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2011-07-12KVM: PPC: e500: Add shadow PID supportLiu Yu
Dynamically assign host PIDs to guest PIDs, splitting each guest PID into multiple host (shadow) PIDs based on kernel/user and MSR[IS/DS]. Use both PID0 and PID1 so that the shadow PIDs for the right mode can be selected, that correspond both to guest TID = zero and guest TID = guest PID. This allows us to significantly reduce the frequency of needing to invalidate the entire TLB. When the guest mode or PID changes, we just update the host PID0/PID1. And since the allocation of shadow PIDs is global, multiple guests can share the TLB without conflict. Note that KVM does not yet support the guest setting PID1 or PID2 to a value other than zero. This will need to be fixed for nested KVM to work. Until then, we enforce the requirement for guest PID1/PID2 to stay zero by failing the emulation if the guest tries to set them to something else. Signed-off-by: Liu Yu <yu.liu@freescale.com> Signed-off-by: Scott Wood <scottwood@freescale.com> Signed-off-by: Alexander Graf <agraf@suse.de>
2011-07-12KVM: PPC: e500: Save/restore SPE stateScott Wood
This is done lazily. The SPE save will be done only if the guest has used SPE since the last preemption or heavyweight exit. Restore will be done only on demand, when enabling MSR_SPE in the shadow MSR, in response to an SPE fault or mtmsr emulation. For SPEFSCR, Linux already switches it on context switch (non-lazily), so the only remaining bit is to save it between qemu and the guest. Signed-off-by: Liu Yu <yu.liu@freescale.com> Signed-off-by: Scott Wood <scottwood@freescale.com> Signed-off-by: Alexander Graf <agraf@suse.de>
2011-07-12KVM: PPC: booke: use shadow_msrScott Wood
Keep the guest MSR and the guest-mode true MSR separate, rather than modifying the guest MSR on each guest entry to produce a true MSR. Any bits which should be modified based on guest MSR must be explicitly propagated from vcpu->arch.shared->msr to vcpu->arch.shadow_msr in kvmppc_set_msr(). While we're modifying the guest entry code, reorder a few instructions to bury some load latencies. Signed-off-by: Scott Wood <scottwood@freescale.com> Signed-off-by: Alexander Graf <agraf@suse.de>
2011-07-12powerpc/e500: SPE register saving: take arbitrary struct offsetScott Wood
Previously, these macros hardcoded THREAD_EVR0 as the base of the save area, relative to the base register passed. This base offset is now passed as a separate macro parameter, allowing reuse with other SPE save areas, such as used by KVM. Acked-by: Kumar Gala <galak@kernel.crashing.org> Signed-off-by: Scott Wood <scottwood@freescale.com> Signed-off-by: Alexander Graf <agraf@suse.de>
2011-07-12powerpc/e500: Save SPEFCSR in flush_spe_to_thread()yu liu
giveup_spe() saves the SPE state which is protected by MSR[SPE]. However, modifying SPEFSCR does not trap when MSR[SPE]=0. And since SPEFSCR is already saved/restored in _switch(), not all the callers want to save SPEFSCR again. Thus, saving SPEFSCR should not belong to giveup_spe(). This patch moves SPEFSCR saving to flush_spe_to_thread(), and cleans up the caller that needs to save SPEFSCR accordingly. Signed-off-by: Liu Yu <yu.liu@freescale.com> Acked-by: Kumar Gala <galak@kernel.crashing.org> Signed-off-by: Scott Wood <scottwood@freescale.com> Signed-off-by: Alexander Graf <agraf@suse.de>
2011-07-11Merge branch 'master' into for-nextJiri Kosina
Sync with Linus' tree to be able to apply pending patches that are based on newer code already present upstream.
