Quite a few functions that get called from the tlb gather code require that
preemption must be disabled. So disable preemption inside of the called
functions instead.
The only drawback is that rcu_table_freelist_finish() doesn't get necessarily
called on the cpu(s) that filled the free lists. So we may see a delay, until
we finally see an rcu callback. However over time this shouldn't matter.
So we get rid of lots of "BUG: using smp_processor_id() in preemptible"
messages.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
page_get_storage_key() and page_set_storage_key() expect a page address
and not its page frame number. This got inconsistent with 2d42552d
"[S390] merge page_test_dirty and page_clear_dirty".
Result is that we read/write storage keys from random pages and do not
have a working dirty bit tracking at all.
E.g. SetPageUpdate() doesn't clear the dirty bit of requested pages, which
for example ext4 doesn't like very much and panics after a while.
Unable to handle kernel paging request at virtual user address (null)
Oops: 0004 [#1] PREEMPT SMP DEBUG_PAGEALLOC
Modules linked in:
CPU: 1 Not tainted 2.6.39-07551-g139f37f-dirty #152
Process flush-94:0 (pid: 1576, task: 000000003eb34538, ksp: 000000003c287b70)
Krnl PSW : 0704c00180000000 0000000000316b12 (jbd2_journal_file_inode+0x10e/0x138)
R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:0 PM:0 EA:3
Krnl GPRS: 0000000000000000 0000000000000000 0000000000000000 0700000000000000
0000000000316a62 000000003eb34cd0 0000000000000025 000000003c287b88
0000000000000001 000000003c287a70 000000003f1ec678 000000003f1ec000
0000000000000000 000000003e66ec00 0000000000316a62 000000003c287988
Krnl Code: 0000000000316b04: f0a0000407f4 srp 4(11,%r0),2036,0
0000000000316b0a: b9020022 ltgr %r2,%r2
0000000000316b0e: a7740015 brc 7,316b38
>0000000000316b12: e3d0c0000024 stg %r13,0(%r12)
0000000000316b18: 4120c010 la %r2,16(%r12)
0000000000316b1c: 4130d060 la %r3,96(%r13)
0000000000316b20: e340d0600004 lg %r4,96(%r13)
0000000000316b26: c0e50002b567 brasl %r14,36d5f4
Call Trace:
([<0000000000316a62>] jbd2_journal_file_inode+0x5e/0x138)
[<00000000002da13c>] mpage_da_map_and_submit+0x2e8/0x42c
[<00000000002daac2>] ext4_da_writepages+0x2da/0x504
[<00000000002597e8>] writeback_single_inode+0xf8/0x268
[<0000000000259f06>] writeback_sb_inodes+0xd2/0x18c
[<000000000025a700>] writeback_inodes_wb+0x80/0x168
[<000000000025aa92>] wb_writeback+0x2aa/0x324
[<000000000025abde>] wb_do_writeback+0xd2/0x274
[<000000000025ae3a>] bdi_writeback_thread+0xba/0x1c4
[<00000000001737be>] kthread+0xa6/0xb0
[<000000000056c1da>] kernel_thread_starter+0x6/0xc
[<000000000056c1d4>] kernel_thread_starter+0x0/0xc
INFO: lockdep is turned off.
Last Breaking-Event-Address:
[<0000000000316a8a>] jbd2_journal_file_inode+0x86/0x138
Reported-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
mwait_idle() is a C1-only idle loop intended to be more efficient
than HLT on SMP hardware that supports it.
But mwait_idle() has been replaced by the more general
mwait_idle_with_hints(), which handles both C1 and deeper C-states.
ACPI uses only mwait_idle_with_hints(), and never uses mwait_idle().
Deprecate mwait_idle() and the "idle=mwait" cmdline param
to simplify the x86 idle code.
