| Age | Commit message (Collapse) | Author |
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Existing code in there (get_tty(), etc.) is both severely
racy *and* pointless: ioctls in question have Linux equivalents
and there's no need to play silly buggers in irix_ioctl() -
just need to replace arguments and, in case of TIOCGSID,
deal with API differences - Linux one expects pid_t __user *
while Irix one does unsigned long __user *. BFD...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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Races galore... General rule: as soon as it's in descriptor table,
it's over; another thread might have started IO on it/dup2() it
elsewhere/dup2() something *over* it/etc. fd_install() is the very
last step one should take - it's a point of no return.
Besides, the damn thing leaked on failure exits...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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So Ingo finally did figure out why UML broke with this option: UML
passes gcc the -fno-unit-at-a-time flag, and apparently that wreaks
havoc with gcc's inlining.
We could turn off -fno-unit-at-a-time for UML for gcc4+ (which is what
x86 does), but there's bad blood about this whole option, and it does
show that the thing is just fragile as heck.
So let tempers cool, and disable the thing, and we can revisit the
decision later.
Cc: Adrian Bunk <bunk@kernel.org>
Cc: David Miller <davem@davemloft.net>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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do not override the existing pci-y rule when adding visws or
numaq rules.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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Switch back to 8K stacks as the safer default. Out-of-memory
situations are less problematic than silent and hard to debug
stack corruption.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
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bdd3cee2e4b7279457139058615ced6c2b41e7de (x86: ioremap(), extend check
to all RAM pages) breaks OLPC's ioremap call. The ioremap that OLPC uses is:
romsig = ioremap(0xffffffc0, 16);
The commit that breaks it is basically:
- for (pfn = phys_addr >> PAGE_SHIFT; pfn < max_pfn_mapped &&
- (pfn << PAGE_SHIFT) < last_addr; pfn++) {
+ for (pfn = phys_addr >> PAGE_SHIFT;
+ (pfn << PAGE_SHIFT) < last_addr; pfn++) {
+
Previously, the 'pfn < max_pfn_mapped' check would've caused us to not
enter the loop. Removing that check means we loop infinitely. The
reason for that is because pfn is 0xfffff, and last_addr is 0xffffffcf.
The remaining check that is used to exit the loop is not sufficient;
when pfn<<PAGE_SHIFT is 0xfffff000, that is less than 0xffffffcf; when
we increment pfn and it overflows (pfn == 0x100000), pfn<<PAGE_SHIFT
ends up being 0. That, of course, is less than last_addr. In effect,
pfn<<PAGE_SHIFT is never lower than last_addr.
The simple fix for this is to limit the last_addr check to the PAGE_MASK;
a patch is below.
Signed-off-by: Andres Salomon <dilinger@debian.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
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default to inline optimizing off.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
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move the X86_CPU section out of the !X86_ELAN branch.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
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Andrew noticed that OPTIMIZE_INLINING appeared in the toplevel
menu - fix it.
Reported-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
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ioremap_nocache() and pci_mmap_page_range()
Use UC_MINUS for ioremap(), ioremap_nocache() instead of strong UC.
Once all the X drivers move to ioremap_wc(), we can go back to strong
UC semantics for ioremap() and ioremap_nocache().
To avoid attribute aliasing issues, pci_mmap_page_range() will also
use UC_MINUS for default non write-combining mapping request.
Next steps:
a) change all the video drivers using ioremap() or ioremap_nocache()
and adding WC MTTR using mttr_add() to ioremap_wc()
b) for strict usage, we can go back to strong uc semantics
for ioremap() and ioremap_nocache() after some grace period for
completing step-a.
c) user level X server needs to use the appropriate method for setting
up WC mapping (like using resourceX_wc sysfs file instead of
adding MTRR for WC and using /dev/mem or resourceX under /sys)
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
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Daniel Drake <dsd@gentoo.org> reported:
In 2.6.23, if you unpacked a kernel source tarball and then
ran "make menuconfig" you'd be presented with this message:
# using defaults found in arch/i386/defconfig
and the default options would be set.
