The first is a fix for the way the ring buffer stores timestamps.
After a restructure of the code was done, the ring buffer timestamp
logic missed the fact that the first event on a sub buffer is to have
a zero delta, as the full timestamp is stored on the sub buffer itself.
But because the delta was not cleared to zero, the timestamp for that
event will be calculated as the real timestamp + the delta from the
last timestamp. This can skew the timestamps of the events and
have them say they happened when they didn't really happen. That's bad.
The second fix is for modifying the function graph caller site.
When the stop machine was removed from updating the function tracing
code, it missed updating the function graph call site location.
It is still modified as if it is being done via stop machine. But it's not.
This can lead to a GPF and kernel crash if the function graph call site
happens to lie between cache lines and one CPU is executing it while
another CPU is doing the update. It would be a very hard condition to
hit, but the result is sever enough to have it fixed ASAP.
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Merge tag 'trace-fixes-v3.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull twi tracing fixes from Steven Rostedt:
"Two urgent fixes in the tracing utility.
The first is a fix for the way the ring buffer stores timestamps.
After a restructure of the code was done, the ring buffer timestamp
logic missed the fact that the first event on a sub buffer is to have
a zero delta, as the full timestamp is stored on the sub buffer
itself. But because the delta was not cleared to zero, the timestamp
for that event will be calculated as the real timestamp + the delta
from the last timestamp. This can skew the timestamps of the events
and have them say they happened when they didn't really happen.
That's bad.
The second fix is for modifying the function graph caller site. When
the stop machine was removed from updating the function tracing code,
it missed updating the function graph call site location. It is still
modified as if it is being done via stop machine. But it's not. This
can lead to a GPF and kernel crash if the function graph call site
happens to lie between cache lines and one CPU is executing it while
another CPU is doing the update. It would be a very hard condition to
hit, but the result is severe enough to have it fixed ASAP"
* tag 'trace-fixes-v3.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
ftrace/x86: Use breakpoints for converting function graph caller
ring-buffer: Fix first commit on sub-buffer having non-zero delta
Pull x86 EFI fixes from Peter Anvin:
"A few more EFI-related fixes"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/efi: Check status field to validate BGRT header
x86/efi: Fix 32-bit fallout
Mostly a collection of Kconfig, device tree data and compilation fixes
along with fix to drivers/phy that fixes a boot regression on some
Marvell mvebu platforms.
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Merge tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM SoC fixes from Kevin Hilman:
"A collection of ARM SoC fixes for v3.14-rc1.
Mostly a collection of Kconfig, device tree data and compilation fixes
along with fix to drivers/phy that fixes a boot regression on some
Marvell mvebu platforms"
* tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
dma: mv_xor: Silence a bunch of LPAE-related warnings
ARM: ux500: disable msp2 device tree node
ARM: zynq: Reserve not DMAable space in front of the kernel
ARM: multi_v7_defconfig: Select CONFIG_SOC_DRA7XX
ARM: imx6: Initialize low-power mode early again
ARM: pxa: fix various compilation problems
ARM: pxa: fix compilation problem on AM300EPD board
ARM: at91: add Atmel's SAMA5D3 Xplained board
spi/atmel: document clock properties
mmc: atmel-mci: document clock properties
ARM: at91: enable USB host on at91sam9n12ek board
ARM: at91/dt: fix sama5d3 ohci hclk clock reference
ARM: at91/dt: sam9263: fix compatibility string for the I2C
ata: sata_mv: Fix probe failures with optional phys
drivers: phy: Add support for optional phys
drivers: phy: Make NULL a valid phy reference
ARM: fix HAVE_ARM_TWD selection for OMAP and shmobile
ARM: moxart: move DMA_OF selection to driver
ARM: hisi: fix kconfig warning on HAVE_ARM_TWD
There have been reports of EFI crashes since -rc1. The following two
commits fix known issues.
* Fix boot failure on 32-bit EFI due to the recent EFI memmap changes
merged during the merge window - Borislav Petkov
* Avoid a crash during efi_bgrt_init() by detecting invalid BGRT
headers based on the 'status' field.
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM fixes from Paolo Bonzini:
"A small error handling problem and a compile breakage for ARM64"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
arm64: KVM: Add VGIC device control for arm64
KVM: return an error code in kvm_vm_ioctl_register_coalesced_mmio()
Pull x86 fixes from Peter Anvin:
"A collection of small fixes:
- There still seem to be problems with asm goto which requires the
empty asm hack.
- If SMAP is disabled at compile time, don't enable it nor try to
interpret a page fault as an SMAP violation.
