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At present, we can hit the BUG_ON in __spu_update_sched_info by reading
the regs file of a context between two calls to spu_run. The
spu_release_saved called by spufs_regs_read() is resulting in the (now
non-runnable) context being placed back on the run queue, so the next
call to spu_run ends up in the bug condition.
This change uses the SPU_SCHED_SPU_RUN flag to only reschedule a context
if it's still in spu_run().
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
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commit 4ef11014 introduced a usage of SCHED_IDLE to detect when
a context is within spu_run.
Instead of SCHED_IDLE (which has other meaning), add a flag to
sched_flags to tell if a context should be running.
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
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master.kernel.org:/pub/scm/linux/kernel/git/arnd/cell-2.6 into merge
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The only tricky part is we need to adjust the PTE insertion loop to
cater for holes in the page table. The PTEs for each segment start on
a 4K boundary, so with 16M pages we have 16 PTEs per segment and then
a gap to the next 4K page boundary.
It might be possible to allocate the PTEs for each segment separately,
saving the memory currently filling the gaps. However we'd need to
check that's OK with the hardware, and that it actually saves memory.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
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Make some preliminary changes to cell_iommu_alloc_ptab() to allow it to
take the page size as a parameter rather than assuming IOMMU_PAGE_SIZE.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
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We use n_pte_pages to calculate the stride through the page tables, but
we also use it to set the NPPT value in the segment table entry. That is
defined as the number of 4K pages per segment, so we should calculate
it as such regardless of the IOMMU page size.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
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separately
Currently the cell IOMMU code allocates the entire IOMMU page table in a
contiguous chunk. This is nice and tidy, but for machines with larger
amounts of RAM the page table allocation can fail due to it simply being
too large.
So split the segment table and page table setup routine, and arrange to
have the dynamic and fixed page tables allocated separately.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
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There's no need to allocate the pad page unless we're going to actually
use it - so move the allocation to where we know we're going to use it.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
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The cell IOMMU code no longer needs to save the pte_offset variable
separately, it is incorporated into tbl->it_offset.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
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The cell IOMMU tce build and free routines use pte_offset to convert
the index passed from the generic IOMMU code into a page table offset.
This takes into account the SPIDER_DMA_OFFSET which sets the top bit
of every DMA address.
However it doesn't cater for the IOMMU window starting at a non-zero
address, as the base of the window is not incorporated into pte_offset
at all.
As it turns out tbl->it_offset already contains the value we need, it
takes into account the base of the window and also pte_offset. So use
it instead!
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
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It's called the fixed mapping, not the static mapping.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
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Ulrich Weigand has found that the hardware watchpoints on cell were not
working back in November :
http://ozlabs.org/pipermail/linuxppc-dev/2007-November/046135.html
This patch sets them during initialization.
Signed-off-by: Jens Osterkamp <jens@de.ibm.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
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This moves the private DABRX definitions for celleb from beat.h to
reg.h to make them usable for all.
Signed-off-by: Jens Osterkamp <jens@de.ibm.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
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This patch enables OProfile callgraph support for the Cell processor. The
original code was just calling a function to add the PC value, now it will
call a function that first checks the callgraph depth. Callgraph is already
enabled on the other Power platforms.