After this change, kernels configured with
(!CONFIG_ACPI=n && !CONFIG_INTEL_IDLE=n) when run on hardware
that support MWAIT will simply use HLT. If MWAIT is desired
on those systems, cpuidle and the cpuidle drivers above
can be used.
cc: x86@kernel.org
cc: stable@kernel.org # .39.x
Signed-off-by: Len Brown <len.brown@intel.com>
We'd rather that modern machines not check if HLT works on
every entry into idle, for the benefit of machines that had
marginal electricals 15-years ago. If those machines are still running
the upstream kernel, they can use "idle=poll". The only difference
will be that they'll now invoke HLT in machine_hlt().
cc: x86@kernel.org # .39.x
Signed-off-by: Len Brown <len.brown@intel.com>
We don't want to export the pm_idle function pointer to modules.
Currently CONFIG_APM_CPU_IDLE w/ CONFIG_APM_MODULE forces us to.
CONFIG_APM_CPU_IDLE is of dubious value, it runs only on 32-bit
uniprocessor laptops that are over 10 years old. It calls into
the BIOS during idle, and is known to cause a number of machines
to fail.
Removing CONFIG_APM_CPU_IDLE and will allow us to stop exporting
pm_idle. Any systems that were calling into the APM BIOS
at run-time will simply use HLT instead.
cc: x86@kernel.org
cc: Jiri Kosina <jkosina@suse.cz>
cc: stable@kernel.org # .39.x
Signed-off-by: Len Brown <len.brown@intel.com>
In the long run, we don't want default_idle() or (pm_idle)() to
be exported outside of process.c. Start by not exporting them
to modules, unless the APM build demands it.
cc: x86@kernel.org
cc: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Len Brown <len.brown@intel.com>
The workaround for AMD erratum 400 uses the term "c1e" falsely suggesting:
1. Intel C1E is somehow involved
2. All AMD processors with C1E are involved
Use the string "amd_c1e" instead of simply "c1e" to clarify that
this workaround is specific to AMD's version of C1E.
Use the string "e400" to clarify that the workaround is specific
to AMD processors with Erratum 400.
This patch is text-substitution only, with no functional change.
cc: x86@kernel.org
Acked-by: Borislav Petkov <borislav.petkov@amd.com>
Signed-off-by: Len Brown <len.brown@intel.com>
The documentation is a little iffy as to whether these are actual MMRs,
but reading them on the hardware works, and the previous version of this
logic (the SDH) had PID[4567]. So add it for RSI too.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Looks like the copying of MMR defines from the SDH block missed updating
the addresses of the RSI_PID# registers. So tweak them to reflect the
actual hardware.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
The bf52x/bf54x have the incorrect addresses for USB_EP_NI7_RXINTERVAL
and USB_EP_NI7_TXCOUNT, so adjust those.
Further, the bf54x header puts the USB defines in the wrong place, so
shuffle them back to the right grouping.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
This code was mostly developed against a BF54x, so some BF537-specific
issues were missed.
The PPI block starts at PPI_CONTROL, not PPI_STATUS (which is the reverse
of the EPPI block).
The MDMA block starts at MDMA_NEXT_DESC_PTR, not MDMA_CONFIG. Seems the
sim does not catch misreads here so that'll need to get fixed.
The gptimer block is mostly 32bit regs, not 16bit. Use the gptimer struct
to figure that out rather than hardcoding it locally.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Now that the serial code has been unified in bfin_serial.h, and the
Blackfin UART driver pushed its resources to the boards files, we
don't need these headers anymore.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Any consumer that needs to access the MMRs has to provide these helpers,
so make the default into useless stubs.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
32bit and 64bit on x86 are tested and working. The rest I have looked
at closely and I can't find any problems.
setns is an easy system call to wire up. It just takes two ints so I
don't expect any weird architecture porting problems.
