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2012-02-20i387: export 'fpu_owner_task' per-cpu variableLinus Torvalds
(And define it properly for x86-32, which had its 'current_task' declaration in separate from x86-64) Bitten by my dislike for modules on the machines I use, and the fact that apparently nobody else actually wanted to test the patches I sent out. Snif. Nobody else cares. Anyway, we probably should uninline the 'kernel_fpu_begin()' function that is what modules actually use and that references this, but this is the minimal fix for now. Reported-by: Josh Boyer <jwboyer@gmail.com> Reported-and-tested-by: Jongman Heo <jongman.heo@samsung.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-02-20x86: Specify a size for the cmp in the NMI handlerSteven Rostedt
Linus noticed that the cmp used to check if the code segment is __KERNEL_CS or not did not specify a size. Perhaps it does not matter as H. Peter Anvin noted that user space can not set the bottom two bits of the %cs register. But it's best not to let the assembly choose and change things between different versions of gas, but instead just pick the size. Four bytes are used to compare the saved code segment against __KERNEL_CS. Perhaps this might mess up Xen, but we can fix that when the time comes. Also I noticed that there was another non-specified cmp that checks the special stack variable if it is 1 or 0. This too probably doesn't matter what cmp is used, but this patch uses cmpl just to make it non ambiguous. Link: http://lkml.kernel.org/r/CA+55aFxfAn9MWRgS3O5k2tqN5ys1XrhSFVO5_9ZAoZKDVgNfGA@mail.gmail.com Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-02-20Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: [S390] correct ktime to tod clock comparator conversion [S390] 3215 deadlock with tty_wakeup [S390] incorrect PageTables counter for kvm page tables [S390] idle: avoid RCU usage in extended quiescent state
2012-02-20i387: support lazy restore of FPU stateLinus Torvalds
This makes us recognize when we try to restore FPU state that matches what we already have in the FPU on this CPU, and avoids the restore entirely if so. To do this, we add two new data fields: - a percpu 'fpu_owner_task' variable that gets written any time we update the "has_fpu" field, and thus acts as a kind of back-pointer to the task that owns the CPU. The exception is when we save the FPU state as part of a context switch - if the save can keep the FPU state around, we leave the 'fpu_owner_task' variable pointing at the task whose FP state still remains on the CPU. - a per-thread 'last_cpu' field, that indicates which CPU that thread used its FPU on last. We update this on every context switch (writing an invalid CPU number if the last context switch didn't leave the FPU in a lazily usable state), so we know that *that* thread has done nothing else with the FPU since. These two fields together can be used when next switching back to the task to see if the CPU still matches: if 'fpu_owner_task' matches the task we are switching to, we know that no other task (or kernel FPU usage) touched the FPU on this CPU in the meantime, and if the current CPU number matches the 'last_cpu' field, we know that this thread did no other FP work on any other CPU, so the FPU state on the CPU must match what was saved on last context switch. In that case, we can avoid the 'f[x]rstor' entirely, and just clear the CR0.TS bit. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-02-20i387: use 'restore_fpu_checking()' directly in task switching codeLinus Torvalds
This inlines what is usually just a couple of instructions, but more importantly it also fixes the theoretical error case (can that FPU restore really ever fail? Maybe we should remove the checking). We can't start sending signals from within the scheduler, we're much too deep in the kernel and are holding the runqueue lock etc. So don't bother even trying. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-02-20i387: fix up some fpu_counter confusionLinus Torvalds
This makes sure we clear the FPU usage counter for newly created tasks, just so that we start off in a known state (for example, don't try to preload the FPU state on the first task switch etc). It also fixes a thinko in when we increment the fpu_counter at task switch time, introduced by commit 34ddc81a230b ("i387: re-introduce FPU state preloading at context switch time"). We should increment the *new* task fpu_counter, not the old task, and only if we decide to use that state (whether lazily or preloaded). Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-02-20Merge branch 'fixes-mmc' into fixesTony Lindgren
2012-02-20ARM: OMAP: Fix build error when mmc_omap is built as module Tony Lindgren
