| Age | Commit message (Collapse) | Author |
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remove the sleep_type heuristics from the core scheduler - scheduling
policy is implemented in the scheduling-policy modules. (and CFS does
not use this type of sleep-type heuristics)
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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add the new load-calculation methods of CFS.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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clean up: move __normal_prio() in head of normal_prio().
no code changed.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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cleanup: move dequeue/enqueue_task() to a more logical place, to
not split up __normal_prio()/normal_prio().
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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move resched_task()/resched_cpu() into the 'public interfaces'
section of sched.c, for use by kernel/sched_fair/rt/idletask.c
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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remove the SleepAVG field from /proc/<pid>/status, as
with the removal of the sleep-average code this value
no longer makes sense.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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clean up the rt priority macros, pointed out by Andrew Morton.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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add the set_task_cfs_rq() abstraction needed by CONFIG_FAIR_GROUP_SCHED.
(not activated yet)
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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update the posix-cpu-timers code to use CFS's CPU accounting information.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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add rq_clock()/__rq_clock(), a robust wrapper around sched_clock(),
used by CFS. It protects against common type of sched_clock() problems
(caused by hardware): time warps forwards and backwards.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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add the CFS rq data types to sched.c.
(the old scheduler fields are still intact, they are removed
by a later patch)
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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add the CFS data types to sched.h.
(the old scheduler is still fully intact.)
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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add kernel/sched_idletask.c - which implements the idle thread
scheduling class. This further simplifies sched.c (under CFS),
for example a number of 'if (p == rq->idle)' type of special-cases
can be removed from sched.c, and schedule() gets simpler too.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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add kernel/sched_rt.c: SCHED_FIFO/SCHED_RR support. The behavior
and semantics of SCHED_FIFO/SCHED_RR tasks is unchanged.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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add kernel/sched_fair.c - which implements the bulk of CFS's
behavioral changes for SCHED_OTHER tasks.
see Documentation/sched-design-CFS.txt about details.
Authors:
Ingo Molnar <mingo@elte.hu>
Dmitry Adamushko <dmitry.adamushko@gmail.com>
Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
Mike Galbraith <efault@gmx.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
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increase SMP-nice's resolution. This is needed by CFS to
implement SCHED_IDLE and cleaned up nice level support.
no behavioral changes.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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create sched_stats.h and move sched.c schedstats code into it.
This cleans up sched.c a bit.
no code changes are caused by this patch.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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add the init_idle_bootup_task() callback to the bootup thread,
unused at the moment. (CFS will use it to switch the scheduling
class of the boot thread to the idle class)
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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add in_atomic_preempt_off() - debugging helper that will
simplify schedule().
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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remove sched_exit(): the elaborate dance of us trying to recover
timeslices given to child tasks never really worked.
CFS does not need it either.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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uninline set_task_cpu(): CFS will add more code to it.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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the SMP load-balancer uses the boot-time migration-cost estimation
code to attempt to improve the quality of balancing. The reason for
this code is that the discrete priority queues do not preserve
the order of scheduling accurately, so the load-balancer skips
tasks that were running on a CPU 'recently'.
this code is fundamental fragile: the boot-time migration cost detector
doesnt really work on systems that had large L3 caches, it caused boot
delays on large systems and the whole cache-hot concept made the
balancing code pretty undeterministic as well.
(and hey, i wrote most of it, so i can say it out loud that it sucks ;-)
under CFS the same purpose of cache affinity can be achieved without
any special cache-hot special-case: tasks are sorted in the 'timeline'
tree and the SMP balancer picks tasks from the left side of the
tree, thus the most cache-cold task is balanced automatically.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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this patch adds the SCHED_IDLE policy to sched.h.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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enum idle_type (used by the load-balancer) clashes with the
SCHED_IDLE name that we want to introduce. 'CPU_IDLE' instead
of 'SCHED_IDLE' is more descriptive as well.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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Woo-hoo. I'm sure somebody will report a "this doesn't compile, and
I have a new root exploit" five minutes after release, but it still
feels good ;)
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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* master.kernel.org:/pub/scm/linux/kernel/git/bart/ide-2.6:
qd65xx: fix PIO mode selection
sis5513: adding PCI-ID
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Commit 1c710c896eb461895d3c399e15bb5f20b39c9073 added the utimensat()
system call, but didn't handle the case of checking for the writability
of the target right, when the target was a file descriptor, not a
filename.
We cannot use vfs_permission(MAY_WRITE) for that case, and need to
simply check whether the file descriptor is writable. The oops from
using the wrong function was noticed and narrowed down by Markus
Trippelsdorf.
Cc: Ulrich Drepper <drepper@redhat.com>
Cc: Markus Trippelsdorf <markus@trippelsdorf.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Al Viro <viro@ftp.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Fix a post-2.6.21 regression.
read_cache_page_async() has two invocations of mark_page_accessed() which will
launch pages right onto the active list.