While doing this I have noticed that we have some architectures that are
very slow to get new system calls. cris seems to be the slowest where
the last system calls wired up were preadv and pwritev. avr32 is weird
in that recvmmsg was wired up but never declared in unistd.h. frv is
behind with perf_event_open being the last syscall wired up. On h8300
the last system call wired up was epoll_wait. On m32r the last system
call wired up was fallocate. mn10300 has recvmmsg as the last system
call wired up. The rest seem to at least have syncfs wired up which was
new in the 2.6.39.
v2: Most of the architecture support added by Daniel Lezcano <dlezcano@fr.ibm.com>
v3: ported to v2.6.36-rc4 by: Eric W. Biederman <ebiederm@xmission.com>
v4: Moved wiring up of the system call to another patch
v5: ported to v2.6.39-rc6
v6: rebased onto parisc-next and net-next to avoid syscall conflicts.
v7: ported to Linus's latest post 2.6.39 tree.
> arch/blackfin/include/asm/unistd.h | 3 ++-
> arch/blackfin/mach-common/entry.S | 1 +
Acked-by: Mike Frysinger <vapier@gentoo.org>
Oh - ia64 wiring looks good.
Acked-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The software division functions never had unwinding annotations
added. Currently, when a division by zero occurs the backtrace shown
will stop at Ldiv0 or some completely unrelated function. Add
unwinding annotations in hopes of getting a more useful backtrace
when a division by zero occurs.
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
Acked-by: Dave Martin <dave.martin@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Register offset defines are moved to <plat/gpio.h> so they can be used
by SoC-specific device init code to fill out platform_data register
offsets.
Signed-off-by: Kevin Hilman <khilman@ti.com>
This change introduces a few of the less controversial /proc and
/proc/sys interfaces for tile, along with sysfs attributes for
various things that were originally proposed as /proc/tile files.
It also adjusts the "hardwall" proc API.
Arnd Bergmann reviewed the initial arch/tile submission, which
included a complete set of all the /proc/tile and /proc/sys/tile
knobs that we had added in a somewhat ad hoc way during initial
development, and provided feedback on where most of them should go.
One knob turned out to be similar enough to the existing
/proc/sys/debug/exception-trace that it was re-implemented to use
that model instead.
Another knob was /proc/tile/grid, which reported the "grid" dimensions
of a tile chip (e.g. 8x8 processors = 64-core chip). Arnd suggested
looking at sysfs for that, so this change moves that information
to a pair of sysfs attributes (chip_width and chip_height) in the
/sys/devices/system/cpu directory. We also put the "chip_serial"
and "chip_revision" information from our old /proc/tile/board file
as attributes in /sys/devices/system/cpu.
Other information collected via hypervisor APIs is now placed in
/sys/hypervisor. We create a /sys/hypervisor/type file (holding the
constant string "tilera") to be parallel with the Xen use of
/sys/hypervisor/type holding "xen". We create three top-level files,
"version" (the hypervisor's own version), "config_version" (the
version of the configuration file), and "hvconfig" (the contents of
the configuration file). The remaining information from our old
/proc/tile/board and /proc/tile/switch files becomes an attribute
group appearing under /sys/hypervisor/board/.
Finally, after some feedback from Arnd Bergmann for the previous
version of this patch, the /proc/tile/hardwall file is split up into
two conceptual parts. First, a directory /proc/tile/hardwall/ which
contains one file per active hardwall, each file named after the
hardwall's ID and holding a cpulist that says which cpus are enclosed by
the hardwall. Second, a /proc/PID file "hardwall" that is either
empty (for non-hardwall-using processes) or contains the hardwall ID.
Finally, this change pushes the /proc/sys/tile/unaligned_fixup/
directory, with knobs controlling the kernel code for handling the
fixup of unaligned exceptions.
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
The implementation of find_next_bit_le() on m68knommu is identical with
the generic implementation of find_next_bit_le().