Signed-off-by: Bob Nelson <rrnelson@us.ibm.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
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git://git.kernel.org/pub/scm/linux/kernel/git/jk/spufs into merge
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master.kernel.org:/pub/scm/linux/kernel/git/jwboyer/powerpc-4xx into merge
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git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6:
firewire: fix crash in automatic module unloading
firewire: potentially invalid pointers used in fw_card_bm_work
firewire: fw-sbp2: better fix for NULL pointer dereference in scsi_remove_device
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"modprobe firewire-ohci; sleep .1; modprobe -r firewire-ohci" used to
result in crashes like this:
BUG: unable to handle kernel paging request at ffffffff8807b455
IP: [<ffffffff8807b455>]
PGD 203067 PUD 207063 PMD 7c170067 PTE 0
Oops: 0010 [1] PREEMPT SMP
CPU 0
Modules linked in: i915 drm cpufreq_ondemand acpi_cpufreq freq_table applesmc input_polldev led_class coretemp hwmon eeprom snd_seq_oss snd_seq_midi_event snd_seq snd_seq_device snd_pcm_oss snd_mixer_oss button thermal processor sg snd_hda_intel snd_pcm snd_timer snd snd_page_alloc sky2 i2c_i801 rtc [last unloaded: crc_itu_t]
Pid: 9, comm: events/0 Not tainted 2.6.25-rc2 #3
RIP: 0010:[<ffffffff8807b455>] [<ffffffff8807b455>]
RSP: 0018:ffff81007dcdde88 EFLAGS: 00010246
RAX: ffff81007dc95040 RBX: ffff81007dee5390 RCX: 0000000000005e13
RDX: 0000000000008c8b RSI: 0000000000000001 RDI: ffff81007dee5388
RBP: ffff81007dc5eb40 R08: 0000000000000002 R09: ffffffff8022d05c
R10: ffffffff8023b34c R11: ffffffff8041a353 R12: ffff81007dee5388
R13: ffffffff8807b455 R14: ffffffff80593bc0 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffffffff8055a000(0000) knlGS:0000000000000000
CS: 0010 DS: 0018 ES: 0018 CR0: 000000008005003b
CR2: ffffffff8807b455 CR3: 0000000000201000 CR4: 00000000000006e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process events/0 (pid: 9, threadinfo ffff81007dcdc000, task ffff81007dc95040)
Stack: ffffffff8023b396 ffffffff88082524 0000000000000000 ffffffff8807d9ae
ffff81007dc5eb40 ffff81007dc9dce0 ffff81007dc5eb40 ffff81007dc5eb80
ffff81007dc9dce0 ffffffffffffffff ffffffff8023be87 0000000000000000
Call Trace:
[<ffffffff8023b396>] ? run_workqueue+0xdf/0x1df
[<ffffffff8023be87>] ? worker_thread+0xd8/0xe3
[<ffffffff8023e917>] ? autoremove_wake_function+0x0/0x2e
[<ffffffff8023bdaf>] ? worker_thread+0x0/0xe3
[<ffffffff8023e813>] ? kthread+0x47/0x74
[<ffffffff804198e0>] ? trace_hardirqs_on_thunk+0x35/0x3a
[<ffffffff8020c008>] ? child_rip+0xa/0x12
[<ffffffff8020b6e3>] ? restore_args+0x0/0x3d
[<ffffffff8023e68a>] ? kthreadd+0x14c/0x171
[<ffffffff8023e68a>] ? kthreadd+0x14c/0x171
[<ffffffff8023e7cc>] ? kthread+0x0/0x74
[<ffffffff8020bffe>] ? child_rip+0x0/0x12
Code: Bad RIP value.
RIP [<ffffffff8807b455>]
RSP <ffff81007dcdde88>
CR2: ffffffff8807b455
---[ end trace c7366c6657fe5bed ]---
Note that this crash happened _after_ firewire-core was unloaded. The
shared workqueue tried to run firewire-core's device initialization jobs
or similar jobs.
The fix makes sure that firewire-ohci and hence firewire-core is not
unloaded before all device shutdown jobs have been completed. This is
determined by the count of device initializations minus device releases.
Also skip useless retries in the node initialization job if the node is
to be shut down.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: Jarod Wilson <jwilson@redhat.com>
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The bus management workqueue job was in danger to dereference NULL
pointers. Also, after having temporarily lifted card->lock, a few node
pointers and a device pointer may have become invalid.
Add NULL pointer checks and get the necessary references. Also, move
card->local_node out of fw_card_bm_work's sight during shutdown of the
card.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: Jarod Wilson <jwilson@redhat.com>
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Patch "firewire: fw-sbp2: fix NULL pointer deref. in scsi_remove_device"
had the unintended effect that firewire-sbp2 could not be unloaded
anymore until all SBP-2 devices were unplugged.