Otherwise we get the following error: arch/arm/mach-omap2/built-in.o: In function `n8x0_mmc_callback': twl-common.c:(.text+0x108a0): undefined reference to `omap_mmc_notify_cover_event' Fix this by warning about unusable MMC cover events. The long term fix needs to change the MMC drivers to register board specific callbacks directly with PMIC. Reported-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Tony Lindgren <tony@atomide.com>
2012-02-20ARM: OMAP: Fix kernel panic with HSMMC when twl4030_gpio is a moduleTony Lindgren
On some omaps twl4030_gpio has a callback to try to initialize the MMC controller. If twl4030_gpio is compiled as a module, bad things can happen because the callback function starts calling functions that are supposed to be marked __init: Kernel panic - not syncing: Attempted to kill the idle task! twl4030_gpio twl4030_gpio: can't dispatch IRQs from modules gpiochip_add: registered GPIOs 192 to 209 on device: twl4030 Unable to handle kernel paging request at virtual address b82a4c74 ... Additionally if this does not fail, warnings are produced about trying to register the MMC multiple times. Fix this by removing __init from omap_mux_get_by_name, and add checks if omap2_hsmmc_init() is getting called more than once. Note that this will get fixed properly later on by splitting omap2_hsmmc_init into two functions. Reported-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Tony Lindgren <tony@atomide.com>
2012-02-20xen/pat: Disable PAT support for now.Konrad Rzeszutek Wilk
[Pls also look at https://lkml.org/lkml/2012/2/10/228] Using of PAT to change pages from WB to WC works quite nicely. Changing it back to WB - not so much. The crux of the matter is that the code that does this (__page_change_att_set_clr) has only limited information so when it tries to the change it gets the "raw" unfiltered information instead of the properly filtered one - and the "raw" one tell it that PSE bit is on (while infact it is not). As a result when the PTE is set to be WB from WC, we get tons of: :WARNING: at arch/x86/xen/mmu.c:475 xen_make_pte+0x67/0xa0() :Hardware name: HP xw4400 Workstation .. snip.. :Pid: 27, comm: kswapd0 Tainted: G W 3.2.2-1.fc16.x86_64 #1 :Call Trace: : [<ffffffff8106dd1f>] warn_slowpath_common+0x7f/0xc0 : [<ffffffff8106dd7a>] warn_slowpath_null+0x1a/0x20 : [<ffffffff81005a17>] xen_make_pte+0x67/0xa0 : [<ffffffff810051bd>] __raw_callee_save_xen_make_pte+0x11/0x1e : [<ffffffff81040e15>] ? __change_page_attr_set_clr+0x9d5/0xc00 : [<ffffffff8114c2e8>] ? __purge_vmap_area_lazy+0x158/0x1d0 : [<ffffffff8114cca5>] ? vm_unmap_aliases+0x175/0x190 : [<ffffffff81041168>] change_page_attr_set_clr+0x128/0x4c0 : [<ffffffff81041542>] set_pages_array_wb+0x42/0xa0 : [<ffffffff8100a9b2>] ? check_events+0x12/0x20 : [<ffffffffa0074d4c>] ttm_pages_put+0x1c/0x70 [ttm] : [<ffffffffa0074e98>] ttm_page_pool_free+0xf8/0x180 [ttm] : [<ffffffffa0074f78>] ttm_pool_mm_shrink+0x58/0x90 [ttm] : [<ffffffff8112ba04>] shrink_slab+0x154/0x310 : [<ffffffff8112f17a>] balance_pgdat+0x4fa/0x6c0 : [<ffffffff8112f4b8>] kswapd+0x178/0x3d0 : [<ffffffff815df134>] ? __schedule+0x3d4/0x8c0 : [<ffffffff81090410>] ? remove_wait_queue+0x50/0x50 : [<ffffffff8112f340>] ? balance_pgdat+0x6c0/0x6c0 : [<ffffffff8108fb6c>] kthread+0x8c/0xa0 for every page. The proper fix for this is has been posted and is https://lkml.org/lkml/2012/2/10/228 "x86/cpa: Use pte_attrs instead of pte_flags on CPA/set_p.._wb/wc operations." along with a detailed description of the problem and solution. But since that posting has gone nowhere I am proposing this band-aid solution so that at least users don't get the page corruption (the pages that are WC don't get changed to WB and end up being recycled for filesystem or other things causing mysterious crashes). The negative impact of this patch is that users of WC flag (which are InfiniBand, radeon, nouveau drivers) won't be able to set that flag - so they are going to see performance degradation. But stability is more important here. Fixes RH BZ# 742032, 787403, and 745574 Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-02-20xen/setup: Remove redundant filtering of PTE masks.Konrad Rzeszutek Wilk
commit 7347b4082e55ac4a673f06a0a0ce25c37273c9ec "xen: Allow unprivileged Xen domains to create iomap pages" added a redundant line in the early bootup code to filter out the PTE. That filtering is already done a bit earlier so this extra processing is not required. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-02-20x86/nmi: Test saved %cs in NMI to determine nested NMI caseSteven Rostedt