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Greg Ungerer <gerg@uclinux.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The previous style change enables to use asm-generic/bitops/le.h on s390.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Greg Ungerer <gerg@uclinux.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The previous style change enables to use asm-generic/bitops/le.h on arm.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Greg Ungerer <gerg@uclinux.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
By the previous style change, CONFIG_GENERIC_FIND_NEXT_BIT,
CONFIG_GENERIC_FIND_BIT_LE, and CONFIG_GENERIC_FIND_LAST_BIT are not used
to test for existence of find bitops anymore.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Acked-by: Greg Ungerer <gerg@uclinux.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The style that we normally use in asm-generic is to test the macro itself
for existence, so in asm-generic, do:
#ifndef find_next_zero_bit_le
extern unsigned long find_next_zero_bit_le(const void *addr,
unsigned long size, unsigned long offset);
#endif
and in the architectures, write
static inline unsigned long find_next_zero_bit_le(const void *addr,
unsigned long size, unsigned long offset)
#define find_next_zero_bit_le find_next_zero_bit_le
This adds the #define for each of the optimized find bitops in the
architectures.
Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Acked-by: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Greg Ungerer <gerg@uclinux.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
m68knommu can't build ext4, udf, and ocfs2 due to the lack of
find_next_bit_le().
This implements find_next_bit_le() on m68knommu by duplicating the generic
find_next_bit_le() in lib/find_next_bit.c.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Acked-by: Greg Ungerer <gerg@uclinux.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The Blackfin arch, like the x86 arch, needs to adjust the PC manually
after a breakpoint is hit as normally this is handled by the remote gdb.
However, rather than starting another arch ifdef mess, create a common
GDB_ADJUSTS_BREAK_OFFSET define for any arch to opt-in via their kgdb.h.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Acked-by: Dongdong Deng <dongdong.deng@windriver.com>
Cc: Sergei Shtylyov <sshtylyov@mvista.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The ns_cgroup is an annoying cgroup at the namespace / cgroup frontier and
leads to some problems:
* cgroup creation is out-of-control
* cgroup name can conflict when pids are looping
* it is not possible to have a single process handling a lot of
namespaces without falling in a exponential creation time
* we may want to create a namespace without creating a cgroup
The ns_cgroup was replaced by a compatibility flag 'clone_children',
where a newly created cgroup will copy the parent cgroup values.
The userspace has to manually create a cgroup and add a task to
the 'tasks' file.
This patch removes the ns_cgroup as suggested in the following thread:
https://lists.linux-foundation.org/pipermail/containers/2009-June/018616.html
The 'cgroup_clone' function is removed because it is no longer used.
This is a userspace-visible change. Commit 45531757b4 ("cgroup: notify
ns_cgroup deprecated") (merged into 2.6.27) caused the kernel to emit a
printk warning users that the feature is planned for removal. Since that
time we have heard from XXX users who were affected by this.
Signed-off-by: Daniel Lezcano <daniel.lezcano@free.fr>
Signed-off-by: Serge E. Hallyn <serge.hallyn@canonical.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Jamal Hadi Salim <hadi@cyberus.ca>
Reviewed-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Paul Menage <menage@google.com>
Acked-by: Matt Helsley <matthltc@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
They have no meaning.
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We plan to remove cpus_xx() old cpumask APIs later. Also, we plan to
change mm_cpu_mask() implementation, allocate only nr_cpu_ids, thus
*mm_cpu_mask() is dangerous operation.
Then, this patch convert them.
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Move the Samsung s5pc100 SoC GPIO driver to drivers/gpio
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Move the Samsung s5pv210 SoC GPIO driver to drivers/gpio
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Move the Samsung Exynos4 series SoCs GPIO driver to drivers/gpio
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
It's common gpiolib for recent Samsung SoCs. Move to drivers/gpio
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
This moves the Nomadik GPIO driver out of arch/arm/plat-nomadik
and into the desired location indicated by the subsystem
maintainer.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
[grant.likely: squashed with kconfig fixup]
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
This moves the U300 GPIO driver out of arch/arm/mach-u300 and into
the desired location indicated by the subsystem maintainer.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Modifying the macro name Main_Ref to all caps(MAIN_REF).