The same thing in 2.6.24 does not give you any "using defaults" message, and
the default config options within menuconfig are rather blank (e.g. no PCI
support). You can work around this by explicitly running "make defconfig"
before menuconfig, but it would be nice to have the behaviour the way it was
for 2.6.23 (and the way it still is for other archs).
Fixed by adding a x86 specific defconfig list to Kconfig.
Fixes: http://bugzilla.kernel.org/show_bug.cgi?id=10470
Tested-by: dsd@gentoo.org
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
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Vegard Nossum reported a large (150 seconds) boot delay during bootup,
and bisected it to "x86: ioremap(), extend check to all RAM pages"
(commit bdd3cee2e4b). Revert this commit for now.
Bisected-by: Vegard Nossum <vegard.nossum@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
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The kernel prints the compat vdso address regardless of whether compat
vdso mode is enabled or not, which is confusing. Given that this
isn't very interesting information anyway, just remove the printk.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Gerhard Mack <gmack@innerfire.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
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Don't warn in read_apic_id() when preemptible but only one CPU online.
Signed-off-by: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
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The .asciz directive takes any number of strings, but each one is zero-
terminated, and string pasting is not done as in C. That results in only the
first line being output.
Replace .asciz with multiple .ascii directives and terminate with .asciz.
Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
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The iommu_sac_force variable is needlessly defined global,
and this patch makes it static. Additionally, this variable
needs not be explicitly initialized.
Signed-off-by: Dmitri Vorobiev <dmitri.vorobiev@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
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This patch fixes one sparse warning by including the appropriate
header for the reboot_force symbol.
Signed-off-by: Dmitri Vorobiev <dmitri.vorobiev@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
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the 'reboot_force' flag is a notion that non-PC subarchitectures do
not have.
also, unify the X86_BIOS_REBOOT option between 32-bit and 64-bit
and get rid of a few unnecessary Kconfig and Makefile complications
that way.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
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James Bottomley reported that the following commit:
| commit 6371b495991debfd1417b17c2bc4f7d7bae05739
| Author: Ingo Molnar <mingo@elte.hu>
| Date: Wed Jan 30 13:33:40 2008 +0100
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| x86: change ioremap() to default to uncached
broke Voyager.
James says:
" it broke a class of voyager machines: those which
rely on the quad interrupt controller (QIC). The precis of why they
broke is because the QIC does IPIs (or CPIs in its terminology) via
cache line interference: you interrupt a processor by moving a
designated memory area to write exclusive in the cache (by simply
writing to the line) and the CPU acks the interrupt by moving it back to
read shared (by reading from it). That area, is, of course, mapped by
ioremap, so reversing the ioremap semantics and adding the uncached bit
completely breaks the QIC. "
Sorry about that!
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
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Al Viro pointed out that there's a missing readl() of timer->hpet_config,
found by Sparse.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
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This patch removes the no longer used export of kmap_atomic_to_page.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
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git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6
* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6: (179 commits)
ACPI: Fix acpi_processor_idle and idle= boot parameters interaction
acpi: fix section mismatch warning in pnpacpi
intel_menlo: fix build warning
ACPI: Cleanup: Remove unneeded, multiple local dummy variables
ACPI: video - fix permissions on some proc entries
ACPI: video - properly handle errors when registering proc elements
ACPI: video - do not store invalid entries in attached_array list
ACPI: re-name acpi_pm_ops to acpi_suspend_ops
ACER_WMI/ASUS_LAPTOP: fix build bug
thinkpad_acpi: fix possible NULL pointer dereference if kstrdup failed
ACPI: check a return value correctly in acpi_power_get_context()
#if 0 acpi/bay.c:eject_removable_drive()
eeepc-laptop: add hwmon fan control
eeepc-laptop: add backlight
eeepc-laptop: add base driver
ACPI: thinkpad-acpi: bump up version to 0.20
ACPI: thinkpad-acpi: fix selects in Kconfig
ACPI: thinkpad-acpi: use a private workqueue
ACPI: thinkpad-acpi: fluff really minor fix
ACPI: thinkpad-acpi: use uppercase for "LED" on user documentation
...