We now fix the NULL pointer bug by reacquiring a reference to the sdev
instead of holding a reference to the sdev (and to the module) all the
time.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Tested-by: Jarod Wilson <jwilson@redhat.com>
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Hi,
While we are looking at the printk issue, I see that its printk'ing the EOE
(end of event) records which is really not something that we need in syslog.
Its really intended for the realtime audit event stream handled by the audit
daemon. So, lets avoid printk'ing that record type.
Signed-off-by: Steve Grubb <sgrubb@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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On the latest kernels if one was to load about 15 rules, set the failure
state to panic, and then run service auditd stop the kernel will panic.
This is because auditd stops, then the script deletes all of the rules.
These deletions are sent as audit messages out of the printk kernel
interface which is already known to be lossy. These will overun the
default kernel rate limiting (10 really fast messages) and will call
audit_panic(). The same effect can happen if a slew of avc's come
through while auditd is stopped.
This can be fixed a number of ways but this patch fixes the problem by
just not panicing if auditd is not running. We know printk is lossy and
if the user chooses to set the failure mode to panic and tries to use
printk we can't make any promises no matter how hard we try, so why try?
At least in this way we continue to get lost message accounting and will
eventually know that things went bad.
The other change is to add a new call to audit_log_lost() if auditd
disappears. We already pulled the skb off the queue and couldn't send
it so that message is lost. At least this way we will account for the
last message and panic if the machine is configured to panic. This code
path should only be run if auditd dies for unforeseen reasons. If
auditd closes correctly audit_pid will get set to 0 and we won't walk
this code path.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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Fix the following compiler warning by using "%zu" as defined in C99.
CC kernel/auditsc.o
kernel/auditsc.c: In function 'audit_log_single_execve_arg':
kernel/auditsc.c:1074: warning: format '%ld' expects type 'long int', but
argument 4 has type 'size_t'
Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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git://git.kernel.org/pub/scm/linux/kernel/git/jgarzik/libata-dev
* 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jgarzik/libata-dev:
[libata] wrap kmap_atomic(KM_IRQ0) with local_irq_save/restore()
sata_svw: Add support for HT1100 SATA controller
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Interrupts must be disabled if using kmap_atomic(KM_IRQ0), but that was
not the case in a few code paths coming directly from ATA driver
interrupt handlers (which use spin_lock rather than spin_lock_irqsave).
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
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* 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm:
[ARM] 4843/1: Add GCR_CLKBPB for PXA3xx
[ARM] 4842/1: pxa: remove redundant IRQ saving/restoring in clk_pxa3xx_cken_*
[ARM] 4841/1: pxa: fix typo in LCD platform data definition code for zylonite
[ARM] 4840/1: pxa: fix the typo in get_irqnr_and_base
[ARM] 4839/1: fixes kernel Oops in /dev/mem device driver for memory map with PHYS_OFF
[ARM] eliminate MODULE_PARM() usage
[ARM] 4838/1: Fix kexec for SA1100 machines
[ARM] 4837/1: make __get_unaligned_*() return unsigned types
[ARM] 4836/1: Make ATAGS_PROC depend on KEXEC
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The PXA3xx AC97 controller has an additional control bit GCR_CLKBPB
which must be used during cold reset.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: eric miao <eric.miao@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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This is unnecessary since it is already protected by
spin_lock_irq{save, restore} in clock.c.
Signed-off-by: eric miao <eric.miao@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Signed-off-by: eric miao <eric.miao@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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This typo causes the incorrect calculation of the IRQ numbers
in the ICIP2 registers.
Signed-off-by: eric miao <eric.miao@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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with PHYS_OFF
"cat /dev/mem" may cause kernel Oops for boards with PHYS_OFFSET != 0
because character device is mapped to addresses starting from zero
and there is no protection against such situation.
Patch just add this.
Signed-off-by: Alexandre Rusev <arusev@ru.mvista.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Convert debug-only (and removed) MODULE_PARM() to module_param().
Compiles cleanly (with DEBUG=1).