Currently, the NMI handler tests if it is nested by checking the special variable saved on the stack (set during NMI handling) and whether the saved stack is the NMI stack as well (to prevent the race when the variable is set to zero). But userspace may set their %rsp to any value as long as they do not derefence it, and it may make it point to the NMI stack, which will prevent NMIs from triggering while the userspace app is running. (I tested this, and it is indeed the case) Add another check to determine nested NMIs by looking at the saved %cs (code segment register) and making sure that it is the kernel code segment. Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: <stable@kernel.org> Link: http://lkml.kernel.org/r/1329687817.1561.27.camel@acer.local.home Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-02-18Merge tag 'fixes-3.3-rc4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc These are the bug fixes that have accumulated since 3.3-rc3 in arm-soc. The majority of them are regression fixes for stuff that broke during the merge 3.3 window. The notable ones are: * The at91 ata drivers both broke because of an earlier cleanup patch that some other patches were based on. Jean-Christophe decided to remove the legacy at91_ide driver and fix the new-style at91-pata driver while keeping the cleanup patch. I almost rejected the patches for being too late and too big but in the end decided to accept them because they fix a regression. * A patch fixing build breakage from the sysdev-to-device conversion colliding with other changes touches a number of mach-s3c files. * b0654037 "ARM: orion: Fix Orion5x GPIO regression from MPP cleanup" is a mechanical change that unfortunately touches a lot of lines that should up in the diffstat. * tag 'fixes-3.3-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (28 commits) ARM: at91: drop ide driver in favor of the pata one pata/at91: use newly introduced SMC accessors ARM: at91: add accessor to manage SMC ARM: at91:rtc/rtc-at91sam9: ioremap register bank ARM: at91: USB AT91 gadget registration for module ep93xx: fix build of vision_ep93xx.c ARM: OMAP2xxx: PM: fix OMAP2xxx-specific UART idle bug in v3.3 ARM: orion: Fix USB phy for orion5x. ARM: orion: Fix Orion5x GPIO regression from MPP cleanup ARM: EXYNOS: Add cpu-offset property in gic device tree node ARM: EXYNOS: Bring exynos4-dt up to date ARM: OMAP3: cm-t35: fix section mismatch warning ARM: OMAP2: Fix the OMAP2 only build break seen with 2011+ ARM tool-chains ARM: tegra: paz00: fix wrong UART port on mini-pcie plug ARM: tegra: paz00: fix wrong SD1 power gpio i2c: tegra: Add devexit_p() for remove ARM: EXYNOS: Correct M-5MOLS sensor clock frequency on Universal C210 board ARM: EXYNOS: Correct framebuffer window size on Nuri board ARM: SAMSUNG: Fix missing api-change from subsys_interface change ARM: EXYNOS: Fix "warning: initialization from incompatible pointer type" ...
2012-02-18Merge branch 'merge' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc Here are a few more fixes for powerpc. Some are regressions, the rest is simple/obvious/nasty enough that I deemed it good to go now. Here's also step one of deprecating legacy iSeries support: we are removing it from the main defconfig. Nobody seems to be using it anymore and the code is nasty to maintain, (involves horrible hacks in various low level areas of the kernel) so we plan to actually rip it out at some point. For now let's just avoid building it by default. Stephen will proceed to do the actual removal later (probably 3.4 or 3.5). * 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: powerpc/perf: power_pmu_start restores incorrect values, breaking frequency events powerpc/adb: Use set_current_state() powerpc: Disable interrupts early in Program Check powerpc: Remove legacy iSeries from ppc64_defconfig powerpc/fsl/pci: Fix PCIe fixup regression powerpc: Fix kernel log of oops/panic instruction dump
2012-02-18i387: re-introduce FPU state preloading at context switch timeLinus Torvalds
After all the FPU state cleanups and finally finding the problem that caused all our FPU save/restore problems, this re-introduces the preloading of FPU state that was removed in commit b3b0870ef3ff ("i387: do not preload FPU state at task switch time"). However, instead of simply reverting the removal, this reimplements preloading with several fixes, most notably - properly abstracted as a true FPU state switch, rather than as open-coded save and restore with various hacks. In particular, implementing it as a proper FPU state switch allows us to optimize the CR0.TS flag accesses: there is no reason to set the TS bit only to then almost immediately clear it again. CR0 accesses are quite slow and expensive, don't flip the bit back and forth for no good reason. - Make sure that the same model works for both x86-32 and x86-64, so that there are no gratuitous differences between the two due to the way they save and restore segment state differently due to architectural differences that really don't matter to the FPU state. - Avoid exposing the "preload" state to the context switch routines, and in particular allow the concept of lazy state restore: if nothing else has used the FPU in the meantime, and the process is still on the same CPU, we can avoid restoring state from memory entirely, just re-expose the state that is still in the FPU unit. That optimized lazy restore isn't actually implemented here, but the infrastructure is set up for it. Of course, older CPU's that use 'fnsave' to save the state cannot take advantage of this, since the state saving also trashes the state. In other words, there is now an actual _design_ to the FPU state saving, rather than just random historical baggage. Hopefully it's easier to follow as a result. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-02-18i387: move TS_USEDFPU flag from thread_info to task_structLinus Torvalds