Suggested by Nishanth Menon <nm@ti.com>
Signed-off-by: Lesly A M <leslyam@ti.com>
Cc: Nishanth Menon <nm@ti.com>
Cc: David Derrick <dderrick@ti.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Commit b87cf80af3 added support for
ARAT (Always Running APIC timer) on AMD processors that are not
affected by erratum 400. This erratum is present on certain processor
families and prevents APIC timer from waking up the CPU when it
is in a deep C state, including C1E state.
Determining whether a processor is affected by this erratum may
have some corner cases and handling these cases is somewhat
complicated. In the interest of simplicity we won't claim ARAT
support on processor families below 0x12 and will go back to
broadcasting timer when going idle.
Signed-off-by: Boris Ostrovsky <ostr@amd64.org>
Link: http://lkml.kernel.org/r/1306423192-19774-1-git-send-email-ostr@amd64.org
Tested-by: Boris Petkov <borislav.petkov@amd.com>
Cc: Hans Rosenfeld <Hans.Rosenfeld@amd.com>
Cc: Andreas Herrmann <Andreas.Herrmann3@amd.com>
Cc: Chuck Ebbert <cebbert@redhat.com>
Cc: stable@kernel.org # 32.x, 38.x, 39.x
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
This patch provides a shim between the kernel-internal cleancache
API (see Documentation/mm/cleancache.txt) and the Xen Transcendent
Memory ABI (see http://oss.oracle.com/projects/tmem).
Xen tmem provides "hypervisor RAM" as an ephemeral page-oriented
pseudo-RAM store for cleancache pages, shared cleancache pages,
and frontswap pages. Tmem provides enterprise-quality concurrency,
full save/restore and live migration support, compression
and deduplication.
A presentation showing up to 8% faster performance and up to 52%
reduction in sectors read on a kernel compile workload, despite
aggressive in-kernel page reclamation ("self-ballooning") can be
found at:
http://oss.oracle.com/projects/tmem/dist/documentation/presentations/TranscendentMemoryXenSummit2010.pdf
Signed-off-by: Dan Magenheimer <dan.magenheimer@oracle.com>
Reviewed-by: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Matthew Wilcox <matthew@wil.cx>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Rik Van Riel <riel@redhat.com>
Cc: Jan Beulich <JBeulich@novell.com>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Andreas Dilger <adilger@sun.com>
Cc: Ted Ts'o <tytso@mit.edu>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <joel.becker@oracle.com>
Cc: Nitin Gupta <ngupta@vflare.org>
Ingo suggested SIGKILL check should be moved into slowpath
function. This will reduce the page fault fastpath impact
of this recent commit:
37b23e0525d3: x86,mm: make pagefault killable
Suggested-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: kamezawa.hiroyu@jp.fujitsu.com
Cc: minchan.kim@gmail.com
Cc: willy@linux.intel.com
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/4DDE0B5C.9050907@jp.fujitsu.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Now that ASID 0 is no longer used as a reserved value, allow it to be
allocated to tasks.
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
On ARMv7 CPUs that cache first level page table entries (like the
Cortex-A15), using a reserved ASID while changing the TTBR or flushing
the TLB is unsafe.
This is because the CPU may cache the first level entry as the result of
a speculative memory access while the reserved ASID is assigned. After
the process owning the page tables dies, the memory will be reallocated
and may be written with junk values which can be interpreted as global,
valid PTEs by the processor. This will result in the TLB being populated
with bogus global entries.
This patch avoids the use of a reserved context ID in the v7 switch_mm
and ASID rollover code by temporarily using the swapper_pg_dir pointed
at by TTBR1, which contains only global entries that are not tagged
with ASIDs.
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This patch makes TTBR1 point to swapper_pg_dir so that global, kernel
mappings can be used exclusively on v6 and v7 cores where they are
needed.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Heiko Carstens