This reverts commits 5d17a73a2e ("vmalloc: back off when the current
task is killed") and 171012f561 ("mm: don't warn when vmalloc() fails
due to a fatal signal").
Commit 5d17a73a2e ("vmalloc: back off when the current task is
killed") made all vmalloc allocations from a signal-killed task fail.
We have seen crashes in the tty driver from this, where a killed task
exiting tries to switch back to N_TTY, fails n_tty_open because of the
vmalloc failing, and later crashes when dereferencing tty->disc_data.
Arguably, relying on a vmalloc() call to succeed in order to properly
exit a task is not the most robust way of doing things. There will be a
follow-up patch to the tty code to fall back to the N_NULL ldisc.
But the justification to make that vmalloc() call fail like this isn't
convincing, either. The patch mentions an OOM victim exhausting the
memory reserves and thus deadlocking the machine. But the OOM killer is
only one, improbable source of fatal signals. It doesn't make sense to
fail allocations preemptively with plenty of memory in most cases.
The patch doesn't mention real-life instances where vmalloc sites would
exhaust memory, which makes it sound more like a theoretical issue to
begin with. But just in case, the OOM access to memory reserves has
been restricted on the allocator side in cd04ae1e2d ("mm, oom: do not
rely on TIF_MEMDIE for memory reserves access"), which should take care
of any theoretical concerns on that front.
Revert this patch, and the follow-up that suppresses the allocation
warnings when we fail the allocations due to a signal.
Link: http://lkml.kernel.org/r/20171004185906.GB2136@cmpxchg.org
Fixes: 171012f561 ("mm: don't warn when vmalloc() fails due to a fatal signal")
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Alan Cox <alan@llwyncelyn.cymru>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
gcc on aarch64 may emit synbols of type 'n' if the kernel is built with
'-frecord-gcc-switches'. In most cases, those symbols are reported with
nm as
000000000000000e n $d
and with objdump as
0000000000000000 l d .GCC.command.line 0000000000000000 .GCC.command.line
000000000000000e l .GCC.command.line 0000000000000000 $d
Those symbols are detected in is_arm_mapping_symbol() and ignored.
However, if "--prefix-symbols=<prefix>" is configured as well, the
situation is different. For example, in efi/libstub, arm64 images are
built with
'--prefix-alloc-sections=.init --prefix-symbols=__efistub_'.
In combination with '-frecord-gcc-switches', the symbols are now reported
by nm as:
000000000000000e n __efistub_$d
and by objdump as:
0000000000000000 l d .GCC.command.line 0000000000000000 .GCC.command.line
000000000000000e l .GCC.command.line 0000000000000000 __efistub_$d
Those symbols are no longer ignored and included in the base address
calculation. This results in a base address of 000000000000000e, which
in turn causes kallsyms to abort with
kallsyms failure:
relative symbol value 0xffffff900800a000 out of range in relative mode
The problem is seen in little endian arm64 builds with CONFIG_EFI
enabled and with '-frecord-gcc-switches' set in KCFLAGS.
Explicitly ignore symbols of type 'n' since those are clearly debug
symbols.
Link: http://lkml.kernel.org/r/1507136063-3139-1-git-send-email-linux@roeck-us.net
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
I was stress testing some backports and with high load, after some time,
the latest version of the selftest showed some false positive in
connection with the uffdio_copy_retry. This seems to fix it while still
exercising -EEXIST in the background transfer once in a while.
The fork child will quit after the last UFFDIO_COPY is run, so a
repeated UFFDIO_COPY may not return -EEXIST. This change restricts the
-EEXIST stress to the background transfer where the memory can't go away
from under it.
Also updated uffdio_zeropage, so the interface is consistent.
Link: http://lkml.kernel.org/r/20171004171541.1495-2-aarcange@redhat.com
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Pavel Emelyanov <xemul@virtuozzo.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When I execute numactl -H (which reads /sys/devices/system/node/nodeX/cpumap
and displays cpumask_of_node for each node), I get different result
on X86 and arm64. For each numa node, the former only displayed online
CPUs, and the latter displayed all possible CPUs. Unfortunately, both
Linux documentation and numactl manual have not described it clear.
I sent a mail to ask for help, and Michal Hocko replied that he
preferred to print online cpus because it doesn't really make much sense
to bind anything on offline nodes.
Will said:
"I suspect the vast majority (if not all) code that reads this file was
developed for x86, so having the same behaviour for arm64 sounds like
something we should do ASAP before people try to special case with
things like #ifdef __aarch64__. I'd rather have this in 4.14 if
possible."