2011-07-08powerpc: Dont require a dma_ops struct to set dma maskKumar Gala
The only reason to require a dma_ops struct is to see if it has implemented set_dma_mask. If not we can fall back to setting the mask directly. This resolves an issue with how to sequence the setting of a DMA mask for platform devices. Before we had an issue in that we have no way of setting the DMA mask before the various low level bus notifiers get called that might check it (swiotlb). So now we can do: pdev = platform_device_alloc("foobar", 0); dma_set_mask(&pdev->dev, DMA_BIT_MASK(37)); platform_device_add(pdev); And expect the right thing to happen with the bus notifiers get called via platform_device_add. Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2011-07-08powerpc: implement arch_setup_pdev_archdataKumar Gala
We have a long standing issues with platform devices not have a valid dma_mask pointer. This hasn't been an issue to date as no platform device has tried to set its dma_mask value to a non-default value. Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2011-07-08powerpc: Create next_tlbcam_idx percpu variable for FSL_BOOKEBecky Bruce
This is used to round-robin TLBCAM entries. Signed-off-by: Becky Bruce <beckyb@kernel.crashing.org> Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2011-07-01perf: Add context field to perf_eventAvi Kivity
The perf_event overflow handler does not receive any caller-derived argument, so many callers need to resort to looking up the perf_event in their local data structure. This is ugly and doesn't scale if a single callback services many perf_events. Fix by adding a context parameter to perf_event_create_kernel_counter() (and derived hardware breakpoints APIs) and storing it in the perf_event. The field can be accessed from the callback as event->overflow_handler_context. All callers are updated. Signed-off-by: Avi Kivity <avi@redhat.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1309362157-6596-2-git-send-email-avi@redhat.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-07-01perf, arch: Add generic NODE cache eventsPeter Zijlstra
Add a NODE level to the generic cache events which is used to measure local vs remote memory accesses. Like all other cache events, an ACCESS is HIT+MISS, if there is no way to distinguish between reads and writes do reads only etc.. The below needs filling out for !x86 (which I filled out with unsupported events). I'm fairly sure ARM can leave it like that since it doesn't strike me as an architecture that even has NUMA support. SH might have something since it does appear to have some NUMA bits. Sparc64, PowerPC and MIPS certainly want a good look there since they clearly are NUMA capable. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: David Miller <davem@davemloft.net> Cc: Anton Blanchard <anton@samba.org> Cc: David Daney <ddaney@caviumnetworks.com> Cc: Deng-Cheng Zhu <dengcheng.zhu@gmail.com> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Will Deacon <will.deacon@arm.com> Cc: Robert Richter <robert.richter@amd.com> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/r/1303508226.4865.8.camel@laptop Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-07-01perf: Remove the nmi parameter from the swevent and overflow interfacePeter Zijlstra
The nmi parameter indicated if we could do wakeups from the current context, if not, we would set some state and self-IPI and let the resulting interrupt do the wakeup. For the various event classes: - hardware: nmi=0; PMI is in fact an NMI or we run irq_work_run from the PMI-tail (ARM etc.) - tracepoint: nmi=0; since tracepoint could be from NMI context. - software: nmi=[0,1]; some, like the schedule thing cannot perform wakeups, and hence need 0. As one can see, there is very little nmi=1 usage, and the down-side of not using it is that on some platforms some software events can have a jiffy delay in wakeup (when arch_irq_work_raise isn't implemented). The up-side however is that we can remove the nmi parameter and save a bunch of conditionals in fast paths. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Michael Cree <mcree@orcon.net.nz> Cc: Will Deacon <will.deacon@arm.com> Cc: Deng-Cheng Zhu <dengcheng.zhu@gmail.com> Cc: Anton Blanchard <anton@samba.org> Cc: Eric B Munson <emunson@mgebm.net> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Paul Mundt <lethal@linux-sh.org> Cc: David S. Miller <davem@davemloft.net> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jason Wessel <jason.wessel@windriver.com> Cc: Don Zickus <dzickus@redhat.com> Link: http://lkml.kernel.org/n/tip-agjev8eu666tvknpb3iaj0fg@git.kernel.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-07-01irq_work, ppc: Fix up arch hooksPeter Zijlstra
