions. This garanties that the functions remain in a
single 4k page.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc/8xx: Remove macro that checks kernel address
The macro to check if an address is a kernel address or not is
not used anymore in DTLBmiss handler. It is used in ITLB miss handler
and in DTLB error handler. DTLB error handler is not a hot path, it
doesn't need such optimisation.
In order to simplify a following patch which will rework ITLB miss
handler, we remove the macros and reintroduce them inside the handler.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Julia Lawall [Sun, 13 Aug 2017 13:24:23 +0000 (15:24 +0200)]
powerpc/chrp: Store the intended structure
Normally the values in the resource field and the argument to ARRAY_SIZE
in the num_resources are the same. In this case, the value in the reousrce
field is the same as the one in the previous platform_device structure, and
appears to be a copy-paste error. Replace the value in the resource field
with the argument to the local call to ARRAY_SIZE.
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc/iommu: Avoid undefined right shift in iommu_range_alloc()
In iommu_range_alloc() we generate a mask by right shifting ~0,
however if the specified alignment is 0 then we right shift by 64,
which is undefined. UBSAN tells us so:
UBSAN: Undefined behaviour in ../arch/powerpc/kernel/iommu.c:193:35
shift exponent 64 is too large for 64-bit type 'long unsigned int'
We can avoid it by instead generating the mask with:
align_mask = (1ull << align_order) - 1;
That will also generate an undefined shift if align_order is 64 or
greater, but that shouldn't be a problem for a while.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Anju T [Mon, 14 Aug 2017 11:42:23 +0000 (17:12 +0530)]
powerpc/perf/imc: Fix nest events on muti socket system
In a multi node system with discontiguous node ids, nest event values
are not showing up properly. eg. lscpu output:
NUMA node0 CPU(s): 0-15
NUMA node8 CPU(s): 16-31
Nest event values on such systems can be counted on CPUs <= 15:
$./perf stat -e 'nest_powerbus0_imc/PM_PB_CYC/' -C 0-14 -I 1000 sleep 1000
# time counts unit events
1.000294577 30,17,24,42,880 nest_powerbus0_imc/PM_PB_CYC/
But not on CPUs >= 16:
$./perf stat -e 'nest_powerbus0_imc/PM_PB_CYC/' -C 16-28 -I 1000 sleep 1000
# time counts unit events
1.000049902 <not supported> nest_powerbus0_imc/PM_PB_CYC/
This is because, when fetching the reference count, the node id (which
may be sparse) is used as the array index, not the node number (which
is 0 based and contiguous).
Fix it by using the node number as the array index.
$./perf stat -e 'nest_powerbus0_imc/PM_PB_CYC/' -C 16-28 -I 1000 sleep 1000
# time counts unit events
1.000241961 26,12,35,28,704 nest_powerbus0_imc/PM_PB_CYC/
Signed-off-by: Anju T Sudhakar <anju@linux.vnet.ibm.com>
[mpe: Change log tweaks for clarity and brevity] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
[mpe: Use $(subst ..) on KBUILD_CFLAGS rather than CFLAGS_REMOVE_xxx] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Breno Leitao [Wed, 2 Aug 2017 20:14:06 +0000 (17:14 -0300)]
powerpc/xmon: Disable tracing when entering xmon
If tracing is enabled and you get into xmon, the tracing buffer
continues to be updated, causing possible loss of data and unnecessary
tracing information coming from xmon functions.
This patch simple disables tracing when entering xmon, and re-enables it
if the kernel is resumed (with 'x').
Signed-off-by: Breno Leitao <leitao@debian.org> Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Breno Leitao [Wed, 2 Aug 2017 20:14:05 +0000 (17:14 -0300)]
powerpc/xmon: Dump ftrace buffers for the current CPU only
Current xmon 'dt' command dumps the tracing buffer for all the CPUs,
which makes it very hard to read due to the fact that most of
powerpc machines currently have many CPUs. Other than that, the CPU
lines are interleaved in the ftrace log.
This new option just dumps the ftrace buffer for the current CPU.