Fixed conflicts in drivers/acpi/video.c and drivers/misc/intel_menlow.c
manually.
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'bugzilla-9916', 'ec', 'eeepc', 'idle', 'misc', 'pm-legacy', 'sysfs-links-2.6.26', 'thermal', 'thinkpad' and 'video' into release
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* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6:
sparc64: remove duplicated include
sparc: Add kgdb support.
kgdbts: Sparc needs sstep emulation.
sparc32: Kill smp_message_pass() and related code.
sparc64: Kill PIL_RESERVED, unused.
sparc64: Split entry.S up into seperate files.
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* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (53 commits)
tcp: Overflow bug in Vegas
[IPv4] UFO: prevent generation of chained skb destined to UFO device
iwlwifi: move the selects to the tristate drivers
ipv4: annotate a few functions __init in ipconfig.c
atm: ambassador: vcc_sf semaphore to mutex
MAINTAINERS: The socketcan-core list is subscribers-only.
netfilter: nf_conntrack: padding breaks conntrack hash on ARM
ipv4: Update MTU to all related cache entries in ip_rt_frag_needed()
sch_sfq: use del_timer_sync() in sfq_destroy()
net: Add compat support for getsockopt (MCAST_MSFILTER)
net: Several cleanups for the setsockopt compat support.
ipvs: fix oops in backup for fwmark conn templates
bridge: kernel panic when unloading bridge module
bridge: fix error handling in br_add_if()
netfilter: {nfnetlink,ip,ip6}_queue: fix skb_over_panic when enlarging packets
netfilter: x_tables: fix net namespace leak when reading /proc/net/xxx_tables_names
netfilter: xt_TCPOPTSTRIP: signed tcphoff for ipv6_skip_exthdr() retval
tcp: Limit cwnd growth when deferring for GSO
tcp: Allow send-limited cwnd to grow up to max_burst when gso disabled
[netdrvr] gianfar: Determine TBIPA value dynamically
...
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* 'for-linus' of git://git390.osdl.marist.edu/pub/scm/linux-2.6:
[S390] Update default configuration.
[S390] use generic sys_ptrace
[S390] Remove self ptrace IEEE_IP hack.
[S390] Convert to SPARSEMEM & SPARSEMEM_VMEMMAP
[S390] System z large page support.
[S390] Convert machine feature detection code to C.
[S390] vmemmap: use clear_table to initialise page tables.
[S390] Move stfl to system.h and delete duplicated version.
[S390] uaccess_mvcos: #ifdef config dependent code.
[S390] cpu topology: Fix possible deadlock.
[S390] Add topology_core_siblings to topology.h
[S390] cio: Make isc handling more robust.
[S390] remove -traditional
[S390] Automatically detect added cpus.
[S390] smp: Fix locking order.
[S390] Add missing ifndef/define to include/asm-s390/sysinfo.h.
[S390] Move show_regs to traps.c.
[S390] cio: Use strict_strtoul() for attributes.
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git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc
* 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc:
[POWERPC] Fix crashkernel= handling when no crashkernel= specified
[POWERPC] Make emergency stack safe for current_thread_info() use
[POWERPC] spufs: add .gitignore for spu_save_dump.h & spu_restore_dump.h
[POWERPC] spufs: trace spu_acquire_saved events
[POWERPC] spufs: fix marker name for find_victim
[POWERPC] spufs: add marker for destroy_spu_context
[POWERPC] spufs: add sputrace marker parameter names
[POWERPC] spufs: add context switch notification log
[POWERPC] mpc5200: defconfigs for CM5200, Lite5200B, Motion-PRO and TQM5200
[POWERPC] mpc5200: Switch mpc5200 dts files to dts-v1 format
[POWERPC] mpc5200: Fix FEC error handling on FIFO errors
[POWERPC] mpc5200: add Phytec pcm030 board support
[POWERPC] mpc5200: add gpiolib support for mpc5200
[POWERPC] mpc5200: add interrupt type function
[POWERPC] mpc5200: Fix unterminated of_device_id table
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This adds a minimalistic braille screen reader support. This is meant to
be used by blind people e.g. on boot failures or when / cannot be mounted
etc and thus the userland screen readers can not work.