Commit e360adbe29 ("irq_work: Add generic hardirq context callbacks") fouled up the ppc bit, not properly naming the arch specific function that raises the 'self-IPI'. Cc: Huang Ying <ying.huang@intel.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Anton Blanchard <anton@samba.org> Cc: Eric B Munson <emunson@mgebm.net> Cc: stable@kernel.org # 37+ Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/n/tip-eg0aqien8p1aqvzu9dft6dtv@git.kernel.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-07-01powerpc: Add jump label supportMichael Ellerman
This patch adds support for the new "jump label" feature. Unlike x86 and sparc we just merrily patch the code with no locks etc, as far as I know this is safe, but I'm not really sure what the x86/sparc code is protecting against so maybe it's not. I also don't see any reason for us to implement the poke_early() routine, even though sparc does. [BenH: Updated the patch to upstream generic changes] Signed-off-by: Michael Ellerman <michael@ellerman.id.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-06-30powerpc: Add printk companion for ppc_md.progressDave Carroll
This patch adds a printk companion to replace the udbg progress function when initmem is freed. Suggested-by: Milton Miller <miltonm@bga.com> Suggested-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Dave Carroll <dcarroll@astekcorp.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-06-30Merge remote branch 'origin/master' into nextBenjamin Herrenschmidt
2011-06-29powerpc/pseries: Re-implement HVSI as part of hvc_vioBenjamin Herrenschmidt
On pseries machines, consoles are provided by the hypervisor using a low level get_chars/put_chars type interface. However, this is really just a transport to the service processor which implements them either as "raw" console (networked consoles, HMC, ...) or as "hvsi" serial ports. The later is a simple packet protocol on top of the raw character interface that is supposed to convey additional "serial port" style semantics. In practice however, all it does is provide a way to read the CD line and set/clear our DTR line, that's it. We currently implement the "raw" protocol as an hvc console backend (/dev/hvcN) and the "hvsi" protocol using a separate tty driver (/dev/hvsi0). However this is quite impractical. The arbitrary difference between the two type of devices has been a major source of user (and distro) confusion. Additionally, there's an additional mini -hvsi implementation in the pseries platform code for our low level debug console and early boot kernel messages, which means code duplication, though that low level variant is impractical as it's incapable of doing the initial protocol negociation to establish the link to the FSP. This essentially replaces the dedicated hvsi driver and the platform udbg code completely by extending the existing hvc_vio backend used in "raw" mode so that: - It now supports HVSI as well - We add support for hvc backend providing tiocm{get,set} - It also provides a udbg interface for early debug and boot console This is overall less code, though this will only be obvious once we remove the old "hvsi" driver, which is still available for now. When the old driver is enabled, the new code still kicks in for the low level udbg console, replacing the old mini implementation in the platform code, it just doesn't provide the higher level "hvc" interface. In addition to producing generally simler code, this has several benefits over our current situation: - The user/distro only has to deal with /dev/hvcN for the hypervisor console, avoiding all sort of confusion that has plagued us in the past - The tty, kernel and low level debug console all use the same code base which supports the full protocol establishment process, thus the console is now available much earlier than it used to be with the old HVSI driver. The kernel console works much earlier and udbg is available much earlier too. Hackers can enable a hard coded very-early debug console as well that works with HVSI (previously that was only supported for the "raw" mode). I've tried to keep the same semantics as hvsi relative to how I react to things like CD changes, with some subtle differences though: - I clear DTR on close if HUPCL is set - Current hvsi triggers a hangup if it detects a up->down transition on CD (you can still open a console with CD down). My new implementation triggers a hangup if the link to the FSP is severed, and severs it upon detecting a up->down transition on CD. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-06-29powerpc/udbg: Register udbg console genericallyBenjamin Herrenschmidt
When CONFIG_PPC_EARLY_DEBUG is set, call register_early_udbg_console() early from generic code. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-06-29powerpc/pseries: Improve error code on reconfiguration notifier failureAkinobu Mita