- Fix a case of unbounded recursion while tracing"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, smap: smap_violation() is bogus if CONFIG_X86_SMAP is off
x86, smap: Don't enable SMAP if CONFIG_X86_SMAP is disabled
compiler/gcc4: Make quirk for asm_volatile_goto() unconditional
x86: Use preempt_disable_notrace() in cycles_2_ns()
This fixes the build breakage introduced by
c07a0191ef and adds support for the device
control API and save/restore of the VGIC state for ARMv8.
The defines were simply missing from the arm64 header files and
uaccess.h must be implicitly imported from somewhere else on arm.
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Madper reported seeing the following crash,
BUG: unable to handle kernel paging request at ffffffffff340003
IP: [<ffffffff81d85ba4>] efi_bgrt_init+0x9d/0x133
Call Trace:
[<ffffffff81d8525d>] efi_late_init+0x9/0xb
[<ffffffff81d68f59>] start_kernel+0x436/0x450
[<ffffffff81d6892c>] ? repair_env_string+0x5c/0x5c
[<ffffffff81d68120>] ? early_idt_handlers+0x120/0x120
[<ffffffff81d685de>] x86_64_start_reservations+0x2a/0x2c
[<ffffffff81d6871e>] x86_64_start_kernel+0x13e/0x14d
This is caused because the layout of the ACPI BGRT header on this system
doesn't match the definition from the ACPI spec, and so we get a bogus
physical address when dereferencing ->image_address in efi_bgrt_init().
Luckily the status field in the BGRT header clearly marks it as invalid,
so we can check that field and skip BGRT initialisation.
Reported-by: Madper Xie <cxie@redhat.com>
Suggested-by: Toshi Kani <toshi.kani@hp.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
We do not enable the new efi memmap on 32-bit and thus we need to run
runtime_code_page_mkexec() unconditionally there. Fix that.
Reported-and-tested-by: Lejun Zhu <lejun.zhu@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
If CONFIG_X86_SMAP is disabled, smap_violation() tests for conditions
which are incorrect (as the AC flag doesn't matter), causing spurious
faults.
The dynamic disabling of SMAP (nosmap on the command line) is fine
because it disables X86_FEATURE_SMAP, therefore causing the
static_cpu_has() to return false.
Found by Fengguang Wu's test system.
[ v3: move all predicates into smap_violation() ]
[ v2: use IS_ENABLED() instead of #ifdef ]
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Link: http://lkml.kernel.org/r/20140213124550.GA30497@localhost
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: <stable@vger.kernel.org> # v3.7+
If SMAP support is not compiled into the kernel, don't enable SMAP in
CR4 -- in fact, we should clear it, because the kernel doesn't contain
the proper STAC/CLAC instructions for SMAP support.
Found by Fengguang Wu's test system.
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Link: http://lkml.kernel.org/r/20140213124550.GA30497@localhost
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: <stable@vger.kernel.org> # v3.7+
Pull powerpc updates from Ben Herrenschmidt:
"Here is some powerpc goodness for -rc2. Arguably -rc1 material more
than -rc2 but I was travelling (again !)
It's mostly bug fixes including regressions, but there are a couple of
new things that I decided to drop-in.
One is a straightforward patch from Michael to add a bunch of P8 cache
events to perf.
The other one is a patch by myself to add the direct DMA (iommu
bypass) for PCIe on Power8 for 64-bit capable devices. This has been
around for a while, I had lost track of it. However it's been in our
internal kernels we use for testing P8 already and it affects only P8
related code. Since P8 is still unreleased the risk is pretty much
nil at this point"
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
powerpc/powernv: Add iommu DMA bypass support for IODA2
powerpc: Fix endian issues in kexec and crash dump code
powerpc/ppc32: Fix the bug in the init of non-base exception stack for UP
powerpc/xmon: Don't signal we've entered until we're finished printing
powerpc/xmon: Fix timeout loop in get_output_lock()
powerpc/xmon: Don't loop forever in get_output_lock()
powerpc/perf: Configure BHRB filter before enabling PMU interrupts
crypto/nx/nx-842: Fix handling of vmalloc addresses
powerpc/pseries: Select ARCH_RANDOM on pseries
powerpc/perf: Add Power8 cache & TLB events
powerpc/relocate fix relocate processing in LE mode
powerpc: Fix kdump hang issue on p8 with relocation on exception enabled.
powerpc/pseries: Disable relocation on exception while going down during crash.
powerpc/eeh: Drop taken reference to driver on eeh_rmv_device
powerpc: Fix build failure in sysdev/mpic.c for MPIC_WEIRD=y
When the conversion was made to remove stop machine and use the breakpoint
logic instead, the modification of the function graph caller is still
done directly as though it was being done under stop machine.
As it is not converted via stop machine anymore, there is a possibility
that the code could be layed across cache lines and if another CPU is
accessing that function graph call when it is being updated, it could
cause a General Protection Fault.
Convert the update of the function graph caller to use the breakpoint
method as well.
