IDE subsystem has been deprecated since 2009 and the majority
(if not all) of Linux distributions have switched to use
libata for ATA support exclusively. However there are still
some users (mostly old or/and embedded non-x86 systems) that
have not converted from using IDE subsystem to libata PATA
drivers. This doesn't seem to be good thing in the long-term
for Linux as while there is less and less PATA systems left
in use:
* testing efforts are divided between two subsystems
* having duplicate drivers for same hardware confuses users
This patch converts amigaone_defconfig to use libata PATA
drivers.
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Add comment clarifying that vio_find_node() takes a reference to the
embedded struct device which needs to be dropped after use.
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Make sure to drop any reference taken by bus_find_device() when creating
devices during init and driver registration.
Fixes: 55347cc996 ("[POWERPC] ibmebus: Add device creation and bus probing based on of_device")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Make sure to drop any reference taken by bus_find_device() in the sysfs
callbacks that are used to create and destroy devices based on
device-tree entries.
Fixes: 6bccf755ff ("[POWERPC] ibmebus: dynamic addition/removal of adapters, some code cleanup")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This condenses the opal node searching into a single function that finds
all compatible nodes, instead of just searching the ibm,opal children,
for ipmi, flash, and prd similar to how opal-i2c nodes are found.
Signed-off-by: Jack Miller <jack@codezen.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Load monitored is no longer supported on POWER9 so let's remove the
code.
This reverts commit bd3ea317fd ("powerpc: Load Monitor Register
Support").
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
No one uses reiserfs much these days, or is likely to in future. So drop
it from pseries and powernv defconfigs to save time and space. It's
still enabled in ppc64_defconfig so we get some build coverage.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
In ISA v2.05, the tlbiel instruction takes two arguments, RB and L:
tlbiel RB,L
+---------+---------+----+---------+---------+---------+----+
| 31 | / | L | / | RB | 274 | / |
| 31 - 26 | 25 - 22 | 21 | 20 - 16 | 15 - 11 | 10 - 1 | 0 |
+---------+---------+----+---------+---------+---------+----+
In ISA v2.06 tlbiel takes only one argument, RB:
tlbiel RB
+---------+---------+---------+---------+---------+----+
| 31 | / | / | RB | 274 | / |
| 31 - 26 | 25 - 21 | 20 - 16 | 15 - 11 | 10 - 1 | 0 |
+---------+---------+---------+---------+---------+----+
And in ISA v3.00 tlbiel takes five arguments:
tlbiel RB,RS,RIC,PRS,R
+---------+---------+----+---------+----+----+---------+---------+----+
| 31 | RS | / | RIC |PRS | R | RB | 274 | / |
| 31 - 26 | 25 - 21 | 20 | 19 - 18 | 17 | 16 | 15 - 11 | 10 - 1 | 0 |
+---------+---------+----+---------+----+----+---------+---------+----+
However the assembler also accepts "tlbiel RB", and generates
"tlbiel RB,r0,0,0,0".
As you can see above the L field from the v2.05 encoding overlaps with the
reserved field of the v2.06 encoding, and the low bit of the RS field of the
v3.00 encoding.
Currently in __tlbiel() we generate two tlbiel instructions manually using hex
constants. In the first case, for MMU_PAGE_4K, we generate "tlbiel RB,0", which
is safe in all cases, because the L bit is zero.
However in the default case we generate "tlbiel RB,1", therefore setting bit 21
to 1.
This is not an actual bug on v2.06 processors, because the CPU ignores the value
of the reserved field. However software is supposed to encode the reserved
fields as zero to enable forward compatibility.
On v3.00 processors setting bit 21 to 1 and no other bits of RS, means we are
using r1 for the value of RS.
Although it's not obvious, the code sets the IS field (bits 10-11) to 0 (by
omission), and L=1, in the va value, which is passed as RB. We also pass R=0 in
the instruction.
The combination of IS=0, L=1 and R=0 means the value of RS is not used, so even
on ISA v3.00 there is no actual bug.
