This patch allows "dynamic ftrace" if CONFIG_DYNAMIC_FTRACE is enabled.
Here we can turn on and off tracing dynamically per-function base.
On arm64, this is done by patching single branch instruction to _mcount()
inserted by gcc -pg option. The branch is replaced to NOP initially at
kernel start up, and later on, NOP to branch to ftrace_caller() when
enabled or branch to NOP when disabled.
Please note that ftrace_caller() is a counterpart of _mcount() in case of
'static' ftrace.
More details on architecture specific requirements are described in
Documentation/trace/ftrace-design.txt.
Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
This patch implements arm64 specific part to support function tracers,
such as function (CONFIG_FUNCTION_TRACER), function_graph
(CONFIG_FUNCTION_GRAPH_TRACER) and function profiler
(CONFIG_FUNCTION_PROFILER).
With 'function' tracer, all the functions in the kernel are traced with
timestamps in ${sysfs}/tracing/trace. If function_graph tracer is
specified, call graph is generated.
The kernel must be compiled with -pg option so that _mcount() is inserted
at the beginning of functions. This function is called on every function's
entry as long as tracing is enabled.
In addition, function_graph tracer also needs to be able to probe function's
exit. ftrace_graph_caller() & return_to_handler do this by faking link
register's value to intercept function's return path.
More details on architecture specific requirements are described in
Documentation/trace/ftrace-design.txt.
Reviewed-by: Ganapatrao Kulkarni <ganapatrao.kulkarni@cavium.com> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
Recordmcount utility under scripts is run, after compiling each object,
to find out all the locations of calling _mcount() and put them into
specific seciton named __mcount_loc.
Then linker collects all such information into a table in the kernel image
(between __start_mcount_loc and __stop_mcount_loc) for later use by ftrace.
This patch adds arm64 specific definitions to identify such locations.
There are two types of implementation, C and Perl. On arm64, only C version
is used to build the kernel now that CONFIG_HAVE_C_RECORDMCOUNT is on.
But Perl version is also maintained.
This patch also contains a workaround just in case where a header file,
elf.h, on host machine doesn't have definitions of EM_AARCH64 nor
R_AARCH64_ABS64. Without them, compiling C version of recordmcount will
fail.
Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
Geoff Levand [Fri, 16 May 2014 17:26:01 +0000 (18:26 +0100)]
arm64: Fix linker script entry point
Change the arm64 linker script ENTRY() command to define _text as the
kernel entry point.
The arm64 boot protocol specifies that the kernel must be entered at the
beginning of the kernel image. The existing ENTRY() command defined the
symbol stext as the entry point, which emitted an incorrect entry point,
but would not cause a runtime error because the existing entry code
immediately jumps to stext.
Will Deacon [Thu, 22 May 2014 14:13:05 +0000 (15:13 +0100)]
arm64: defconfig: enable a few more common/useful options in defconfig
Whilst our defconfig is certainly usable, there are a few extra features
we can enable to make it considerably more useful, particularly if
people are using it for testing:
- KVM
- SWAP
- Hugepages
- ARMv8 crypto
This patch enables these options in our defconfig. Note that the ordering
has changed slightly, since this is the result of a new savedefconfig
make target.
Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
AKASHI Takahiro [Tue, 20 May 2014 11:31:04 +0000 (20:31 +0900)]
ftrace: Make CALLER_ADDRx macros more generic
Most archs with HAVE_ARCH_CALLER_ADDR have pretty much the same
definitions of CALLER_ADDRx(n). Instead of duplicating the code for all
the archs, define a ftrace_return_address0() and
ftrace_return_address(n) that can be overwritten by the archs if they
need to do something different. Instead of 7 macros in every arch, we
now only have at most 2 (and actually only 1 as
ftrace_return_address0() should be the same for all archs).
The CALLER_ADDRx(n) will now be defined in linux/ftrace.h and use the
ftrace_return_address*(n?) macros. This removes a lot of the duplicate
code.
Arun KS [Wed, 7 May 2014 01:41:23 +0000 (02:41 +0100)]
arm64: Fix deadlock scenario with smp_send_stop()
If one process calls sys_reboot and that process then stops other
CPUs while those CPUs are within a spin_lock() region we can
potentially encounter a deadlock scenario like below.
CPU 0 CPU 1
----- -----
spin_lock(my_lock)
smp_send_stop()
<send IPI> handle_IPI()
disable_preemption/irqs
while(1);
<PREEMPT>
spin_lock(my_lock) <--- Waits forever
We shouldn't attempt to run any other tasks after we send a stop
IPI to a CPU so disable preemption so that this task runs to
completion. We use local_irq_disable() here for cross-arch
consistency with x86.
Arun KS [Wed, 7 May 2014 01:41:22 +0000 (02:41 +0100)]
arm64: Fix machine_shutdown() definition
This patch ports most of commit 19ab428f4b79 "ARM: 7759/1: decouple CPU
offlining from reboot/shutdown" by Stephen Warren from arch/arm to
arch/arm64.
machine_shutdown() is a hook for kexec. Add a comment saying so, since
it isn't obvious from the function name.
Halt, power-off, and restart have different requirements re: stopping
secondary CPUs than kexec has. The former simply require the secondary
CPUs to be quiesced somehow, whereas kexec requires them to be
completely non-operational, so that no matter where the kexec target
images are written in RAM, they won't influence operation of the
secondary CPUS,which could happen if the CPUs were still executing some
kind of pin loop. To this end, modify machine_halt, power_off, and
restart to call smp_send_stop() directly, rather than calling
machine_shutdown().
In machine_shutdown(), replace the call to smp_send_stop() with a call
to disable_nonboot_cpus(). This completely disables all but one CPU,
thus satisfying the kexec requirements a couple paragraphs above.
ARM: 7872/1: Support arch_irq_work_raise() via self IPIs
By default, IRQ work is run from the tick interrupt (see
irq_work_run() in update_process_times()). When we're in full
NOHZ mode, restarting the tick requires the use of IRQ work and
if the only place we run IRQ work is in the tick interrupt we
have an unbreakable cycle. Implement arch_irq_work_raise() via
self IPIs to break this cycle and get the tick started again.
Note that we implement this via IPIs which are only available on
SMP builds. This shouldn't be a problem because full NOHZ is only
supported on SMP builds anyway.
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Reviewed-by: Kevin Hilman <khilman@linaro.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Larry Bassel <larry.bassel@linaro.org> Reviewed-by: Kevin Hilman <khilman@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Mark Brown [Fri, 2 May 2014 20:38:29 +0000 (21:38 +0100)]
arm64: topology: Add support for topology DT bindings
Add support for parsing the explicit topology bindings to discover the
topology of the system.