Signed-off-by: Breno Leitao <leitao@debian.org> Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Bhumika Goyal [Fri, 11 Aug 2017 17:38:45 +0000 (23:08 +0530)]
drivers/macintosh: Make wf_control_ops and wf_pid_param const
Make wf_control_ops const as they are only stored in the ops field of a
wf_control structure, which is const.
Make wf_pid_param const as they are only used during a copy operation.
Done using Coccinelle.
Signed-off-by: Bhumika Goyal <bhumirks@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Dan Carpenter [Fri, 11 Aug 2017 20:05:41 +0000 (23:05 +0300)]
powerpc/perf: Fix double unlock in imc_common_cpuhp_mem_free()
This function is not called with the nest_init_lock held, and it also
unlocks the nest_init_lock immediately below, so it's fairly clear
that this is a typo and should be locking the lock.
Fixes: 885dcd709ba9 ("powerpc/perf: Add nest IMC PMU support") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Christophe Leroy [Mon, 14 Aug 2017 07:14:19 +0000 (09:14 +0200)]
powerpc/8xx: Fix two CONFIG_8xx left behind
Commit 968159c0031ac ("powerpc/8xx: Getting rid of remaining use of
CONFIG_8xx") removed all but 2 references to 8xx in Kconfigs.
This patch removes the two remaining ones.
Fixes: 968159c0031a ("powerpc/8xx: Getting rid of remaining use of CONFIG_8xx") Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Two config options exist to define powerpc MPC8xx:
* CONFIG_PPC_8xx
* CONFIG_8xx
arch/powerpc/platforms/Kconfig.cputype has contained the following
comment about CONFIG_8xx item for some years:
"# this is temp to handle compat with arch=ppc"
There is no more users of CONFIG_8xx, so remove it.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc/8xx: Getting rid of remaining use of CONFIG_8xx
Two config options exist to define powerpc MPC8xx:
* CONFIG_PPC_8xx
* CONFIG_8xx
arch/powerpc/platforms/Kconfig.cputype has contained the following
comment about CONFIG_8xx item for some years:
"# this is temp to handle compat with arch=ppc"
arch/powerpc is now the only place with remaining use of
CONFIG_8xx: get rid of them.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Since commit aa42c69c67f82 ("[POWERPC] Add support for FP emulation
for the e300c2 core"), program_check_exception() can be called for
math emulation. In that case, 'reason' is 0.
On the 8xx, there is a Software Emulation interrupt which is
called for all unimplemented and illegal instructions. This
interrupt calls SoftwareEmulation() which does almost the
same as program_check_exception() called with reason = 0.
The Software Emulation interrupt sets all reason bits to 0,
it is therefore possible to call program_check_exception()
directly from the interrupt handler.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc/8xx: Simplify CONFIG_8xx checks in Makefile
The entire 8xx directory is omitted if CONFIG_8xx is not enabled, so
within the 8xx/Makefile CONFIG_8xx is always y. So convert
obj-$(CONFIG_8xx) to the more obvious obj-y.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc/4xx: Move machine_check_4xx() into platforms/4xx
Now that we have 4xx platform directory we can move the 4xx machine
check handler in there. Again we drop get_mc_reason() and replace it
with regs->dsisr directly (which is actually SPRN_ESR).
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc/4xx: Create 4xx pseudo-platform in platforms/4xx
We have a lot of code in sysdev for supporting 4xx, ie. either 40x or
44x. Instead it would be cleaner if it was all in platforms/4xx.
This is slightly odd in that we don't actually define any machines in
the 4xx platform, as is usual for a platform directory. But still it
seems like a better result to have all this related code in a directory
by itself.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc/44x: Move 44x machine check handlers into platforms/44x
We have several 44x machine check handlers defined in traps.c. It would
be preferable if they were split out with the platforms that use them.
Do that.
In the process, drop get_mc_reason() and instead just open code the
lookup of reason from regs->dsisr. This avoids a pointless layer of
abstraction.
We know to use regs->dsisr because 44x enables BOOKE which enables
PPC_ADV_DEBUG_REGS, and FSL_BOOKE is not enabled on 44x builds.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc/44x: Simplify CONFIG_44x checks in Makefile
The entire 44x directory is omitted if CONFIG_44x is not enabled, so
within the 44x/Makefile CONFIG_44x is always y. So convert
obj-$(CONFIG_44x) to the more obvious obj-y.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc/47x: Guard 47x cputable entries with CONFIG_PPC_47x
Currently we build the 47x cputable entries even when CONFIG_PPC_47x is
disabled. That means a kernel built without CONFIG_PPC_47x will claim to
support a 47x CPU and start booting, only to break somewhere later
because it doesn't have 47x support compiled in.