We should still fix it, as setting a reserved bit on v2.06 is naughty, and we
are only avoiding a bug on v3.00 by accident rather than design. Use
ASM_FTR_IFSET() to generate the single argument form on ISA v2.06 and later, and
the two argument form on pre v2.06.
Although there may be very old toolchains which don't understand tlbiel, we have
other code in the tree which has been using tlbiel for over five years, and no
one has reported any build failures, so just let the assembler generate the
instructions.
Signed-off-by: Balbir Singh <bsingharora@gmail.com>
[mpe: Rewrite change log, use IFSET instead of IFCLR]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
When we're not compiling for a specific CPU, ie. none of the
CONFIG_POWERx_CPU options are set, and CONFIG_GENERIC_CPU *is* set, we
currently don't pass any -mcpu option to the compiler. This means the
compiler builds for a "generic" Power CPU.
But back in 2014 we dropped support for pre power4 CPUs in commit
468a33028e ("powerpc: Drop support for pre-POWER4 cpus").
Given that, there's no point in building the kernel to run on pre power4
cpus. So update the flags we pass to the compiler when
CONFIG_GENERIC_CPU is set, to specify -mcpu=power4.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This adds a config option that can help exercise the case when
the kernel is not running at PAGE_OFFSET.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
An hcall was recently added that does exactly what we need during kexec
- it clears the entire MMU hash table, ignoring any VRMA mappings.
Try it and fall back to the old method if we get a failure.
On a POWER8 box with 5TB of memory, this reduces the time it takes to
kexec a new kernel from from 4 minutes to 1 minute.
Signed-off-by: Anton Blanchard <anton@samba.org>
Tested-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
[mpe: Split into separate functions and tweak function naming]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This halves the exception table size on 64-bit builds, and it allows
build-time sorting of exception tables to work on relocated kernels.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Minor asm fixups and bits to keep the selftests working]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This macro is taken from s390, and allows more flexibility in
changing exception table format.
mpe: Put it in ppc_asm.h and only define one version using
stringinfy_in_c(). Add some empty definitions and headers to keep the
selftests happy.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
We haven't seen these before, but the soon to be merged relative
exception tables support causes them to be generated.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
There's no reason to #error if we include ppc_asm.h in asm files, the
ifdef already prevents any problems.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Exception handlers are aligned to 128 bytes (L1 cache) on 64s, which is
overkill. It can reduce the icache footprint of any individual exception
path. However taken as a whole, the expansion in icache footprint seems
likely to be counter-productive and cause more total misses.
Create IFETCH_ALIGN_SHIFT/BYTES, which should give optimal ifetch
alignment with much more reasonable alignment. This saves 1792 bytes
from head_64.o text with an allmodconfig build.
Other subarchitectures should define appropriate IFETCH_ALIGN_SHIFT
values if this becomes more widely used.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
There are three #ifdef CONFIG_PPC_BOOK3E sections in nohash/64/pgtable.h.
And there should be no configurations possible which use nohash/64/pgtable.h
but don't also enable CONFIG_PPC_BOOK3E.
Suggested-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Rui Teng <rui.teng@linux.vnet.ibm.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Since the KERN_CONT changes, the current code in show_instructions()
prints out a whole bunch of unnecessary newlines. Change occurrences of
printk("\n") to pr_cont("\n"). While we're here, change all the other
cases of printk(KERN_CONT ...) to pr_cont() as well.
Signed-off-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Fix up our oops output by converting continuation lines to use
pr_cont(). Some of these are dubious, eg. printing a continuation line
which starts with a newline, but seem to work OK for now. This whole
function needs a rewrite in the next release.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Since the KERN_CONT changes these are being horribly split across lines,
for example:
MSR: 8000000000009033 <
SF,EE
,ME,IR
,DR,RI
,LE>
So fix it by using pr_cont() where appropriate.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Previously we got away with printing the stack trace in multiple pieces
and it usually looked right. But since commit 4bcc595ccd ("printk:
reinstate KERN_CONT for printing continuation lines"), KERN_CONT is now
required when printing continuation lines. Use pr_cont() as appropriate.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The changes to use gas sections for constructing the exception vectors
causes a build break when using binutils 2.23:
arch/powerpc/kernel/exceptions-64s.S:770: Error: operand out of range
(0xffffffffffff8100 is not between 0x0000000000000000 and 0x000000000000ffff)
And so on.