Remove the first one, keeping the latter one. This avoids marking unwanted
pages active (in the retry loop).
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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PIO4 is a maximum PIO mode supported by a driver. Using "255" as a max_mode
argument to ide_get_best_pio_mode() could result in wrong timings being used
by a driver (for "pio" equal to 5) or OOPS (for "pio" values > 5 && < 255).
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Reviewed-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
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The SiS966 has one additional PCI-ID 1180.
If the chipset is using this PCI-ID, the primary channel is connected to the
first PATA-port. The secondary channel is connected to SATA-ports in IDE
emulation mode. The legacy IO-ports are used.
The including of the PCI-ID into pata_sis is not sufficient, because the legacy
driver in drivers/ide is initialized before pata_sis.
Signed-off-by: Uwe Koziolek <uwe.koziolek@gmx.net>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
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The dependency of DLM on SYSFS got lost in
commit 6ed7257b46709e87d79ac2b6b819b7e0c9184998 resulting in the
following compile error with CONFIG_DLM=y, CONFIG_SYSFS=n:
<-- snip -->
...
LD .tmp_vmlinux1
fs/built-in.o: In function `dlm_lockspace_init':
/home/bunk/linux/kernel-2.6/linux-2.6.22-rc6-mm1/fs/dlm/lockspace.c:231: undefined reference to `kernel_subsys'
fs/built-in.o: In function `configfs_init':
/home/bunk/linux/kernel-2.6/linux-2.6.22-rc6-mm1/fs/configfs/mount.c:143: undefined reference to `kernel_subsys'
make[1]: *** [.tmp_vmlinux1] Error 1
<-- snip -->
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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The printk level in this printk is bogus, as the previous printk
didn't have a terminating \n resulting in ..
Intel E7520/7320/7525 detected.<6>Disabling irq balancing and affinity
It also never printed a \n at all in the case where we didn't do
the quirk.
Change it to only make noise if it actually does something useful.
Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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This patch fixes the following 2.6.22 regression with CONFIG_KALLSYMS=n:
<-- snip -->
...
CC arch/m32r/kernel/traps.o
In file included from /home/bunk/linux/kernel-2.6/linux-2.6.22-rc6-mm1/arch/m32r/kernel/traps.c:14:
/home/bunk/linux/kernel-2.6/linux-2.6.22-rc6-mm1/include/linux/kallsyms.h: In function 'lookup_symbol_name':
/home/bunk/linux/kernel-2.6/linux-2.6.22-rc6-mm1/include/linux/kallsyms.h:66: error: 'ERANGE' undeclared (first use in this function)
/home/bunk/linux/kernel-2.6/linux-2.6.22-rc6-mm1/include/linux/kallsyms.h:66: error: (Each undeclared identifier is reported only once
/home/bunk/linux/kernel-2.6/linux-2.6.22-rc6-mm1/include/linux/kallsyms.h:66: error: for each function it appears in.)
/home/bunk/linux/kernel-2.6/linux-2.6.22-rc6-mm1/include/linux/kallsyms.h: In function 'lookup_symbol_attrs':
/home/bunk/linux/kernel-2.6/linux-2.6.22-rc6-mm1/include/linux/kallsyms.h:71: error: 'ERANGE' undeclared (first use in this function)
make[2]: *** [arch/m32r/kernel/traps.o] Error 1
<-- snip -->
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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When cleaning up HIDP sessions, we currently close the ACL connection
before deregistering the input device. Closing the ACL connection
schedules a workqueue to remove the associated objects from sysfs, but
the input device still refers to them -- and if the workqueue happens to
run before the input device removal, the kernel will oops when trying to
look up PHYSDEVPATH for the removed input device.
Fix this by deregistering the input device before closing the
connections.
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Acked-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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kmem_cache_open is static. EXPORT_SYMBOL was leftover from some earlier
time period where kmem_cache_open was usable outside of slub.
(Fixes powerpc build error)
Signed-off-by: Chrsitoph Lameter <clameter@sgi.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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davem kindly moved the list from osdl to vger.
Signed-of-by: maximilian attems <max@stro.at>
Cc: Alexey Dobriyan <adobriyan@gmail.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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Writing to MSR 0x51400017 forces a hard reset on CS5536-based machines,
this has the reboot fixup do just that if such a board is detected.