Link: http://lkml.kernel.org/r/1506678805-15392-2-git-send-email-thunder.leizhen@huawei.com
Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Tianhong Ding <dingtianhong@huawei.com>
Cc: Hanjun Guo <guohanjun@huawei.com>
Cc: Libin <huawei.libin@huawei.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The pci-rcar driver is enabled for compile tests, and this has shown that
the driver cannot build without CONFIG_OF, following the inclusion of
commit f8f2fe7355 ("PCI: rcar: Use new OF interrupt mapping when possible"):
drivers/pci/host/pcie-rcar.c: In function 'pci_dma_range_parser_init':
drivers/pci/host/pcie-rcar.c:1039:2: error: implicit declaration of function 'of_n_addr_cells' [-Werror=implicit-function-declaration]
parser->pna = of_n_addr_cells(node);
^
As pointed out by Ben Dooks and Geert Uytterhoeven, this is actually
supposed to build fine, which we can achieve if we make the declaration
of of_irq_parse_and_map_pci conditional on CONFIG_OF and provide an
empty inline function otherwise, as we do for a lot of other of
interfaces.
This lets us build the rcar_pci driver again without CONFIG_OF for build
testing. All platforms using this driver select OF, so this doesn't
change anything for the users.
[akpm@linux-foundation.org: be consistent with surrounding code]
Link: http://lkml.kernel.org/r/20170911200805.3363318-1-arnd@arndb.de
Fixes: c25da47788 ("PCI: rcar: Add Renesas R-Car PCIe driver")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Frank Rowand <frank.rowand@sony.com>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Magnus Damm <damm@opensource.se>
Cc: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull IOMMU fixes from Joerg Roedel:
- keep an important data structure in the Exynos driver around after
kernel-init to fix a kernel-oops
- keep SWIOTLB enabled when SME is active in the AMD IOMMU driver
- add a missing IOTLB sync to the AMD IOMMU driver
* tag 'iommu-fixes-v4.14-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
iommu/amd: Finish TLB flush in amd_iommu_unmap()
iommu/exynos: Remove initconst attribute to avoid potential kernel oops
iommu/amd: Do not disable SWIOTLB if SME is active
Pull DeviceTree fixes from Rob Herring:
- Fix memory leak in error case of of_console_check
- Increase number of reserved memory regions to 32. 16 was not enough
on some Power systems.
- Fix OF node refcounting for of_fwnode_graph_get_port_parent
* tag 'devicetree-fixes-for-4.14-2' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux:
device property: preserve usecount for node passed to of_fwnode_graph_get_port_parent()
drivers: of: increase MAX_RESERVED_REGIONS to 32
of: do not leak console options
Pull powerpc fixes from Michael Ellerman:
"A fix for a bad bug (written by me) in our livepatch handler. Removal
of an over-zealous lockdep_assert_cpus_held() in our topology code. A
fix to the recently added emulation of cntlz[wd]. And three small
fixes to the recently added IMC PMU driver.
Thanks to: Anju T Sudhakar, Balbir Singh, Kamalesh Babulal, Naveen N.
Rao, Sandipan Das, Santosh Sivaraj, Thiago Jung Bauermann"
* tag 'powerpc-4.14-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/perf: Fix IMC initialization crash
powerpc/perf: Add ___GFP_NOWARN flag to alloc_pages_node()
powerpc/perf: Fix for core/nest imc call trace on cpuhotplug
powerpc: Don't call lockdep_assert_cpus_held() from arch_update_cpu_topology()
powerpc/lib/sstep: Fix count leading zeros instructions
powerpc/livepatch: Fix livepatch stack access
Pull xen fixlet from Juergen Gross:
"A minor fix correcting the cpu hotplug name for Xen guests"
* tag 'for-linus-4.14c-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
xen/vcpu: Use a unified name about cpu hotplug state for pv and pvhvm
The function only sends the flush command to the IOMMU(s),
but does not wait for its completion when it returns. Fix
that.
Fixes: 601367d76b ('x86/amd-iommu: Remove iommu_flush_domain function')
Cc: stable@vger.kernel.org # >= 2.6.33
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Panic observed with latest firmware, and upstream kernel:
NIP init_imc_pmu+0x8c/0xcf0
LR init_imc_pmu+0x2f8/0xcf0
Call Trace:
init_imc_pmu+0x2c8/0xcf0 (unreliable)
opal_imc_counters_probe+0x300/0x400
platform_drv_probe+0x64/0x110
driver_probe_device+0x3d8/0x580
__driver_attach+0x14c/0x1a0
bus_for_each_dev+0x8c/0xf0
driver_attach+0x34/0x50
bus_add_driver+0x298/0x350
driver_register+0x9c/0x180
__platform_driver_register+0x5c/0x70
opal_imc_driver_init+0x2c/0x40
do_one_initcall+0x64/0x1d0
kernel_init_freeable+0x280/0x374
kernel_init+0x24/0x160
ret_from_kernel_thread+0x5c/0x74
While registering nest imc at init, cpu-hotplug callback
nest_pmu_cpumask_init() makes an OPAL call to stop the engine. And if
the OPAL call fails, imc_common_cpuhp_mem_free() is invoked to cleanup
memory and cpuhotplug setup.
But when cleaning up the attribute group, we are dereferencing the
attribute element array without checking whether the backing element
is not NULL. This causes the kernel panic.
Add a check for the backing element prior to dereferencing the
attribute element, to handle the failing case gracefully.