[akpm@linux-foundation.org: fix exports]
Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Cc: Jiri Kosina <jikos@jikos.cz>
Cc: Dmitry Torokhov <dtor@mail.ru>
Acked-by: Alan Cox <alan@redhat.com>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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- Operations are now a shared const function block as with most other Linux
objects
- Introduce wrappers for some optional functions to get consistent behaviour
- Wrap put_char which used to be patched by the tty layer
- Document which functions are needed/optional
- Make put_char report success/fail
- Cache the driver->ops pointer in the tty as tty->ops
- Remove various surplus lock calls we no longer need
- Remove proc_write method as noted by Alexey Dobriyan
- Introduce some missing sanity checks where certain driver/ldisc
combinations would oops as they didn't check needed methods were present
[akpm@linux-foundation.org: fix fs/compat_ioctl.c build]
[akpm@linux-foundation.org: fix isicom]
[akpm@linux-foundation.org: fix arch/ia64/hp/sim/simserial.c build]
[akpm@linux-foundation.org: fix kgdb]
Signed-off-by: Alan Cox <alan@redhat.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Cc: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Replace TIF_RESTORE_SIGMASK with TS_RESTORE_SIGMASK and define our own
set_restore_sigmask() function. This saves the costly SMP-safe set_bit
operation, which we do not need for the sigmask flag since TIF_SIGPENDING
always has to be set too.
Signed-off-by: Roland McGrath <roland@redhat.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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TIF_RESTORE_SIGMASK no longer needs to be in the _TIF_WORK_* masks.
Those low bits are scarce. Renumber TIF_RESTORE_SIGMASK to free one up.
Signed-off-by: Roland McGrath <roland@redhat.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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TIF_RESTORE_SIGMASK no longer needs to be in the _TIF_WORK_* masks. Those low
bits are scarce, and are all used up now. Renumber TIF_RESTORE_SIGMASK to
free one up.
Signed-off-by: Roland McGrath <roland@redhat.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Signed-off-by: eric miao <eric.miao@marvell.com>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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This is part of the effort moving peripheral registers outside of pxa-regs.h,
and using ioremap() make it possible the same IP can be re-used on different
processors with different registers space
As a result, the fixed mapping in pxa_map_io() is removed.
The regs-lcd.h can actually moved to where closer to pxafb.c but some of its
bit definitions are directly used by various platform code, though this is not
a good style.
Signed-off-by: eric miao <eric.miao@marvell.com>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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After the PT_IEEE_IP hack has been removed s390 can now use
the common code sys_ptrace function.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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The self referential PT_IEEE_IP ptrace peek & poke calls have been
broken for that last 6 years. For peek the code always returns 0
instead of the last ieee fault and for poke the code does nothing.
Since nobody noticed the code seems to be superfluous. So lets
remove it.
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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Convert s390 to SPARSEMEM and SPARSEMEM_VMEMMAP. We do a select
of SPARSEMEM_VMEMMAP since it is configurable. This is because
SPARSEMEM without SPARSEMEM_VMEMMAP gives us a hell of broken
include dependencies that I don't want to fix.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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This adds hugetlbfs support on System z, using both hardware large page
support if available and software large page emulation on older hardware.
Shared (large) page tables are implemented in software emulation mode,
by using page->index of the first tail page from a compound large page
to store page table information.
Signed-off-by: Gerald Schaefer <geraldsc@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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From: Heiko Carstens <heiko.carstens@de.ibm.com>
From: Carsten Otte <cotte@de.ibm.com>
This lets us use defines for the magic bits in machine flags instead
of using plain numbers all over the place.
In addition on newer machines features/facilities are indicated by the
result of the stfl instruction. So we use these bits instead of trying
to execute new instructions and check wether we get an exception or
not.
