- 16 Mar, 2008 21 commits
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Mike Isely authored
The i915_vblank_swap() function schedules an automatic buffer swap upon receipt of the vertical sync interrupt. Such an operation is lengthy so it can't be allowed to happen in normal interrupt context, thus the DRM implements this by scheduling the work in a kernel softirq-scheduled tasklet. In order for the buffer swap to work safely, the DRM's central lock must be taken, via a call to drm_lock_take() located in drivers/char/drm/drm_irq.c within the function drm_locked_tasklet_func(). The lock-taking logic uses a non-interrupt-blocking spinlock to implement the manipulations needed to take the lock. This semantic would be safe if all attempts to use the spinlock only happen from process context. However this buffer swap happens from softirq context which is really a form of interrupt context. Thus we have an unsafe situation, in that drm_locked_tasklet_func() can block on a spinlock already taken by a thread in process context which will never get scheduled again because of the blocked softirq tasklet. This wedges the kernel hard. To trigger this bug, run a dual-head cloned mode configuration which uses the i915 drm, then execute an opengl application which synchronizes buffer swaps against the vertical sync interrupt. In my testing, a lockup always results after running anywhere from 5 minutes to an hour and a half. I believe dual-head is needed to really trigger the problem because then the vertical sync interrupt handling is no longer predictable (due to being interrupt-sourced from two different heads running at different speeds). This raises the probability of the tasklet trying to run while the userspace DRI is doing things to the GPU (and manipulating the DRM lock). The fix is to change the relevant spinlock semantics to be the interrupt-blocking form. After this change I am no longer able to trigger the lockup; the longest test run so far was 20 hours (test stopped after that point). Note: I have examined the places where this spinlock is being employed; all are reasonably short bounded sequences and should be suitable for interrupts being blocked without impacting overall kernel interrupt response latency. Signed-off-by: Mike Isely <isely@pobox.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
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Linus Torvalds authored
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git://git.kernel.org/pub/scm/linux/kernel/git/kyle/parisc-2.6Linus Torvalds authored
* 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/kyle/parisc-2.6: [PARISC] make ptr_to_pide() static [PARISC] head.S: section mismatch fixes [PARISC] add back Crestone Peak cpu [PARISC] futex: special case cmpxchg NULL in kernel space [PARISC] clean up show_stack [PARISC] add pa8900 CPUs to hardware inventory [PARISC] clean up include/asm-parisc/elf.h [PARISC] move defconfig to arch/parisc/configs/ [PARISC] add back AD1889 MAINTAINERS entry [PARISC] pdc_console: fix bizarre panic on boot [PARISC] dump_stack in show_regs [PARISC] pdc_stable: fix compile errors [PARISC] remove unused pdc_iodc_printf function [PARISC] bump __NR_syscalls [PARISC] unbreak pgalloc.h [PARISC] move VMALLOC_* definitions to fixmap.h [PARISC] wire up timerfd syscalls [PARISC] remove old timerfd syscall
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FUJITA Tomonori authored
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
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Helge Deller authored
- move boot_args[] into the init section - move $global$ into the read_mostly section - fix the following two section mismatches: WARNING: vmlinux.o(.text+0x9c): Section mismatch: reference to .init.text:start_kernel (between '$pgt_fill_loop' and '$is_pa20') WARNING: vmlinux.o(.text+0xa0): Section mismatch: reference to .init.text:start_kernel (between '$pgt_fill_loop' and '$is_pa20') Signed-off-by: Helge Deller <deller@gmx.de> SIgned-off-by: Kyle McMartin <kyle@mcmartin.ca>
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Kyle McMartin authored
Crestone Peak Slow is the 800MHz PA-8800 cpu in the C8000. 0x88B is probably the Crestone Peak Fast. Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
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Kyle McMartin authored
Commit a0c1e907 added code to futex.c to detect whether futex_atomic_cmpxchg_inatomic was implemented at run time: + curval = cmpxchg_futex_value_locked(NULL, 0, 0); + if (curval == -EFAULT) + futex_cmpxchg_enabled = 1; This is bogus on parisc, since page zero in kernel virtual space is the gateway page for syscall entry, and should not be read from the kernel. (That, and we really don't like the kernel faulting on its own address space...) Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
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Kyle McMartin authored
When we show_regs, we obviously have a struct pt_regs of the calling frame. Use these in show_stack so we don't have the entire bogus call trace up to the show_stack call. Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
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James Bottomley authored
This patch adds the known pa8900 CPUs to the inventory list and removes the Crestone Peak one which apparently never escaped into the wild. Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com> Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
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Randolph Chung authored
Cleanup some cruft. No functionality changes. Signed-off-by: Randolph Chung <tausq@parisc-linux.org> Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
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Adrian Bunk authored
This patch moves the default parisc defconfig to arch/parisc/configs/generic_defconfig where it belongs and selects it as the default defconfig through KBUILD_DEFCONFIG. Signed-off-by: Adrian Bunk <adrian.bunk@movial.fi> Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
