Pull two powerpc fixes from Ben Herrenschmidt:
"Here are a couple of fixes for 3.15. One from Anton fixes a nasty
regression I introduced when trying to fix a loss of irq_work whose
consequences is that we can completely lose timer interrupts on a
CPU... not pretty.
The other one is a change to our PCIe reset hook to use a firmware
call instead of direct config space accesses to trigger a fundamental
reset on the root port. This is necessary so that the FW gets a
chance to disable the link down error monitoring, which would
otherwise trip and cause subsequent fatal EEH error"
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
powerpc: irq work racing with timer interrupt can result in timer interrupt hang
powerpc/powernv: Reset root port in firmware
Pull renameat2 arch support from Miklos Szeredi:
"I've collected architecture patches for the renameat2 syscall that
maintainers acked and/or asked me to queue.
This adds architecture support for the renameat2 syscall to m68k,
parisc, ia64 and through asm-generic to arc, arm64, c6x, hexagon,
metag, openrisc, score, tile, unicore32"
* 'renameat2' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs:
scripts/checksyscalls.sh: Make renameat optional
asm-generic: Add renameat2 syscall
ia64: add renameat2 syscall
parisc: add renameat2 syscall
m68k: add renameat2 syscall
Pull staging driver fixes from Greg KH:
"Here are five staging driver fixes for 3.15-rc6 that resolve some
reported issues. They are for the imx and rtl8723au drivers"
* tag 'staging-3.15-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
staging: rtl8723au: Do not reset wdev->iftype in netdev_close()
staging: rtl8723au: Use correct pipe type for USB interrupts
imx-drm: imx-tve: correct DDC property name to 'ddc-i2c-bus'
imx-drm: imx-drm-core: skip components whose parent device is disabled
imx-drm: imx-drm-core: fix imx_drm_encoder_get_mux_id
Pull crypto fixes from Herbert Xu:
"This fixes a NULL pointer dereference on allocation failure in caam,
as well as a regression in the ctr mode on s390 that was added with
the recent concurrency fixes"
* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
crypto: s390 - fix aes,des ctr mode concurrency finding.
crypto: caam - add allocation failure handling in SPRINTFCAT macro
Pull device tree fixes from Grant Likely:
"Drivercore bugfixes for v3.15
This branch contains bug fixes important to get into v3.15. There is
a fix for modifying properties seen during early boot, a fix for an
incorrect prototype when CONFIG_OF=n, and a couple of corrections to
device tree memory nodes on a few platforms"
* tag 'dt-for-linus' of git://git.secretlab.ca/git/linux:
mips: dts: Fix missing device_type="memory" property in memory nodes
arm: dts: Fix missing device_type="memory" for ste-ccu8540
of: fix CONFIG_OF=n prototype of of_node_full_name()
of: make of_update_property() usable earlier in the boot process
Pull MIPS fixes from Ralf Baechle:
"MIPS fixes for various loose ends:
- Fix workarounds for R4000 erratum.
- Patch up DEC, Siemens-Nixdorf and Loongson hardware support.
- Wire up renameat2 syscall.
- Delete unused file - it was causing false warnings from maintenance
scripts.
- Revert a patch because it's functionality is now implemented twice
which causes superfluous /proc/cpuinfo output.
- Fix a microMIPS regression"
* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus:
MIPS: mm: Fix broken microMIPS kernel regression.
MIPS: Add new AUDIT_ARCH token for the N32 ABI on MIPS64
MIPS: Wire up renameat2 syscall.
MIPS: inst.h: Rename BITFIELD_FIELD to __BITFIELD_FIELD.
MIPS: Remove file missed when removing rm9k support a while ago.
MIPS/loongson2_cpufreq: Fix CPU clock rate setting
MIPS: Loongson: No need to select GENERIC_HARDIRQS_NO__DO_IRQ
MIPS: csum_partial.S CPU_DADDI_WORKAROUNDS bug fix
MIPS: __strncpy_from_user_asm CPU_DADDI_WORKAROUNDS bug fix
MIPS: __delay CPU_DADDI_WORKAROUNDS bug fix
MIPS: DEC/SNI: O32 wrapper stack switching fixes
MIPS: DEC: Bus error handler <asm/cpu-type.h> fixes
MAINTAINERS: TURBOchannel: Update entry
Revert "MIPS: MT: proc: Add support for printing VPE and TC ids"
Pull parisc fixes from Helge Deller:
"There are two patches in here:
The first patch greatly improves latency and corrects the memory
ordering in our light-weight atomic locking syscall.