Also the mvpg instruction is always available when in zArch mode,
whereas the idte instruction is only available in zArch mode. This
results in some minor optimizations.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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Always use clear_table to initialise page tables. The overlapping
memcpy is just a leftover of a previous version that wasn't fully
converted to clear_table.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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arch/s390/lib/uaccess_mvcos.c:166:
warning: 'strnlen_user_mvcos' defined but not used
arch/s390/lib/uaccess_mvcos.c:186:
warning: 'strncpy_from_user_mvcos' defined but not used
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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When we get a notification that cpu topology changed, we schedule a
work struct which just calls arch_reinit_sched_domains. This function
in turn calls get_online_cpus() which results int the lockdep warning
below.
After all it turnded out that it's not legal to call get_online_cpus()
from the context of a multi-threaded work queue.
It could deadlock this way:
process 0 (events/cpu-x):
-> run_workqueue
-> removes my work_struct from the work queue
-> calls work_struct->fn
-> get_online_cpus()
-> locks on cpu_hotplug.lock since process 1 below is doing cpu hotplug
process 1:
-> cpu_down (for cpu-x)
-> cpu_hotplug_begin (holds cpu_hotplug.lock now)
-> cpu-x dead
-> notifier_call_chain with CPU_DEAD
-> cleanup_workqueue_thread
-> flush_cpu_workqueue (succeeds)
-> kthread_stop for events/cpu-x
-> now kthread_stop waits for my work_struct to complete from within
process 0. -> dead.
A single threaded workqueue wouldn't have such problems, however there is
no such common queue available and it's not worth to create one for the
very rare calls to arch_reinit_sched_domains.
So we just create a kernel thread from our work struct which calls
arch_reinit_sched_domains and are done with it.
Thanks to Oleg Nesterov and Peter Zijlstra for helping me figuring out
that this isn't a false positive lockdep warning:
=======================================================
[ INFO: possible circular locking dependency detected ]
2.6.25-03562-g3dc5063-dirty #12
-------------------------------------------------------
events/3/14 is trying to acquire lock:
(&cpu_hotplug.lock){--..}, at: [<0000000000076094>] get_online_cpus+0x50/0x78
but task is already holding lock:
(topology_work){--..}, at: [<0000000000059cde>] run_workqueue+0x106/0x278
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #2 (topology_work){--..}:
[<000000000006fc74>] __lock_acquire+0x1010/0x111c
[<000000000006fe40>] lock_acquire+0xc0/0xf8
[<0000000000059d48>] run_workqueue+0x170/0x278
[<0000000000059edc>] worker_thread+0x8c/0xf0
[<000000000005f5bc>] kthread+0x68/0xa0
[<000000000001a33e>] kernel_thread_starter+0x6/0xc
[<000000000001a338>] kernel_thread_starter+0x0/0xc
-> #1 (events){--..}:
[<000000000006fc74>] __lock_acquire+0x1010/0x111c
[<000000000006fe40>] lock_acquire+0xc0/0xf8
[<000000000005a23c>] cleanup_workqueue_thread+0x60/0xa8
[<00000000003b2ab8>] workqueue_cpu_callback+0xbc/0x170
[<00000000003bba80>] notifier_call_chain+0x5c/0xa4
[<00000000000655a2>] __raw_notifier_call_chain+0x26/0x38
[<00000000000655e2>] raw_notifier_call_chain+0x2e/0x40
[<0000000000075e00>] cpu_down+0x228/0x31c
[<00000000003b1dd8>] store_online+0x64/0xb8
[<00000000001e7128>] sysdev_store+0x48/0x58
[<0000000000121cd2>] sysfs_write_file+0x126/0x1c0
[<00000000000c1944>] vfs_write+0xb0/0x15c
[<00000000000c20e6>] sys_write+0x56/0x88
[<0000000000027a68>] sys32_write+0x34/0x4c
[<0000000000023f70>] sysc_noemu+0x10/0x16
[<0000000077f3f186>] 0x77f3f186
-> #0 (&cpu_hotplug.lock){--..}:
[<000000000006fa84>] __lock_acquire+0xe20/0x111c
[<000000000006fe40>] lock_acquire+0xc0/0xf8
[<00000000003b701c>] mutex_lock_nested+0xd0/0x364