Acked-by: Jordan Crouse <jordan.crouse@amd.com>
Signed-off-by: Andres Salomon <dilinger@debian.org>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
* 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6:
[NETPOLL]: Fixups for 'fix soft lockup when removing module'
[NET]: net/core/netevent.c should #include <net/netevent.h>
[NETFILTER]: nf_conntrack_h323: add checking of out-of-range on choices' index values
[NET] skbuff: remove export of static symbol
SCTP: Add scope_id validation for link-local binds
SCTP: Check to make sure file is valid before setting timeout
SCTP: Fix thinko in sctp_copy_laddrs()
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* 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus:
[MIPS] Fix scheduling latency issue on 24K, 34K and 74K cores
[MIPS] Add macros to encode processor revisions.
[MIPS] RM7000: Enable ICACHE_REFILLS_WORKAROUND_WAR.
[MIPS] SMTC: Fix cut'n'paste bug in Kconfig.debug
[MIPS] Change libgcc-style functions from lib-y to obj-y
[MIPS] Fix timer/performance interrupt detection
[MIPS] AP/SP: Avoid triggering the 34K E125 performance issue
[MIPS] 64-bit TO_PHYS_MASK macro for RM9000 processors
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Line up the vmstat_text with zone_stat_item
enum zone_stat_item {
/* First 128 byte cacheline (assuming 64 bit words) */
NR_FREE_PAGES,
NR_INACTIVE,
NR_ACTIVE,
We current have nr_active and nr_inactive reversed.
[ "OK with patch, though using initializers canbe handy to prevent such
things in future:
static const char * const vmstat_text[] = {
[NR_FREE_PAGES] = "nr_free_pages",
..."
- Alexey ]
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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In 7d12e780e003f93433d49ce78cfedf4b4c52adc5 David Howells performed
this evolution:
"IRQ: Maintain regs pointer globally rather than passing to IRQ handlers"
He correctly updated many of the function definitions that were using this
extra regs pointer parameter but forgot to update some caller sites of
those functions. The reason the modifications was not properly done on all
drivers is that some drivers were rarely compiled because they are for
AMIGA, or that some code sites were inside #ifdefs where the option is not
set or inside #if 0.
Here is the semantic patch that found the occurences
and fixed the problem.
@ rule1 @
identifier fn;
identifier irq, dev_id;
typedef irqreturn_t;
@@
static irqreturn_t fn(int irq, void *dev_id)
{
...
}
@@
identifier rule1.fn;
expression E1, E2, E3;
@@
fn(E1, E2
- ,E3
)
Signed-off-by: Yoann Padioleau <padator@wanadoo.fr>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jeff Garzik <jeff@garzik.org>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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o Commit 1833d6bc72893265f22addd79cf52e6987496e0f broke the build if
compiled with CONFIG_ES7000=y and CONFIG_X86_GENERICARCH=n
arch/i386/kernel/built-in.o(.init.text+0x4fa9): In function `acpi_parse_madt':
: undefined reference to `acpi_madt_oem_check'
arch/i386/kernel/built-in.o(.init.text+0x7406): In function `smp_read_mpc':
: undefined reference to `mps_oem_check'
arch/i386/kernel/built-in.o(.init.text+0x8990): In function
`connect_bsp_APIC':
: undefined reference to `enable_apic_mode'
make: *** [.tmp_vmlinux1] Error 1
o Fix the build issue. Provided the definitions of missing functions.
o Don't have ES7000 machine. Only compile tested.
Cc: Len Brown <lenb@kernel.org>
Cc: Natalie Protasevich <protasnb@gmail.com>
Cc: Roland Dreier <rolandd@cisco.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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When we enable the SMCf010 IR device, the Toshiba Portege 4000 BIOS claims
the device is working, but it really isn't configured correctly. The BIOS
*will* configure it, but only if we call _SRS after (1) reversing the order
of the SIR and FIR I/O port regions and (2) changing the IRQ from
active-high to active-low.
This patch addresses the 2.6.22 regression:
"no irda0 interface (2.6.21 was OK), smsc does not find chip"
I tested this on a Portege 4000. The smsc-ircc2 driver correctly detects
the device, and "irattach irda0 -s && irdadump" shows transmitted and
received packets.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Cc: Andrey Borzenkov <arvidjaar@mail.ru>
Cc: Samuel Ortiz <samuel@sortiz.org>
Cc: "Linus Walleij (LD/EAB)" <linus.walleij@ericsson.com>
Cc: Michal Piotrowski <michal.k.k.piotrowski@gmail.com>
Cc: Adam Belay <ambx1@neo.rr.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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When calling a semctl(IPC_STAT) without IPC_64 the check if the memory is
unevaluated. This patch fixes this.
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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A bug in headers_install for ARCH=x86_64 yields an asm/ directory full of
files all of which are using the same #ifdef guard, "__ASM_STUB_" with no
postfix. So the second and later asm files #included in the same C file
(often through standard headers like ioctl.h) yields no symbols.
Strangeness with the Ubuntu 'tell me if I support something that's not
explcitly mentioned in POSIX, and I'll strip it out' shell, I believe.