The second patch ratelimits printing of userspace segfaults in the
same way as it's done on other platforms. This fixes a possible DOS
on parisc since it prevents the syslog to grow too fast. For example,
when the debian acl2 package was built on our debian buildd servers,
this package produced lots of gigabytes in syslog in very short time
and thus filled our harddisks, which then turned the server nearly
completely unaccessible and unresponsive"
* 'parisc-3.15-4' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
parisc: Improve LWS-CAS performance
parisc: ratelimit userspace segfault printing
Pull two arm64 fixes from Catalin Marinas:
- arm64 migrate_irqs() fix following commit ffde1de640 (irqchip: Gic:
Support forced affinity setting)
- fix arm64 pud_huge() to return 0 when only 2 levels page tables are
used (__PAGETABLE_PMD_FOLDED defined and pmd_huge already covers
block entries at the first level), otherwise KVM gets confused
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64: fix pud_huge() for 2-level pagetables
arm64: use cpu_online_mask when using forced irq_set_affinity
Pull Metag architecture and related fixes from James Hogan:
"Mostly fixes for metag and parisc relating to upgrowing stacks.
- Fix missing compiler barriers in metag memory barriers.
- Fix BUG_ON on metag when RLIMIT_STACK hard limit is increased
beyond safe value.
- Make maximum stack size configurable. This reduces the default
user stack size back to 80MB (especially on parisc after their
removal of _STK_LIM_MAX override). This only affects metag and
parisc.
- Remove metag _STK_LIM_MAX override to match other arches and follow
parisc, now that it is safe to do so (due to the BUG_ON fix
mentioned above).
- Finally now that both metag and parisc _STK_LIM_MAX overrides have
been removed, it makes sense to remove _STK_LIM_MAX altogether"
* tag 'metag-for-v3.15-2' of git://git.kernel.org/pub/scm/linux/kernel/git/jhogan/metag:
asm-generic: remove _STK_LIM_MAX
metag: Remove _STK_LIM_MAX override
parisc,metag: Do not hardcode maximum userspace stack size
metag: Reduce maximum stack size to 256MB
metag: fix memory barriers
Pull x86 fixes from Peter Anvin.
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86-64, modify_ldt: Make support for 16-bit segments a runtime option
x86, mm, hugetlb: Add missing TLB page invalidation for hugetlb_cow()
x86, rdrand: When nordrand is specified, disable RDSEED as well
The following happens when trying to run a kvm guest on a kernel
configured for 64k pages. This doesn't happen with 4k pages:
BUG: failure at include/linux/mm.h:297/put_page_testzero()!
Kernel panic - not syncing: BUG!
CPU: 2 PID: 4228 Comm: qemu-system-aar Tainted: GF 3.13.0-0.rc7.31.sa2.k32v1.aarch64.debug #1
Call trace:
[<fffffe0000096034>] dump_backtrace+0x0/0x16c
[<fffffe00000961b4>] show_stack+0x14/0x1c
[<fffffe000066e648>] dump_stack+0x84/0xb0
[<fffffe0000668678>] panic+0xf4/0x220
[<fffffe000018ec78>] free_reserved_area+0x0/0x110
[<fffffe000018edd8>] free_pages+0x50/0x88
[<fffffe00000a759c>] kvm_free_stage2_pgd+0x30/0x40
[<fffffe00000a5354>] kvm_arch_destroy_vm+0x18/0x44
[<fffffe00000a1854>] kvm_put_kvm+0xf0/0x184
[<fffffe00000a1938>] kvm_vm_release+0x10/0x1c
[<fffffe00001edc1c>] __fput+0xb0/0x288
[<fffffe00001ede4c>] ____fput+0xc/0x14
[<fffffe00000d5a2c>] task_work_run+0xa8/0x11c
[<fffffe0000095c14>] do_notify_resume+0x54/0x58
In arch/arm/kvm/mmu.c:unmap_range(), we end up doing an extra put_page()
on the stage2 pgd which leads to the BUG in put_page_testzero(). This
happens because a pud_huge() test in unmap_range() returns true when it
should always be false with 2-level pages tables used by 64k pages.
This patch removes support for huge puds if 2-level pagetables are
being used.
Signed-off-by: Mark Salter <msalter@redhat.com>
[catalin.marinas@arm.com: removed #ifndef around PUD_SIZE check]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: <stable@vger.kernel.org> # v3.11+
The attached change significantly improves the performance of the LWS-CAS code
in syscall.S.
This allows a number of packages to build (e.g., zeromq3, gtest and libxs)
that previously failed because slow LWS-CAS performance under contention. In
particular, interrupts taken while the lock was taken degraded performance
significantly.
The change does the following:
1) Disables interrupts around the CAS operation, and
2) Changes the loads and stores to use the ordered completer, "o", on
PA 2.0. "o" and "ma" with a zero offset are equivalent. The latter is
accepted on both PA 1.X and 2.0.
The use of ordered loads and stores probably makes no difference on all
existing hardware, but it seemed pedantically correct. In particular, the CAS
operation must complete before LDCW lock is released. As written before, a
processor could reorder the operations.