Reported by Hugh with binutils-2.23.2-8.1.4.ppc64 from openSUSE 13.1 and
also Naveen & Denis using 2.23.52.0.1-26.el7 from RHEL 7. Strangely
binutils 2.22 (what I test with) is not affected.
This is caused by the use of @l in LOAD_HANDLER(). The @l was only
recently added in commit a24553dd02 ("powerpc/pseries: Remove
unnecessary syscall trampoline").
Luckily the gas section changes split out the LOAD_SYSCALL_HANDLER()
macro, which means we actually *don't* need to use @l in LOAD_HANDLER()
any more, only in LOAD_SYSCALL_HANDLER().
So drop the @l from LOAD_HANDLER().
Fixes: 57f266497d ("powerpc: Use gas sections for arranging exception vectors")
Signed-off-by: Hugh Dickins <hughd@google.com>
[mpe: Add gory details to change log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Wakeups from winkle set the low bit of the HSPRG0 register, to
distinguish it from other sleep states. This is also the PACA pointer.
The system reset exception handler fails to mask this bit away before
using this value before using it as the PACA pointer.
Fix this by adding a new type of exception prolog macro where we already
have the PACA set in r13, and have the system reset vector mask it out.
The winkle wakeup handler will store the masked value back into HSPRG0.
Fixes: fb479e44a9 ("powerpc/64s: relocation, register save fixes for system reset interrupt")
Cc: stable@vger.kernel.org # v3.0+
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Pull networking fixes from David Miller:
"Lots of fixes, mostly drivers as is usually the case.
1) Don't treat zero DMA address as invalid in vmxnet3, from Alexey
Khoroshilov.
2) Fix element timeouts in netfilter's nft_dynset, from Anders K.
Pedersen.
3) Don't put aead_req crypto struct on the stack in mac80211, from
Ard Biesheuvel.
4) Several uninitialized variable warning fixes from Arnd Bergmann.
5) Fix memory leak in cxgb4, from Colin Ian King.
6) Fix bpf handling of VLAN header push/pop, from Daniel Borkmann.
7) Several VRF semantic fixes from David Ahern.
8) Set skb->protocol properly in ip6_tnl_xmit(), from Eli Cooper.
9) Socket needs to be locked in udp_disconnect(), from Eric Dumazet.
10) Div-by-zero on 32-bit fix in mlx4 driver, from Eugenia Emantayev.
11) Fix stale link state during failover in NCSCI driver, from Gavin
Shan.
12) Fix netdev lower adjacency list traversal, from Ido Schimmel.
13) Propvide proper handle when emitting notifications of filter
deletes, from Jamal Hadi Salim.
14) Memory leaks and big-endian issues in rtl8xxxu, from Jes Sorensen.
15) Fix DESYNC_FACTOR handling in ipv6, from Jiri Bohac.
16) Several routing offload fixes in mlxsw driver, from Jiri Pirko.
17) Fix broadcast sync problem in TIPC, from Jon Paul Maloy.
18) Validate chunk len before using it in SCTP, from Marcelo Ricardo
Leitner.
19) Revert a netns locking change that causes regressions, from Paul
Moore.
20) Add recursion limit to GRO handling, from Sabrina Dubroca.
21) GFP_KERNEL in irq context fix in ibmvnic, from Thomas Falcon.