This moves the bit that indicates whether a thread has ownership of the FPU from the TS_USEDFPU bit in thread_info->status to a word of its own (called 'has_fpu') in task_struct->thread.has_fpu. This fixes two independent bugs at the same time: - changing 'thread_info->status' from the scheduler causes nasty problems for the other users of that variable, since it is defined to be thread-synchronous (that's what the "TS_" part of the naming was supposed to indicate). So perfectly valid code could (and did) do ti->status |= TS_RESTORE_SIGMASK; and the compiler was free to do that as separate load, or and store instructions. Which can cause problems with preemption, since a task switch could happen in between, and change the TS_USEDFPU bit. The change to TS_USEDFPU would be overwritten by the final store. In practice, this seldom happened, though, because the 'status' field was seldom used more than once, so gcc would generally tend to generate code that used a read-modify-write instruction and thus happened to avoid this problem - RMW instructions are naturally low fat and preemption-safe. - On x86-32, the current_thread_info() pointer would, during interrupts and softirqs, point to a *copy* of the real thread_info, because x86-32 uses %esp to calculate the thread_info address, and thus the separate irq (and softirq) stacks would cause these kinds of odd thread_info copy aliases. This is normally not a problem, since interrupts aren't supposed to look at thread information anyway (what thread is running at interrupt time really isn't very well-defined), but it confused the heck out of irq_fpu_usable() and the code that tried to squirrel away the FPU state. (It also caused untold confusion for us poor kernel developers). It also turns out that using 'task_struct' is actually much more natural for most of the call sites that care about the FPU state, since they tend to work with the task struct for other reasons anyway (ie scheduling). And the FPU data that we are going to save/restore is found there too. Thanks to Arjan Van De Ven <arjan@linux.intel.com> for pointing us to the %esp issue. Cc: Arjan van de Ven <arjan@linux.intel.com> Reported-and-tested-by: Raphael Prevost <raphael@buro.asia> Acked-and-tested-by: Suresh Siddha <suresh.b.siddha@intel.com> Tested-by: Peter Anvin <hpa@zytor.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-02-17Merge branch 'for_3.3/fixes/pm' of ↵Tony Lindgren
git://git.kernel.org/pub/scm/linux/kernel/git/khilman/linux-omap-pm into fixes
2012-02-17[S390] correct ktime to tod clock comparator conversionMartin Schwidefsky
The conversion of the ktime to a value suitable for the clock comparator does not take changes to wall_to_monotonic into account. In fact the conversion just needs the boot clock (sched_clock_base_cc) and the total_sleep_time. This is applicable to 3.2+ kernels. CC: stable@vger.kernel.org Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-02-17[S390] incorrect PageTables counter for kvm page tablesMartin Schwidefsky
The page_table_free_pgste function is used for kvm processes to free page tables that have the pgste extension. It calls pgtable_page_ctor instead of pgtable_page_dtor which increases NR_PAGETABLE instead of decreasing it. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-02-17[S390] idle: avoid RCU usage in extended quiescent stateHeiko Carstens
Avoid calling wake_up() from our NMI "bottom halve" from RCU extended quiescent state in idle. wake_up() has RCU read-side critical sections but this will be completely ignored by RCU if the cpu is in extended quiescent state. Which means that whatever object is being accessed from within the read-side critical section can be freed concurrently from a different cpu. So make sure we leave extended quiescent state before calling wake_up(). Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-02-17openrisc: Fix up audit_syscall_[entry|exit]() usageJonas Bonn
Commits d7e7528bcd456f5c36ad4a202ccfb43c5aa98bc4 and b05d8447e7821695bc2fa3359431f7a664232743 simplified the usage of the audit_syscall_[entry|exit] functions. Unfortunately, the OpenRISC architecture didn't get fixed up along with the other architectures when those patches were pushed. This makes the relevant changes to this architecture. Signed-off-by: Jonas Bonn <jonas@southpole.se>