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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This patch sets KEXEC_CONTROL_MEMORY_LIMIT to (-1)UL. As the value is
compared with physical addresses TASK_SIZE makes no sense. Machines
where the RAM addresses start above TASK_SIZE kexecs eats all memory
and crashes the kernel without this patch.
Signed-off-by: Thomas Kunze <thommycheck@gmx.de>
Acked-by: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Eric Sandeen tracked an XFS on ARM corruption bug down to a function
under fs/xfs/ involving some get_unaligned() calls on u64 pointers.
As it turns out, calling ARM's get_unaligned() on a u64 pointer
pointing to the following byte sequence:
80 81 82 83 84 85 86 87
would return ffffffff83828180 (LE mode.) This turns out to be
because of implicit u8 -> int promotion in ARM's implementation of
various helpers for get_unaligned(), causing them to accidentally
return signed instead of unsigned values, which in turn caused the
subsequent casts to unsigned long long in __get_unaligned_8_[bl]e()
to sign-extend the lower words.
Fix by casting the return values of __get_unaligned_[24]_[bl]e()
to unsigned int.
Cc: Eric Sandeen <sandeen@sandeen.net>
Cc: Rabeeh Khoury <rabeeh@marvell.com>
Cc: Nicolas Pitre <nico@marvell.com>
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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On Wed, Feb 20, 2008 at 11:50:33AM +0100, Guennadi Liakhovetski wrote:
> arch/arm/kernel/atags.c uses for some reason the
> KEXEC_BOOT_PARAMS_SIZE macro, which is only defined if CONFIG_KEXEC
> is set. So, either this macro should be defined always, or another
> macro should be used, or ATAGS_PROC should depend on KEXEC.
As the procfs export of ATAGS is not meant as a stable, general purpose
ABI it shouldn't be an independent, general configuration option.
This patch make ATAGS_PROC depend on KEXEC
Signed-off-by: Uli Luckas <u.luckas@road.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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This patch fixes a potentially invalid access to a per-CPU variable in
rcu_process_callbacks().
This per-CPU access needs to be done in such a way as to guarantee that
the code using it cannot move to some other CPU before all uses of the
value accessed have completed. Even though this code is currently only
invoked from softirq context, which currrently cannot migrate to some
other CPU, life would be better if this code did not silently make such
an assumption.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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This fixes a oops encountered when doing hibernate/resume in presence of
PREEMPT_RCU.
The problem was that the code failed to disable preemption when
accessing a per-CPU variable. This is OK when called from code that
already has preemption disabled, but such is not the case from the
suspend/resume code path.
Reported-by: Dave Young <hidave.darkstar@gmail.com>
Tested-by: Dave Young <hidave.darkstar@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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* git://git.kernel.org/pub/scm/linux/kernel/git/mingo/linux-2.6-sched:
softlockup: fix task state setting
rcu: add support for dynamic ticks and preempt rcu
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Fix 32-on-64 pvops kernel:
we don't want userspace using syscall/sysenter, even if the hypervisor
supports it, so mask it out from CPUID.
Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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The 2.6.25 ptrace_bts_config structure in asm-x86/ptrace-abi.h
is defined with u32 types:
#include <asm/types.h>
/* configuration/status structure used in PTRACE_BTS_CONFIG and
PTRACE_BTS_STATUS commands.
*/
struct ptrace_bts_config {
/* requested or actual size of BTS buffer in bytes */
u32 size;
/* bitmask of below flags */
u32 flags;
/* buffer overflow signal */
u32 signal;
/* actual size of bts_struct in bytes */
u32 bts_size;
};
#endif
But u32 is only accessible in asm-x86/types.h if __KERNEL__,
leading to compile errors when ptrace.h is included from
user-space. The double-underscore versions that are exported
to user-space in asm-x86/types.h should be used instead.
Signed-off-by: Dave Anderson <anderson@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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revert the BTS ptrace extension for now.
based on general objections from Roland McGrath:
http://lkml.org/lkml/2008/2/21/323
we'll let the BTS functionality cook some more and re-enable
it in v2.6.26. We'll leave the dead code around to help the
development of this code.
(X86_BTS is not defined at the moment)
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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avoid over-eager large page splitup.