We don't need the 'export' but we do need a semicolon at the end of the
FNAME line:
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Rob Landley <rob@landley.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Processors synchronization in set_mtrr requires the .gate field to be set
after .count field is properly initialized. Without an explicit barrier,
the compiler was reordering those memory stores. That was sometimes
causing a processor (in ipi_handler) to see the .gate change and decrement
.count before the latter is set by set_mtrr() (which then hangs in a
infinite loop with irqs disabled).
Signed-off-by: Loic Prylli <loic@myri.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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The commit 635cf99a80f4ebee59d70eb64bb85ce829e4591f introduced a
regression. Executing a ptrace single step after certain int80
accesses will infinitely loop and never advance the PC.
The TIF_SINGLESTEP check should be done on the return from the syscall
and not before it.
I loops on each single step on the pop right after the int80 which writes out
to the console. At that point you can issue as many single steps as you want
and it will not advance any further.
The test case is below:
/* Test whether singlestep through an int80 syscall works.
*/
#define _GNU_SOURCE
#include <stdio.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/ptrace.h>
#include <sys/wait.h>
#include <sys/mman.h>
#include <asm/user.h>
#include <string.h>
static int child, status;
static struct user_regs_struct regs;
static void do_child()
{
char str[80] = "child: int80 test\n";
ptrace(PTRACE_TRACEME, 0, 0, 0);
kill(getpid(), SIGUSR1);
write(fileno(stdout),str,strlen(str));
asm ("int $0x80" : : "a" (20)); /* getpid */
}
static void do_parent()
{
unsigned long eip, expected = 0;
again:
waitpid(child, &status, 0);
if (WIFEXITED(status) || WIFSIGNALED(status))
return;
if (WIFSTOPPED(status)) {
ptrace(PTRACE_GETREGS, child, 0, ®s);
eip = regs.eip;
if (expected)
fprintf(stderr, "child stop @ %08lx, expected %08lx %s\n",
eip, expected,
eip == expected ? "" : " <== ERROR");
if (*(unsigned short *)eip == 0x80cd) {
fprintf(stderr, "int 0x80 at %08x\n", (unsigned int)eip);
expected = eip + 2;
} else
expected = 0;
ptrace(PTRACE_SINGLESTEP, child, NULL, NULL);
}
goto again;
}
int main(int argc, char * const argv[])
{
child = fork();
if (child)
do_parent();
else
do_child();
return 0;
}
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: <stable@kernel.org>
Cc: Chuck Ebbert <76306.1226@compuserve.com>
Acked-by: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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elf_core_dump() supports dumping arch specific ELF notes, via the #define
ELF_CORE_WRITE_EXTRA_NOTES. Currently the only user of this is the powerpc
spu coredump code.
There is a bug in the handling of foffset WRT the arch notes, which causes
us to erroneously increment foffset by the size of the arch notes, leaving
a block of zeroes in the file, and causing all subsequent data in the file
to be at <supposed position> + <arch note size>. eg:
LOAD 0x050000 0x00100000 0x00000000 0x20000 0x20000 R E 0x10000
Tells us we should have a chunk of data at 0x50000. The truth is the data
is at 0x90dbc = 0x50000 + 0x40dbc (the size of the arch notes).
This bug prevents gdb from reading the core file correctly.
The simplest fix is to simply remember the size of the arch notes, and add
it to foffset after we've written the arch notes. The only drawback is
that if the arch code doesn't write as many bytes as it said it would, we
end up with a broken core dump again. For now I think that's a reasonable
requirement.
Tested on a Cell blade, gdb no longer complains about the core file being
bogus.
While I'm here I should point out that the spu coredump code does not work
if we're dumping to a pipe - we'll have to wait for 23 to fix that.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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The idle loop goes to sleep using the WAIT instruction if !need_resched().
This has is suffering from from a race condition that if if just after
need_resched has returned 0 an interrupt might set TIF_NEED_RESCHED but
we've just completed the test so go to sleep anyway. This would be
trivial to fix by just disabling interrupts during that sequence as in:
local_irq_disable();
if (!need_resched())
__asm__("wait");
local_irq_enable();
but the processor architecture leaves it undefined if a processor calling
WAIT with interrupts disabled will ever restart its pipeline and indeed
some processors have made use of the freedom provided by the architecture
definition. This has been resolved and the Config7.WII bit indicates that
the use of WAIT is safe on 24K, 24KE and 34K cores. It also is safe on
74K starting revision 2.1.0 so enable the use of WAIT with interrupts
disabled for 74K based on a c0_prid of at least that.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
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Older processors used to encode processor version and revision in two
4-bit bitfields, the 4K seems to simply count up and even newer MTI cores
have switched to use the 8-bits as 3:3:2 bitfield with the last field as
the patch number.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
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