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: stable@vger.kernel.org # 3.5+
Fixes: 08d636b6d4 "ftrace/x86: Have arch x86_64 use breakpoints instead of stop machine"
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Pull s390 bugfixes from Martin Schwidefsky:
"A collection a bug fixes. Most of them are minor but two of them are
more severe. The linkage stack bug can be used by user space to force
an oops, with panic_on_oops this is a denial-of-service. And the dump
memory detection issue can cause incomplete memory dumps"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390/cio: improve cio_commit_config
s390: fix kernel crash due to linkage stack instructions
s390/dump: Fix dump memory detection
s390/appldata: restore missing init_virt_timer()
s390/qdio: correct program-controlled interruption checking
s390/qdio: for_each macro correctness
Pull networking updates from David Miller:
1) Fix flexcan build on big endian, from Arnd Bergmann
2) Correctly attach cpsw to GPIO bitbang MDIO drive, from Stefan Roese
3) udp_add_offload has to use GFP_ATOMIC since it can be invoked from
non-sleepable contexts. From Or Gerlitz
4) vxlan_gro_receive() does not iterate over all possible flows
properly, fix also from Or Gerlitz
5) CAN core doesn't use a proper SKB destructor when it hooks up
sockets to SKBs. Fix from Oliver Hartkopp
6) ip_tunnel_xmit() can use an uninitialized route pointer, fix from
Eric Dumazet
7) Fix address family assignment in IPVS, from Michal Kubecek
8) Fix ath9k build on ARM, from Sujith Manoharan
9) Make sure fail_over_mac only applies for the correct bonding modes,
from Ding Tianhong
10) The udp offload code doesn't use RCU correctly, from Shlomo Pongratz
11) Handle gigabit features properly in generic PHY code, from Florian
Fainelli
12) Don't blindly invoke link operations in
rtnl_link_get_slave_info_data_size, they are optional. Fix from
Fernando Luis Vazquez Cao
13) Add USB IDs for Netgear Aircard 340U, from Bjørn Mork
14) Handle netlink packet padding properly in openvswitch, from Thomas
Graf
15) Fix oops when deleting chains in nf_tables, from Patrick McHardy
16) Fix RX stalls in xen-netback driver, from Zoltan Kiss
17) Fix deadlock in mac80211 stack, from Emmanuel Grumbach
18) inet_nlmsg_size() forgets to consider ifa_cacheinfo, fix from Geert
Uytterhoeven
19) tg3_change_mtu() can deadlock, fix from Nithin Sujir
20) Fix regression in setting SCTP local source addresses on accepted
sockets, caused by some generic ipv6 socket changes. Fix from
Matija Glavinic Pecotic
21) IPPROTO_* must be pure defines, otherwise module aliases don't get
constructed properly. Fix from Jan Moskyto
22) IPV6 netconsole setup doesn't work properly unless an explicit
source address is specified, fix from Sabrina Dubroca
23) Use __GFP_NORETRY for high order skb page allocations in
sock_alloc_send_pskb and skb_page_frag_refill. From Eric Dumazet
24) Fix a regression added in netconsole over bridging, from Cong Wang
25) TCP uses an artificial offset of 1ms for SRTT, but this doesn't jive
well with TCP pacing which needs the SRTT to be accurate. Fix from
Eric Dumazet
26) Several cases of missing header file includes from Rashika Kheria
27) Add ZTE MF667 device ID to qmi_wwan driver, from Raymond Wanyoike
28) TCP Small Queues doesn't handle nonagle properly in some corner
cases, fix from Eric Dumazet
29) Remove extraneous read_unlock in bond_enslave, whoops. From Ding
Tianhong
30) Fix 9p trans_virtio handling of vmalloc buffers, from Richard Yao
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (136 commits)
6lowpan: fix lockdep splats
alx: add missing stats_lock spinlock init
9p/trans_virtio.c: Fix broken zero-copy on vmalloc() buffers
bonding: remove unwanted bond lock for enslave processing
USB2NET : SR9800 : One chip USB2.0 USB2NET SR9800 Device Driver Support
tcp: tsq: fix nonagle handling
bridge: Prevent possible race condition in br_fdb_change_mac_address
bridge: Properly check if local fdb entry can be deleted when deleting vlan
bridge: Properly check if local fdb entry can be deleted in br_fdb_delete_by_port
bridge: Properly check if local fdb entry can be deleted in br_fdb_change_mac_address
bridge: Fix the way to check if a local fdb entry can be deleted
bridge: Change local fdb entries whenever mac address of bridge device changes
bridge: Fix the way to find old local fdb entries in br_fdb_change_mac_address
bridge: Fix the way to insert new local fdb entries in br_fdb_changeaddr
bridge: Fix the way to find old local fdb entries in br_fdb_changeaddr
tcp: correct code comment stating 3 min timeout for FIN_WAIT2, we only do 1 min
net: vxge: Remove unused device pointer
net: qmi_wwan: add ZTE MF667
3c59x: Remove unused pointer in vortex_eisa_cleanup()
net: fix 'ip rule' iif/oif device rename
...