Since it is not currently clear how to map multi-level clusters for the
scheduler all leaf clusters are presented to the scheduler at the same
level. This should be enough to provide good support for current systems.
Signed-off-by: Mark Brown <broonie@linaro.org> Reviewed-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Mark Brown [Fri, 2 May 2014 20:38:28 +0000 (21:38 +0100)]
arm64: topology: Initialise default topology state immediately
As a legacy of the way 32 bit ARM did things the topology code uses a null
topology map by default and then overwrites it by mapping cores with no
information to a cluster by themselves later. In order to make it simpler
to reset things as part of recovering from parse failures in firmware
information directly set this configuration on init. A core will always be
its own sibling so there should be no risk of confusion with firmware
provided information.
Signed-off-by: Mark Brown <broonie@linaro.org> Reviewed-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Zi Shen Lim [Fri, 2 May 2014 20:38:27 +0000 (21:38 +0100)]
arm64: sched: Remove unused mc_capable() and smt_capable()
Remove unused and deprecated mc_capable() and smt_capable().
Both were added recently by f6e763b93a6c ("arm64: topology:
Implement basic CPU topology support"). Uses of both were removed
by 8e7fbcbc22c1 ("sched: Remove stale power aware scheduling
remnants and dysfunctional knobs").
Signed-off-by: Zi Shen Lim <zlim@broadcom.com> Signed-off-by: Mark Brown <broonie@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
While the aim is increased security for --x memory maps, it does not
protect against kernel level reads. Until SECCOMP is implemented for
arm64, revert this patch to avoid giving a false idea of execute-only
mappings.
Catalin Marinas [Fri, 16 May 2014 09:05:11 +0000 (10:05 +0100)]
Merge tag 'for-3.16' of git://git.linaro.org/people/ard.biesheuvel/linux-arm into upstream
FPSIMD register bank context switching and crypto algorithms
optimisations for arm64 from Ard Biesheuvel.
* tag 'for-3.16' of git://git.linaro.org/people/ard.biesheuvel/linux-arm:
arm64/crypto: AES-ECB/CBC/CTR/XTS using ARMv8 NEON and Crypto Extensions
arm64: pull in <asm/simd.h> from asm-generic
arm64/crypto: AES in CCM mode using ARMv8 Crypto Extensions
arm64/crypto: AES using ARMv8 Crypto Extensions
arm64/crypto: GHASH secure hash using ARMv8 Crypto Extensions
arm64/crypto: SHA-224/SHA-256 using ARMv8 Crypto Extensions
arm64/crypto: SHA-1 using ARMv8 Crypto Extensions
arm64: add support for kernel mode NEON in interrupt context
arm64: defer reloading a task's FPSIMD state to userland resume
arm64: add abstractions for FPSIMD state manipulation
asm-generic: allow generic unaligned access if the arch supports it
Ard Biesheuvel [Fri, 21 Mar 2014 09:19:17 +0000 (10:19 +0100)]
arm64/crypto: AES-ECB/CBC/CTR/XTS using ARMv8 NEON and Crypto Extensions
This adds ARMv8 implementations of AES in ECB, CBC, CTR and XTS modes,
both for ARMv8 with Crypto Extensions and for plain ARMv8 NEON.
The Crypto Extensions version can only run on ARMv8 implementations that
have support for these optional extensions.
The plain NEON version is a table based yet time invariant implementation.
All S-box substitutions are performed in parallel, leveraging the wide range
of ARMv8's tbl/tbx instructions, and the huge NEON register file, which can
comfortably hold the entire S-box and still have room to spare for doing the
actual computations.
The key expansion routines were borrowed from aes_generic.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Ard Biesheuvel [Wed, 26 Mar 2014 19:53:05 +0000 (20:53 +0100)]
arm64/crypto: GHASH secure hash using ARMv8 Crypto Extensions
This is a port to ARMv8 (Crypto Extensions) of the Intel implementation of the
GHASH Secure Hash (used in the Galois/Counter chaining mode). It relies on the
optional PMULL/PMULL2 instruction (polynomial multiply long, what Intel call
carry-less multiply).
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Ard Biesheuvel [Thu, 20 Mar 2014 14:35:40 +0000 (15:35 +0100)]
arm64/crypto: SHA-224/SHA-256 using ARMv8 Crypto Extensions
This patch adds support for the SHA-224 and SHA-256 Secure Hash Algorithms
for CPUs that have support for the SHA-2 part of the ARM v8 Crypto Extensions.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
arm64: is_compat_task is defined both in asm/compat.h and linux/compat.h
Some kernel files may include both linux/compat.h and asm/compat.h directly
or indirectly. Since both header files contain is_compat_task() under
!CONFIG_COMPAT, compiling them with !CONFIG_COMPAT will eventually fail.
Such files include kernel/auditsc.c, kernel/seccomp.c and init/do_mountfs.c
(do_mountfs.c may read asm/compat.h via asm/ftrace.h once ftrace is
implemented).
So this patch proactively
1) removes is_compat_task() under !CONFIG_COMPAT from asm/compat.h
2) replaces asm/compat.h to linux/compat.h in kernel/*.c,
but asm/compat.h is still necessary in ptrace.c and process.c because
they use is_compat_thread().
Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
arm64: split syscall_trace() into separate functions for enter/exit
As done in arm, this change makes it easy to confirm we invoke syscall
related hooks, including syscall tracepoint, audit and seccomp which would
be implemented later, in correct order. That is, undoing operations in the
opposite order on exit that they were done on entry.
Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
arm64: make a single hook to syscall_trace() for all syscall features
Currently syscall_trace() is called only for ptrace.
With additional TIF_xx flags defined, it is now called in all the cases
of audit, ftrace and seccomp in addition to ptrace.
Acked-by: Richard Guy Briggs <rgb@redhat.com> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Will Deacon [Tue, 29 Apr 2014 18:04:06 +0000 (19:04 +0100)]
arm64: debug: avoid accessing mdscr_el1 on fault paths where possible
Since mdscr_el1 is part of the debug register group, it is highly likely
to be trapped by a hypervisor to prevent virtual machines from debugging
(buggering?) each other. Unfortunately, this absolutely destroys our
performance, since we access the register on many of our low-level
fault handling paths to keep track of the various debug state machines.
This patch removes our dependency on mdscr_el1 in the case that debugging
is not being used. More specifically we:
- Use TIF_SINGLESTEP to indicate that a task is stepping at EL0 and
avoid disabling step in the MDSCR when we don't need to.
MDSCR_EL1.SS handling is moved to kernel_entry, when trapping from
userspace.
- Ensure debug exceptions are re-enabled on *all* exception entry
paths, even the debug exception handling path (where we re-enable
exceptions after invoking the handler). Since we can now rely on
MDSCR_EL1.SS being cleared by the entry code, exception handlers can
usually enable debug immediately before enabling interrupts.