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Thibaut VARENE authored
Signed-off-by: Thibaut VARENE <T-Bone@parisc-linux.org> Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
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Kyle McMartin authored
Commit 721fdf34 introduced a subtle bug by accidently removing the "static" from iodc_dbuf. This resulted in, what appeared to be, a trap without *current set to a task. Probably the result of a trap in real mode while calling firmware. Also do other misc clean ups. Since the only input from firmware is non blocking, share iodc_dbuf between input and output, and spinlock the only callers. Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
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Kyle McMartin authored
Originally, show_stack was used in BUG() output. However, a recent commit changed it to print register state (no idea what that's supposed to help, really...) and parisc was missing a backtrace because of it. Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
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Joel Soete authored
Signed-off-by: Joel Soete <rubisher@scarlet.be> Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
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Kyle McMartin authored
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
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Kyle McMartin authored
oops, forgot this in the previous commit. Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
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Kyle McMartin authored
Commit 2f569afd broke the compile rather spectacularly. Fix code errors. Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
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Kyle McMartin authored
They make way more sense here, really... Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
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Kyle McMartin authored
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
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Kyle McMartin authored
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
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- 15 Mar, 2008 10 commits
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Linus Torvalds authored
This essentially reverts commit 71fc47a9 ("ACPI: basic initramfs DSDT override support"), because the code simply isn't ready. It did ugly things to the init sequence to populate the rootfs image early, but that just ended up showing other problems with the whole approach. The fact is, the VFS layer simply isn't initialized this early, and the relevant ACPI code should either run much later, or this shouldn't be done at all. For 2.6.25, we'll just pick the latter option. We can revisit this concept later if necessary. Cc: Dave Hansen <haveblue@us.ibm.com> Cc: Tilman Schmidt <tilman@imap.cc> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Thomas Renninger <trenn@suse.de> Cc: Eric Piel <eric.piel@tremplin-utc.net> Cc: Len Brown <len.brown@intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Markus Gaugusch <dsdt@gaugusch.at> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Roel Kluin authored
DATA_CARRY is not boolean Signed-off-by: Roel Kluin <12o3l@tiscali.nl> Signed-off-by: Pierre Ossman <drzeus@drzeus.cx> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6Linus Torvalds authored
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: [NET]: Fix tbench regression in 2.6.25-rc1
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Ingo Molnar authored
Use the existing calc_delta_mine() calculation for sched_slice(). This saves a divide and simplifies the code because we share it with the other /cfs_rq->load users. It also improves code size: text data bss dec hex filename 42659 2740 144 45543 b1e7 sched.o.before 42093 2740 144 44977 afb1 sched.o.after Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
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Ingo Molnar authored
Fair sleepers need to scale their latency target down by runqueue weight. Otherwise busy systems will gain ever larger sleep bonus. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
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Peter Zijlstra authored
Currently we schedule to the leftmost task in the runqueue. When the runtimes are very short because of some server/client ping-pong, especially in over-saturated workloads, this will cycle through all tasks trashing the cache. Reduce cache trashing by keeping dependent tasks together by running newly woken tasks first. However, by not running the leftmost task first we could starve tasks because the wakee can gain unlimited runtime. Therefore we only run the wakee if its within a small (wakeup_granularity) window of the leftmost task. This preserves fairness, but does alternate server/client task groups. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
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Ingo Molnar authored
lw->weight can be 0 for a short time during bootup. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
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Ingo Molnar authored
Clear the cached inverse value when updating load. This is needed for calc_delta_mine() to work correctly when using the rq load. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
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Peter Zijlstra authored
Current min_vruntime tracking is incorrect and will cause serious problems when we don't run the leftmost task for some reason. min_vruntime does two things; 1) it's used to determine a forward direction when the u64 vruntime wraps, 2) it's used to track the leftmost vruntime to position newly enqueued tasks from. The current logic advances min_vruntime whenever the current task's vruntime advance. Because the current task may pass the leftmost task still waiting we're failing the second goal. This causes new tasks to be placed too far ahead and thus penalizes their runtime. Fix this by making min_vruntime the min_vruntime of the waiting tasks by tracking it in enqueue/dequeue, and compare against current's vruntime to obtain the absolute minimum when placing new tasks. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