Commit 70b41abc15
"ARM: ux500: move MSP pin control to the device tree"
accidentally activated MSP2, giving rise to a boot scroll
scream as the kernel attempts to probe a driver for it and
fails to obtain DMA channel 14.
Fix this up by marking the node disabled again.
Acked-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Kevin Hilman <khilman@linaro.org>
This patch adds the support for to create a direct iommu "bypass"
window on IODA2 bridges (such as Power8) allowing to bypass iommu
page translation completely for 64-bit DMA capable devices, thus
significantly improving DMA performances.
Additionally, this adds a hook to the struct iommu_table so that
the IOMMU API / VFIO can disable the bypass when external ownership
is requested, since in that case, the device will be used by an
environment such as userspace or a KVM guest which must not be
allowed to bypass translations.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
We expose a number of OF properties in the kexec and crash dump code
and these need to be big endian.
Cc: stable@vger.kernel.org # v3.13
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
We would allocate one specific exception stack for each kind of
non-base exceptions for every CPU. For ppc32 the CPU hard ID is
used as the subscript to get the specific exception stack for
one CPU. But for an UP kernel, there is only one element in the
each kind of exception stack array. We would get stuck if the
CPU hard ID is not equal to '0'. So in this case we should use the
subscript '0' no matter what the CPU hard ID is.
Signed-off-by: Kevin Hao <haokexin@gmail.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Currently we set our cpu's bit in cpus_in_xmon, and then we take the
output lock and print the exception information.
This can race with the master cpu entering the command loop and printing
the backtrace. The result is that the backtrace gets garbled with
another cpu's exception print out.
Fix it by delaying the set of cpus_in_xmon until we are finished
printing.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
As far as I can tell, our 70s era timeout loop in get_output_lock() is
generating no code.
This leads to the hostile takeover happening more or less simultaneously
on all cpus. The result is "interesting", some example output that is
more readable than most:
cpu 0x1: Vector: 100 (Scypsut e0mx bR:e setV)e catto xc0p:u[ c 00
c0:0 000t0o0V0erc0td:o5 rfc28050000]0c00 0 0 0 6t(pSrycsV1ppuot
uxe 1m 2 0Rx21e3:0s0ce000c00000t00)00 60602oV2SerucSayt0y 0p 1sxs
Fix it by using udelay() in the timeout loop. The wait time and check
frequency are arbitrary, but seem to work OK. We already rely on
udelay() working so this is not a new dependency.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
If we enter with xmon_speaker != 0 we skip the first cmpxchg(), we also
skip the while loop because xmon_speaker != last_speaker (0) - meaning we
skip the second cmpxchg() also.
Following that code path the compiler sees no memory barriers and so is
within its rights to never reload xmon_speaker. The end result is we loop
forever.
This manifests as all cpus being in xmon ('c' command), but they refuse
to take control when you switch to them ('c x' for cpu # x).
I have seen this deadlock in practice and also checked the generated code to
confirm this is what's happening.
The simplest fix is just to always try the cmpxchg().
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Right now the config_bhrb() PMU specific call happens after
write_mmcr0(), which actually enables the PMU for event counting and
interrupts. So there is a small window of time where the PMU and BHRB
runs without the required HW branch filter (if any) enabled in BHRB.
This can cause some of the branch samples to be collected through BHRB
without any filter applied and hence affects the correctness of
the results. This patch moves the BHRB config function call before
enabling interrupts.
Here are some data points captured via trace prints which depicts how we
could get PMU interrupts with BHRB filter NOT enabled with a standard
perf record command line (asking for branch record information as well).
$ perf record -j any_call ls
Before the patch:-
ls-1962 [003] d... 2065.299590: .perf_event_interrupt: MMCRA: 40000000000
ls-1962 [003] d... 2065.299603: .perf_event_interrupt: MMCRA: 40000000000
...
All the PMU interrupts before this point did not have the requested
HW branch filter enabled in the MMCRA.
ls-1962 [003] d... 2065.299647: .perf_event_interrupt: MMCRA: 40040000000
ls-1962 [003] d... 2065.299662: .perf_event_interrupt: MMCRA: 40040000000
After the patch:-
ls-1850 [008] d... 190.311828: .perf_event_interrupt: MMCRA: 40040000000
ls-1850 [008] d... 190.311848: .perf_event_interrupt: MMCRA: 40040000000
All the PMU interrupts have the requested HW BHRB branch filter
enabled in MMCRA.
Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
[mpe: Fixed up whitespace and cleaned up changelog]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
We have a driver for the ARCH_RANDOM hook in rng.c, so we should select
ARCH_RANDOM on pseries.
Without this the build breaks if you turn ARCH_RANDOM off.
This hasn't broken the build because pseries_defconfig doesn't specify a
value for PPC_POWERNV, which is default y, and selects ARCH_RANDOM.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Relocation's code is not working in little endian mode because the r_info
field, which is a 64 bits value, should be read from the right offset.
The current code is optimized to read the r_info field as a 32 bits value
starting at the middle of the double word (offset 12). When running in LE
mode, the read value is not correct since only the MSB is read.
This patch removes this optimization which consist to deal with a 32 bits
value instead of a 64 bits one. This way it works in big and little endian
mode.
Signed-off-by: Laurent Dufour <ldufour@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
On p8 systems, with relocation on exception feature enabled we are seeing
kdump kernel hang at interrupt vector 0xc*4400. The reason is, with this
feature enabled, exception are raised with MMU (IR=DR=1) ON with the
default offset of 0xc*4000. Since exception is raised in virtual mode it
requires the vector region to be executable without which it fails to
fetch and execute instruction at 0xc*4xxx. For default kernel since kernel
is loaded at real 0, the htab mappings sets the entire kernel text region
executable. But for relocatable kernel (e.g. kdump case) we only copy
interrupt vectors down to real 0 and never marked that region as
executable because in p7 and below we always get exception in real mode.
This patch fixes this issue by marking htab mapping range as executable
that overlaps with the interrupt vector region for relocatable kernel.
Thanks to Ben who helped me to debug this issue and find the root cause.
Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Disable relocation on exception while going down even in kdump case. This
is because we are about clear htab mappings while kexec-ing into kdump
kernel and we may run into issues if we still have AIL ON.
Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Commit f5c57710dd ("powerpc/eeh: Use
partial hotplug for EEH unaware drivers") introduces eeh_rmv_device,
which may grab a reference to a driver, but not release it.
That prevents a driver from being removed after it has gone through EEH
recovery.
This patch drops the reference if it was taken.
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@linux.vnet.ibm.com>
Acked-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Commit 446f6d06fa ("powerpc/mpic: Properly
set default triggers") breaks the mpc7447_hpc_defconfig as follows:
CC arch/powerpc/sysdev/mpic.o
arch/powerpc/sysdev/mpic.c: In function 'mpic_set_irq_type':
arch/powerpc/sysdev/mpic.c:886:9: error: case label does not reduce to an integer constant
arch/powerpc/sysdev/mpic.c:890:9: error: case label does not reduce to an integer constant
arch/powerpc/sysdev/mpic.c:894:9: error: case label does not reduce to an integer constant
arch/powerpc/sysdev/mpic.c:898:9: error: case label does not reduce to an integer constant
Looking at the cpp output (gcc 4.7.3), I see:
case mpic->hw_set[MPIC_IDX_VECPRI_SENSE_EDGE] |
mpic->hw_set[MPIC_IDX_VECPRI_POLARITY_POSITIVE]:
The pointer into an array appears because CONFIG_MPIC_WEIRD=y is set
for this platform, thus enabling the following:
-------------------
#ifdef CONFIG_MPIC_WEIRD
static u32 mpic_infos[][MPIC_IDX_END] = {
[0] = { /* Original OpenPIC compatible MPIC */
[...]
#define MPIC_INFO(name) mpic->hw_set[MPIC_IDX_##name]
#else /* CONFIG_MPIC_WEIRD */
#define MPIC_INFO(name) MPIC_##name
#endif /* CONFIG_MPIC_WEIRD */
-------------------
Here we convert the case section to if/else if, and also add
the equivalent of a default case to warn about unknown types.
Boot tested on sbc8548, build tested on all defconfigs.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Steven Noonan forwarded a users report where they had a problem starting
vsftpd on a Xen paravirtualized guest, with this in dmesg:
BUG: Bad page map in process vsftpd pte:8000000493b88165 pmd:e9cc01067
page:ffffea00124ee200 count:0 mapcount:-1 mapping: (null) index:0x0
page flags: 0x2ffc0000000014(referenced|dirty)
addr:00007f97eea74000 vm_flags:00100071 anon_vma:ffff880e98f80380 mapping: (null) index:7f97eea74
CPU: 4 PID: 587 Comm: vsftpd Not tainted 3.12.7-1-ec2 #1
Call Trace:
dump_stack+0x45/0x56
print_bad_pte+0x22e/0x250
unmap_single_vma+0x583/0x890
unmap_vmas+0x65/0x90
exit_mmap+0xc5/0x170
mmput+0x65/0x100
do_exit+0x393/0x9e0
do_group_exit+0xcc/0x140
SyS_exit_group+0x14/0x20
system_call_fastpath+0x1a/0x1f
Disabling lock debugging due to kernel taint
BUG: Bad rss-counter state mm:ffff880e9ca60580 idx:0 val:-1
BUG: Bad rss-counter state mm:ffff880e9ca60580 idx:1 val:1
The issue could not be reproduced under an HVM instance with the same
kernel, so it appears to be exclusive to paravirtual Xen guests. He
bisected the problem to commit 1667918b64 ("mm: numa: clear numa
hinting information on mprotect") that was also included in 3.12-stable.