So guard the 47x cputable entries with CONFIG_PPC_47x. Note that this is
inside the #ifdef CONFIG_44x section, because 47x depends on 44x.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Shilpasri G Bhat [Thu, 10 Aug 2017 03:31:20 +0000 (09:01 +0530)]
powerpc/powernv: Add support to clear sensor groups data
Adds support for clearing different sensor groups. OCC inband sensor
groups like CSM, Profiler, Job Scheduler can be cleared using this
driver. The min/max of all sensors belonging to these sensor groups
will be cleared.
Signed-off-by: Shilpasri G Bhat <shilpa.bhat@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Shilpasri G Bhat [Thu, 10 Aug 2017 03:31:19 +0000 (09:01 +0530)]
powerpc/powernv: Add support to set power-shifting-ratio
This patch adds support to set power-shifting-ratio which hints the
firmware how to distribute/throttle power between different entities
in a system (e.g CPU v/s GPU). This ratio is used by OCC for power
capping algorithm.
Signed-off-by: Shilpasri G Bhat <shilpa.bhat@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Nicholas Piggin [Fri, 21 Jul 2017 01:16:44 +0000 (11:16 +1000)]
powerpc/pseries: Don't print failure message in energy driver
This driver currently reports the H_BEST_ENERGY hypervisor call is
unsupported (even when booting in a non-virtualised environment). This
is not something the administrator can do much with, and not
significant for debugging.
Remove it.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Matt Brown [Mon, 31 Jul 2017 00:58:26 +0000 (10:58 +1000)]
powerpc/lib/sstep: Add isel instruction emulation
This adds emulation for the isel instruction.
Tested for correctness against the isel instruction and its extended
mnemonics (lt, gt, eq) on ppc64le.
Signed-off-by: Matt Brown <matthew.brown.dev@gmail.com> Reviewed-by: Cyril Bur <cyrilbur@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Matt Brown [Mon, 31 Jul 2017 00:58:25 +0000 (10:58 +1000)]
powerpc/lib/sstep: Add prty instruction emulation
This adds emulation for the prtyw and prtyd instructions.
Tested for logical correctness against the prtyw and prtyd instructions
on ppc64le.
Signed-off-by: Matt Brown <matthew.brown.dev@gmail.com> Reviewed-by: Cyril Bur <cyrilbur@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This adds emulation for the bpermd instruction.
Tested for correctness against the bpermd instruction on ppc64le.
Signed-off-by: Matt Brown <matthew.brown.dev@gmail.com> Reviewed-by: Cyril Bur <cyrilbur@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This adds emulations for the popcntb, popcntw, and popcntd instructions.
Tested for correctness against the popcnt{b,w,d} instructions on ppc64le.
Signed-off-by: Matt Brown <matthew.brown.dev@gmail.com> Reviewed-by: Cyril Bur <cyrilbur@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Matt Brown [Mon, 31 Jul 2017 00:58:22 +0000 (10:58 +1000)]
powerpc/lib/sstep: Add cmpb instruction emulation
This patch adds emulation of the cmpb instruction, enabling xmon to
emulate this instruction.
Tested for correctness against the cmpb asm instruction on ppc64le.
Signed-off-by: Matt Brown <matthew.brown.dev@gmail.com> Reviewed-by: Cyril Bur <cyrilbur@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc/perf: Add PM_LD_MISS_L1 and PM_BR_2PATH to power9 event list
Add couple of more events (PM_LD_MISS_L1 and PM_BR_2PATH) to
power9 event list and power9_event_alternatives array (these
events can be counted in more than one PMC).
Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc/perf: Factor out PPMU_ONLY_COUNT_RUN check code from power8
There are some hardware events on Power systems which only count when
the processor is not idle, and there are some fixed-function counters
which count such events. For example, the "run cycles" event counts
cycles when the processor is not idle. If the user asks to count
cycles, we can use "run cycles" if this is a per-task event, since the
processor is running when the task is running, by definition. We can't
use "run cycles" if the user asks for "cycles" on a system-wide
counter.