22) Avoid accessing stale vxlan/geneve socket in data path, from
Pravin Shelar"
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (189 commits)
geneve: avoid using stale geneve socket.
vxlan: avoid using stale vxlan socket.
qede: Fix out-of-bound fastpath memory access
net: phy: dp83848: add dp83822 PHY support
enic: fix rq disable
tipc: fix broadcast link synchronization problem
ibmvnic: Fix missing brackets in init_sub_crq_irqs
ibmvnic: Fix releasing of sub-CRQ IRQs in interrupt context
Revert "ibmvnic: Fix releasing of sub-CRQ IRQs in interrupt context"
arch/powerpc: Update parameters for csum_tcpudp_magic & csum_tcpudp_nofold
net/mlx4_en: Save slave ethtool stats command
net/mlx4_en: Fix potential deadlock in port statistics flow
net/mlx4: Fix firmware command timeout during interrupt test
net/mlx4_core: Do not access comm channel if it has not yet been initialized
net/mlx4_en: Fix panic during reboot
net/mlx4_en: Process all completions in RX rings after port goes up
net/mlx4_en: Resolve dividing by zero in 32-bit system
net/mlx4_core: Change the default value of enable_qos
net/mlx4_core: Avoid setting ports to auto when only one port type is supported
net/mlx4_core: Fix the resource-type enum in res tracker to conform to FW spec
...
Commit 01cfbad "ipv4: Update parameters for csum_tcpudp_magic to their
original types" changed parameters for csum_tcpudp_magic and
csum_tcpudp_nofold for many platforms but not for PowerPC.
Fixes: 01cfbad "ipv4: Update parameters for csum_tcpudp_magic to their original types"
Cc: Alexander Duyck <aduyck@mirantis.com>
Signed-off-by: Ivan Vecera <ivecera@redhat.com>
Acked-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull powerpc fixes from Michael Ellerman:
"Fixes marked for stable:
- Convert cmp to cmpd in idle enter sequence (Segher Boessenkool)
- cxl: Fix leaking pid refs in some error paths (Vaibhav Jain)
- Re-fix race condition between going idle and entering guest (Paul Mackerras)
- Fix race condition in setting lock bit in idle/wakeup code (Paul Mackerras)
- radix: Use tlbiel only if we ever ran on the current cpu (Aneesh Kumar K.V)
- relocation, register save fixes for system reset interrupt (Nicholas Piggin)
Fixes for code merged this cycle:
- Fix CONFIG_ALIVEC typo in restore_tm_state() (Valentin Rothberg)
- KVM: PPC: Book3S HV: Fix build error when SMP=n (Michael Ellerman)"
* tag 'powerpc-4.9-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/64s: relocation, register save fixes for system reset interrupt
powerpc/mm/radix: Use tlbiel only if we ever ran on the current cpu
powerpc/process: Fix CONFIG_ALIVEC typo in restore_tm_state()
powerpc/64: Fix race condition in setting lock bit in idle/wakeup code
powerpc/64: Re-fix race condition between going idle and entering guest
cxl: Fix leaking pid refs in some error paths
powerpc: Convert cmp to cmpd in idle enter sequence
KVM: PPC: Book3S HV: Fix build error when SMP=n
Pull perf fixes from Ingo Molnar:
"Misc kernel fixes: a virtualization environment related fix, an uncore
PMU driver removal handling fix, a PowerPC fix and new events for
Knights Landing"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/intel: Honour the CPUID for number of fixed counters in hypervisors
perf/powerpc: Don't call perf_event_disable() from atomic context
perf/core: Protect PMU device removal with a 'pmu_bus_running' check, to fix CONFIG_DEBUG_TEST_DRIVER_REMOVE=y kernel panic
perf/x86/intel/cstate: Add C-state residency events for Knights Landing
The trinity syscall fuzzer triggered following WARN() on powerpc:
WARNING: CPU: 9 PID: 2998 at arch/powerpc/kernel/hw_breakpoint.c:278
...
NIP [c00000000093aedc] .hw_breakpoint_handler+0x28c/0x2b0
LR [c00000000093aed8] .hw_breakpoint_handler+0x288/0x2b0
Call Trace:
[c0000002f7933580] [c00000000093aed8] .hw_breakpoint_handler+0x288/0x2b0 (unreliable)
[c0000002f7933630] [c0000000000f671c] .notifier_call_chain+0x7c/0xf0
[c0000002f79336d0] [c0000000000f6abc] .__atomic_notifier_call_chain+0xbc/0x1c0
[c0000002f7933780] [c0000000000f6c40] .notify_die+0x70/0xd0
[c0000002f7933820] [c00000000001a74c] .do_break+0x4c/0x100
[c0000002f7933920] [c0000000000089fc] handle_dabr_fault+0x14/0x48
Followed by a lockdep warning:
===============================
[ INFO: suspicious RCU usage. ]
4.8.0-rc5+ #7 Tainted: G W
-------------------------------
./include/linux/rcupdate.h:556 Illegal context switch in RCU read-side critical section!