The problem was related to how xen translates ptes because it was not
accounting for the _PAGE_NUMA bit. This patch splits pte_present to add
a pteval_present helper for use by xen so both bare metal and xen use
the same code when checking if a PTE is present.
[mgorman@suse.de: wrote changelog, proposed minor modifications]
[akpm@linux-foundation.org: fix typo in comment]
Reported-by: Steven Noonan <steven@uplinklabs.net>
Tested-by: Steven Noonan <steven@uplinklabs.net>
Signed-off-by: Elena Ufimtseva <ufimtseva@gmail.com>
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: <stable@vger.kernel.org> [3.12+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Reserve space from 0x0 - __pa(swapper_pg_dir),
if kernel is loaded from 0, which is not DMAable.
It is causing problem with MMC driver and others
which want to add dma buffers to this space.
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Kevin Hilman <khilman@linaro.org>
All of them are DT-related.
- fixes for typos in i2c and ohci clocks
- addition of a USB host node for at91sam9n12ek
- 2 DT documentation updates that have been sent a long time ago
- a new board based on the sama5d36 SoC
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Merge tag 'at91-fixes' of git://github.com/at91linux/linux-at91 into fixes
From Nicolas Ferre:
First series of AT91 fixes for 3.14.
All of them are DT-related.
- fixes for typos in i2c and ohci clocks
- addition of a USB host node for at91sam9n12ek
- 2 DT documentation updates that have been sent a long time ago
- a new board based on the sama5d36 SoC
* tag 'at91-fixes' of git://github.com/at91linux/linux-at91:
ARM: at91: add Atmel's SAMA5D3 Xplained board
spi/atmel: document clock properties
mmc: atmel-mci: document clock properties
ARM: at91: enable USB host on at91sam9n12ek board
ARM: at91/dt: fix sama5d3 ohci hclk clock reference
ARM: at91/dt: sam9263: fix compatibility string for the I2C
Signed-off-by: Kevin Hilman <khilman@linaro.org>
Select CONFIG_SOC_DRA7XX so that we can boot dra7-evm.
DRA7 family are A15 based processors that supports LPAE and an
evolutionary update to the OMAP5 generation of processors.
Signed-off-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Kevin Hilman <khilman@linaro.org>
Since commit 9e8147bb5e
"ARM: imx6q: move low-power code out of clock driver"
the kernel fails to boot on i.MX6Q/D if preemption is
enabled (CONFIG_PREEMPT=y). The kernel just hangs
before the console comes up.
The above commit moved the initalization of the low-power
mode setting (enabling clocked WAIT states), which was
introduced in commit 83ae20981a
"ARM: imx: correct low-power mode setting", from
imx6q_clks_init to imx6q_pm_init. Now it is called
much later, after all cores are enabled.
This patch moves the low-power mode initialization back
to imx6q_clks_init again (and to imx6sl_clks_init).
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Kevin Hilman <khilman@linaro.org>
Due to commit 88f718e3fa
"ARM: pxa: delete the custom GPIO header" some drivers fail
compilation, for example like this:
In file included from sound/soc/pxa/spitz.c:28:0:
sound/soc/pxa/spitz.c: In function ‘spitz_ext_control’:
arch/arm/mach-pxa/include/mach/spitz.h:111:30: error:
‘PXA_NR_BUILTIN_GPIO’ undeclared (first use in this function)
#define SPITZ_SCP_GPIO_BASE (PXA_NR_BUILTIN_GPIO)
(etc.)
This is caused by implicit inclusion of <mach/irqs.h> from
various board-specific headers under <mach/*> in the PXA
platform. So we take a sweep over these, and for every such
header that uses PXA_NR_BUILTIN_GPIO or PXA_GPIO_TO_IRQ()
we explicitly #include "irqs.h" so that we satisfy the
dependency in the board include file alone.
Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Cc: stable@vger.kernel.org # v3.13+
Signed-off-by: Kevin Hilman <khilman@linaro.org>
This board fails compilation like this:
arch/arm/mach-pxa/am300epd.c: In function ‘am300_cleanup’:
arch/arm/mach-pxa/am300epd.c:179:2: error: implicit declaration
of function ‘PXA_GPIO_TO_IRQ’ [-Werror=implicit-function-declaration]
free_irq(PXA_GPIO_TO_IRQ(RDY_GPIO_PIN), par);
This was caused by commit 88f718e3fa
"ARM: pxa: delete the custom GPIO header"
This is because it was previously getting the macro PXA_GPIO_TO_IRQ
implicitly from <linux/gpio.h> which in turn implicitly included
<mach/gpio.h> which in turn included <mach/irqs.h>.
Add the missing include so that the board compiles again.
Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Kevin Hilman <khilman@linaro.org>
Correct a typo causing the stack protector to be left enabled.
0xFFFFFFF -> 0xFFFFFFFF
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Some drivers check if readq/writeq functions are defined.
If not internal driver functions are used which cause
compilation failures.
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Add missing param.h header because of HZ macro.
It is causing compilation failure:
In file included from include/linux/delay.h:14:0,
from drivers/clk/qcom/reset.c:18:
drivers/clk/qcom/reset.c: In function 'qcom_reset':
arch/microblaze/include/asm/delay.h:39:35: error: 'HZ'
undeclared (first use in this function)
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
When debug preempt is enabled, preempt_disable() can be traced by
function and function graph tracing.
There's a place in the function graph tracer that calls trace_clock()
which eventually calls cycles_2_ns() outside of the recursion
protection. When cycles_2_ns() calls preempt_disable() it gets traced
and the graph tracer will go into a recursive loop causing a crash or
worse, a triple fault.
Simple fix is to use preempt_disable_notrace() in cycles_2_ns, which
makes sense because the preempt_disable() tracing may use that code
too, and it tracing it, even with recursion protection is rather
pointless.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20140204141315.2a968a72@gandalf.local.home
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull x86 fixes from Peter Anvin:
"Quite a varied little collection of fixes. Most of them are
relatively small or isolated; the biggest one is Mel Gorman's fixes
for TLB range flushing.
A couple of AMD-related fixes (including not crashing when given an
invalid microcode image) and fix a crash when compiled with gcov"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, microcode, AMD: Unify valid container checks
x86, hweight: Fix BUG when booting with CONFIG_GCOV_PROFILE_ALL=y
x86/efi: Allow mapping BGRT on x86-32
x86: Fix the initialization of physnode_map
x86, cpu hotplug: Fix stack frame warning in check_irq_vectors_for_cpu_disable()
x86/intel/mid: Fix X86_INTEL_MID dependencies
arch/x86/mm/srat: Skip NUMA_NO_NODE while parsing SLIT
mm, x86: Revisit tlb_flushall_shift tuning for page flushes except on IvyBridge
x86: mm: change tlb_flushall_shift for IvyBridge
x86/mm: Eliminate redundant page table walk during TLB range flushing
x86/mm: Clean up inconsistencies when flushing TLB ranges
mm, x86: Account for TLB flushes only when debugging
x86/AMD/NB: Fix amd_set_subcaches() parameter type
x86/quirks: Add workaround for AMD F16h Erratum792
x86, doc, kconfig: Fix dud URL for Microcode data
does not conflict with the dynamic linker's one (64K)
- VDSO gettimeofday fix
- Barrier fixes for atomic operations and cache flushing
- TLB invalidation when overriding early page mappings during boot
- Wired up new 32-bit arm (compat) syscalls
- LSM_MMAP_MIN_ADDR when COMPAT is enabled
- defconfig update
- Clean-up (comments, pgd_alloc).
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Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 fixes from Catalin Marinas:
- Relax VDSO alignment requirements so that the kernel-picked one (4K)
does not conflict with the dynamic linker's one (64K)
- VDSO gettimeofday fix
- Barrier fixes for atomic operations and cache flushing
- TLB invalidation when overriding early page mappings during boot
- Wired up new 32-bit arm (compat) syscalls
- LSM_MMAP_MIN_ADDR when COMPAT is enabled
- defconfig update
- Clean-up (comments, pgd_alloc).
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64: defconfig: Expand default enabled features
arm64: asm: remove redundant "cc" clobbers
arm64: atomics: fix use of acquire + release for full barrier semantics
arm64: barriers: allow dsb macro to take option parameter
security: select correct default LSM_MMAP_MIN_ADDR on arm on arm64
arm64: compat: Wire up new AArch32 syscalls
arm64: vdso: update wtm fields for CLOCK_MONOTONIC_COARSE
arm64: vdso: fix coarse clock handling
arm64: simplify pgd_alloc
arm64: fix typo: s/SERRROR/SERROR/
arm64: Invalidate the TLB when replacing pmd entries during boot
arm64: Align CMA sizes to PAGE_SIZE
arm64: add DSB after icache flush in __flush_icache_all()
arm64: vdso: prevent ld from aligning PT_LOAD segments to 64k
Pull MIPS updates from Ralf Baechle:
"hree minor patches. All have sat in -next for a few days"
* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus:
MIPS: fpu.h: Fix build when CONFIG_BUG is not set
MIPS: Wire up sched_setattr/sched_getattr syscalls
MIPS: Alchemy: Fix DB1100 GPIO registration
FPGA implementations of the Cortex-A57 and Cortex-A53 are now available
in the form of the SMM-A57 and SMM-A53 Soft Macrocell Models (SMMs) for
Versatile Express. As these attach to a Motherboard Express V2M-P1 it
would be useful to have support for some V2M-P1 peripherals enabled by
default.