2012-02-17openrisc: include export.h for EXPORT_SYMBOLJonas Bonn
Use of EXPORT_SYMBOL requires inclusion of export.h Signed-off-by: Jonas Bonn <jonas@southpole.se>
2012-02-17pxa/hx4700: add platform device and I2C info for AK4641 codecAxel Lin
The audio on hx4700 needs this to properly work. Signed-off-by: Philipp Zabel <philipp.zabel@gmail.com> Signed-off-by: Dmitry Artamonow <mad_soft@inbox.ru> Signed-off-by: Axel Lin <axel.lin@gmail.com> Acked-by: Marek Vasut <marek.vasut@gmail.com> Tested-by: Paul Parsons <lost.distance@yahoo.com> Signed-off-by: Haojian Zhuang <haojian.zhuang@gmail.com>
2012-02-16i387: move AMD K7/K8 fpu fxsave/fxrstor workaround from save to restoreLinus Torvalds
The AMD K7/K8 CPUs don't save/restore FDP/FIP/FOP unless an exception is pending. In order to not leak FIP state from one process to another, we need to do a floating point load after the fxsave of the old process, and before the fxrstor of the new FPU state. That resets the state to the (uninteresting) kernel load, rather than some potentially sensitive user information. We used to do this directly after the FPU state save, but that is actually very inconvenient, since it (a) corrupts what is potentially perfectly good FPU state that we might want to lazy avoid restoring later and (b) on x86-64 it resulted in a very annoying ordering constraint, where "__unlazy_fpu()" in the task switch needs to be delayed until after the DS segment has been reloaded just to get the new DS value. Coupling it to the fxrstor instead of the fxsave automatically avoids both of these issues, and also ensures that we only do it when actually necessary (the FP state after a save may never actually get used). It's simply a much more natural place for the leaked state cleanup. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-02-16i387: do not preload FPU state at task switch timeLinus Torvalds
Yes, taking the trap to re-load the FPU/MMX state is expensive, but so is spending several days looking for a bug in the state save/restore code. And the preload code has some rather subtle interactions with both paravirtualization support and segment state restore, so it's not nearly as simple as it should be. Also, now that we no longer necessarily depend on a single bit (ie TS_USEDFPU) for keeping track of the state of the FPU, we migth be able to do better. If we are really switching between two processes that keep touching the FP state, save/restore is inevitable, but in the case of having one process that does most of the FPU usage, we may actually be able to do much better than the preloading. In particular, we may be able to keep track of which CPU the process ran on last, and also per CPU keep track of which process' FP state that CPU has. For modern CPU's that don't destroy the FPU contents on save time, that would allow us to do a lazy restore by just re-enabling the existing FPU state - with no restore cost at all! Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-02-16i387: don't ever touch TS_USEDFPU directly, use helper functionsLinus Torvalds
This creates three helper functions that do the TS_USEDFPU accesses, and makes everybody that used to do it by hand use those helpers instead. In addition, there's a couple of helper functions for the "change both CR0.TS and TS_USEDFPU at the same time" case, and the places that do that together have been changed to use those. That means that we have fewer random places that open-code this situation. The intent is partly to clarify the code without actually changing any semantics yet (since we clearly still have some hard to reproduce bug in this area), but also to make it much easier to use another approach entirely to caching the CR0.TS bit for software accesses. Right now we use a bit in the thread-info 'status' variable (this patch does not change that), but we might want to make it a full field of its own or even make it a per-cpu variable. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-02-16i387: move TS_USEDFPU clearing out of __save_init_fpu and into callersLinus Torvalds
Touching TS_USEDFPU without touching CR0.TS is confusing, so don't do it. By moving it into the callers, we always do the TS_USEDFPU next to the CR0.TS accesses in the source code, and it's much easier to see how the two go hand in hand. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-02-16i387: fix x86-64 preemption-unsafe user stack save/restoreLinus Torvalds