- Remove all debug exception unmasking from ret_to_user and
el1_preempt, since we will never get here with debug exceptions
masked.
This results in a slight change to kernel debug behaviour, where we now
step into interrupt handlers and data aborts from EL1 when debugging the
kernel, which is actually a useful thing to do. A side-effect of this is
that it *does* potentially prevent stepping off {break,watch}points when
there is a high-frequency interrupt source (e.g. a timer), so a debugger
would need to use either breakpoints or manually disable interrupts to
get around this issue.
With this patch applied, guest performance is restored under KVM when
debug register accesses are trapped (and we get a measurable performance
increase on the host on Cortex-A57 too).
Cc: Ian Campbell <ian.campbell@citrix.com> Tested-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Linus Torvalds [Fri, 9 May 2014 19:24:20 +0000 (12:24 -0700)]
Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Peter Anvin:
"A somewhat unpleasantly large collection of small fixes. The big ones
are the __visible tree sweep and a fix for 'earlyprintk=efi,keep'. It
was using __init functions with predictably suboptimal results.
Another key fix is a build fix which would produce output that simply
would not decompress correctly in some configuration, due to the
existing Makefiles picking up an unfortunate local label and mistaking
it for the global symbol _end.
Additional fixes include the handling of 64-bit numbers when setting
the vdso data page (a latent bug which became manifest when i386
started exporting a vdso with time functions), a fix to the new MSR
manipulation accessors which would cause features to not get properly
unblocked, a build fix for 32-bit userland, and a few new platform
quirks"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, vdso, time: Cast tv_nsec to u64 for proper shifting in update_vsyscall()
x86: Fix typo in MSR_IA32_MISC_ENABLE_LIMIT_CPUID macro
x86: Fix typo preventing msr_set/clear_bit from having an effect
x86/intel: Add quirk to disable HPET for the Baytrail platform
x86/hpet: Make boot_hpet_disable extern
x86-64, build: Fix stack protector Makefile breakage with 32-bit userland
x86/reboot: Add reboot quirk for Certec BPC600
asmlinkage: Add explicit __visible to drivers/*, lib/*, kernel/*
asmlinkage, x86: Add explicit __visible to arch/x86/*
asmlinkage: Revert "lto: Make asmlinkage __visible"
x86, build: Don't get confused by local symbols
x86/efi: earlyprintk=efi,keep fix
Will Deacon [Fri, 2 May 2014 15:24:15 +0000 (16:24 +0100)]
arm64: mm: use inner-shareable barriers for inner-shareable maintenance
In order to ensure ordering and completion of inner-shareable maintenance
instructions (cache and TLB) on AArch64, we can use the -ish suffix to
the dmb and dsb instructions respectively.
This patch updates our low-level cache and tlb maintenance routines to
use the inner-shareable barrier variants where appropriate.
Will Deacon [Fri, 2 May 2014 15:24:14 +0000 (16:24 +0100)]
arm64: kvm: use inner-shareable barriers for inner-shareable maintenance
In order to ensure completion of inner-shareable maintenance instructions
(cache and TLB) on AArch64, we can use the -ish suffix to the dsb
instruction.
This patch relaxes our dsb sy instructions to dsb ish where possible.
Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Will Deacon [Fri, 2 May 2014 15:24:13 +0000 (16:24 +0100)]
arm64: head: fix cache flushing and barriers in set_cpu_boot_mode_flag
set_cpu_boot_mode_flag is used to identify which exception levels are
encountered across the system by CPUs trying to enter the kernel. The
basic algorithm is: if a CPU is booting at EL2, it will set a flag at
an offset of #4 from __boot_cpu_mode, a cacheline-aligned variable.
Otherwise, a flag is set at an offset of zero into the same cacheline.
This enables us to check that all CPUs booted at the same exception
level.
This cacheline is written with the stage-1 MMU off (that is, via a
strongly-ordered mapping) and will bypass any clean lines in the cache,
leading to potential coherence problems when the variable is later
checked via the normal, cacheable mapping of the kernel image.
This patch reworks the broken flushing code so that we:
(1) Use a DMB to order the strongly-ordered write of the cacheline
against the subsequent cache-maintenance operation (by-VA
operations only hazard against normal, cacheable accesses).
(2) Use a single dc ivac instruction to invalidate any clean lines
containing a stale copy of the line after it has been updated.
Will Deacon [Fri, 2 May 2014 15:24:12 +0000 (16:24 +0100)]
arm64: barriers: use barrier() instead of smp_mb() when !SMP
The recently introduced acquire/release accessors refer to smp_mb()
in the !CONFIG_SMP case. This is confusing when reading the code, so use
barrier() directly when we know we're UP.
Will Deacon [Fri, 2 May 2014 15:24:10 +0000 (16:24 +0100)]
arm64: barriers: make use of barrier options with explicit barriers
When calling our low-level barrier macros directly, we can often suffice
with more relaxed behaviour than the default "all accesses, full system"
option.
This patch updates the users of dsb() to specify the option which they
actually require.
Steve Capper [Fri, 2 May 2014 13:49:00 +0000 (14:49 +0100)]
arm64: mm: Optimise tlb flush logic where we have >4K granule
The tlb maintainence functions: __cpu_flush_user_tlb_range and
__cpu_flush_kern_tlb_range do not take into consideration the page
granule when looping through the address range, and repeatedly flush
tlb entries for the same page when operating with 64K pages.
This patch re-works the logic s.t. we instead advance the loop by
1 << (PAGE_SHIFT - 12), so avoid repeating ourselves.
Also the routines have been converted from assembler to static inline
functions to aid with legibility and potential compiler optimisations.
The isb() has been removed from flush_tlb_kernel_range(.) as it is
only needed when changing the execute permission of a mapping. If one
needs to set an area of the kernel as execute/non-execute an isb()
must be inserted after the call to flush_tlb_kernel_range.
Cc: Laura Abbott <lauraa@codeaurora.org> Signed-off-by: Steve Capper <steve.capper@linaro.org> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Will Deacon [Wed, 30 Apr 2014 15:23:06 +0000 (16:23 +0100)]
arm64: xchg: prevent warning if return value is unused
Some users of xchg() don't bother using the return value, which results
in a compiler warning like the following (from kgdb):
In file included from linux/arch/arm64/include/asm/atomic.h:27:0,
from include/linux/atomic.h:4,
from include/linux/spinlock.h:402,
from include/linux/seqlock.h:35,
from include/linux/time.h:5,
from include/uapi/linux/timex.h:56,
from include/linux/timex.h:56,
from include/linux/sched.h:19,
from include/linux/pid_namespace.h:4,
from kernel/debug/debug_core.c:30:
kernel/debug/debug_core.c: In function ‘kgdb_cpu_enter’:
linux/arch/arm64/include/asm/cmpxchg.h:75:3: warning: value computed is not used [-Wunused-value]
((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr))))
^
linux/arch/arm64/include/asm/atomic.h:132:30: note: in expansion of macro ‘xchg’
#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
kernel/debug/debug_core.c:504:4: note: in expansion of macro ‘atomic_xchg’
atomic_xchg(&kgdb_active, cpu);
^
This patch makes use of the same trick as we do for cmpxchg, by assigning
the return value to a dummy variable in the xchg() macro itself.
Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Boris Ostrovsky [Fri, 9 May 2014 15:11:27 +0000 (11:11 -0400)]
x86, vdso, time: Cast tv_nsec to u64 for proper shifting in update_vsyscall()
With tk->wall_to_monotonic.tv_nsec being a 32-bit value on 32-bit
systems, (tk->wall_to_monotonic.tv_nsec << tk->shift) in update_vsyscall()
may lose upper bits or, worse, add them since compiler will do this:
(u64)(tk->wall_to_monotonic.tv_nsec << tk->shift)
instead of
((u64)tk->wall_to_monotonic.tv_nsec << tk->shift)
So if, for example, tv_nsec is 0x800000 and shift is 8 we will end up
with 0xffffffff80000000 instead of 0x80000000. And then we are stuck in
the subsequent 'while' loop.
Andres Freund [Fri, 9 May 2014 01:29:16 +0000 (03:29 +0200)]
x86: Fix typo preventing msr_set/clear_bit from having an effect
Due to a typo the msr accessor function introduced in 22085a66c2fab6cf9b9393c056a3600a6b4735de didn't have any lasting
effects because they accidentally wrote the old value back.
After c0a639ad0bc6b178b46996bd1f821a04643e2bde this at the very least
this causes cpuid limits not to be lifted on some cpus leading to
missing capabilities for those.
Steve Capper [Tue, 6 May 2014 13:02:27 +0000 (14:02 +0100)]
arm64: mm: Create gigabyte kernel logical mappings where possible
We have the capability to map 1GB level 1 blocks when using a 4K
granule.
This patch adjusts the create_mapping logic s.t. when mapping physical
memory on boot, we attempt to use a 1GB block if both the VA and PA
start and end are 1GB aligned. This both reduces the levels of lookup
required to resolve a kernel logical address, as well as reduces TLB
pressure on cores that support 1GB TLB entries.
Signed-off-by: Steve Capper <steve.capper@linaro.org> Tested-by: Jungseok Lee <jays.lee@samsung.com>
[catalin.marinas@arm.com: s/prot_sect_kernel/PROT_SECT_NORMAL_EXEC/] Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Bjorn Helgaas [Thu, 8 May 2014 21:13:47 +0000 (22:13 +0100)]
arm64: Make atomic64_t() return "long", not "long long"
arm64 sets CONFIG_64BIT=y and hence uses the "long counter" atomic64_t
definition from include/linux/types.h. Make atomic64_read() return "long",
not "long long".
The primary aim of this patchset is to remove the pgprot_default and
prot_sect_default global variables and rely strictly on predefined
values. The original goal was to be able to run SMP kernels on UP
hardware by not setting the Shareability bit. However, it is unlikely to
see UP ARMv8 hardware and even if we do, the Shareability bit is no
longer assumed to disable cacheable accesses.
A side effect is that the device mappings now have the Shareability
attribute set. The hardware, however, should ignore it since Device
accesses are always Outer Shareable.
Following the removal of the two global variables, there is some PROT_*
macro reshuffling and cleanup, including the __PAGE_* macros (replaced
by PAGE_*).
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Will Deacon <will.deacon@arm.com>
The ARMv8 architecture allows execute-only user permissions by clearing
the PTE_UXN and PTE_USER bits. The kernel, however, can still access
such page, so execute-only page permission does not protect against
read(2)/write(2) etc. accesses. Systems requiring such protection must
implement/enable features like SECCOMP.
This patch changes the arm64 __P100 and __S100 protection_map[] macros
to the new __PAGE_EXECONLY attributes. A side effect is that
pte_valid_user() no longer triggers for __PAGE_EXECONLY since PTE_USER
isn't set. To work around this, the check is done on the PTE_NG bit via
the pte_valid_ng() macro. VM_READ is also checked now for page faults.
arm64: Expose ESR_EL1 information to user when SIGSEGV/SIGBUS
This information is useful for instruction emulators to detect
read/write and access size without having to decode the faulting
instruction. The current patch exports it via sigcontext (struct
esr_context) and is only valid for SIGSEGV and SIGBUS.
This patch removes the aux_context structure (and the containing file)
to allow the placement of the _aarch64_ctx end magic based on the
context stored on the signal stack.
arm64: Provide read/write fault information in compat signal handlers
For AArch32, bit 11 (WnR) of the FSR/ESR register is set when the fault
was caused by a write access and applications like Qemu rely on such
information being provided in sigcontext. This patch introduces the
ESR_EL1 tracking for the arm64 kernel faults and sets bit 11 accordingly
in compat sigcontext.
arm64: Remove boot thread synchronisation for spin-table release method
The synchronisation with the boot thread already happens in __cpu_up()
via wait_for_completion_timeout(). In addition, __cpu_up() calls are
protected by the cpu_add_remove_lock mutex and already serialised.
arm64: Implement cache_line_size() based on CTR_EL0.CWG
The hardware provides the maximum cache line size in the system via the
CTR_EL0.CWG bits. This patch implements the cache_line_size() function
to read such information, together with a sanity check if the statically
defined L1_CACHE_BYTES is smaller than the hardware value.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Will Deacon <will.deacon@arm.com>
Linus Torvalds [Fri, 9 May 2014 02:20:45 +0000 (19:20 -0700)]
Merge tag 'xfs-for-linus-3.15-rc5' of git://oss.sgi.com/xfs/xfs
Pull xfs fixes from Dave Chinner:
"The main fix is adding support for default ACLs on O_TMPFILE opened
inodes to bring XFS into line with other filesystems. Metadata CRCs
are now also considered well enough tested to be fully supported, so
we're removing the shouty warnings issued at mount time for
filesystems with that format. And there's transaction block
reservation overrun fix.
Summary:
- fix a remote attribute size calculation bug that leads to a
transaction overrun
- add default ACLs to O_TMPFILE files
- Remove the EXPERIMENTAL tag from filesystems with metadata CRC
support"
* tag 'xfs-for-linus-3.15-rc5' of git://oss.sgi.com/xfs/xfs:
xfs: remote attribute overwrite causes transaction overrun
xfs: initialize default acls for ->tmpfile()
xfs: fully support v5 format filesystems
Linus Torvalds [Thu, 8 May 2014 21:17:13 +0000 (14:17 -0700)]
Merge tag 'trace-fixes-v3.15-rc4-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fixes from Steven Rostedt:
"This contains two fixes.