Signed-off-by: Anju T Sudhakar <anju@linux.vnet.ibm.com>
Reported-by: Pridhiviraj Paidipeddi <ppaidipe@linux.vnet.ibm.com>
[mpe: Trim change log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Pull device properties framework fixes from Rafael Wysocki:
"These fix an issue related to device removal introduced during the 4.9
cycle and fix up new functionality added recently.
Specifics:
- Fix a device properties management issue, introduced during the 4.9
cycle, that causes device properties associated with a parent
device to go away on a removal of its child in some cases (Jarkko
Nikula).
- Fix inconsistencies in error codes returned by a new function
helper in the device properties framework depending on the
underlying low-level firmware interface, DT or ACPI, by making the
meaning of error codes returned in the ACPI case agree with the
meaning of DT error codes in analogous situations (Sakari Ailus)"
* tag 'devprop-4.14-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
ACPI: properties: Fix __acpi_node_get_property_reference() return codes
ACPI: properties: Align return codes of __acpi_node_get_property_reference()
device property: Track owner device of device property
Pull xfs fixes from Darrick Wong:
- Fix a stale kernel memory exposure when logging inodes.
- Fix some build problems with CONFIG_XFS_RT=n
- Don't change inode mode if the acl write fails, leaving the file
totally inaccessible.
- Fix a dangling pointer problem when removing an attr fork under
memory pressure.
- Don't crash while trying to invalidate a null buffer associated with
a corrupt metadata pointer.
* tag 'xfs-4.14-fixes-5' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
xfs: handle error if xfs_btree_get_bufs fails
xfs: reinit btree pointer on attr tree inactivation walk
xfs: Fix bool initialization/comparison
xfs: don't change inode mode if ACL update fails
xfs: move more RT specific code under CONFIG_XFS_RT
xfs: Don't log uninitialised fields in inode structures
If faddr2line is given a function name which is the last one listed by
"nm -n", it will fail because it never finds the next symbol.
So teach the awk script to catch that possibility, and use 'size' to
provide the end point of the last function.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull quota fix from Jan Kara:
"A fix for a regression in handling of quota grace times and warnings"
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
quota: Generate warnings for DQUOT_SPACE_NOFAIL allocations
Pull kvm fixes from Paolo Bonzini:
"Another latent bug related to PCID, an out-of-bounds access, and a
submaintainer change being finally made official"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
MAINTAINERS: Add Paul Mackerras as maintainer for KVM/powerpc
KVM: nVMX: fix guest CR4 loading when emulating L2 to L1 exit
KVM: MMU: always terminate page walks at level 1
KVM: nVMX: update last_nonleaf_level when initializing nested EPT
Using CONFIG_OF_DYNAMIC=y uncovered an imbalance in the usecount of the
node being passed to of_fwnode_graph_get_port_parent(). Preserve the
usecount by using of_get_parent() instead of of_get_next_parent() which
don't decrement the usecount of the node passed to it.
Fixes: 3b27d00e7b ("device property: Move fwnode graph ops to firmware specific locations")
Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Rob Herring <robh@kernel.org>
There are two types of memory reservations firmware can ask the kernel
to make in the device tree: static and dynamic.
See Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt
If you have greater than 16 entries in /reserved-memory (as we do on
POWER9 systems) you would get this scary looking error message:
[ 0.000000] OF: reserved mem: not enough space all defined regions.
This is harmless if all your reservations are static (which with OPAL on
POWER9, they are).
It is not harmless if you have any dynamic reservations after the 16th.
In the first pass over the fdt to find reservations, the child nodes of
/reserved-memory are added to a static array in of_reserved_mem.c so that
memory can be reserved in a 2nd pass. The array has 16 entries. This is why,
on my dual socket POWER9 system, I get that error 4 times with 20 static
reservations.
We don't have a problem on ppc though, as in arch/powerpc/kernel/prom.c
we look at the new style /reserved-ranges property to do reservations,
and this logic was introduced in 0962e8004e (well before any powernv
system shipped).
A Google search shows up no occurances of that exact error message, so we're
probably safe in that no machine that people use has memory not being reserved
when it should be.
The simple fix is to bump the length of the array to 32 which "should be
enough for everyone(TM)". The simple fix of not recording static allocations
in the array would cause problems for devices with "memory-region" properties.
A more future-proof fix is likely possible, although more invasive and this
simple fix is perfectly suitable in the meantime while a more future-proof
fix is developed.
Signed-off-by: Stewart Smith <stewart@linux.vnet.ibm.com>
Tested-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Do not strdup() console options. It seems that the only reason for
it to be strdup()-ed was a compilation warning: printk, UART and
console drivers, for some reason, expect char pointer instead of
const char pointer. So we can just pass `of_stdout_options', but
need to cast it to char pointer. A better fix would be to change
printk, console drivers and UART to accept const char `options';
but that will take time - there are lots of drivers to update.
The patch also fixes a possible memory leak: add_preferred_console()
can fail, but we don't kfree() options.
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Rob Herring <robh@kernel.org>