Currently in power8 this check is done using PPMU_ONLY_COUNT_RUN flag
in power8_get_alternatives() function. Based on the flag, events are
switched if needed. This function should also be enabled in power9, so
factor out the code to isa207_get_alternatives().
Fixes: efe881afdd999 ('powerpc/perf: Factor out event_alternative function') Reported-by: Anton Blanchard <anton@samba.org> Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc/perf: Update default sdar_mode value for power9
Commit 20dd4c624d251 ('powerpc/perf: Fix SDAR_MODE value for continous
sampling on Power9') set the default sdar_mode value in MMCRA[SDAR_MODE]
to be used as 0b01 (Update on TLB miss). And this value is set if sdar_mode
from event is zero, or we are in continous sampling mode in power9 dd1.
But it is preferred to have the sdar_mode value for power9 as
0b10 (Update on dcache miss) for better sampling updates instead
of 0b01 (Update on TLB miss).
From Anton:
Using a bandwidth test case with a 1MB footprint, I profiled cycles and
chose TLB updates of the SDAR:
I get 5217 unique addresses. No surprises here, but it does show why
TLB misses is the wrong event to default to - we get very little useful
information out of it.
Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com> Acked-by: Anton Blanchard <anton@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc/mm: Properly invalidate when setting process table base
The host process table base is stored in the partition table by calling
the function native_register_process_table(). Currently this just sets
the entry in memory and is missing a subsequent cache invalidation
instruction. Any update to the partition table should be followed by a
cache invalidation instruction specifying invalidation of the caching of
any partition table entries (RIC = 2, PRS = 0).
We already have a function to update the partition table with the
required cache invalidation instructions - mmu_partition_table_set_entry().
Update the native_register_process_table() function to call
mmu_partition_table_set_entry(), this ensures all appropriate
invalidation will be performed.
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
[mpe: Use a local for patb0 to clean it up slightly] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc/xive: Ensure active irqd when setting affinity
Ensure irqd is active before attempting to set affinity. This should
make the set affinity code more robust. For instance, this prevents
these messages seen on a 4.12 based kernel when taking cpus offline:
[ 123.053037264,3] XIVE[ IC 00 ] ISN 2 lead to invalid IVE !
[ 77.885859] xive: Error -6 reconfiguring irq 17
[ 77.885862] IRQ17: set affinity failed(-6).
That particular case has been fixed in 4.13-rc1 by commit 91f26cb4cd3c ("genirq/cpuhotplug: Do not migrated shutdown irqs").
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Nicholas Piggin [Tue, 1 Aug 2017 12:00:54 +0000 (22:00 +1000)]
powerpc: Add irq accounting for watchdog interrupts
This adds an irq counter for the watchdog soft-NMI. This interrupt
only fires when interrupts are soft-disabled, so it will not
increment much even when the watchdog is running. However it's
useful for debugging and sanity checking.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The powerpc kernel/watchdog.o should be built when HARDLOCKUP_DETECTOR
and HAVE_HARDLOCKUP_DETECTOR_ARCH are both selected. If only the former
is selected, then the generic perf watchdog has been selected.
To simplify this check, introduce a new Kconfig symbol PPC_WATCHDOG that
depends on both. This Kconfig option means the powerpc specific
watchdog is enabled.
Without this patch, Book3E will attempt to build the powerpc watchdog.
Fixes: 2104180a53 ("powerpc/64s: implement arch-specific hardlockup watchdog") Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Nathan Fontenot [Wed, 2 Aug 2017 18:03:22 +0000 (14:03 -0400)]
powerpc/pseries: Check memory device state before onlining/offlining
When DLPAR adding or removing memory we need to check the device
offline status before trying to online/offline the memory. This is
needed because calls to device_online() and device_offline() will
return non-zero for memory that is already online and offline
respectively.
This update resolves two scenarios. First, for a kernel built with
auto-online memory enabled (CONFIG_MEMORY_HOTPLUG_DEFAULT_ONLINE=y),
memory will be onlined as part of calls to add_memory(). After adding
the memory the pseries DLPAR code tries to online it and fails since
the memory is already online. The DLPAR code then tries to remove the
memory which produces the oops message below because the memory is not
offline.