The first is a long standing bug that causes bogus data to show up in
the refcnt field of the module_refcnt tracepoint. It was introduced
by a merge conflict resolution back in 2.6.35-rc days.
The result should be 'refcnt = incs - decs', but instead it did
'refcnt = incs + decs'.
The second fix is to a bug that was introduced in this merge window
that allowed for a tracepoint funcs pointer to be used after it was
freed. Moving the location of where the probes are released solved
the problem"
* tag 'trace-fixes-v3.15-rc4-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracepoint: Fix use of tracepoint funcs after rcu free
trace: module: Maintain a valid user count
Linus Torvalds [Thu, 8 May 2014 21:06:45 +0000 (14:06 -0700)]
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
Pull input subsystem fixes from Dmitry Torokhov:
"Just a few fixups to various drivers"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
Input: elantech - fix touchpad initialization on Gigabyte U2442
Input: tca8418 - fix loading this driver as a module from a device tree
Input: bma150 - extend chip detection for bma180
Input: atkbd - fix keyboard not working on some LG laptops
Input: synaptics - add min/max quirk for ThinkPad Edge E431
Linus Torvalds [Thu, 8 May 2014 20:51:53 +0000 (13:51 -0700)]
Merge tag 'sound-3.15-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound
Pull sound fixes from Takashi Iwai:
"A bunch of small fixes for USB-audio and HD-audio, where most of them
are for regressions: USB-audio PM fixes, ratelimit annoyance fix, HDMI
offline state fix, and a couple of device-specific quirks"
* tag 'sound-3.15-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
ALSA: hda - hdmi: Set converter channel count even without sink
ALSA: usb-audio: work around corrupted TEAC UD-H01 feedback data
ALSA: usb-audio: Fix deadlocks at resuming
ALSA: usb-audio: Save mixer status only once at suspend
ALSA: usb-audio: Prevent printk ratelimiting from spamming kernel log while DEBUG not defined
ALSA: hda - add headset mic detect quirk for a Dell laptop
Linus Torvalds [Thu, 8 May 2014 19:41:14 +0000 (12:41 -0700)]
Merge tag 'mfd-mmc-fixes-3.15-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd
Pull mmc/rtsx revert from Lee Jones.
* tag 'mfd-mmc-fixes-3.15-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd:
mmc: rtsx: Revert "mmc: rtsx: add support for pre_req and post_req"
tracepoint: Fix use of tracepoint funcs after rcu free
Commit de7b2973903c "tracepoint: Use struct pointer instead of name hash
for reg/unreg tracepoints" introduces a use after free by calling
release_probes on the old struct tracepoint array before the newly
allocated array is published with rcu_assign_pointer. There is a race
window where tracepoints (RCU readers) can perform a
"use-after-grace-period-after-free", which shows up as a GPF in
stress-tests.
Romain Izard [Tue, 4 Mar 2014 09:09:39 +0000 (10:09 +0100)]
trace: module: Maintain a valid user count
The replacement of the 'count' variable by two variables 'incs' and
'decs' to resolve some race conditions during module unloading was done
in parallel with some cleanup in the trace subsystem, and was integrated
as a merge.
Unfortunately, the formula for this replacement was wrong in the tracing
code, and the refcount in the traces was not usable as a result.
Use 'count = incs - decs' to compute the user count.
Ard Biesheuvel [Mon, 24 Feb 2014 14:26:29 +0000 (15:26 +0100)]
arm64: add support for kernel mode NEON in interrupt context
This patch modifies kernel_neon_begin() and kernel_neon_end(), so
they may be called from any context. To address the case where only
a couple of registers are needed, kernel_neon_begin_partial(u32) is
introduced which takes as a parameter the number of bottom 'n' NEON
q-registers required. To mark the end of such a partial section, the
regular kernel_neon_end() should be used.
Ard Biesheuvel [Thu, 8 May 2014 09:20:23 +0000 (11:20 +0200)]
arm64: defer reloading a task's FPSIMD state to userland resume
If a task gets scheduled out and back in again and nothing has touched
its FPSIMD state in the mean time, there is really no reason to reload
it from memory. Similarly, repeated calls to kernel_neon_begin() and
kernel_neon_end() will preserve and restore the FPSIMD state every time.
This patch defers the FPSIMD state restore to the last possible moment,
i.e., right before the task returns to userland. If a task does not return to
userland at all (for any reason), the existing FPSIMD state is preserved
and may be reused by the owning task if it gets scheduled in again on the
same CPU.
This patch adds two more functions to abstract away from straight FPSIMD
register file saves and restores:
- fpsimd_restore_current_state -> ensure current's FPSIMD state is loaded
- fpsimd_flush_task_state -> invalidate live copies of a task's FPSIMD state
Ard Biesheuvel [Mon, 24 Feb 2014 14:26:27 +0000 (15:26 +0100)]
arm64: add abstractions for FPSIMD state manipulation
There are two tacit assumptions in the FPSIMD handling code that will no longer
hold after the next patch that optimizes away some FPSIMD state restores:
. the FPSIMD registers of this CPU contain the userland FPSIMD state of
task 'current';
. when switching to a task, its FPSIMD state will always be restored from
memory.
This patch adds the following functions to abstract away from straight FPSIMD
register file saves and restores:
- fpsimd_preserve_current_state -> ensure current's FPSIMD state is saved
- fpsimd_update_current_state -> replace current's FPSIMD state
Where necessary, the signal handling and fork code are updated to use the above
wrappers instead of poking into the FPSIMD registers directly.
commit <mmc: rtsx: add support for pre_req and post_req> did use
mutex_unlock() in tasklet, but mutex_unlock() can't be used in
tasklet(atomic context). The driver needs to use mutex to avoid
concurrency, so we can't use tasklet here, the patch need to be
removed.
The spinlock host->lock and pcr->lock may deadlock, one way to solve
the deadlock is remove host->lock in sd_isr_done_transfer(), but if
using workqueue the we can avoid using the spinlock and also avoid
the problem.
Signed-off-by: Micky Ching <micky_ching@realsil.com.cn> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Lee Jones <lee.jones@linaro.org>
HPET on some platform has accuracy problem. Making
"boot_hpet_disable" extern so that we can runtime disable
the HPET timer by using quirk to check the platform.