Reconfiguration notifier call for device node may fail by several reasons, but it always assumes kmalloc failures. This enables reconfiguration notifier call chain to get the actual error code rather than -ENOMEM by converting all reconfiguration notifier calls to return encapsulate error code with notifier_from_errno(). Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: linuxppc-dev@lists.ozlabs.org Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-06-29powerpc/maple: Enable scom access functions on MapleDmitry Eremin-Solenikov
Enable functions used to access SCOM if PPC_MAPLE is defined: they are used by cpufreq driver to control hardware. Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-06-29powerpc/book3e-64: Reraise doorbell when masked by soft-irq-disableScott Wood
Signed-off-by: Scott Wood <scottwood@freescale.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-06-29arch/powerpc: use printk_ratelimited instead of printk_ratelimitChristian Dietrich
Since printk_ratelimit() shouldn't be used anymore (see comment in include/linux/printk.h), replace it with printk_ratelimited. Signed-off-by: Christian Dietrich <christian.dietrich@informatik.uni-erlangen.de> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-06-29powerpc/rtas-rtc: remove sideeffects of printk_ratelimitChristian Dietrich
Don't use printk_ratelimit() as an additional condition for returning on an error. Because when the ratelimit is reached, printk_ratelimit will return 0 and e.g. in rtas_get_boot_time won't check for an error condition. Signed-off-by: Christian Dietrich <christian.dietrich@informatik.uni-erlangen.de> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-06-27powerpc/e500mc: Add support for the wait instruction in e500_idleScott Wood
e500mc cannot doze or nap due to an erratum (as well as having a different mechanism than previous e500), but it has a "wait" instruction that is similar to doze. On 64-bit, due to the soft-irq-disable mechanism, the existing book3e_idle should be used instead. Signed-off-by: Vakul Garg <vakul@freescale.com> Signed-off-by: Scott Wood <scottwood@freescale.com> Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2011-06-22powerpc: make irq_choose_cpu() available to all PIC driversStuart Yoder
Move irq_choose_cpu() into arch/powerpc/kernel/irq.c so that it can be used by other PIC drivers. The function is not MPIC-specific. Signed-off-by: Stuart Yoder <stuart.yoder@freescale.com> Signed-off-by: Timur Tabi <timur@freescale.com> Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2011-06-22powerpc/pci: Move FSL fixup from 32-bit to commonKumar Gala
We need the FSL specific header fixup code on both 32-bit and 64-bit platforms so just move the code into pci-common.c. Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2011-06-22powerpc/85xx: Save scratch registers to thread info instead of using SPRGs.Ashish Kalra
We expect this is actually faster, and we end up needing more space than we can get from the SPRGs in some instances. This is also useful when running as a guest OS - SPRGs4-7 do not have guest versions. 8 slots are allocated in thread_info for this even though we only actually use 4 of them - this allows space for future code to have more scratch space (and we know we'll need it for things like hugetlb). Signed-off-by: Ashish Kalra <Ashish.Kalra@freescale.com> Signed-off-by: Becky Bruce <beckyb@kernel.crashing.org> Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2011-06-22powerpc/e500: fix breakage with fsl_rio_mcheck_exceptionScott Wood
The wrong MCSR bit was being used on e500mc. MCSR_BUS_RBERR only exists on e500v1/v2. Use MCSR_LD on e500mc, and remove all MCSR checking in fsl_rio_mcheck_exception as we now no longer call that function if the appropriate bit in MCSR is not set. If RIO support was enabled at compile-time, but was never probed, just return from fsl_rio_mcheck_exception rather than dereference a NULL pointer. TODO: There is still a remaining, though comparitively minor, issue in that this recovery mechanism will falsely engage if there's an unrelated MCSR_LD event at the same time as a RIO error. Signed-off-by: Scott Wood <scottwood@freescale.com> Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2011-06-20powerpc: Avoid extra indirect function call in sending IPIsPaul Mackerras
On many platforms (including pSeries), smp_ops->message_pass is always smp_muxed_ipi_message_pass. This changes arch/powerpc/kernel/smp.c so that if smp_ops->message_pass is NULL, it calls smp_muxed_ipi_message_pass directly. This means that a platform doesn't need to set both .message_pass and .cause_ipi, only one of them. It is a slight performance improvement in that it gets rid of an indirect function call at the expense of a predictable conditional branch. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-06-17powerpc: Fix early boot accounting of CPUsMatt Evans