When the target area needs to be split or is split already (ioremap)
then the current code enforces the split of large mappings in the alias
regions even if we could avoid it.
Use a separate variable processed in the cpa_data structure to carry
the number of pages which have been processed instead of reusing the
numpages variable. This keeps numpages intact and gives the alias code
a chance to keep large mappings intact.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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delay the removal of this symbol export by one more kernel release,
giving external modules such as VirtualBox a chance to stop using it.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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Jan Beulich noticed it during code review that if a driver's ioremap()
fails (say due to -ENOMEM) then we might leak the struct vm_area.
Free it properly.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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Priit Laes discovered that the sed command processing nm output was
sensitive to locale settings. This was addressed in commit
03994f01e8b72b3d01fd3d09d1cc7c9f421a727c by using [:alnum:] in place of
[a-zA-Z0-9].
But that solution too is locale-dependent and may not always match
the identifiers it needs to. The better fix is just to run sed et al
with a fixed locale setting in all builds.
Signed-off-by: Roland McGrath <roland@redhat.com>
CC: Priit Laes <plaes@plaes.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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a recent fix:
commit ce28b9864b853803320c3f1d8de1b81aa4120b14
Author: Thomas Gleixner <tglx@linutronix.de>
Date: Wed Feb 20 23:57:30 2008 +0100
x86: fix vsyscall wreckage
removed the broken /kernel/vsyscall64 handler completely.
This triggers the following debug check:
sysctl table check failed: /kernel/vsyscall64 No proc_handler
Restore the sane part of the proc handler.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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I recently stumbled upon a problem in the support for huge pages. If a
program using huge pages does not explicitly unmap them, they remain
mapped (and therefore, are lost) after the program exits.
I observed that the free huge page count in /proc/meminfo decreased when
running my program, and it did not increase after the program exited.
After running the program a few times, no more huge pages could be
allocated.
The reason for this seems to be that the x86 pmd_bad and pud_bad
consider pmd/pud entries having the PSE bit set invalid. I think there
is nothing wrong with this bit being set, it just indicates that the
lowest level of translation has been reached. This bit has to be (and
is) checked after the basic validity of the entry has been checked, like
in this fragment from follow_page() in mm/memory.c:
if (pmd_none(*pmd) || unlikely(pmd_bad(*pmd)))
goto no_page_table;
if (pmd_huge(*pmd)) {
BUG_ON(flags & FOLL_GET);
page = follow_huge_pmd(mm, address, pmd, flags & FOLL_WRITE);
goto out;
}
Note that this code currently doesn't work as intended if the pmd refers
to a huge page, the pmd_huge() check can not be reached if the page is
huge.
Extending pmd_bad() (and, for future 1GB page support, pud_bad()) to
allow for the PSE bit being set fixes this. For similar reasons,
allowing the NX bit being set is necessary, too. I have seen huge pages
having the NX bit set in their pmd entry, which would cause the same
problem.
Signed-Off-By: Hans Rosenfeld <hans.rosenfeld@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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Fix a kernel bug (vmware boot problem) reported by Tomasz Grobelny,
which occurs with certain .config variants and gccs.
The x86 TLS cleanup in commit efd1ca52d04d2f6df337a3332cee56cd60e6d4c4
made the sys_set_thread_area and sys_get_thread_area functions ripe for
tail call optimization. If the compiler chooses to use it for them, it
can clobber the user trap frame because these are asmlinkage functions.
Reported-by: Tomasz Grobelny <tomasz@grobelny.oswiecenia.net>
Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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kthread_stop() can be called when a 'watchdog' thread is executing after
kthread_should_stop() but before set_task_state(TASK_INTERRUPTIBLE).
Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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The PREEMPT-RCU can get stuck if a CPU goes idle and NO_HZ is set. The
idle CPU will not progress the RCU through its grace period and a
synchronize_rcu my get stuck. Without this patch I have a box that will
not boot when PREEMPT_RCU and NO_HZ are set. That same box boots fine
with this patch.
This patch comes from the -rt kernel where it has been tested for
several months.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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