Linus Torvalds [Wed, 7 May 2014 23:07:58 +0000 (16:07 -0700)]
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid
Pull HID fixes from Jiri Kosina:
- fix a small bug in computation of report size, which might cause some
devices (Atmel touchpad found on the Samsung Ativ 9) to reject
reports with otherwise valid contents
- a few device-ID specific quirks/additions piggy-backing on top of it
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid:
HID: sensor-hub: Add in quirk for sensor hub in Lenovo Ideapad Yogas
HID: add NO_INIT_REPORTS quirk for Synaptics Touch Pad V 103S
HID: core: fix computation of the report size
HID: multitouch: add support of EliteGroup 05D8 panels
Linus Torvalds [Wed, 7 May 2014 22:47:47 +0000 (15:47 -0700)]
Merge branch 'drm-radeon-mullins' of git://people.freedesktop.org/~airlied/linux
Pull radeon mullins support from Dave Airlie:
"This is support for the new AMD mullins APU, it pretty much just adds
support to the driver in the all the right places, and is pretty low
risk wrt other GPUs"
Oh well. I guess it ends up fitting under "support new hardware" for
merging late.
* 'drm-radeon-mullins' of git://people.freedesktop.org/~airlied/linux:
drm/radeon: add pci ids for Mullins
drm/radeon: add Mullins VCE support
drm/radeon: modesetting updates for Mullins.
drm/radeon: dpm updates for KV/KB
drm/radeon: add Mullins dpm support.
drm/radeon: add Mullins UVD support.
drm/radeon: update cik init for Mullins.
drm/radeon: add Mullins chip family
Linus Torvalds [Wed, 7 May 2014 22:45:13 +0000 (15:45 -0700)]
Merge branch 'drm-fixes' of git://people.freedesktop.org/~airlied/linux
Pull drm fixes from Dave Airlie:
"radeon, i915 and nouveau fixes, all fixes for regressions or black
screens, or possible oopses"
* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
drm/radeon: lower the ref * post PLL maximum
drm/radeon: check that we have a clock before PLL setup
drm/radeon: drm/radeon: add missing radeon_semaphore_free to error path
drm/radeon: Fix num_banks calculation for SI
agp: info leak in agpioc_info_wrap()
drm/gm107/gr: bump attrib cb size quite a bit
drm/nouveau: fix another lock unbalance in nouveau_crtc_page_flip
drm/nouveau/bios: fix shadowing from PROM on big-endian systems
drm/nouveau/acpi: allow non-optimus setups to load vbios from acpi
drm/radeon/dp: check for errors in dpcd reads
drm/radeon: avoid high jitter with small frac divs
drm/radeon: check buffer relocation offset
drm/radeon: use pflip irq on R600+ v2
drm/radeon/uvd: use lower clocks on old UVD to boot v2
drm/i915: don't try DP_LINK_BW_5_4 on HSW ULX
drm/i915: Sanitize the enable_ppgtt module option once
drm/i915: Break encoder->crtc link separately in intel_sanitize_crtc()
George Spelvin [Wed, 7 May 2014 21:05:52 +0000 (17:05 -0400)]
x86-64, build: Fix stack protector Makefile breakage with 32-bit userland
If you are using a 64-bit kernel with 32-bit userland, then
scripts/gcc-x86_64-has-stack-protector.sh invokes 32-bit gcc
with -mcmodel=kernel, which produces:
<stdin>:1:0: error: code model 'kernel' not supported in the 32 bit mode
and trips the "broken compiler" test at arch/x86/Makefile:120.
There are several places a fix is possible, but the following seems
cleanest. (But it's minimal; it would also be possible to factor
out a bunch of stuff from the two branches of the if.)
Dave Airlie [Tue, 6 May 2014 23:06:21 +0000 (09:06 +1000)]
Merge branch 'drm-nouveau-next' of git://anongit.freedesktop.org/git/nouveau/linux-2.6 into drm-fixes
nouveau fixes.
* 'drm-nouveau-next' of git://anongit.freedesktop.org/git/nouveau/linux-2.6:
drm/gm107/gr: bump attrib cb size quite a bit
drm/nouveau: fix another lock unbalance in nouveau_crtc_page_flip
drm/nouveau/bios: fix shadowing from PROM on big-endian systems
drm/nouveau/acpi: allow non-optimus setups to load vbios from acpi
Dave Airlie [Tue, 6 May 2014 22:56:03 +0000 (08:56 +1000)]
Merge tag 'topc/core-stuff-2014-05-05' of git://anongit.freedesktop.org/drm-intel into drm-fixes
Some more i915 fixes. There's still some DP issues we are looking into,
but wanted to get these moving.
* tag 'topc/core-stuff-2014-05-05' of git://anongit.freedesktop.org/drm-intel:
drm/i915: don't try DP_LINK_BW_5_4 on HSW ULX
drm/i915: Sanitize the enable_ppgtt module option once
drm/i915: Break encoder->crtc link separately in intel_sanitize_crtc()
Dave Airlie [Tue, 6 May 2014 22:55:27 +0000 (08:55 +1000)]
Merge branch 'drm-fixes-3.15' of git://people.freedesktop.org/~deathsimple/linux into drm-fixes
this is the next pull quested for stashed up radeon fixes for 3.15. As discussed support for Mullins was separated out and will get it's own pull request. Remaining highlights are:
1. Some more patches to better handle PLL limits.
2. Making use of the PFLIP additional to the VBLANK interrupt, otherwise we sometimes miss page flip events.
3. Fix for the UVD command stream parser.
4. Fix for bootup UVD clocks on RV7xx systems.
5. Adding missing error check on dpcd reads.
6. Fixes number of banks calculation on SI.
* 'drm-fixes-3.15' of git://people.freedesktop.org/~deathsimple/linux:
drm/radeon: lower the ref * post PLL maximum
drm/radeon: check that we have a clock before PLL setup
drm/radeon: drm/radeon: add missing radeon_semaphore_free to error path
drm/radeon: Fix num_banks calculation for SI
drm/radeon/dp: check for errors in dpcd reads
drm/radeon: avoid high jitter with small frac divs
drm/radeon: check buffer relocation offset
drm/radeon: use pflip irq on R600+ v2
drm/radeon/uvd: use lower clocks on old UVD to boot v2
Linus Torvalds [Tue, 6 May 2014 20:07:41 +0000 (13:07 -0700)]
Merge branch 'akpm' (incoming from Andrew)
Merge misc fixes from Andrew Morton:
"13 fixes"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
agp: info leak in agpioc_info_wrap()
fs/affs/super.c: bugfix / double free
fanotify: fix -EOVERFLOW with large files on 64-bit
slub: use sysfs'es release mechanism for kmem_cache
revert "mm: vmscan: do not swap anon pages just because free+file is low"
autofs: fix lockref lookup
mm: filemap: update find_get_pages_tag() to deal with shadow entries
mm/compaction: make isolate_freepages start at pageblock boundary
MAINTAINERS: zswap/zbud: change maintainer email address
mm/page-writeback.c: fix divide by zero in pos_ratio_polynom
hugetlb: ensure hugepage access is denied if hugepages are not supported
slub: fix memcg_propagate_slab_attrs
drivers/rtc/rtc-pcf8523.c: fix month definition
Dan Carpenter [Tue, 6 May 2014 19:50:12 +0000 (12:50 -0700)]
agp: info leak in agpioc_info_wrap()
On 64 bit systems the agp_info struct has a 4 byte hole between
->agp_mode and ->aper_base. We need to clear it to avoid disclosing
stack information to userspace.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Cc: David Airlie <airlied@linux.ie> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 842a859db26b ("affs: use ->kill_sb() to simplify ->put_super()
and failure exits of ->mount()") adds .kill_sb which frees sbi but
doesn't remove sbi free in case of parse_options error causing double
free+random crash.