Commit 5b1cbac37798 ("i387: make irq_fpu_usable() tests more robust") added a sanity check to the #NM handler to verify that we never cause the "Device Not Available" exception in kernel mode. However, that check actually pinpointed a (fundamental) race where we do cause that exception as part of the signal stack FPU state save/restore code. Because we use the floating point instructions themselves to save and restore state directly from user mode, we cannot do that atomically with testing the TS_USEDFPU bit: the user mode access itself may cause a page fault, which causes a task switch, which saves and restores the FP/MMX state from the kernel buffers. This kind of "recursive" FP state save is fine per se, but it means that when the signal stack save/restore gets restarted, it will now take the '#NM' exception we originally tried to avoid. With preemption this can happen even without the page fault - but because of the user access, we cannot just disable preemption around the save/restore instruction. There are various ways to solve this, including using the "enable/disable_page_fault()" helpers to not allow page faults at all during the sequence, and fall back to copying things by hand without the use of the native FP state save/restore instructions. However, the simplest thing to do is to just allow the #NM from kernel space, but fix the race in setting and clearing CR0.TS that this all exposed: the TS bit changes and the TS_USEDFPU bit absolutely have to be atomic wrt scheduling, so while the actual state save/restore can be interrupted and restarted, the act of actually clearing/setting CR0.TS and the TS_USEDFPU bit together must not. Instead of just adding random "preempt_disable/enable()" calls to what is already excessively ugly code, this introduces some helper functions that mostly mirror the "kernel_fpu_begin/end()" functionality, just for the user state instead. Those helper functions should probably eventually replace the other ad-hoc CR0.TS and TS_USEDFPU tests too, but I'll need to think about it some more: the task switching functionality in particular needs to expose the difference between the 'prev' and 'next' threads, while the new helper functions intentionally were written to only work with 'current'. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-02-16arch/arm/mach-pxa/: included linux/gpio.h twiceDanny Kukawka
arch/arm/mach-pxa/pxa25x.c and arch/arm/mach-pxa/saarb.c included 'linux/gpio.h' twice, remove the duplicates. Signed-off-by: Danny Kukawka <danny.kukawka@bisect.de> Signed-off-by: Haojian Zhuang <haojian.zhuang@gmail.com>
2012-02-16arch/arm/mach-mmp/: some files include some headers twiceDanny Kukawka
arch/arm/mach-mmp/: some files include some headers twice: - arch/arm/mach-mmp/aspenite.c and arch/arm/mach-mmp/tavorevb.c: 'linux/gpio.h' - arch/arm/mach-mmp/pxa168.c: 'linux/platform_device.h' Remove the duplicates. Signed-off-by: Danny Kukawka <danny.kukawka@bisect.de> Signed-off-by: Haojian Zhuang <haojian.zhuang@gmail.com>
2012-02-16powerpc/perf: power_pmu_start restores incorrect values, breaking frequency ↵Anton Blanchard
events perf on POWER stopped working after commit e050e3f0a71b (perf: Fix broken interrupt rate throttling). That patch exposed a bug in the POWER perf_events code. Since the PMCs count upwards and take an exception when the top bit is set, we want to write 0x80000000 - left in power_pmu_start. We were instead programming in left which effectively disables the counter until we eventually hit 0x80000000. This could take seconds or longer. With the patch applied I get the expected number of samples: SAMPLE events: 9948 Signed-off-by: Anton Blanchard <anton@samba.org> Acked-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: <stable@kernel.org>
2012-02-16powerpc: Disable interrupts early in Program CheckBenjamin Herrenschmidt
Program Check exceptions are the result of WARNs, BUGs, some type of breakpoints, kprobe, and other illegal instructions. We want interrupts (and thus preemption) to remain disabled while doing the initial stage of testing the reason and branching off to a debugger or kprobe, so we are still on the original CPU which makes debugging easier in various cases. This is how the code was intended, hence the local_irq_enable() right in the middle of program_check_exception(). However, the assembly exception prologue for that exception was incorrectly marked as enabling interrupts, which defeats that (and records a redundant enable with lockdep). Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-02-16powerpc: Remove legacy iSeries from ppc64_defconfigStephen Rothwell
Since we are heading towards removing the Legacy iSeries platform, start by no longer building it for ppc64_defconfig. Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-02-16powerpc/fsl/pci: Fix PCIe fixup regressionBenjamin Herrenschmidt
Upstream changes to the way PHB resources are registered broke the resource fixup for FSL boards. We can no longer rely on the resource pointer array for the PHB's pci_bus structure, so let's leave it alone and go straight for the PHB resources instead. This also makes the code generally more readable. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-02-16powerpc: Fix kernel log of oops/panic instruction dumpIra Snyder