other info that might help us debug this:
rcu_scheduler_active = 1, debug_locks = 0
2 locks held by ls/2998:
#0: (rcu_read_lock){......}, at: [<c0000000000f6a00>] .__atomic_notifier_call_chain+0x0/0x1c0
#1: (rcu_read_lock){......}, at: [<c00000000093ac50>] .hw_breakpoint_handler+0x0/0x2b0
stack backtrace:
CPU: 9 PID: 2998 Comm: ls Tainted: G W 4.8.0-rc5+ #7
Call Trace:
[c0000002f7933150] [c00000000094b1f8] .dump_stack+0xe0/0x14c (unreliable)
[c0000002f79331e0] [c00000000013c468] .lockdep_rcu_suspicious+0x138/0x180
[c0000002f7933270] [c0000000001005d8] .___might_sleep+0x278/0x2e0
[c0000002f7933300] [c000000000935584] .mutex_lock_nested+0x64/0x5a0
[c0000002f7933410] [c00000000023084c] .perf_event_ctx_lock_nested+0x16c/0x380
[c0000002f7933500] [c000000000230a80] .perf_event_disable+0x20/0x60
[c0000002f7933580] [c00000000093aeec] .hw_breakpoint_handler+0x29c/0x2b0
[c0000002f7933630] [c0000000000f671c] .notifier_call_chain+0x7c/0xf0
[c0000002f79336d0] [c0000000000f6abc] .__atomic_notifier_call_chain+0xbc/0x1c0
[c0000002f7933780] [c0000000000f6c40] .notify_die+0x70/0xd0
[c0000002f7933820] [c00000000001a74c] .do_break+0x4c/0x100
[c0000002f7933920] [c0000000000089fc] handle_dabr_fault+0x14/0x48
While it looks like the first WARN() is probably valid, the other one is
triggered by disabling event via perf_event_disable() from atomic context.
The event is disabled here in case we were not able to emulate
the instruction that hit the breakpoint. By disabling the event
we unschedule the event and make sure it's not scheduled back.
But we can't call perf_event_disable() from atomic context, instead
we need to use the event's pending_disable irq_work method to disable it.
Reported-by: Jan Stancek <jstancek@redhat.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Neuling <mikey@neuling.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20161026094824.GA21397@krava
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This patch does a couple of things. First of all, powernv immediately
explodes when running a relocated kernel, because the system reset
exception for handling sleeps does not do correct relocated branches.
Secondly, the sleep handling code trashes the condition and cfar
registers, which we would like to preserve for debugging purposes (for
non-sleep case exception).
This patch changes the exception to use the standard format that saves
registers before any tests or branches are made. It adds the test for
idle-wakeup as an "extra" to break out of the normal exception path.
Then it branches to a relocated idle handler that calls the various
idle handling functions.
After this patch, POWER8 CPU simulator now boots powernv kernel that is
running at non-zero.
Fixes: 948cf67c47 ("powerpc: Add NAP mode support on Power7 in HV mode")
Cc: stable@vger.kernel.org # v3.0+
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Acked-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Before this patch, we used tlbiel, if we ever ran only on this core.
That was mostly derived from the nohash usage of the same. But is
incorrect, the ISA 3.0 clarifies tlbiel such that:
"All TLB entries that have all of the following properties are made
invalid on the thread executing the tlbiel instruction"
ie. tlbiel only invalidates TLB entries on the current thread. So if the
mm has been used on any other thread (aka. cpu) then we must broadcast
the invalidate.
This bug could lead to invalid TLB entries if a program runs on multiple
threads of a core.
Hence use tlbiel, if we only ever ran on only the current cpu.