Signed-off-by: Fabian Frederick <fabf@skynet.be> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: <stable@vger.kernel.org> [3.14.x] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Will Woods [Tue, 6 May 2014 19:50:10 +0000 (12:50 -0700)]
fanotify: fix -EOVERFLOW with large files on 64-bit
On 64-bit systems, O_LARGEFILE is automatically added to flags inside
the open() syscall (also openat(), blkdev_open(), etc). Userspace
therefore defines O_LARGEFILE to be 0 - you can use it, but it's a
no-op. Everything should be O_LARGEFILE by default.
But: when fanotify does create_fd() it uses dentry_open(), which skips
all that. And userspace can't set O_LARGEFILE in fanotify_init()
because it's defined to 0. So if fanotify gets an event regarding a
large file, the read() will just fail with -EOVERFLOW.
This patch adds O_LARGEFILE to fanotify_init()'s event_f_flags on 64-bit
systems, using the same test as open()/openat()/etc.
Signed-off-by: Will Woods <wwoods@redhat.com> Acked-by: Eric Paris <eparis@redhat.com> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Sysfs has a release mechanism. Use that to release the kmem_cache
structure if CONFIG_SYSFS is enabled.
Only slub is changed - slab currently only supports /proc/slabinfo and
not /sys/kernel/slab/*. We talked about adding that and someone was
working on it.
[akpm@linux-foundation.org: fix CONFIG_SYSFS=n build]
[akpm@linux-foundation.org: fix CONFIG_SYSFS=n build even more] Signed-off-by: Christoph Lameter <cl@linux.com> Reported-by: Sasha Levin <sasha.levin@oracle.com> Tested-by: Sasha Levin <sasha.levin@oracle.com> Acked-by: Greg KH <greg@kroah.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Pekka Enberg <penberg@kernel.org> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Bart Van Assche <bvanassche@acm.org> Cc: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Johannes Weiner [Tue, 6 May 2014 19:50:07 +0000 (12:50 -0700)]
revert "mm: vmscan: do not swap anon pages just because free+file is low"
This reverts commit 0bf1457f0cfc ("mm: vmscan: do not swap anon pages
just because free+file is low") because it introduced a regression in
mostly-anonymous workloads, where reclaim would become ineffective and
trap every allocating task in direct reclaim.
The problem is that there is a runaway feedback loop in the scan balance
between file and anon, where the balance tips heavily towards a tiny
thrashing file LRU and anonymous pages are no longer being looked at.
The commit in question removed the safe guard that would detect such
situations and respond with forced anonymous reclaim.
This commit was part of a series to fix premature swapping in loads with
relatively little cache, and while it made a small difference, the cure
is obviously worse than the disease. Revert it.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Reported-by: Christian Borntraeger <borntraeger@de.ibm.com> Acked-by: Christian Borntraeger <borntraeger@de.ibm.com> Acked-by: Rafael Aquini <aquini@redhat.com> Cc: Rik van Riel <riel@redhat.com> Cc: <stable@kernel.org> [3.12+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ian Kent [Tue, 6 May 2014 19:50:06 +0000 (12:50 -0700)]
autofs: fix lockref lookup
autofs needs to be able to see private data dentry flags for its dentrys
that are being created but not yet hashed and for its dentrys that have
been rmdir()ed but not yet freed. It needs to do this so it can block
processes in these states until a status has been returned to indicate
the given operation is complete.
It does this by keeping two lists, active and expring, of dentrys in
this state and uses ->d_release() to keep them stable while it checks
the reference count to determine if they should be used.
But with the recent lockref changes dentrys being freed sometimes don't
transition to a reference count of 0 before being freed so autofs can
occassionally use a dentry that is invalid which can lead to a panic.
Signed-off-by: Ian Kent <raven@themaw.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1343 /*
1344 * This function is never used on a shmem/tmpfs
1345 * mapping, so a swap entry won't be found here.
1346 */
1347 BUG();
After commit 0cd6144aadd2 ("mm + fs: prepare for non-page entries in
page cache radix trees") this comment and BUG() are out of date because
exceptional entries can now appear in all mappings - as shadows of
recently evicted pages.
However, as Hugh Dickins notes,
"it is truly surprising for a PAGECACHE_TAG_WRITEBACK (and probably
any other PAGECACHE_TAG_*) to appear on an exceptional entry.
I expect it comes down to an occasional race in RCU lookup of the
radix_tree: lacking absolute synchronization, we might sometimes
catch an exceptional entry, with the tag which really belongs with
the unexceptional entry which was there an instant before."
And indeed, not only is the tree walk lockless, the tags are also read
in chunks, one radix tree node at a time. There is plenty of time for
page reclaim to swoop in and replace a page that was already looked up
as tagged with a shadow entry.
Remove the BUG() and update the comment. While reviewing all other
lookup sites for whether they properly deal with shadow entries of
evicted pages, update all the comments and fix memcg file charge moving
to not miss shmem/tmpfs swapcache pages.
Fixes: 0cd6144aadd2 ("mm + fs: prepare for non-page entries in page cache radix trees") Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Reported-by: Dave Jones <davej@redhat.com> Acked-by: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Vlastimil Babka [Tue, 6 May 2014 19:50:03 +0000 (12:50 -0700)]
mm/compaction: make isolate_freepages start at pageblock boundary
The compaction freepage scanner implementation in isolate_freepages()
starts by taking the current cc->free_pfn value as the first pfn. In a
for loop, it scans from this first pfn to the end of the pageblock, and
then subtracts pageblock_nr_pages from the first pfn to obtain the first
pfn for the next for loop iteration.