smp_release_cpus() waits for all cpus (including the bootcpu) due to an off-by-one count on boot_cpu_count (which is all CPUs). This patch replaces that with spinning_secondaries (which is all secondary CPUs). Signed-off-by: Matt Evans <matt@ozlabs.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-06-10treewide: Convert uses of struct resource to resource_size(ptr)Joe Perches
Several fixes as well where the +1 was missing. Done via coccinelle scripts like: @@ struct resource *ptr; @@ - ptr->end - ptr->start + 1 + resource_size(ptr) and some grep and typing. Mostly uncompiled, no cross-compilers. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-06-09powerpc: Force page alignment for initrd reserved memoryBenjamin Herrenschmidt
When using 64K pages with a separate cpio rootfs, U-Boot will align the rootfs on a 4K page boundary. When the memory is reserved, and subsequent early memblock_alloc is called, it will allocate memory between the 64K page alignment and reserved memory. When the reserved memory is subsequently freed, it is done so by pages, causing the early memblock_alloc requests to be re-used, which in my case, caused the device-tree to be clobbered. This patch forces the reserved memory for initrd to be kernel page aligned, and will move the device tree if it overlaps with the range extension of initrd. This patch will also consolidate the identical function free_initrd_mem() from mm/init_32.c, init_64.c to mm/mem.c, and adds the same range extension when freeing initrd. free_initrd_mem() is also moved to the __init section. Many thanks to Milton Miller for his input on this patch. [BenH: Fixed build without CONFIG_BLK_DEV_INITRD] Signed-off-by: Dave Carroll <dcarroll@astekcorp.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-06-09Merge remote branch 'kumar/merge' into mergeBenjamin Herrenschmidt
2011-06-08pci/of: Match PCI devices to OF nodes dynamicallyBenjamin Herrenschmidt
powerpc has two different ways of matching PCI devices to their corresponding OF node (if any) for historical reasons. The ppc64 one does a scan looking for matching bus/dev/fn, while the ppc32 one does a scan looking only for matching dev/fn on each level in order to be agnostic to busses being renumbered (which Linux does on some platforms). This removes both and instead moves the matching code to the PCI core itself. It's the most logical place to do it: when a pci_dev is created, we know the parent and thus can do a single level scan for the matching device_node (if any). The benefit is that all archs now get the matching for free. There's one hook the arch might want to provide to match a PHB bus to its device node. A default weak implementation is provided that looks for the parent device device node, but it's not entirely reliable on powerpc for various reasons so powerpc provides its own. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Acked-by: Michal Simek <monstr@monstr.eu> Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2011-06-02powerpc/book3e: Fix CPU feature handling on e5500 in 32-bit modeKumar Gala
We are missing FPU feature bit that user space may require. In the 64-bit mode this gets set since we pull it in via COMMON_USER_PPC64. We just explicitly set it so user space will be happy again. Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2011-05-27Merge branch 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-armLinus Torvalds
* 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm: (45 commits) ARM: 6945/1: Add unwinding support for division functions ARM: kill pmd_off() ARM: 6944/1: mm: allow ASID 0 to be allocated to tasks ARM: 6943/1: mm: use TTBR1 instead of reserved context ID ARM: 6942/1: mm: make TTBR1 always point to swapper_pg_dir on ARMv6/7 ARM: 6941/1: cache: ensure MVA is cacheline aligned in flush_kern_dcache_area ARM: add sendmmsg syscall ARM: 6863/1: allow hotplug on msm ARM: 6832/1: mmci: support for ST-Ericsson db8500v2 ARM: 6830/1: mach-ux500: force PrimeCell revisions ARM: 6829/1: amba: make hardcoded periphid override hardware ARM: 6828/1: mach-ux500: delete SSP PrimeCell ID ARM: 6827/1: mach-netx: delete hardcoded periphid ARM: 6940/1: fiq: Briefly document driver responsibilities for suspend/resume ARM: 6938/1: fiq: Refactor {get,set}_fiq_regs() for Thumb-2 ARM: 6914/1: sparsemem: fix highmem detection when using SPARSEMEM ARM: 6913/1: sparsemem: allow pfn_valid to be overridden when using SPARSEMEM at91: drop at572d940hf support at91rm9200: introduce at91rm9200_set_type to specficy cpu package at91: drop boot_params and PLAT_PHYS_OFFSET ...