Additionally a couple of of features have been introduced since the last
defconfig update (CMA, jump labels) that would be good to have enabled
by default to ensure they are build and boot tested.
This patch updates the arm64 defconfig to enable support for these
devices and features. The arm64 Kconfig is modified to select
HAVE_PATA_PLATFORM, which is required to enable support for the
CompactFlash controller on the V2M-P1.
A few options which don't need to appear in defconfig are trimmed:
* BLK_DEV - selected by default
* EXPERIMENTAL - otherwise gone from the kernel
* MII - selected by drivers which require it
* USB_SUPPORT - selected by default
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
cbnz/tbnz don't update the condition flags, so remove the "cc" clobbers
from inline asm blocks that only use these instructions to implement
conditional branches.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Linux requires a number of atomic operations to provide full barrier
semantics, that is no memory accesses after the operation can be
observed before any accesses up to and including the operation in
program order.
On arm64, these operations have been incorrectly implemented as follows:
// A, B, C are independent memory locations
<Access [A]>
// atomic_op (B)
1: ldaxr x0, [B] // Exclusive load with acquire
<op(B)>
stlxr w1, x0, [B] // Exclusive store with release
cbnz w1, 1b
<Access [C]>
The assumption here being that two half barriers are equivalent to a
full barrier, so the only permitted ordering would be A -> B -> C
(where B is the atomic operation involving both a load and a store).
Unfortunately, this is not the case by the letter of the architecture
and, in fact, the accesses to A and C are permitted to pass their
nearest half barrier resulting in orderings such as Bl -> A -> C -> Bs
or Bl -> C -> A -> Bs (where Bl is the load-acquire on B and Bs is the
store-release on B). This is a clear violation of the full barrier
requirement.
The simple way to fix this is to implement the same algorithm as ARMv7
using explicit barriers:
<Access [A]>
// atomic_op (B)
dmb ish // Full barrier
1: ldxr x0, [B] // Exclusive load
<op(B)>
stxr w1, x0, [B] // Exclusive store
cbnz w1, 1b
dmb ish // Full barrier
<Access [C]>
but this has the undesirable effect of introducing *two* full barrier
instructions. A better approach is actually the following, non-intuitive
sequence:
<Access [A]>
// atomic_op (B)
1: ldxr x0, [B] // Exclusive load
<op(B)>
stlxr w1, x0, [B] // Exclusive store with release
cbnz w1, 1b
dmb ish // Full barrier
<Access [C]>
The simple observations here are:
- The dmb ensures that no subsequent accesses (e.g. the access to C)
can enter or pass the atomic sequence.
- The dmb also ensures that no prior accesses (e.g. the access to A)
can pass the atomic sequence.
- Therefore, no prior access can pass a subsequent access, or
vice-versa (i.e. A is strictly ordered before C).
- The stlxr ensures that no prior access can pass the store component
of the atomic operation.
The only tricky part remaining is the ordering between the ldxr and the
access to A, since the absence of the first dmb means that we're now
permitting re-ordering between the ldxr and any prior accesses.
From an (arbitrary) observer's point of view, there are two scenarios:
1. We have observed the ldxr. This means that if we perform a store to
[B], the ldxr will still return older data. If we can observe the
ldxr, then we can potentially observe the permitted re-ordering
with the access to A, which is clearly an issue when compared to
the dmb variant of the code. Thankfully, the exclusive monitor will
save us here since it will be cleared as a result of the store and
the ldxr will retry. Notice that any use of a later memory
observation to imply observation of the ldxr will also imply
observation of the access to A, since the stlxr/dmb ensure strict
ordering.
2. We have not observed the ldxr. This means we can perform a store
and influence the later ldxr. However, that doesn't actually tell
us anything about the access to [A], so we've not lost anything
here either when compared to the dmb variant.
This patch implements this solution for our barriered atomic operations,
ensuring that we satisfy the full barrier requirements where they are
needed.
Cc: <stable@vger.kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Add DT file for new SAMA5D3 Xplained board.
This board is based on Atmel's SAMA5D36 Cortex-A5 SoC.
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Linus Torvalds