This means that when cc->free_pfn starts at offset X rather than being
aligned on pageblock boundary, the scanner will start at offset X in all
scanned pageblock, ignoring potentially many free pages. Currently this
can happen when
a) zone's end pfn is not pageblock aligned, or
b) through zone->compact_cached_free_pfn with CONFIG_HOLES_IN_ZONE
enabled and a hole spanning the beginning of a pageblock
This patch fixes the problem by aligning the initial pfn in
isolate_freepages() to pageblock boundary. This also permits replacing
the end-of-pageblock alignment within the for loop with a simple
pageblock_nr_pages increment.
Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Reported-by: Heesub Shin <heesub.shin@samsung.com> Acked-by: Minchan Kim <minchan@kernel.org> Cc: Mel Gorman <mgorman@suse.de> Acked-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Christoph Lameter <cl@linux.com> Acked-by: Rik van Riel <riel@redhat.com> Cc: Dongjun Shin <d.j.shin@samsung.com> Cc: Sunghwan Yun <sunghwan.yun@samsung.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rik van Riel [Tue, 6 May 2014 19:50:01 +0000 (12:50 -0700)]
mm/page-writeback.c: fix divide by zero in pos_ratio_polynom
It is possible for "limit - setpoint + 1" to equal zero, after getting
truncated to a 32 bit variable, and resulting in a divide by zero error.
Using the fully 64 bit divide functions avoids this problem. It also
will cause pos_ratio_polynom() to return the correct value when
(setpoint - limit) exceeds 2^32.
Also uninline pos_ratio_polynom, at Andrew's request.
hugetlb: ensure hugepage access is denied if hugepages are not supported
Currently, I am seeing the following when I `mount -t hugetlbfs /none
/dev/hugetlbfs`, and then simply do a `ls /dev/hugetlbfs`. I think it's
related to the fact that hugetlbfs is properly not correctly setting
itself up in this state?:
Unable to handle kernel paging request for data at address 0x00000031
Faulting instruction address: 0xc000000000245710
Oops: Kernel access of bad area, sig: 11 [#1]
SMP NR_CPUS=2048 NUMA pSeries
....
In KVM guests on Power, in a guest not backed by hugepages, we see the
following:
HPAGE_SHIFT == 0 in this configuration, which indicates that hugepages
are not supported at boot-time, but this is only checked in
hugetlb_init(). Extract the check to a helper function, and use it in a
few relevant places.
This does make hugetlbfs not supported (not registered at all) in this
environment. I believe this is fine, as there are no valid hugepages
and that won't change at runtime.
[akpm@linux-foundation.org: use pr_info(), per Mel]
[akpm@linux-foundation.org: fix build when HPAGE_SHIFT is undefined] Signed-off-by: Nishanth Aravamudan <nacc@linux.vnet.ibm.com> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Acked-by: Mel Gorman <mgorman@suse.de> Cc: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
After creating a cache for a memcg we should initialize its sysfs attrs
with the values from its parent. That's what memcg_propagate_slab_attrs
is for. Currently it's broken - we clearly muddled root-vs-memcg caches
there. Let's fix it up.
Signed-off-by: Vladimir Davydov <vdavydov@parallels.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linus Torvalds [Tue, 6 May 2014 19:22:20 +0000 (12:22 -0700)]
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs fixes from Al Viro:
"dcache fixes + kvfree() (uninlined, exported by mm/util.c) + posix_acl
bugfix from hch"
The dcache fixes are for a subtle LRU list corruption bug reported by
Miklos Szeredi, where people inside IBM saw list corruptions with the
LTP/host01 test.
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
nick kvfree() from apparmor
posix_acl: handle NULL ACL in posix_acl_equiv_mode
dcache: don't need rcu in shrink_dentry_list()
more graceful recovery in umount_collect()
don't remove from shrink list in select_collect()
dentry_kill(): don't try to remove from shrink list
expand the call of dentry_lru_del() in dentry_kill()
new helper: dentry_free()
fold try_prune_one_dentry()
fold d_kill() and d_free()
fix races between __d_instantiate() and checks of dentry flags
posix_acl: handle NULL ACL in posix_acl_equiv_mode
Various filesystems don't bother checking for a NULL ACL in
posix_acl_equiv_mode, and thus can dereference a NULL pointer when it
gets passed one. This usually happens from the NFS server, as the ACL tools
never pass a NULL ACL, but instead of one representing the mode bits.
Instead of adding boilerplat to all filesystems put this check into one place,
which will allow us to remove the check from other filesystems as well later
on.
Signed-off-by: Christoph Hellwig <hch@lst.de> Reported-by: Ben Greear <greearb@candelatech.com> Reported-by: Marco Munderloh <munderl@tnt.uni-hannover.de>, Cc: Chuck Lever <chuck.lever@oracle.com> Cc: stable@vger.kernel.org Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Linus Torvalds [Tue, 6 May 2014 16:09:35 +0000 (09:09 -0700)]
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse
Pull fuse fixes from Miklos Szeredi:
"This adds ctime update in the new cached writeback mode and also
fixes/simplifies the mtime update handling. Support for rename flags
(aka renameat2) is also added to the userspace API"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
fuse: add renameat2 support
fuse: clear MS_I_VERSION
fuse: clear FUSE_I_CTIME_DIRTY flag on setattr
fuse: trust kernel i_ctime only
fuse: remove .update_time
fuse: allow ctime flushing to userspace
fuse: fuse: add time_gran to INIT_OUT
fuse: add .write_inode
fuse: clean up fsync
fuse: fuse: fallocate: use file_update_time()
fuse: update mtime on open(O_TRUNC) in atomic_o_trunc mode
fuse: update mtime on truncate(2)
fuse: do not use uninitialized i_mode
fuse: fix mtime update error in fsync
fuse: check fallocate mode
fuse: add __exit to fuse_ctl_cleanup
Pull sparc fixes from David Miller:
"I've been auditing the THP support on sparc64 and found several bugs,
hopefully most of which are fixed completely here.
Also an RT kernel locking fix from Kirill Tkhai"
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
sparc64: Give more detailed information in {pgd,pmd}_ERROR() and kill pte_ERROR().
sparc64: Add basic validations to {pud,pmd}_bad().
sparc64: Use 'ILOG2_4MB' instead of constant '22'.
sparc64: Fix range check in kern_addr_valid().
sparc64: Fix top-level fault handling bugs.
sparc64: Handle 32-bit tasks properly in compute_effective_address().
sparc64: Don't use _PAGE_PRESENT in pte_modify() mask.
sparc64: Fix hex values in comment above pte_modify().
sparc64: Fix bugs in get_user_pages_fast() wrt. THP.
sparc64: Fix huge PMD invalidation.
sparc64: Fix executable bit testing in set_pmd_at() paths.
sparc64: Normalize NMI watchdog logging and behavior.
sparc64: Make itc_sync_lock raw
sparc64: Fix argument sign extension for compat_sys_futex().