Fixes: 1a472c9dba ("powerpc/mm/radix: Add tlbflush routines")
Cc: stable@vger.kernel.org # v4.7+
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
It should be ALTIVEC, not ALIVEC.
Cyril explains: If a thread performs a transaction with altivec and then
gets preempted for whatever reason, this bug may cause the kernel to not
re-enable altivec when that thread runs again. This will result in an
altivec unavailable fault, when that fault happens inside a user
transaction the kernel has no choice but to enable altivec and doom the
transaction.
The result is that transactions using altivec may get aborted more often
than they should.
The difficulty in catching this with a selftest is my deliberate use of
the word may above. Optimisations to avoid FPU/altivec/VSX faults mean
that the kernel will always leave them on for 255 switches. This code
prevents the kernel turning it off if it got to the 256th switch (and
userspace was transactional).
Fixes: dc16b553c9 ("powerpc: Always restore FPU/VEC/VSX if hardware transactional memory in use")
Reviewed-by: Cyril Bur <cyrilbur@gmail.com>
Signed-off-by: Valentin Rothberg <valentinrothberg@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This fixes a race condition where one thread that is entering or
leaving a power-saving state can inadvertently ignore the lock bit
that was set by another thread, and potentially also clear it.
The core_idle_lock_held function is called when the lock bit is
seen to be set. It polls the lock bit until it is clear, then
does a lwarx to load the word containing the lock bit and thread
idle bits so it can be updated. However, it is possible that the
value loaded with the lwarx has the lock bit set, even though an
immediately preceding lwz loaded a value with the lock bit clear.
If this happens then we go ahead and update the word despite the
lock bit being set, and when called from pnv_enter_arch207_idle_mode,
we will subsequently clear the lock bit.
No identifiable misbehaviour has been attributed to this race.
This fixes it by checking the lock bit in the value loaded by the
lwarx. If it is set then we just go back and keep on polling.
Fixes: b32aadc1a8 ("powerpc/powernv: Fix race in updating core_idle_state")
Cc: stable@vger.kernel.org # v4.2+
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Commit 8117ac6a6c ("powerpc/powernv: Switch off MMU before entering
nap/sleep/rvwinkle mode", 2014-12-10) fixed a race condition where one
thread entering a KVM guest could switch the MMU context to the guest
while another thread was still in host kernel context with the MMU on.
That commit moved the point where a thread entering a power-saving
mode set its kvm_hstate.hwthread_state field in its PACA to
KVM_HWTHREAD_IN_IDLE from a point where the MMU was on to after the
MMU had been switched off. That commit also added a comment
explaining that we have to switch to real mode before setting
hwthread_state to avoid this race.
Nevertheless, commit 4eae2c9ae5 ("powerpc/powernv: Make
pnv_powersave_common more generic", 2016-07-08) subsequently moved
the setting of hwthread_state back to a point where the MMU is on,
thus reintroducing the race, despite the comment saying that this
should not be done being included in full in the context lines of
the patch that did it.
This fixes the race again and adds a bigger and shoutier comment
explaining the potential race condition.
Fixes: 4eae2c9ae5 ("powerpc/powernv: Make pnv_powersave_common more generic")
Cc: stable@vger.kernel.org # v4.8+
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Reviewed-by: Shreyas B. Prabhu <shreyasbp@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Pull powerpc fixes from Michael Ellerman:
"Fixes marked for stable:
- Prevent unlikely crash in copro_calculate_slb() (Frederic Barrat)
- cxl: Prevent adapter reset if an active context exists (Vaibhav Jain)
Fixes for code merged this cycle:
- Fix boot on systems with uncompressed kernel image (Heiner Kallweit)
- Drop dump_numa_memory_topology() (Michael Ellerman)
- Fix numa topology console print (Aneesh Kumar K.V)
- Ignore the pkey system calls for now (Stephen Rothwell)"
* tag 'powerpc-4.9-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc: Ignore the pkey system calls for now
powerpc: Fix numa topology console print
powerpc/mm: Drop dump_numa_memory_topology()
cxl: Prevent adapter reset if an active context exists
powerpc/boot: Fix boot on systems with uncompressed kernel image
powerpc/mm: Prevent unlikely crash in copro_calculate_slb()
PowerPC's "cmp" instruction has four operands. Normally people write
"cmpw" or "cmpd" for the second cmp operand 0 or 1. But, frequently
people forget, and write "cmp" with just three operands.