The second scenario occurs when removing memory that is already
offline, i.e. marking memory offline (via sysfs) and then trying to
remove that memory. This doesn't work because offlining the already
offline memory does not succeed and the DLPAR code then fails the
DLPAR remove operation.
The fix for both scenarios is to check the device.offline status
before making the calls to device_online() or device_offline().
In practice these are almost all uses of r0 that should just be a
literal 0.
Signed-off-by: Andreas Schwab <schwab@linux-m68k.org>
[mpe: Mention r0 is almost always the culprit, fold in purgatory change] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
On 64-bit book3s, with the hash MMU, we currently define the kernel
virtual space (vmalloc, ioremap etc.), to be 16T in size. This is a
leftover from pre v3.7 when our user VM was also 16T.
Of that 16T we split it 50/50, with half used for PCI IO and ioremap
and the other 8T for vmalloc.
We never bothered to make it any bigger because 8T of vmalloc ought to
be enough for anybody. But it turns out that's not true, the per cpu
allocator wants large amounts of vmalloc space, not to make large
allocations, but to allow a large stride between allocations, because
we use pcpu_embed_first_chunk().
With a bit of juggling we can increase the entire kernel virtual space
to 64T. The only real complication is the check of the address in the
SLB miss handler, see the comment in the code.
Although we could continue to split virtual space 50/50 as we do now,
no one seems to be running out of PCI IO or ioremap space. So instead
keep that as 8T, and use the remaining 56T for vmalloc.
In future we should be able to increase the kernel virtual space to
512T, the code already supports that, it just needs testing on older
hardware.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
powerpc/mm/slb: Move comment next to the code it's referring to
There is a comment in slb_allocate() referring to the load of
paca->vmalloc_sllp, but it's several lines prior in the assembly.
We're about to change this code, and we want to add another comment,
so move the comment immediately prior to the instruction it's talking
about.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Although it looks like a constant, both the components are actually
variables, to allow us to have a different value between Radix and
Hash with a single kernel.
However that still requires both Radix and Hash to place the kernel IO
region at the same location relative to the start and end of the
kernel virtual region (namely 1/2 way through it), and we'd like to
change that.
So split KERN_IO_START out into its own variable, and initialise it
for Radix and Hash. In the medium term we should be able to
reconsolidate this, by doing a more involved rearrangement of the
location of the regions.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Acked-by: Balbir Singh <bsingharora@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Matt Brown [Fri, 4 Aug 2017 01:12:18 +0000 (11:12 +1000)]
powerpc/powernv: Use darn instruction for get_random_seed() on Power9
This adds powernv_get_random_darn() which utilises the darn instruction,
introduced in ISA v3.0/POWER9.
The darn instruction can potentially return an error, which is supported
by the get_random_seed() API, in normal usage if we see an error we just
return that to the caller.
However when detecting whether darn is functional at boot we try up to
10 times, before deciding that darn doesn't work and failing the
registration of get_random_seed(). That way an intermittent failure
at boot doesn't deprive the system of randomness until the next reboot.
Signed-off-by: Matt Brown <matthew.brown.dev@gmail.com>
[mpe: Move init into a function, tweak change log] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Frederic Barrat [Fri, 4 Aug 2017 09:55:14 +0000 (11:55 +0200)]
powerpc/powernv: Enable PCI peer-to-peer
P9 has support for PCI peer-to-peer, enabling a device to write in the
MMIO space of another device directly, without interrupting the CPU.
This patch adds support for it on powernv, by adding a new API to be
called by drivers. The pnv_pci_set_p2p(...) call configures an
'initiator', i.e the device which will issue the MMIO operation, and a
'target', i.e. the device on the receiving side.
P9 really only supports MMIO stores for the time being but that's
expected to change in the future, so the API allows to define both
load and store operations.
int pnv_pci_set_p2p(struct pci_dev *initiator, struct pci_dev *target,
u64 desc)
It uses a new OPAL call, as the configuration magic is done on the
PHBs by skiboot.