2011-05-27Merge branches 'devel', 'devel-stable' and 'fixes' into for-linusRussell King
2011-05-27Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/suspend-2.6 * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/suspend-2.6: PM: Fix PM QOS's user mode interface to work with ASCII input PM / Hibernate: Update kerneldoc comments in hibernate.c PM / Hibernate: Remove arch_prepare_suspend() PM / Hibernate: Update some comments in core hibernate code
2011-05-27Merge remote branch 'kumar/merge' into mergeBenjamin Herrenschmidt
2011-05-26powerpc: Fix irq_free_virt by adjusting bounds before loopMilton Miller
Instead of looping over each irq and checking against the irq array bounds, adjust the bounds before looping. The old code will not free any irq if the irq + count is above irq_virq_count because the test in the loop is testing irq + count instead of irq + i. This code checks the limits to avoid unsigned integer overflows. Signed-off-by: Milton Miller <miltonm@bga.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-05-26powerpc/irq: Protect irq_radix_revmap_lookup against irq_free_virtMilton Miller
The radix-tree code uses call_rcu when freeing internal elements. We must protect against the elements being freed while we traverse the tree, even if the returned pointer will still be valid. While preparing a patch to expand the context in which irq_radix_revmap_lookup will be called, I realized that the radix tree was not locked. When asked For a normal call_rcu usage, is it allowed to read the structure in irq_enter / irq_exit, without additional rcu_read_lock? Could an element freed with call_rcu advance with the cpu still between irq_enter/irq_exit (and irq_disabled())? Paul McKenney replied: Absolutely illegal to do so. OK for call_rcu_sched(), but a flaming bug for call_rcu(). And thank you very much for finding this!!! Further analysis: In the current CONFIG_TREE_RCU implementation. CONFIG_TREE_PREEMPT_RCU (and CONFIG_TINY_PREEMPT_RCU) uses explicit counters. These counters are reflected from per-CPU to global in the scheduling-clock-interrupt handler, so disabling irq does prevent the grace period from completing. But there are real-time implementations (such as the one use by the Concurrent guys) where disabling irq does -not- prevent the grace period from completing. While an alternative fix would be to switch radix-tree to rcu_sched, I don't want to audit the other users of radix trees (nor put alternative freeing in the library). The normal overhead for rcu_read_lock and unlock are a local counter increment and decrement. This does not show up in the rcu lockdep because in 2.6.34 commit 2676a58c98 (radix-tree: Disable RCU lockdep checking in radix tree) deemed it too hard to pass the condition of the protecting lock to the library. Signed-off-by: Milton Miller <miltonm@bga.com> Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-05-26powerpc/irq: Check desc in handle_one_irq and expand generic_handle_irqMilton Miller
Look up the descriptor and check that it is found in handle_one_irq before checking if we are on the irq stack, and call the handler directly using the descriptor if we are on the stack. We need check irq_to_desc finds the descriptor to avoid a NULL pointer dereference. It could have failed because the number from ppc_md.get_irq was above NR_IRQS, or various exceptional conditions with sparse irqs (eg race conditions while freeing an irq if its was not shutdown in the controller). fe12bc2c99 (genirq: Uninline and sanity check generic_handle_irq()) moved generic_handle_irq out of line to allow its use by interrupt controllers in modules. However, handle_one_irq is core arch code. It already knows the details of struct irq_desc and handling irqs in the nested irq case. This will avoid the extra stack frame to return the value we don't check. Signed-off-by: Milton Miller <miltonm@bga.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-05-26powerpc/irq: Always free duplicate IRQ_LEGACY hostsMilton Miller