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Hiroshi Shimamoto authored
Fix a hard to trigger crash seen in the -rt kernel that also affects the vanilla scheduler. There is a race condition between schedule() and some dequeue/enqueue functions; rt_mutex_setprio(), __setscheduler() and sched_move_task(). When scheduling to idle, idle_balance() is called to pull tasks from other busy processor. It might drop the rq lock. It means that those 3 functions encounter on_rq=0 and running=1. The current task should be put when running. Here is a possible scenario: CPU0 CPU1 | schedule() | ->deactivate_task() | ->idle_balance() | -->load_balance_newidle() rt_mutex_setprio() | | --->double_lock_balance() *get lock *rel lock * on_rq=0, ruuning=1 | * sched_class is changed | *rel lock *get lock : | : ->put_prev_task_rt() ->pick_next_task_fair() => panic The current process of CPU1(P1) is scheduling. Deactivated P1, and the scheduler looks for another process on other CPU's runqueue because CPU1 will be idle. idle_balance(), load_balance_newidle() and double_lock_balance() are called and double_lock_balance() could drop the rq lock. On the other hand, CPU0 is trying to boost the priority of P1. The result of boosting only P1's prio and sched_class are changed to RT. The sched entities of P1 and P1's group are never put. It makes cfs_rq invalid, because the cfs_rq has curr and no leaf, but pick_next_task_fair() is called, then the kernel panics. Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
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- 14 Mar, 2008 3 commits
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git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6Linus Torvalds authored
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6: firewire: fw-ohci: shut up false compiler warning on PPC32 firewire: fw-ohci: use dma_alloc_coherent for ar_buffer ieee1394: sbp2: fix for SYM13FW500 bridge (Datafab disk) firewire: fw-sbp2: fix for SYM13FW500 bridge (Datafab disk) firewire: update Kconfig help text firewire: warn on fatal condition in topology code firewire: fw-sbp2: set single-phase retry_limit firewire: fw-ohci: Apple UniNorth 1st generation support firewire: fw-ohci: PPC PMac platform code firewire: endianess annotations firewire: endianess fix
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J. Bruce Fields authored
This bug was always here, but before my commit 6fa02839 ("recheck for secure ports in fh_verify"), it could only be triggered by failure of a kmalloc(). After that commit it could be triggered by a client making a request from a non-reserved port for access to an export marked "secure". (Exports are "secure" by default.) The result is a struct svc_export with a reference count one too low, resulting in likely oopses next time the export is accessed. The reference counting here is not straightforward; a later patch will clean up fh_verify(). Thanks to Lukas Hejtmanek for the bug report and followup. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu> Cc: Lukas Hejtmanek <xhejtman@ics.muni.cz> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Marc Dionne authored
The comments in the definition of struct export_operations don't match the current members. Add a comment for the 2 new functions and remove 2 comments for unused ones. Signed-off-by: Marc Dionne <marc.c.dionne@gmail.com> Acked-by: David Howells <dhowells@redhat.com> Acked-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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- 13 Mar, 2008 6 commits
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Stefan Richter authored
Shut up "may be used uninitialised in this function" warnings due to PPC32's implementation of dma_alloc_coherent(). Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
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Jarod Wilson authored
Currently, we do nothing to guarantee we have a consistent DMA buffer for asynchronous receive packets. Rather than doing several sync's following a dma_map_single() to get consistent buffers, just switch to using dma_alloc_coherent(). Resolves constant buffer failures on my own x86_64 laptop w/4GB of RAM and likely to fix a number of other failures witnessed on x86_64 systems with 4GB of RAM or more. Signed-off-by: Jarod Wilson <jwilson@redhat.com> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
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Stefan Richter authored
Fix I/O errors due to SYM13FW500's inability to handle larger request sizes. Reported by Piergiorgio Sartor <piergiorgio.sartor@nexgo.de> for firewire-sbp2 in https://bugzilla.redhat.com/show_bug.cgi?id=436879 This fix is necessary because sbp2's default request size limit has been lifted since 2.6.25-rc1. Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> Signed-off-by: Jarod Wilson <jwilson@redhat.com>
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Stefan Richter authored
Fix I/O errors due to SYM13FW500's inability to handle larger request sizes. Reported by Piergiorgio Sartor <piergiorgio.sartor@nexgo.de> in https://bugzilla.redhat.com/show_bug.cgi?id=436879Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> Signed-off-by: Jarod Wilson <jwilson@redhat.com>
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Stefan Richter authored
Remove some less necessary information, point out that video1394 and dv1394 should be blacklisted along with ohci1394. Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
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Stefan Richter authored
If this ever happens to anybody, we want to have it in his log. Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
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