Signed-off-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Reviewed-by: Russell Currey <ruscur@russell.cc>
[mpe: Drop unrelated OPAL calls, s/uint64_t/u64/, minor formatting] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc: Remove old unused icswx based coprocessor support
We have a whole pile of unused code to maintain the ACOP register,
allocate coprocessor PIDs and handle ACOP faults. This mechanism
was used for the HFI adapter on POWER7 which is dead and gone and
whose driver never went upstream. It was used on some A2 core based
stuff that also never saw the light of day.
Take out all that code.
There is still some POWER8 coprocessor code that uses icswx but it's
kernel only and thus doesn't use any of that infrastructure.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
When hitting below a VM_GROWSDOWN vma (typically growing the stack),
we check whether it's a valid stack-growing instruction and we
check the distance to GPR1. This is largely open coded with lots
of comments, so move it out to a helper.
While at it, make store_update_sp a boolean.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Move out the code that sets FAULT_FLAG_WRITE so the block that check
access permissions can be extracted. While at it also set
FAULT_FLAG_INSTRUCTION which will be used for protection keys.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This has a page of comment explaining what's going on right in
the middle of do_page_fault() which makes things a bit hard to
follow. Move it to a helper instead. Also do the test earlier
as there's no point waiting until after we found the VMA.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
First, handle the normal retry failure in do_page_fault itself,
since it's a simple return statement. That allows us to remove
the "continue" special return code from mm_fault_error().
Once that's done, we can have an implementation much closer to
x86 where we only call mm_fault_error() if VM_FAULT_ERROR is set
and directly return.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Instead of goto labels, instead call those functions and return.
This gets us closer to x86 and allows us to shring do_page_fault()
even more.
The main difference with x86 is that those function return a value
which we then return from do_page_fault(). That value is our
return value from do_page_fault() which we use to generate
kernel faults.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc/mm: Fix reporting of kernel execute faults
We currently test for is_exec and DSISR_PROTFAULT but that doesn't
make sense as this is the wrong error bit to test for an execute
permission failure.
In fact, we had code that would return early if we had an exec
fault in kernel mode so I think that was just dead code anyway.
Finally the location of that test is awkward and prevents further
simplifications.
So instead move that test into a helper along with the existing
early test for kernel exec faults and out of range accesses,
and put it all in a "bad_kernel_fault()" helper. While at it
test the correct error bits.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
A bad page fault is when the HW signals an error such as a bad
copy/paste, an AMO error, or some other type of error that will
not be fixed by updating the PTE.
Use a helper page_fault_is_bad() to check for bad page faults thus
removing the per-processor family open-coding in __do_page_fault()
and trigger a SIGBUS rather than a SIGSEGV which is more appropriate.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc/mm: Use symbolic constants for filtering SRR1 bits on ISIs
This uses the newly defined constants for this rather than open-coded
numbers. There is a side effect on 64-bit which is to pass through
some of the new P9 bits which we didn't before.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
We test a number of bits from DSISR/SRR1 before deciding
to call hash_page(). If any of these is set, we go directly
to do_page_fault() as the bit indicate a fault that needs
to be handled there (no hashing needed).
This updates the current open-coded masks to use the new
DSISR definitions.
This *does* change the masks actually used in two ways:
- We used to test various bits that were defined as "always 0"
in the architecture and could be repurposed for something
else. From now on, we just ignore such bits.
- We were missing some new bits defined on P9
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This updates the definitions for the various DSISR bits to
match both some historical stuff and to match new bits on
POWER9.
In addition, we define some masks corresponding to the "bad"
faults on Book3S, and some masks corresponding to the bits
that match between DSISR and SRR1 for a DSI and an ISI.
This comes with a small code update to change the definition
of DSISR_PGDIRFAULT which becomes DSISR_PRTABLE_FAULT to
match architecture 3.0B
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc/6xx: Handle DABR match before calling do_page_fault
On legacy 6xx 32-bit procesors, we checked for the DABR match bit
in DSISR from do_page_fault(), in the middle of a pile of ifdef's
because all other CPU types do it in assembly prior to calling
do_page_fault. Fix that.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
[mpe: Add #ifdef CONFIG_6xx] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
projects / kernel.git / log