Since kmem caches are allocated before init_IRQ as noted in 3af259d155 (powerpc: Radix trees are available before init_IRQ), we now call kmalloc in all cases and can can always call kfree if we are asked to allocate a duplicate or conflicting IRQ_HOST_MAP_LEGACY host. Signed-off-by: Milton Miller <miltonm@bga.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-05-26powerpc/irq: Remove stale and misleading commentMilton Miller
The comment claims we will call host->ops->map() to update the flags if we find a previously established mapping, but we never did. We used to call remap, but that call was removed in da05198002 (powerpc: Remove irq_host_ops->remap hook). Signed-off-by: Milton Miller <miltonm@bga.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-05-26powerpc/cell: Use common smp ipi actionsMilton Miller
The cell iic interrupt controller has enough software caused interrupts to use a unique interrupt for each of the 4 messages powerpc uses. This means each interrupt gets its own irq action/data combination. Use the seperate, optimized, arch common ipi action functions registered via the helper smp_request_message_ipi instead passing the message as action data to a single action that then demultipexes to the required acton via a switch statement. smp_request_message_ipi will register the action as IRQF_PER_CPU and IRQF_DISABLED, and WARN if the allocation fails for some reason, so no need to print on that failure. It will return positive if the message will not be used by the kernel, in which case we can free the virq. In addition to elimiating inefficient code, this also corrects the error that a kernel built with kexec but without a debugger would not register the ipi for kdump to notify the other cpus of a crash. This also restores the debugger action to be static to kernel/smp.c. Signed-off-by: Milton Miller <miltonm@bga.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-05-26powerpc/ftrace: Implement raw syscall tracepoints on PowerPCIan Munsie
This patch implements the raw syscall tracepoints on PowerPC and exports them for ftrace syscalls to use. To minimise reworking existing code, I slightly re-ordered the thread info flags such that the new TIF_SYSCALL_TRACEPOINT bit would still fit within the 16 bits of the andi. instruction's UI field. The instructions in question are in /arch/powerpc/kernel/entry_{32,64}.S to and the _TIF_SYSCALL_T_OR_A with the thread flags to see if system call tracing is enabled. In the case of 64bit PowerPC, arch_syscall_addr and arch_syscall_match_sym_name are overridden to allow ftrace syscalls to work given the unusual system call table structure and symbol names that start with a period. Signed-off-by: Ian Munsie <imunsie@au1.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-05-26Merge branch 'for-rmk' of git://github.com/at91linux/linux-2.6-at91 into ↵Russell King
devel-stable
2011-05-25powerpc: mmu_gather reworkPeter Zijlstra
Fix up powerpc to the new mmu_gather stuff. PPC has an extra batching queue to RCU free the actual pagetable allocations, use the ARCH extentions for that for now. For the ppc64_tlb_batch, which tracks the vaddrs to unhash from the hardware hash-table, keep using per-cpu arrays but flush on context switch and use a TLF bit to track the lazy_mmu state. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: David Miller <davem@davemloft.net> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Jeff Dike <jdike@addtoit.com> Cc: Richard Weinberger <richard@nod.at> Cc: Tony Luck <tony.luck@intel.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Hugh Dickins <hughd@google.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Nick Piggin <npiggin@kernel.dk> Cc: Namhyung Kim <namhyung@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-05-25Merge branch 'devicetree/arm-next' of git://git.secretlab.ca/git/linux-2.6 ↵Russell King
into devel-stable
2011-05-24PM / Hibernate: Remove arch_prepare_suspend()Rafael J. Wysocki
All architectures supporting hibernation define arch_prepare_suspend() as an empty function, so remove it. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>