A kernel oops/panic prints an instruction dump showing several instructions before and after the instruction which caused the oops/panic. The code intended that the faulting instruction be enclosed in angle brackets, however a bug caused the faulting instruction to be interpreted by printk() as the message log level. To fix this, the KERN_CONT log level is added before the actual text of the printed message. === Before the patch === [ 1081.587266] Instruction dump: [ 1081.590236] 7c000110 7c0000f8 5400077c 552907f6 7d290378 992b0003 4e800020 38000001 [ 1081.598034] 3d20c03a 9009a114 7c0004ac 39200000 [ 1081.602500] 4e800020 3803ffd0 2b800009 <4>[ 1081.587266] Instruction dump: <4>[ 1081.590236] 7c000110 7c0000f8 5400077c 552907f6 7d290378 992b0003 4e800020 38000001 <4>[ 1081.598034] 3d20c03a 9009a114 7c0004ac 39200000 <98090000>[ 1081.602500] 4e800020 3803ffd0 2b800009 === After the patch === [ 51.385216] Instruction dump: [ 51.388186] 7c000110 7c0000f8 5400077c 552907f6 7d290378 992b0003 4e800020 38000001 [ 51.395986] 3d20c03a 9009a114 7c0004ac 39200000 <98090000> 4e800020 3803ffd0 2b800009 <4>[ 51.385216] Instruction dump: <4>[ 51.388186] 7c000110 7c0000f8 5400077c 552907f6 7d290378 992b0003 4e800020 38000001 <4>[ 51.395986] 3d20c03a 9009a114 7c0004ac 39200000 <98090000> 4e800020 3803ffd0 2b800009 Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: linuxppc-dev@lists.ozlabs.org Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-02-16ARM: pxa: fix including linux/gpio.h twiceDanny Kukawka
arch/arm/mach-pxa/pxa27x.c included 'linux/gpio.h' twice, remove the duplicate. Signed-off-by: Danny Kukawka <danny.kukawka@bisect.de> Signed-off-by: Haojian Zhuang <haojian.zhuang@gmail.com>
2012-02-16ARM: pxa: fix mixed declarations and code in sharpsl_pmHaojian Zhuang
arch/arm/mach-pxa/sharpsl_pm.c: In function 'sharpsl_pm_pxa_read_max1111': arch/arm/mach-pxa/sharpsl_pm.c:180: warning: ISO C90 forbids mixed declarations and code Signed-off-by: Haojian Zhuang <haojian.zhuang@marvell.com>
2012-02-16ARM: pxa: fix wrong parsing gpio event on spitzHaojian Zhuang
(~GPLR0 & GPIO_bit(SPITZ_GPIO_KEY_INT)) | (GPLR0 & GPIO_bit(SPITZ_GPIO_SYNC)); After using gpio_get_value, the statement should be in below. ((!gpio_get_value(SPITZ_GPIO_KEY_INT) << GPIO_bit(SPITZ_GPIO_KEY_INT)) | gpio_get_value(SPITZ_GPIO_SYNC)); Signed-off-by: Haojian Zhuang <haojian.zhuang@marvell.com>
2012-02-15ARM: 7327/1: need to include asm/system.h in asm/processor.hOlof Johansson
For files that include asm/processor.h but not asm/system.h: arch/arm/mach-msm/include/mach/uncompress.h: In function 'putc': arch/arm/mach-msm/include/mach/uncompress.h:48:3: error: implicit declaration of function 'smp_mb' [-Werror=implicit-function-declaration] In this case, smp_mb() is from the cpu_relax() call in the msm putc(). It likely went uncaught when the uncompress.h change went in since the defconfig didn't enable that code path, but later changes (e76f4750f4: ARM: debug: arrange Kconfig options more logically) resulted in the option being on for msm_defconfig and thus exposed it. Signed-off-by: Olof Johansson <olof@lixom.net> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-02-15ARM: 7326/2: PL330: fix null pointer dereference in pl330_chan_ctrl()Javi Merino
This fixes the thrd->req_running field being accessed before thrd is checked for null. The error was introduced in abb959f: ARM: 7237/1: PL330: Fix driver freeze Reference: <1326458191-23492-1-git-send-email-mans.rullgard@linaro.org> Cc: stable@kernel.org Signed-off-by: Mans Rullgard <mans.rullgard@linaro.org> Acked-by: Javi Merino <javi.merino@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-02-15ARM: 7164/3: PL330: Fix the size of the dst_cache_ctrl fieldJavi Merino
dst_cache_ctrl affects bits 3, 1 and 0 of AWCACHE but it is a 3-bit field in the Channel Control Register (see Table 3-21 of the DMA-330 Technical Reference Manual) and should be programmed as such. Reference: <1320244259-10496-3-git-send-email-javi.merino@arm.com> Signed-off-by: Javi Merino <javi.merino@arm.com> Acked-by: Jassi Brar <jassisinghbrar@gmail.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-02-15ARM: 7325/1: fix v7 boot with lockdep enabledRabin Vincent
Bootup with lockdep enabled has been broken on v7 since b46c0f74657d ("ARM: 7321/1: cache-v7: Disable preemption when reading CCSIDR"). This is because v7_setup (which is called very early during boot) calls v7_flush_dcache_all, and the save_and_disable_irqs added by that patch ends up attempting to call into lockdep C code (trace_hardirqs_off()) when we are in no position to execute it (no stack, MMU off). Fix this by using a notrace variant of save_and_disable_irqs. The code already uses the notrace variant of restore_irqs. Reviewed-by: Nicolas Pitre <nico@linaro.org> Acked-by: Stephen Boyd <sboyd@codeaurora.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: stable@vger.kernel.org Signed-off-by: Rabin Vincent <rabin@rab.in> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-02-15i387: fix sense of sanity checkLinus Torvalds