With older binutils this is silently accepted as if this was "cmpw",
while often "cmpd" is wanted. With newer binutils GAS will complain
about this for 64-bit code. For 32-bit code it still silently assumes
"cmpw" is what is meant.
In this instance the code comes directly from ISA v2.07, including the
cmp, but cmpd is correct. Backport to stable so that new toolchains can
build old kernels.
Fixes: 948cf67c47 ("powerpc: Add NAP mode support on Power7 in HV mode")
Cc: stable@vger.kernel.org # v3.0
Reviewed-by: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Signed-off-by: Segher Boessenkool <segher@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Commit 5d375199ea ("KVM: PPC: Book3S HV: Set server for passed-through
interrupts") broke the SMP=n build:
arch/powerpc/kvm/book3s_hv_rm_xics.c:758:2: error: implicit declaration of function 'get_hard_smp_processor_id'
That is because we lost the implicit include of asm/smp.h, so include it
explicitly to get the definition for get_hard_smp_processor_id().
Fixes: 5d375199ea ("KVM: PPC: Book3S HV: Set server for passed-through interrupts")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Merge the gup_flags cleanups from Lorenzo Stoakes:
"This patch series adjusts functions in the get_user_pages* family such
that desired FOLL_* flags are passed as an argument rather than
implied by flags.
The purpose of this change is to make the use of FOLL_FORCE explicit
so it is easier to grep for and clearer to callers that this flag is
being used. The use of FOLL_FORCE is an issue as it overrides missing
VM_READ/VM_WRITE flags for the VMA whose pages we are reading
from/writing to, which can result in surprising behaviour.
The patch series came out of the discussion around commit 38e0885465
("mm: check VMA flags to avoid invalid PROT_NONE NUMA balancing"),
which addressed a BUG_ON() being triggered when a page was faulted in
with PROT_NONE set but having been overridden by FOLL_FORCE.
do_numa_page() was run on the assumption the page _must_ be one marked
for NUMA node migration as an actual PROT_NONE page would have been
dealt with prior to this code path, however FOLL_FORCE introduced a
situation where this assumption did not hold.
See
https://marc.info/?l=linux-mm&m=147585445805166
for the patch proposal"
Additionally, there's a fix for an ancient bug related to FOLL_FORCE and
FOLL_WRITE by me.
[ This branch was rebased recently to add a few more acked-by's and
reviewed-by's ]
* gup_flag-cleanups:
mm: replace access_process_vm() write parameter with gup_flags
mm: replace access_remote_vm() write parameter with gup_flags
mm: replace __access_remote_vm() write parameter with gup_flags
mm: replace get_user_pages_remote() write/force parameters with gup_flags
mm: replace get_user_pages() write/force parameters with gup_flags
mm: replace get_vaddr_frames() write/force parameters with gup_flags
mm: replace get_user_pages_locked() write/force parameters with gup_flags
mm: replace get_user_pages_unlocked() write/force parameters with gup_flags
mm: remove write/force parameters from __get_user_pages_unlocked()
mm: remove write/force parameters from __get_user_pages_locked()
mm: remove gup_flags FOLL_WRITE games from __get_user_pages()
This removes the 'write' argument from access_process_vm() and replaces
it with 'gup_flags' as use of this function previously silently implied
FOLL_FORCE, whereas after this patch callers explicitly pass this flag.
We make this explicit as use of FOLL_FORCE can result in surprising
behaviour (and hence bugs) within the mm subsystem.
Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Eliminates warning messages:
<stdin>:1316:2: warning: #warning syscall pkey_mprotect not implemented [-Wcpp]
<stdin>:1319:2: warning: #warning syscall pkey_alloc not implemented [-Wcpp]
<stdin>:1322:2: warning: #warning syscall pkey_free not implemented [-Wcpp]
Hopefully we will remember to revert this commit if we ever implement
them.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
At boot we dump the NUMA memory topology in dump_numa_memory_topology(),
at KERN_DEBUG level, resulting in output like:
Node 0 Memory: 0x0-0x100000000
Node 1 Memory: 0x100000000-0x200000000
Which is nice enough, but immediately after that we iterate over each
node and call setup_node_data(), which also prints out the node ranges,
at KERN_INFO, giving eg:
numa: Initmem setup node 0 [mem 0x00000000-0xffffffff]
numa: Initmem setup node 1 [mem 0x100000000-0x1ffffffff]
Additionally dump_numa_memory_topology() does not use KERN_CONT
correctly, resulting in split output lines on recent kernels.
So drop dump_numa_memory_topology() as superfluous chatter.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This commit broke boot on systems with an uncompressed kernel image,
namely systems using a cuImage. On such systems the compressed boot
image (boot wrapper, uncompressed kernel image, ..) is decompressed
by u-boot already, therefore the boot wrapper code sees an
uncompressed kernel image.
The old decompression code silently assumed an uncompressed kernel
image if it found no valid gzip signature, whilst the new code
bailed out in this case.
Fix this by re-introducing such a fallback if no valid compressed
image is found.
Fixes: 1b7898ee27 ("Use the pre-boot decompression API")
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
If a cxl adapter faults on an invalid address for a kernel context, we
may enter copro_calculate_slb() with a NULL mm pointer (kernel
context) and an effective address which looks like a user
address. Which will cause a crash when dereferencing mm. It is clearly
an AFU bug, but there's no reason to crash either. So return an error,
so that cxl can ack the interrupt with an address error.
Fixes: 73d16a6e0e ("powerpc/cell: Move data segment faulting code out of cell platform")
Cc: stable@vger.kernel.org # v3.18+
Signed-off-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Acked-by: Ian Munsie <imunsie@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Pull gcc plugins update from Kees Cook:
"This adds a new gcc plugin named "latent_entropy". It is designed to
extract as much possible uncertainty from a running system at boot
time as possible, hoping to capitalize on any possible variation in
CPU operation (due to runtime data differences, hardware differences,
SMP ordering, thermal timing variation, cache behavior, etc).
At the very least, this plugin is a much more comprehensive example
for how to manipulate kernel code using the gcc plugin internals"
* tag 'gcc-plugins-v4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
latent_entropy: Mark functions with __latent_entropy
gcc-plugins: Add latent_entropy plugin
Pull kbuild updates from Michal Marek:
- EXPORT_SYMBOL for asm source by Al Viro.
This does bring a regression, because genksyms no longer generates
checksums for these symbols (CONFIG_MODVERSIONS). Nick Piggin is
working on a patch to fix this.
Plus, we are talking about functions like strcpy(), which rarely
change prototypes.
- Fixes for PPC fallout of the above by Stephen Rothwell and Nick
Piggin
- fixdep speedup by Alexey Dobriyan.
- preparatory work by Nick Piggin to allow architectures to build with
-ffunction-sections, -fdata-sections and --gc-sections
- CONFIG_THIN_ARCHIVES support by Stephen Rothwell
- fix for filenames with colons in the initramfs source by me.
* 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild: (22 commits)
initramfs: Escape colons in depfile
ppc: there is no clear_pages to export
powerpc/64: whitelist unresolved modversions CRCs
kbuild: -ffunction-sections fix for archs with conflicting sections
kbuild: add arch specific post-link Makefile
kbuild: allow archs to select link dead code/data elimination
kbuild: allow architectures to use thin archives instead of ld -r
kbuild: Regenerate genksyms lexer
kbuild: genksyms fix for typeof handling
fixdep: faster CONFIG_ search
ia64: move exports to definitions
sparc32: debride memcpy.S a bit
[sparc] unify 32bit and 64bit string.h
sparc: move exports to definitions
ppc: move exports to definitions
arm: move exports to definitions
s390: move exports to definitions
m68k: move exports to definitions
alpha: move exports to actual definitions
x86: move exports to actual definitions
...