[<0000000000076094>] get_online_cpus+0x50/0x78
[<000000000003a03e>] arch_reinit_sched_domains+0x26/0x58
[<000000000002700e>] topology_work_fn+0x26/0x34
[<0000000000059d4e>] run_workqueue+0x176/0x278
[<0000000000059edc>] worker_thread+0x8c/0xf0
[<000000000005f5bc>] kthread+0x68/0xa0
[<000000000001a33e>] kernel_thread_starter+0x6/0xc
[<000000000001a338>] kernel_thread_starter+0x0/0xc
other info that might help us debug this:
2 locks held by events/3/14:
#0: (events){--..}, at: [<0000000000059cde>] run_workqueue+0x106/0x278
#1: (topology_work){--..}, at: [<0000000000059cde>] run_workqueue+0x106/0x278
stack backtrace:
CPU: 3 Not tainted 2.6.25-03562-g3dc5063-dirty #12
Process events/3 (pid: 14, task: 000000002fb04038, ksp: 000000002fb0bd70)
0400000000000000 000000002fb0ba40 0000000000000002 0000000000000000
000000002fb0bae0 000000002fb0ba58 000000002fb0ba58 0000000000016488
0000000000000000 000000002fb0bd70 0000000000000000 0000000000000000
000000002fb0ba40 000000000000000c 000000002fb0ba40 000000002fb0bab0
00000000003c99e0 0000000000016488 000000002fb0ba40 000000002fb0ba90
Call Trace:
([<00000000000163fc>] show_trace+0x138/0x158)
[<00000000000164e2>] show_stack+0xc6/0xf8
[<0000000000016624>] dump_stack+0xb0/0xc0
[<000000000006cd36>] print_circular_bug_tail+0xa2/0xb4
[<000000000006fa84>] __lock_acquire+0xe20/0x111c
[<000000000006fe40>] lock_acquire+0xc0/0xf8
[<00000000003b701c>] mutex_lock_nested+0xd0/0x364
[<0000000000076094>] get_online_cpus+0x50/0x78
[<000000000003a03e>] arch_reinit_sched_domains+0x26/0x58
[<000000000002700e>] topology_work_fn+0x26/0x34
[<0000000000059d4e>] run_workqueue+0x176/0x278
[<0000000000059edc>] worker_thread+0x8c/0xf0
[<000000000005f5bc>] kthread+0x68/0xa0
[<000000000001a33e>] kernel_thread_starter+0x6/0xc
[<000000000001a338>] kernel_thread_starter+0x0/0xc
INFO: lockdep is turned off.
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
|
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This exposes the core siblings to user space via sysfs.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
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Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
CC: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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On some smp sysfs store attributes get_online_cpus() may block on
cpu_hotplug.lock, but we hold already smp_cpu_state_mutex. Since the
locking order on cpu hotplug via arch_update_cpu_topology is inverse
this might lead to deadlocks.
So make sure locking order is always the same.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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This is where it should be and we can get rid of some externs
and a static inline function.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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Commit edd8ce67436851a62f99f1d9707b40ea6a8e5323 (Use extended crashkernel
command line on ppc64), changed the logic in reserve_crashkernel()
which deals with the crashkernel= command line option.
This introduced a bug in the case when there is no crashkernel= option,
or it is incorrect. We would fall through and calculate the crash_size
based on the existing values in crashk_res. If both start and end are 0,
the default, we calculate the crash_size as 1 byte - which is wrong.
Rework the logic so that we use crashk_res, regardless of whether it's
set by the command line or via the device tree (see prom.c). Then check
if we have an empty range (end == start), and if so make sure to set
both end and start to zero (this is checked in machine_kexec_64.c). Then
we calculate the crash_size once we know we have a non-zero range.
Finally we always want to warn the user if they specify a base != 32MB,
so remove the special case for that in the command line parsing case.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
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