The check for save_init_fpu() (introduced in commit 5b1cbac37798: "i387: make irq_fpu_usable() tests more robust") was the wrong way around, but I hadn't noticed, because my "tests" were bogus: the FPU exceptions are disabled by default, so even doing a divide by zero never actually triggers this code at all unless you do extra work to enable them. So if anybody did enable them, they'd get one spurious warning. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-02-15ARM: 7323/1: Do not allow ARM_LPAE on pre-ARMv7 architecturesCatalin Marinas
This patch expands the Kconfig dependencies for ARM_LPAE to not allow enabling when architectures other than ARMv7 are built into the kernel. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Reported-by: Russell King <linux@arm.linux.org.uk> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-02-14Kbuild: Use dtc's -d (dependency) optionStephen Warren
This hooks dtc into Kbuild's dependency system. Thus, for example, "make dtbs" will rebuild tegra-harmony.dtb if only tegra20.dtsi has changed yet tegra-harmony.dts has not. The previous lack of this feature recently caused me to have very confusing "git bisect" results. For ARM, it's obvious what to add to $(targets). I'm not familiar enough with other architectures to know what to add there. Powerpc appears to already add various .dtb files into $(targets), but the other archs may need something added to $(targets) to work. Signed-off-by: Stephen Warren <swarren@nvidia.com> Acked-by: Shawn Guo <shawn.guo@linaro.org> Acked-by: Mark Salter <msalter@redhat.com>
2012-02-14Merge branch 'merge' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc Quoth BenH: "Here are a few powerpc fixes for 3.3, all pretty trivial. I also added the patch to define GET_IP/SET_IP so we can use some more asm-generic goodness." * 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: powerpc/pseries/eeh: Fix crash when error happens during device probe powerpc/pseries: Fix partition migration hang in stop_topology_update powerpc/powernv: Disable interrupts while taking phb->lock powerpc: Fix WARN_ON in decrementer_check_overflow powerpc/wsp: Fix IRQ affinity setting powerpc: Implement GET_IP/SET_IP powerpc/wsp: Permanently enable PCI class code workaround
2012-02-14Merge tag 'stable/for-linus-fixes-3.3-rc3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen Two fixes for VCPU offlining; One to fix the string format exposed by the xen-pci[front|back] to conform to the one used in majority of PCI drivers; Two fixes to make the code more resilient to invalid configurations. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> * tag 'stable/for-linus-fixes-3.3-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: xenbus_dev: add missing error check to watch handling xen/pci[front|back]: Use %d instead of %1x for displaying PCI devfn. xen pvhvm: do not remap pirqs onto evtchns if !xen_have_vector_callback xen/smp: Fix CPU online/offline bug triggering a BUG: scheduling while atomic. xen/bootup: During bootup suppress XENBUS: Unable to read cpu state
2012-02-14ARM: OMAP2+: usb-host: fix compile warningFelipe Balbi
when commit 3528c58 (OMAP: omap_device: when building return platform_device instead of omap_device) started returning a platform_device instead of a omap_device pointer when building a device, it failed to convert all users introducing a compile warning when building arch/arm/mach-omap2/usb-host.c. This patch fixes that warning. Signed-off-by: Felipe Balbi <balbi@ti.com> Signed-off-by: Tony Lindgren <tony@atomide.com>
2012-02-14ARM: OMAP4: Move the barrier memboclk_steal() as part of reserve callbackSantosh Shilimkar
arm_memblock_steal() is not suppose to be used outside ->reserve callback. OMAP barrier errata code was using it outside reserve callback and hence it was broken. Move the allocation as part of ->reserve callback to fix the it. Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Signed-off-by: Tony Lindgren <tony@atomide.com>
2012-02-14ARM: OMAP4: cpuidle: Fix the C-state reporting to cpuidle governor.Santosh Shilimkar
OMAP4 cpuidle driver is reporting the state requested by governor rather than the actually attempted one. This is obviously misleading sysfs and powertop cpuidle statistics. Fix it so that stats are reported correctly. Reported-by: Kevin Hilman <khilman@ti.com> Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com> [khilman@ti.com: minor changelog edits] Signed-off-by: Kevin Hilman <khilman@ti.com>