I don't believe the period interrupts are disabled is long enough to
significantly increase interrupt latency. For example, the TLB insert code is
longer. Worst case is a memory fault in the CAS operation.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Cc: stable@vger.kernel.org # 3.13+
Signed-off-by: Helge Deller <deller@gmx.de>
Ratelimit printing of userspace segfaults and make it runtime
configurable via the /proc/sys/debug/exception-trace variable. This
should resolve syslog from growing way too fast and thus prevents
possible system service attacks.
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org # 3.13+
Checkin:
b3b42ac2cb x86-64, modify_ldt: Ban 16-bit segments on 64-bit kernels
disabled 16-bit segments on 64-bit kernels due to an information
leak. However, it does seem that people are genuinely using Wine to
run old 16-bit Windows programs on Linux.
A proper fix for this ("espfix64") is coming in the upcoming merge
window, but as a temporary fix, create a sysctl to allow the
administrator to re-enable support for 16-bit segments.
It adds a "/proc/sys/abi/ldt16" sysctl that defaults to zero (off). If
you hit this issue and care about your old Windows program more than
you care about a kernel stack address information leak, you can do
echo 1 > /proc/sys/abi/ldt16
as root (add it to your startup scripts), and you should be ok.
The sysctl table is only added if you have COMPAT support enabled on
x86-64, but I assume anybody who runs old windows binaries very much
does that ;)
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Link: http://lkml.kernel.org/r/CA%2B55aFw9BPoD10U1LfHbOMpHWZkvJTkMcfCs9s3urPr1YyWBxw@mail.gmail.com
Cc: <stable@vger.kernel.org>
Meta overrode _STK_LIM_MAX (the default RLIMIT_STACK hard limit) to
256MB, apparently in an attempt to prevent setup_arg_pages's
STACK_GROWSUP code from choosing the maximum stack size of 1GB, which is
far too large for Meta's limited virtual address space and hits a BUG_ON
(stack_top is usually 0x3ffff000).
However the commit "metag: Reduce maximum stack size to 256MB" reduces
the absolute stack size limit to a safe value for metag. This allows the
default _STK_LIM_MAX override to be removed, bringing the default
behaviour in line with all other architectures. Parisc in particular
recently removed their override of _STK_LIMT_MAX in commit e0d8898d76
(parisc: remove _STK_LIM_MAX override) since it subtly affects stack
allocation semantics in userland. Meta's uapi/asm/resource.h can now be
removed and switch to using generic-y.
Suggested-by: Helge Deller <deller@gmx.de>
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-metag@vger.kernel.org
Cc: John David Anglin <dave.anglin@bell.net>
This patch affects only architectures where the stack grows upwards
(currently parisc and metag only). On those do not hardcode the maximum
initial stack size to 1GB for 32-bit processes, but make it configurable
via a config option.
The main problem with the hardcoded stack size is, that we have two
memory regions which grow upwards: stack and heap. To keep most of the
memory available for heap in a flexmap memory layout, it makes no sense
to hard allocate up to 1GB of the memory for stack which can't be used
as heap then.
This patch makes the stack size for 32-bit processes configurable and
uses 80MB as default value which has been in use during the last few
years on parisc and which hasn't showed any problems yet.
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: linux-parisc@vger.kernel.org
Cc: linux-metag@vger.kernel.org
Cc: John David Anglin <dave.anglin@bell.net>
Specify the maximum stack size for arches where the stack grows upward
(parisc and metag) in asm/processor.h rather than hard coding in
fs/exec.c so that metag can specify a smaller value of 256MB rather than
1GB.
This fixes a BUG on metag if the RLIMIT_STACK hard limit is increased
beyond a safe value by root. E.g. when starting a process after running
"ulimit -H -s unlimited" it will then attempt to use a stack size of the
maximum 1GB which is far too big for metag's limited user virtual
address space (stack_top is usually 0x3ffff000):
BUG: failure at fs/exec.c:589/shift_arg_pages()!
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: linux-parisc@vger.kernel.org
Cc: linux-metag@vger.kernel.org
Cc: John David Anglin <dave.anglin@bell.net>
Cc: stable@vger.kernel.org # only needed for >= v3.9 (arch/metag)
Volatile access doesn't really imply the compiler barrier. Volatile access
is only ordered with respect to other volatile accesses, it isn't ordered
with respect to general memory accesses. Gcc may reorder memory accesses
around volatile access, as we can see in this simple example (if we
compile it with optimization, both increments of *b will be collapsed to
just one):
void fn(volatile int *a, long *b)
{
(*b)++;
*a = 10;
(*b)++;
}
Consequently, we need the compiler barrier after a write to the volatile
variable, to make sure that the compiler doesn't reorder the volatile
write with something else.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org
Acked-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Linus Torvalds
Miklos Szeredi
Mark Salter
Leif Lindholm
John David Anglin
Helge Deller
James Hogan
Mikulas Patocka
Steven J. Hill
Markos Chandras